Keelung, Taiwan

National Taiwan Ocean University is a national university in Zhongzheng District, Keelung, Taiwan. Wikipedia.

Time filter

Source Type

Lee W.-K.,National Taiwan Ocean University | Tsai M.-L.,National Taiwan Ocean University | Shieh Y.-T.,National University of Kaohsiung
Journal of Supercritical Fluids | Year: 2012

Chitosan was extracted by supercritical carbon dioxide (scCO 2) containing 1 wt% acetic acid (AC) aqueous solution as a cosolvent at 35, 45, 50 °C and 20, 30, 40 MPa for 1 h. Effects of operating conditions on the extraction yield and on the degree of deacetylation (DD), molecular weight (MW), and polydispersity (PD) of the extract were investigated. Without the AC cosolvent, chitosan could scarcely be extracted by pure scCO 2 whereas, with the AC in scCO 2, 1.65-3.04% by weight of chitosan could be extracted with the conditions studied. The extraction yield was increased by increasing density of scCO 2. The extract had lower MW and PD but higher DD than the untreated chitosan. The DD data revealed that in chitosan the amount of the amino groups (NH 2) other than the carbonyl (CO) in the residual acetyl groups (CH 3CO) governed the extraction process. The DD, MW, and PD of the extract were higher as extracted by scCO 2 (+1 wt% AC solution) of higher densities. By tuning density of scCO 2 in the presence of AC via controls of temperature and pressure, chitosan could be fractionated by the method established here. © 2012 Elsevier B.V. All rights reserved.

Chiang T.-Y.,National Cheng Kung University | Chen I.-S.,National Taiwan Ocean University | Chang W.-B.,National Museum of Marine Biology and Aquarium | Ju Y.-M.,National Cheng Kung University
Mitochondrial DNA | Year: 2013

In this study, we sequenced the complete mitochondrial genome of Sicyopterus japonicus (Perciformes, Gobiidae). This mitochondrial genome consists of 16,514 base pairs (bp), with 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and 1 non-coding control region (CR), also with the gene synteny identical to that of typical vertebrates. CR, of 843 bp in length, is located between tRNAPro and tRNAPhe. The overall base composition of the heavy strand shows T 26.1%, C 28.7%, A 28.3%, and G 16.91%, with a slight AT bias of 54.4%. © 2013 Informa UK, Ltd.

Tsang L.M.,National Taiwan Ocean University | Tsang L.M.,Chinese University of Hong Kong | Schubart C.D.,University of Regensburg | Ahyong S.T.,South Australian Museum | And 6 more authors.
Molecular Biology and Evolution | Year: 2014

Crabs of the infra-order Brachyura are one of the most diverse groups of crustaceans with approximately 7,000 described species in 98 families, occurring in marine, freshwater, and terrestrial habitats. The relationships among the brachyuran families are poorly understood due to the high morphological complexity of the group. Here, we reconstruct the most comprehensive phylogeny of Brachyura to date using sequence data of six nuclear protein-coding genes and two mitochondrial rRNA genes from more than 140 species belonging to 58 families. The gene tree confirms that the "Podotremata," are paraphyletic. Within the monophyletic Eubrachyura, the reciprocal monophyly of the two subsections, Heterotremata and Thoracotremata, is supported. Monophyly of many superfamilies, however, is not recovered, indicating the prevalence of morphological convergence and the need for further taxonomic studies. Freshwater crabs were derived early in the evolution of Eubrachyura and are shown to have at least two independent origins. Bayesian relaxed molecular methods estimate that freshwater crabs separated from their closest marine sister taxa ~135Ma, that is, after the break up of Pangaea (~200 Ma) and that a Gondwanan origin of these freshwater representatives is untenable. Most extant families and superfamilies arose during the late Cretaceous and early Tertiary. © The Author 2014.

Ko H.-L.,Academia Sinica, Taiwan | Wang Y.-T.,Taiwanese Fisheries Research Institute | Chiu T.-S.,National Taiwan University | Lee M.-A.,National Taiwan Ocean University | And 4 more authors.
PLoS ONE | Year: 2013

Due to insufficient morphological diagnostic characters in larval fishes, it is easy to misidentify them and difficult to key to the genus or species level. The identification results from different laboratories are often inconsistent. This experiment aims to find out, by applying DNA barcoding, how inconsistent the identifications can be among larval fish taxonomists. One hundred morphotypes of larval fishes were chosen as test specimens. The fishes were collected with either larval fish nets or light traps in the northern, southern and northwestern waters of Taiwan. After their body lengths (SL) were measured and specimen photos were taken, all specimens were delivered, in turn, to five laboratories (A-E) in Taiwan to be identified independently. When all the results were collected, these specimens were then identified using COI barcoding. Out of a total of 100 specimens, 87 were identified to the family level, 79 to the genus level and 69 to the species level, based on the COI database currently available. The average accuracy rates of the five laboratories were quite low: 80.1% for the family level, 41.1% for the genus level, and 13.5% for the species level. If the results marked as "unidentified" were excluded from calculations, the rates went up to 75.4% and 43.7% for the genus and species levels, respectively. Thus, we suggest that larval fish identification should be more conservative; i.e., when in doubt, it is better to key only to the family and not to the genus or species level. As to the most misidentified families in our experiment, they were Sparidae, Scorpaenidae, Scombridae, Serranidae and Malacanthidae. On the other hand, Mene maculata and Microcanthus strigatus were all correctly identified to the species level because their larvae have distinct morphology. Nevertheless, barcoding remains one of the best methods to confirm species identification. © 2013 Ko et al.

Tan S.-W.,National Taiwan Ocean University | Tsai J.-H.,National Kaohsiung Normal University | Lai S.-W.,National Taiwan Ocean University | Lo C.,National Sun Yat - sen University | Lour W.-S.,National Taiwan Ocean University
International Journal of Hydrogen Energy | Year: 2011

Pd-based mixtures comprising silicon dioxide (SiO2) were used as sensing materials in fabrication of GaN-based hydrogen sensors. The mixture as-deposited has a rough surface with many pores. After wet selectively etching to remove SiO2, the mixture turns into Pd nanoparticles with a size of ∼ 30 nm on an interlayer with oxygen, as indicated by SEM, EDX, and SIMS methods. A careful study of the Pd-mixture on a metal-semiconductor-metal type of hydrogen sensor provides significant information on the roles of oxygen and the interlayer. Experimental results reveal that hydrogen atoms trapped inside the mixture as-deposited cannot contribute to changes in barrier height as an applied voltage is not large enough. Improved sensing properties such as hydrogen dissociation rate, diffusion rate, and storage capability were obtained when Pd nanoparticles were formed by selectively etching the mixture. The situation that hydrogen atoms were blocked and disturbed by oxygen will exist no more. Uniform sensing responses of higher than 105 (defined as (JH2-JN2)/JN2, JH2 and J N2 are current densities measured in H2/N2 and N2 ambiences, respectively), voltage shifts of larger than 20 V were obtained at 2.13 ppm H2/N2. In addition, hydrogen transport through grain boundaries of Pd nanoparticles is much faster than diffusion through a Pd-mixture layer. A much shorter response time was obtained from the sensors with the Pd-mixture wet etched. Furthermore, stable and reliable sensing characteristics were also expected. © 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

Pemg B.-Y.,Taipei Medical University Hospital | Wu C.-W.,National Taiwan Ocean University | Shen Y.-K.,Taipei Medical University | Lin Y.,Takming University of Science and Technology
Polymers for Advanced Technologies | Year: 2010

The application of silicon mold inserts by micro-hot embossing molding has been explored in microfluidic chip fabrication. For the mold insert, this study employed an SU-8 photoresist to coat the silicon wafer. Ultraviolet light was then used to expose the pattern on the SU-8 photoresist surface. This study replicates the microstructure of the silicon mold insert by micro-hot embossing molding. Different processing parameters (embossing temperature, embossing pressure, embossing time, and de-molding temperature) for the cycle-olefin polymer (COP) film of microfluidic chips are evaluated. The results showed that the most important parameter for replication of molded microfluidic chip is embossing temperature. De-molding temperature is the most important parameter for surface roughness of the molded microfluidic chip. The microchannel is bonded with a cover by thermal bonding processing to form the sealed microfluidic chip. The bonding temperature is the most important factor in the bonding strength of the sealed microfluidic chip. © 2009 John Wiley & Sons, Ltd.

Wang J.-P.,National Taiwan Ocean University
International Journal of Advanced Manufacturing Technology | Year: 2015

This paper proposes a novel approach to fine blanking. The V-ring indenter used in conventional fine blanking is no longer required; a trough on the die is used instead. In this approach, the cutting process combined with high hydrostatic stresses produced from the trough on the die cutting edge can substantially decrease the fracture in the shear zone. A series of experimental tests with experimental specimens of various thicknesses was conducted. The burnished surface obtained from this approach can nearly achieve the complete thickness of the blank in one operation, suggesting that the fracture zone can be nearly eliminated. In addition, the surface roughness of the burnished surface range was measured between 0.03 and 0.08 μm, and the tolerance band for the diameter was between IT2 and IT4. These results indicate an improvement in the values obtained using conventional fine blanking. © 2014, Springer-Verlag London.

Liu K.-K.,National Central University | Chao S.-Y.,University of Cambridge | Lee H.-J.,National Taiwan Ocean University | Gong G.-C.,National Taiwan Ocean University | Teng Y.-C.,National Central University
Deep-Sea Research Part II: Topical Studies in Oceanography | Year: 2010

The seasonal variation of phytoplankton growth in the East China Sea (ECS) is simulated with a three-dimensional coupled physical-biogeochemical model, which includes discharges from Changjiang (Yangtze River). The purpose is to determine the main control on the seasonality of primary productivity in the ECS shelf, which nurtures rich biological resources. The model has a horizontal resolution of 1/6° in the domain from 23°N to 41°N and from 116°E to 134°E, excluding the Japan/East Sea, and 33 layers in the vertical. The nitrogen-based biogeochemical model has four compartments: dissolved inorganic nitrogen (DIN), phytoplankton, zooplankton and detritus. The chlorophyll to phytoplankton ratio depends on light and DIN availability. The model is driven by monthly climatological winds with the sea-surface temperature, salinity and DIN relaxed towards the climatological mean values. It successfully reproduces the observed seasonal variation of primary productivity over the ECS shelf with a strong peak in later spring and summer. The modeled annual mean primary production (PP) over the entire ECS shelf is 441mgCm-2d-1, which falls within the reported range of 390-529mgCm-2d-1. It also reproduces the marked seaward gradient of DIN that decreases away from the Changjiang plume. Strong dependency on the amount of photosynthetically active radiation (PAR) is demonstrated for primary production. For 1% change in PAR 0.7% change in PP is effected. Numerical experiments show that the strong summer peak of DIN load from Changjiang cannot generate the seasonality of PP without the seasonal cycle of PAR. On the other hand, the model can still produces the seasonal pattern with Changjiang nutrient load set to zero, indicating light availability as the major control. Yet the Changjiang DIN load induces a PP increase of 77mgCm-2d-1, which represents 13-20% of the observation based estimates of PP. It is noted that the increase in nitrogen uptake associated with PP is 2.7 times the DIN provided by the Changjiang discharge, implying efficient recycling of the riverine nutrients in the shelf water. The model needs improvement on the sluggish dispersion of the Changjiang plume and insufficient vertical mixing. It also needs a more complicated biogeochemical model with more size classes of organisms, multiple-nutrient schemes and additional geochemical processes. © 2010 Elsevier Ltd.

Huang Y.J.,National Chiao Tung University | Tzeng Y.S.,National Chiao Tung University | Tang C.Y.,National Chiao Tung University | Chiang S.Y.,National Chiao Tung University | And 2 more authors.
Optics Letters | Year: 2014

We originally present a novel tactic to accomplish a compact efficient dual-wavelength synchronously mode-locked laser by physically combining the Nd:YVO4 crystal to the Nd:GdVO4 crystal as a composite gain medium. With the developed method, the total output power at 1.06 μm could be effectually produced to reach 1.3 W under the optimally balanced two-color intensities. The corresponding mode-locked pulse width and repetition rate are measured to be 47 ps and 2.86 GHz, respectively. Through the optical beating between two carrier frequencies of dual-color synchronous pulses, a train of 0.32 THz ultrashort pulses is further generated with the effective duration of down to 1.6 ps. © 2014 Optical Society of America.

Chung L.-Y.,National Yang Ming University | Tang S.-J.,National Taiwan Ocean University | Sun G.-H.,Tri Service General Hospital and National Defense Medical Center | Chou T.-Y.,Taipei Veterans General Hospital | And 3 more authors.
Clinical Cancer Research | Year: 2012

Purpose: This study is aimed at investigating the role and novel molecular mechanisms of galectin-1 in lung cancer progression. Experimental Design: The role of galectin-1 in lung cancer progression was evaluated both in vitro and in vivo by short hairpinRNA(shRNA)-mediated knockdown of galectin-1 in lung adenocarcinoma cell lines. To explore novel molecular mechanisms underlying galectin-1-mediated tumor progression, we analyzed gene expression profiles and signaling pathways using reverse transcription PCR and Western blotting. A tissue microarray containing samples from patients with lung cancer was used to examine the expression of galectin-1 in lung cancer. Results: We found overexpression of galectin-1 in non-small cell lung cancer (NSCLC) cell lines. Suppression of endogenous galectin-1 in lung adenocarcinoma resulted in reduction of the cell migration, invasion, and anchorage-independent growth in vitro and tumor growth in mice. In particular, COX-2 was downregulated in galectin-1-knockdown cells. The decreased tumor invasion and anchorage-independent growth abilities were rescued after reexpression of COX-2 in galectin-1-knockdown cells. Furthermore, we found that TGF-β1 promoted COX-2 expression through galectin-1 interaction with Ras and subsequent activation of p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase (ERK), and NF-κB pathway. Galectin-1 knockdown sensitized lung cancer cells to platinum-based chemotherapy (cisplatin). In addition, galectin-1 and COX-2 expression was correlated with the progression of lung adenocarcinoma, and high clinical relevance of both proteins was evidenced (n = 47). Conclusions: p38 MAPK, ERK, and COX-2 activation are novel mediators for the galectin-1-promoted tumor progression and chemoresistance in lung cancer. Galectin-1 may be an innovative target for combined modality therapy for lung cancer. ©2012 American Association for Cancer Research.

Lo C.,National Sun Yat - sen University | Tan S.-W.,National Taiwan Ocean University | Wei C.-Y.,National Taiwan Ocean University | Tsai J.-H.,National Kaohsiung Normal University | Lour W.-S.,National Taiwan Ocean University
International Journal of Hydrogen Energy | Year: 2013

Zigzag-shaped pure-Pd thin film and Pd-SiO2 thin-film mixture as resistive-type hydrogen sensors were deposited on cover-glass substrates through a multiple-boat thermal evaporator. Temperature dependence of the resistance of the pure-Pd resistive-type sensor showed a relative sensitivity of 3.2% at 80°C with a temperature coefficient of the resistance (TCR) of 0.058%/°C. Sensing properties of the Pd-SiO2 resistive-type sensor responding to the presence of 1% H2/N2 are much better than those of the pure-Pd one, including a higher relative sensitivity (9%-7.7%), a faster response time (10 s-30 s), and a lower detection concentration limit (50 ppm-100 ppm). A higher dissociation rate and a faster diffusion rate due to porous-like properties and more hydrogen atoms caught due to oxygen associated with the Pd-SiO2 thin-film mixture explain why the Pd-SiO2 resistive-type sensor has a higher relative sensitivity with a shorter response time. © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

Syu Y.,National Taipei University of Technology | Ma S.-P.,National Taiwan Ocean University | Kuo J.-Y.,National Taipei University of Technology | FanJiang Y.-Y.,Fu Jen Catholic University
Proceedings - 2012 IEEE 9th International Conference on Services Computing, SCC 2012 | Year: 2012

As a promising, low-cost, and agile way to develop software, in recent years automatic service composition has been a popular research topic receiving a lot of attentions. For this topic, upon our long-term study and paper reviewed, we present technical survey and observation in this paper, includingindispensablebackgroundandpreliminary knowledge. The survey assumes under traditional composition context. Moreover, following the survey and observation, we suggest two approach patterns and point out possible future challenge as well as direction, especially to the influence of the mature of mobile devices and environment. © 2012 IEEE.

Yao W.-H.,National Central University | Tung P.-C.,National Central University | Fuh C.-C.,National Taiwan Ocean University | Chou F.-C.,National Central University
IEEE Transactions on Industrial Electronics | Year: 2011

A robust uncertainty controller with a system delay compensation for an ironless linear permanent-magnet synchronous motor (ILPMSM) system with unknown system parameters has been investigated. The proposed controller consists of an inverse of the first-order reference model with an input deduction and integral term. The system delay compensation adopts an inverse system delay model to compensate the system transport delay effect. The proposed control scheme can reduce modeling uncertainty due to the difference between the reference model and the unknown real system model and disturbance due to d-q-axis coupling effect. The advantages of the proposed control algorithm are as follows: First, the system response which can be achieved is similar to that of the designed nominal reference model. In other words, the dc gain of the controlled system is denoted as one, so the proposed algorithm does not need to be combined with other control algorithms. Second, it does not require the system parameters to be known precisely. Our experimental results confirm the feasibility of the proposed scheme to compensate for the effects of uncertainty disturbances and system transport delay in the practical application of an ILPMSM system with unknown parameters. © 2011 IEEE.

Lin F.,National Taipei University of Technology | Liang D.,National Central University | Chen E.,National Taiwan Ocean University
Expert Systems with Applications | Year: 2011

Recent research has used financial ratios to establish the diagnosis models for business crises. This research explores a broader coverage of financial features, namely the recommended financial ratios from TEJ (Taiwan Economic Journal) database in addition to those financial ratios studied in prior literature. The aim of this research is to discover potentially useful but previously unaware financial features for better prediction accuracy. In this study, we had applied data mining techniques to identify five useful financial ratios, which two of them, tax rates and continuous four quarterly EPS are previously unaware to the research community. Our empirical experiment indicates that our proposed feature set outperforms those models proposed by prior scholars in terms of the prediction accuracy. © 2011 Elsevier Ltd. All rights reserved.

Lin C.-C.,National Taiwan Ocean University | Chang C.-C.,National Taiwan Ocean University | Liang D.,National Central University
Proceedings - 2012 International Symposium on Biometrics and Security Technologies, ISBAST 2012 | Year: 2012

Mouse-dynamics-related schemes have been shown to be feasible for user authentication systems, however, the existing approaches are either intrusive or not prompt response. Preventing unauthorized accesses to critical digital assets, namely, data stored in the file management system, is one of the major objectives of user authentication. We therefore propose a non-intrusive approach capable of verifying a user having performed a few times of file-related operations via a mouse. To evaluate the effectiveness of the proposed approach, the mouse movement of the file-related operations in Explorer, which is the most common way to search, open, save, copy, and/or delete files in Windows environments, is used for authentication. The experimental results show that the proposed approach is feasible and has three advantages: 1) it is non-intrusive, 2) it authenticates users in a short period of time, and 3) the quantity of mouse dynamics used for authentication purpose is lightweight. © 2012 IEEE.

Liu C.-S.,National Taiwan University | Kuo C.-L.,National Taiwan Ocean University | Liu D.,Shanghai University
Computers, Materials and Continua | Year: 2011

The inverse Cauchy problems for elliptic equations, such as the Laplace equation, the Poisson equation, the Helmholtz equation and the modified Helmholtz equation, defined in annular domains are investigated. The outer boundary of the annulus is imposed by overspecified boundary data, and we seek unknown data on the inner boundary through the numerical solution by a spring-damping regularization method and its Lie-group shooting method (LGSM). Several numerical examples are examined to show that the LGSM can overcome the ill-posed behavior of inverse Cauchy problem against the disturbance from random noise, and the computational cost is very cheap. Copyright © 2011 Tech Science Press.

Hsieh C.-W.,National Central University | Hsu H.-H.,Tamkang University | Pai T.-W.,National Taiwan Ocean University
International Journal of Data Mining and Bioinformatics | Year: 2013

To determine the structure of a protein by X-ray crystallography, the protein needs to be purified and crystallized first. However, some proteins cannot be crystallized. This makes the average cost of protein structure determination much higher. Thus it is desired to predict the crystallizability of a protein by a computational method before starting the wet-lab procedure. Features from the primary structure of a target protein are collected first. With a proper set of features, protein crystallizability can be predicted with a high accuracy. In this research, 74 features from previous researches are re-examined by two filter-mode feature selection methods. The selected features are then used for crystallization prediction by three versions of AdaBoost. The Support Vector Machines (SVMs) are also tested for comparison. The best prediction accuracy of AdaBoost reaches 93 percent and 48 important features are identified from the collected 74 features. Copyright © 2013 Inderscience Enterprises Ltd.

Wu T.-S.,National Taiwan Ocean University | Lin H.-Y.,National Chiao Tung University | Hu W.-C.,Fo Guang University | Chen Y.-S.,National Taiwan Ocean University
Expert Systems with Applications | Year: 2011

Watermark is some imperceptible information embedded into the work for later verification and thus it can be used to prove the originality or to protect the work from being illegally copied or modified. Kaabneh and Youssef (2001) proposed a muteness-based watermarking method for audio file. Their method can successfully embed watermarking information into audio file such that the human ears cannot distinguish the covered work from the original one. To improve the efficiency, we proposed a watermarking method for audio files in this paper. By adjusting the length of mute period dynamically, the proposed method can achieve the goal of watermark embedding with little variation of the original work. Experiment has shown that our method has the advantages of efficiency and fidelity as compared with theirs. Furthermore, it does not require the original audio file to derive the embedded watermark. © 2010 Elsevier Ltd. All rights reserved.

Yang T.-T.,National Chiao Tung University | Chen W.-T.,National Chiao Tung University | Hsu Y.-J.,National Chiao Tung University | Wei K.-H.,National Chiao Tung University | And 2 more authors.
Journal of Physical Chemistry C | Year: 2010

The interfacial charge carrier dynamics for core-shell Au-CdS nanocrystals with various shell thicknesses were investigated and presented. Due to the difference in band structures between Au and CdS, a pronounced photoinduced charge separation took place at the interface of Au and CdS, resulting in the electron-charged Au core and the hole-enriched CdS shell. The electron-charging of Au core in Au-CdS nanocrystals was revealed with the corresponding XPS analysis and photocurrent measurement. Time-resolved PL spectra were measured to quantitatively analyze the electron transfer event between CdS shell and Au core for Au-CdS nanocrystals. An increase in the electron-transfer rate constant was observed for Au-CdS nanocrystals with increasing shell thickness, probably due to the less pronounced electron-hole interaction of thicker CdS, which enabled a fuller extent of participation of photoexcited electrons in the charge separation process. On the other hand, the hole-enriched CdS shell of Au-CdS nanocrystals upon light illumination was characterized with a photocatalytic process. The photocatalytic activity of Au-CdS nanocrystals was found to increase with increasing shell thickness, attributable to the greater capability of light absorption achieved by the extensive growth of the CdS shell. The correlation of photocatalytic activity with the shell thickness of Au-CdS nanocrystals corresponded well with that of the electron-transfer rate constant. As compared to the relevant commercial products like N-doped P-25 TiO 2 and CdS powders, the as-synthesized Au-CdS nanocrystals exhibited superior photocatalytic performance under visible light illumination, demonstrating their potential as an effective visible-light-driven photocatalyst. Furthermore, the result of performance evaluation under natural sunlight shows that the present Au-CdS nanocrystals can be used as highly efficient photocatalysts which may practically harvest energy from sunlight. © 2010 American Chemical Society.

Chang S.-C.,National Taiwan Ocean University | Chan T.-Y.,National Taiwan Ocean University | Ahyong S.T.,College Street
Journal of Crustacean Biology | Year: 2014

Specimens of species closely related to the rare deep-sea lobster Thaumastocheles japonicus Calman, 1913 were obtained from recent deep-sea expeditions in the West Pacific. Close examination of these specimens, as well as molecular analysis, showed that they represent two species new to science, with many morphological and significant genetic differences (barcoding gene COI sequence divergences 11.5-14.8%) between each other as well as T. japonicus. Re-examination of the specimens previously assigned to T. japonicus revealed that true T. japonicus has a more northern distribution, from Japan to the South China Sea and the Philippines. The two new species have more southern distributions with T. bipristis n. sp. restricted to the Philippines and Indonesia, and T. massonktenos n. sp. being widely distributed in the Indo-West Pacific, from the South China Sea to Madagascar and New Caledonia. The genetic data also suggest that T. dochmiodon Chan and de Saint Laurent, 1999 may represent a polymorphic male form of T. japonicas. © The Crustacean Society, 2014. Published by Brill NV, Leiden.

Lin C.-K.,National Taiwan Ocean University | Yu J.-T.,National Taiwan University | Lai Y.-S.,National Taipei University of Technology | Yu H.-C.,National Taiwan Ocean University
IEEE Transactions on Industrial Electronics | Year: 2016

An improved model-free predictive current control (IMFPCC) method for synchronous reluctance motor (SynRM) drives is presented in this paper. The main advantages of previous MFPCC are that it does not require specific SynRM models and it requires neither motor parameters nor back-EMF estimations. However, this approach has two disadvantages: 1) two current measurements are required in each sampling period, which may lead to the detection of undesirable current spikes caused by instantaneous switching inside the inverter, and 2) an unresolved problem of stagnant current-variation updates, which undermines the prediction performance. This paper intends to eliminate these two drawbacks while retaining all the merits of MFPCC. The proposed IMFPCC is simple and easy to realize. Furthermore, no pulsewidth modulation (PWM) technique is required. A 32-bit microprocessor, TMS320F2809, is utilized to implement both the proposed IMFPCC and the model-based predictive current control (MBPCC) for a performance comparison. Experiment results are provided to validate the proposed method and verify its feasibility. © 2016 IEEE.

Teng J.-Y.,Huafan University | Huang W.-C.,Kainan University | Lin M.-C.,National Taiwan Ocean University
Transportation | Year: 2010

It has always been a daunting task for any government to allocate the budgets for public infrastructure effectively so as to maximize the benefits of the limited resources. The most important contribution this paper makes is to conduct an empirical study of the budget allocations of the six region-based road system construction plans in northern Taiwan using the transportation budget allocation model devised in this paper. After reviewing the results, the experts consulted while preparing this paper believe that these results are both objective and able to meet the actual requirements. The competent authority also believes that they are better than those obtained using their original approach. In particular, the construction of this model takes into consideration the highest-level supervisors. To a certain degree, it caters for the practices in budget allocation so that the managers are able to assume the authority corresponding to their responsibility concerning management efficiency and final outcomes. © Springer Science+Business Media, LLC. 2009.

Yu M.-M.,National Taiwan Ocean University | Ting S.-C.,National Taiwan Ocean University | Chen M.-C.,National Chiao Tung University
Expert Systems with Applications | Year: 2010

Supply chain management integrates the intra- and inter-corporate processes as a whole system. Through information technology, companies can efficiently manage the product flow and information related to the issues such as production capacity, customer demand and inventory at lower costs. Information sharing can significantly improve the performance of the supply chain, how the different combination of information sharing affects the performance is not yet understood. This study designs different information-sharing scenarios to analyze the supply chain performance through a simulation model. Since there are not only desirable measures but also undesirable measures in supply chains, the usual data envelopment analysis (DEA) model allows measuring performance for complete weight flexibility. In this paper, a cross-efficiency DEA approach is applied to solve this problem. We identify the most efficient scenario and estimate the each efficiency of information-sharing scenarios. Contrary to the previous findings in the literature suggesting sharing as much as information possible to increase benefits, the results of this study show that the scenario of demand information sharing is the most efficient one. In addition, sharing information on capacity and demand, and full information sharing in general are good practices. Sharing only information on capacity and/or inventory information, without sharing information on demand, interferes with production at manufacturers, and causes misunderstandings, which can magnify the bullwhip effect. © 2009 Elsevier Ltd. All rights reserved.

Tsai W.-S.,National Chi Nan University | Lee K.-L.,Academia Sinica, Taiwan | Pan M.-Y.,Academia Sinica, Taiwan | Pan M.-Y.,National Tsing Hua University | And 3 more authors.
Optics Letters | Year: 2013

Increased detection sensitivity was achieved by adjusting the incident angle on periodic gold nanostructures that induced a resonant coupling between surface and substrate surface plasmon modes. For 500 nm-period gold nanoslits, a small incident angle, 7°, resulted in 2.64 times narrower linewidth and a 1.8 times increase in the figure of merit as compared to normal incidence. Furthermore, the intensity sensitivity was increased 4.5 times due to the change in the resonant coupling and redshift of the surface plasmon mode. © 2013 Optical Society of America.

Chang M.T.,National Chiao Tung University | Liang H.C.,National Taiwan Ocean University | Su K.W.,National Chiao Tung University | Chen Y.F.,National Chiao Tung University
Optics Express | Year: 2015

The dependence of lasiNg threshold on the output transmission is numerically analyzed to find the condition for the gain-to-loss balance for the orthogonal Np and Nm polarizations with a Ng-cut Yb:KGW laser crystal. With the numerical analysis, an orthogonally polarized dual-comb selfmode- locked operation is experimentally achieved with a coated Yb:KGW crystal to form a monolithic cavity. At a pump power of 5.2 W, the average output power, the pulse repetition rate, and the pulse duration are measured to be 0.24 (0.6) W, 25.8 (25.3) GHz, and 1.06 (1.12) ps for the output aloNg the Np (Nm) polarization. © 2015 Optical Society of America.

Yeh Y.-C.,National Central University | Yeh Y.-C.,University of Hawaii at Manoa | Sibuet J.-C.,National Taiwan Ocean University | Hsu S.-K.,National Central University | Liu C.-S.,National Taiwan University
Journal of Geophysical Research: Solid Earth | Year: 2010

We interpret a grid of 2-D seismic reflection profiles to resolve the tectonic evolution of the northeastern South China Sea (SCS), identifying two significant postbreakup events, T1 and T2, which occurred before the end of the SCS opening. In the absence of the drilling data in the deep basin, we date these two events using the identification of the magnetic anomalies, the age of major unconformities at Ocean Drilling Program Site 1148 drilled on the northeastern SCS margin, and the age of basalt samples in the deep SCS. The tectonic phase T1 is a slight tensional tectonic event which occurred in the deep SCS, south of the Luzon-Ryukyu Transform Plate Boundary (LRTPB). It is characterized by oceanic tilted blocks and fan-shaped deposits, which developed 8-10 Myr after the onset of SCS seafloor spreading (37.8 Ma). It corresponds to the first ENE-WSW to E-W change in spreading direction, which occurred around chron C10 (∼28.7 Ma). Event T2 is a magmatic phase observed in the deep SCS, south of the LRTPB. It is characterized by the uplift of former spreading features caused by an early Miocene (∼22 Ma) magmatic phase, which is also recorded in north and south-central Taiwan. Copyright © 2010 by the American Geophysical Union.

Lin F.-P.,National Taiwan Ocean University | Ho Y.-H.,National Taiwan Ocean University | Lin H.-Y.,U.S. Food and Drug Administration | Lin H.-J.,National Taiwan Ocean University
Extremophiles | Year: 2012

The smallest and enzymatically active molecule, TetApuQ818, was localized within the C-terminal Q818 amino acid residue after serial C-terminal truncation analysis of the recombinant amylopullulanase molecule (TetApuM955) from Thermoanaerobacter pseudoethanolicus. Kinetic analyses indicated that the overall catalytic efficiency, k cat/K m, of TetApuQ818 was 8-32% decreased for the pullulan and the soluble starch substrate, respectively. Changes to the substrate affinity, K m, and the turnover rate, k cat, were decreased significantly in both enzymatic activities of TetApuQ818. TetApuQ818 exhibited less thermostability than TetApuM955 when the temperature was raised above 85°C, but it had similar substrate-binding ability and hydrolysis products toward various substrates as TetApuM955 did. Both enzymes showed similar spectroscopies of fluorescence and circular dichroism, suggesting the active folding conformation was maintained after this C-terminal Q818 deletion. This study suggested that the binding ability of insoluble starch by TetApuM955 did not rely on the putative C-terminal carbohydrate binding module family 20 (CBM20) and two FnIII regions of TetApu, though the integrity of the AamyC module of TetApuQ818 was required for the enzyme activity. © 2012 Springer.

Tsai W.-S.,National Chi Nan University | Ting S.-Y.,National Chi Nan University | Wei P.-K.,Academia Sinica, Taiwan | Wei P.-K.,National Taiwan Ocean University
Optics Express | Year: 2012

The evanescent tails of a guiding mode as well as its first and second derivatives were measured by a modified end-fire coupling method. The effective index of the waveguide can be obtained by simultaneously fitting these three fields using single parameter. Combined with an inverse calculation algorithm, the fields with fitted evanescent tails showed great improvement in the refractive index profiling of the optical waveguide, especially at the substrate region. Single-mode optical fibers and planar waveguides of proton-exchanged (PE) and titanium-indiffusion (Ti:LiNbO3) on lithium niobate substrates with different refractive index profiles were measured for the demonstration. © 2012 Optical Society of America.

Chang C.-H.,National Chiao Tung University | Chang C.-H.,Academia Sinica, Taiwan | Tsai C.-L.,Endemic Species Research Institute | Jang-Liaw N.-H.,National Taiwan Ocean University
Mitochondrial DNA | Year: 2013

We describe the complete mitochondrial genome sequence of the Chinese rasbora, Rasbora steineri, which is a small cyprinid distributed in southeastern Asia. The circle genome (16,530 bp) consists of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and 1 control region. It has the typical vertebrate mitochondrial gene arrangement. © 2013 Informa UK, Ltd.

Lin W.-H.,National Tsing Hua University | Lin M.-Y.,National Taiwan University | Wu S.-Y.,National Tsing Hua University | Lin S.-Y.,Academia Sinica, Taiwan | And 2 more authors.
IEEE Photonics Technology Letters | Year: 2012

The influence of Sb/background As flux ratios on GaSb nano-structures is investigated in this letter. With decreasing Sb/background As flux ratios under high Sb irradiation during the post soaking procedure, ring formation, photoluminescence (PL) intensity enhancement, and PL peak red shift are observed. With further reduced Sb flux and Sb/background As ratios, the observed more intense PL intensities of the quantum-ring (QR) samples compared with quantum dots suggest that more electron-hole wave function overlapping is obtained. The observation of room-temperature electro-luminescence of a QR PIN diode has revealed the potential of the nano-structure in light-emitting device application. © 2012 IEEE.

Yeh Y.-M.,Nanhua University | Huang H.-W.,National Taiwan Ocean University | Melvin E.,University of Washington
Animal Conservation | Year: 2013

Read the Commentaries on this Feature Paper: Finding the missing pieces: working to solve the fisheries bycatch puzzle; Next step for reducing seabird bycatch; Requisite improvements to the estimation of seabird by-catch in pelagic longline fisheries Response from the authors: Incidental catch of seabirds: strengthening observer programs and increasing cooperation The mortality of seabirds in fisheries has had a serious negative impact on many seabird populations, yet the extent of fishery-derived seabird mortality in pelagic longline fisheries, remains poorly understood. In this study, we analyze fishing effort and catch data of the Taiwanese distant-water longline tuna fleet - the largest fleet in the Atlantic Ocean. These data collected by fishery observers over a 5-year span include 61 trips involving 6181 observed sets of over 20 million hooks, where 198 seabirds were caught (23 of which were released alive). Most birds were caught in the South Atlantic, with estimated seabird bycatch rates ranging from 0.026 birds per thousand hooks in the southwest Atlantic to 0.063 birds per thousand hooks in the southeast Atlantic. Black-browed, Atlantic yellow-nosed, and wandering albatrosses, as well as spectacled and southern giant petrels, were the most frequently caught species. Seabird bycatch hotspots were identified at 20°-40°S/10°W-15°E and 35°-45°S/45°-55°W. In the South Atlantic Ocean, generalized additive models indicated that fishing location and the number of birds sighted significantly influenced seabird bycatch rates. Extrapolating these spatially and temporally explicit seabird bycatch rates to the fishing effort data of other distant-water longline fleets and extrapolating the bycatch rates reported in the literature to the reported fishing effort of coastal nation fleets, we estimate the total seabird incidental mortality from pelagic longline fishing in the southern Atlantic Ocean to be between 3446 and 6083 birds per year from 2004 to 2008. These findings support proposals calling for the required use of best-practice mitigation measures by all pelagic longline vessels operating in seabird bycatch hotspots in the South Atlantic Ocean. International cooperation on research and data sharing is critical to ensure the sustainability of seabird populations and fisheries. © 2012 The Authors. Animal Conservation © 2012 The Zoological Society of London.

Wang K.,National Chiao Tung University | Huang C.-Y.,National Taiwan Ocean University | Lin S.-J.,National Chiao Tung University | Lin Y.-D.,National Chiao Tung University
Computer Networks | Year: 2011

Botnet has become a popular technique for deploying Internet crimes. Although signature-based bot detection techniques are accurate, they could be useless when bot variants are encountered. Therefore, behavior-based detection techniques become attractive due to their ability to detect bot variants and even unknown bots. In this paper, we propose a behavior-based botnet detection system based on fuzzy pattern recognition techniques. We intend to identify bot-relevant domain names and IP addresses by inspecting network traces. If domain names and IP addresses used by botnets can be identified, the information can be further used to prevent protected hosts from becoming one member of a botnet. To work with fuzzy pattern recognition techniques, we design several membership functions based on frequently observed bots' behavior including: (1) generate failed DNS queries; (2) have similar DNS query intervals; (3) generate failed network connections; and (4) have similar payload sizes for network connections. Membership functions can be easily altered, removed, or added to enhance the capability of the proposed system. In addition, to improve the overall system performance, we develop a traffic reduction algorithm to reduce the amount of network traffic required to be inspected by the proposed system. Performance evaluation results based on real traces show that the proposed system can reduce more than 70% input raw packet traces and achieve a high detection rate (about 95%) and a low false positive rates (0-3.08%). Furthermore, the proposed FPRF algorithm is resource-efficient and can identify inactive botnets to indicate potential vulnerable hosts. © 2011 Elsevier B.V. All rights reserved.

Chang L.,National Taiwan Ocean University | Chang Y.-L.,National Taipei University of Technology | Tang Z.S.,National Taiwan Ocean University | Huang B.,University of Wisconsin - Madison
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing | Year: 2011

In this study, a novel group and region based parallel compression approach is proposed for hyperspectral imagery. The proposed approach contains two algorithms, which are clustering signal subspace projection (CSSP) and the maximum correlation band clustering (MCBC). The CSSP first divides the image into proper regions by transforming the high dimensional image data into one dimensional projection length. The MCBC partitions the spectral bands into several groups according to their associated band correlation for each image region. The image data with high degree correlations in spatial/spectral domains are then gathered in groups. Then, the grouped image data is further compressed by Principal Components Analysis (PCA)-based spectral/spatial hyper-spectral image compression techniques. Furthermore, to accelerate the computing efficiency, we present a parallel architecture of the proposed compression approach by using parallel cluster computing techniques. Simulation results performed on AVIRIS images have shown that the proposed group and region based approach performs better than standard 3D hyperspectral image compression. Moreover, the proposed approach achieves better computation efficiency than the direct combination of PCA and JPEG2000 under the same compression ratio. © 2011 IEEE.

Tsai F.,National Taiwan Ocean University | Liu T.-H.,National Central University
Atmospheric Environment | Year: 2013

A three-dimensional photochemistry model is applied to analyze three unusual high O3 episodes that occurred continuously in Taiwan from May 1 to 11, 2007. During this period, the first high ozone episode was observed in northern and central western Taiwan on May 4. Following this episode, the second episode was observed throughout Taiwan on May 7, and continued for several days until May 10, when the third episode was observed in central western and southwestern Taiwan. This was the worst O3 period in Taiwan over the past two decades. During this period, 70% of the local air quality station reported an O3 concentration of over 120ppb, and a maximum O3 concentration of 175ppb was observed in background Taiwan. Based on model analyses, the sources of the three high O3 episodes differ. The high O3 concentration observed during the first episode is mainly attributed to the northeastward transport of O3 precursors and concentrations from northern and central western Taiwan under southwesterlies prior to frontal passage, chemically producing O3 over 30ppbh-1 in northern Taiwan. During the second episode, horizontal advection of Asian outflow during the passage of an anticyclone and front contributes a maximum of 25ppbh-1 in both northern and southern tip of Taiwan, respectively, increasing to more than 75ppbh-1 in southwestern Taiwan because of the combination with the local source. During the third episode when the prevailing easterlies associated with a departing anticyclone to the east of Taiwan is blocked by the high central mountain, local O3 chemical production and horizontal transport contribute a maximum of 25ppbh-1 and 35ppbh-1 in central and southwestern Taiwan, respectively, under a calm and high background O3 condition. Source from Taiwan contributes more than half of the high O3 concentration over northwestern Taiwan prior to frontal passage during the first episode, but decreases to mostly below 40% over western Taiwan during the second episode when Asian outflow occurs, and increases to more than 60% over central and southwestern Taiwan due to pollution accumulation under an anticyclonic departure. © 2013 Elsevier Ltd.

Tseng C.-M.,National Taiwan University | Liu K.-K.,National Central University | Gong G.-C.,National Taiwan Ocean University | Shen P.-Y.,National Taiwan University | Cai W.-J.,University of Georgia
Geophysical Research Letters | Year: 2011

Limited knowledge exists concerning the unusually large CO 2 uptake capacity in the East China Sea (ECS), which is the eminent continental shelf pump for efficient transfer of atmospheric CO 2 to the deep ocean. Here we show evidence of strong control of river runoff on the CO 2 uptake capacity of the ECS. From 8-years of observations in the productive ECS shelf, we present the first dataset to show the complete seasonal cycle of CO 2 flux, which gives an annual flux of 2.3 ± 0.4 mol C m -2 y -1 as a net sink of atmospheric CO 2. Further, we found biological sequestration of CO 2 taking place in the highly productive Changjiang river plume in warm seasons due to the riverine nutrient enrichment. Consequently, changes in the plume area due to changes in the Changjiang River Discharge (referred to as the Discharge hereafter) strongly affect the CO 2 uptake capacity. As the Discharge may decrease due to the Three Gorges Dam operation, the Changjiang plume will probably also decrease, resulting in reduction in CO 2 uptake capacity and even a shift from a CO 2 sink to a source. Copyright 2011 by the American Geophysical Union.

Lan K.-W.,National Taiwan Ocean University | Evans K.,CSIRO | Lee M.-A.,National Taiwan Ocean University
Climatic Change | Year: 2013

Variations in the abundance and distribution of pelagic tuna populations have been associated with large-scale climate indices such as the Southern Oscillation Index in the Pacific Ocean and the North Atlantic Oscillation in the Atlantic Ocean. Similarly to the Pacific and Atlantic, variability in the distribution and catch rates of tuna species have also been observed in association with the Indian Ocean Dipole (IOD), a basin-scale pattern of sea surface and subsurface temperatures that affect climate in the Indian Ocean. The environmental processes associated with the IOD that drive variability in tuna populations, however, are largely unexplored. To better understand these processes, we investigated longline catch rates of yellowfin tuna and their distributions in the western Indian Ocean in relation to IOD events, sea surface water temperatures (SST) and estimates of net primary productivity (NPP). Catch per unit effort (CPUE) was observed to be negatively correlated to the IOD with a periodicity centred around 4 years. During positive IOD events, SSTs were relatively higher, NPP was lower, CPUE decreased and catch distributions were restricted to the northern and western margins of the western Indian Ocean. During negative IOD events, lower SSTs and higher NPP were associated with increasing CPUE, particularly in the Arabian Sea and seas surrounding Madagascar, and catches expanded into central regions of the western Indian Ocean. These findings provide preliminary insights into some of the key environmental features driving the distribution of yellowfin tuna in the western Indian Ocean and associated variability in fisheries catches. © 2012 The Author(s).

Chou W.-C.,National Taiwan Ocean University | Gong G.-C.,National Taiwan Ocean University | Gong G.-C.,Taiwan Ocean Research Institute | Hung C.-C.,National University of Kaohsiung | Wu Y.-H.,National Taiwan Ocean University
Biogeosciences | Year: 2013

To assess the impact of rising atmospheric CO2 and eutrophication on the carbonate chemistry of the East China Sea shelf waters, saturation states (Ω) for two important biologically relevant carbonate minerals-calcite (Ωc) and aragonite (Ωa)-were calculated throughout the water column from dissolved inorganic carbon (DIC) and total alkalinity (TA) data collected in spring and summer of 2009. Results show that the highest Ωc (∼9.0) and Ωa (∼5.8) values were found in surface water of the Changjiang plume area in summer, whereas the lowest values (Ωc Combining double low line ∼2.7 and Ωa Combining double low line ∼1.7) were concurrently observed in the bottom water of the same area. This divergent behavior of saturation states in surface and bottom waters was driven by intensive biological production and strong stratification of the water column. The high rate of phytoplankton production, stimulated by the enormous nutrient discharge from the Changjiang, acts to decrease the ratio of DIC to TA, and thereby increases Ω values. In contrast, remineralization of organic matter in the bottom water acts to increase the DIC to TA ratio, and thus decreases Ω values. The projected result shows that continued increases of atmospheric CO2 under the IS92a emission scenario will decrease Ω values by 40-50% by the end of this century, but both the surface and bottom waters will remain supersaturated with respect to calcite and aragonite. Nevertheless, superimposed on such Ω decrease is the increasing eutrophication, which would mitigate or enhance the Ω decline caused by anthropogenic CO2 uptake in surface and bottom waters, respectively. Our simulation reveals that, under the combined impact of eutrophication and augmentation of atmospheric CO2, the bottom water of the Changjiang plume area will become undersaturated with respect to aragonite (Ωa Combining double low line ∼0.8) by the end of this century, which would threaten the health of the benthic ecosystem. © 2013 Author(s).

Lee H.-J.,National Taiwan Ocean University | Liu K.-K.,National Central University
Journal of Marine Science and Technology (Taiwan) | Year: 2013

We incorporated tidal currents into a previously validated three-dimensional subtidal circulation model, and used it to assess the manner in which tides affect the Changjiang plume dispersal. The coupled model results show that competition in both tidal and wind-driven currents occurs during the winter season. However, the northeasterly winds are predominant in the competition because they transport large amounts of brackish water to the south along the southeastern China coast. In general, the summer tidal currents disperse Changjiang plume more southward and seaward rather than northward for the case without tides; however, the winter tidal currents seem to reduce their effects. In winter, the tidal currents may cause strong turbulent tidal mixing with their ambient water, particularly close to the coastal boundaries. Thus, results more closely aligned with observations of Changjiang River plumes were obtained from the tide-circulated coupling model than from the general circulation model.

Chou C.-C.,National Taiwan Ocean University | Wu Y.-Y.,National Taiwan Ocean University | Lee J.-W.,Ming Chi University of Technology | Yeh C.-H.,Chang Gung Memorial Hospital | Huang J.-C.,Tungnan University
Surface and Coatings Technology | Year: 2013

Fluorinated diamond-like carbon (F-DLC) films were deposited on Ti6Al4V substrates by radio frequency plasma enhanced chemical vapor deposition (rf PECVD) technique using a mixture of methane (CH4) and tetrafluoromethane (CF4) gasses. A 100nm Si interlayer was coated in advance by physical vapor deposition (PVD) to improve the adhesion between F-DLC and Ti alloy. A 200nm TiN-coated specimen with the same Ti6Al4V substrate was also built by PVD as a benchmark. The structure and surface properties of F-DLC coatings, prepared with various fluorine flow ratios, were investigated by using X-ray photoelectron spectroscopy, scanning electron microscopy, atomic force microscopy, liquid drop goniometry, and electrochemical corrosion tests. The blood compatibility was evaluated by measuring haemolysis ratio and platelet-covered area in vitro. The films' spectroscopic results show that the CFx group and fluorine atomic concentration increase as CF4 flow ratio is promoted in the mixture. The surface energy is reduced due to the increased fluorine content. The modified surfaces are characterized by higher hydrophobicity, lower thrombogenicity, and better corrosive protection than the virgin and TiN ones. © 2012 Elsevier B.V.

Peng S.-H.,National University of Kaohsiung | Hung J.-J.,National University of Kaohsiung | Hwang J.-S.,National Taiwan Ocean University
Marine Pollution Bulletin | Year: 2011

The concentrations of ten trace metals were determined in the gills, muscles, hepatopancreas, and exoskeleton tissues of Xenograpsus testudinatus that lives around shallow and acidic hydrothermal vents off Kueishan Island, northeastern Taiwan. The analytical results demonstrate that the metal concentrations vary significantly with the type of crab tissue. The concentrations of Al, Cd, Co, Cu, Fe, Ni, and Zn are highest in the gills, whereas the concentration of Mn is highest in the exoskeleton. Cr and Pb concentrations are similar across the different tissues. The enhanced accumulation of most metals in the gills suggests the metal accumulation via the respiration pathway rather than the uptake of food. The results also reveal that the distribution patterns of metals in tissues are similar in the hepatopancreas and muscles, but very different in both the gills and the exoskeleton, perhaps because of the different pathways of metal utilization in the different crab tissues. © 2011 Elsevier Ltd.

Tang Y.-Y.,U.S. Food and Drug Administration | Tang Y.-Y.,National Taiwan Ocean University | Lu H.-F.,U.S. Food and Drug Administration | Lin H.-Y.,U.S. Food and Drug Administration | And 2 more authors.
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences | Year: 2012

An ultraperformance liquid chromatography-electrospray tandem mass spectrometry (UPLC-MS/MS) method for the simultaneous detection and confirmation of 23 veterinary (multiclass) drugs in milk was developed and validated. The analytes were extracted by acetonitrile, evaporated and injected into the UPLC-MS/MS system on a Waters UPLC HSS T3 column in gradient mode. Data acquisition under MS/MS was achieved by applying multiple reaction monitoring (MRM) of two ion transitions per compound to provide a high degree of specificity. Results showed good repeatability, and recoveries for the 12 macrolide, 7 β-lactam and 2 lincosamide antibiotics and 2 other veterinary drugs (morantel, orbifloxacin) used in milk averaged 51.8-139.0%, 51.5-100.6%, 82.4-102.5% and 87.5-99.4%, respectively. The coefficients of variation (C.V.) of the recoveries were less than 15% for intraday and interday precisions. The limits of quantification (LOQs) were all lower than 5. ng/ml. This method was applied to 17 fresh milk samples and only lincomycin was found in milk samples under allowable levels. Overall, this method is a suitable and rapid tool to confirm the presence of 23 veterinary drug residues in milk. © 2011.

Yang M.-F.,National Taiwan Ocean University | Lin Y.,National Taipei University of Technology
European Journal of Industrial Engineering | Year: 2012

Nowadays, supply chain management (SCM) is a popular practice in manufacturing systems. The concept of SCM has forced members to find ways to cut costs and bring performance benefits to the firms. In the creation of long-term partnerships in the supply chain, the collaboration between supply chain partners for improving the performance of inventory control is of special interest. This paper develops a single-vendor multiple-buyer integrated inventory model for minimising the total relevant annual costs incurred by the vendor and the buyers while the probability distribution of the lead time demand is normal, and the option of investing in process quality improvement is included. Copyright © 2012 Inderscience Enterprises Ltd.

Kirschner R.,National Central University | Pang K.-L.,National Taiwan Ocean University | Jones E.B.G.,University of Malaya
Mycological Progress | Year: 2013

Based on own collections, two species of cheirosporous hyphomycetes (anamorphic Pleosporales) have been reexamined by morphology and molecular analysis. Cheiromyces inflatus is a new record for England. Transfers of Ch. inflatus to Dictyosporium and of Cheiromoniliophora elegans to Pseudodictyosporium are proposed. © 2012 German Mycological Society and Springer.

Jwo D.-J.,National Taiwan Ocean University | Cho T.-S.,National Chi Nan University
Measurement: Journal of the International Measurement Confederation | Year: 2010

The Kalman filter has been used in a wide variety of engineering applications. There are two typical forms in implementing the nonlinear Kalman filter in conjunction with linearisation trajectory for which calculation of Jacobian matrices is involved: the linearised Kalman filter (LKF) and the extended Kalman filter (EKF). This paper aims to serve as a tutorial to the readers for providing better understanding and correctly implementing the two forms of nonlinear filters. Some critical remarks useful in designing a nonlinear Kalman filter are pointed out. Linearisation of the trajectory for the LKF and EKF is discussed. Performance degradation due to linearisation error is illustrated. Divergence problem for the LKF is presented. Implementation practice for the LKF and the EKF via total state estimate in conjunction with the error state estimate (in which the state variables are incremental quantities) are provided. Discussion on increase of dynamic process noise to the estimation precision in LKF and EKF is involved. Clear description of the implementation algorithms is provided. The step-by-step procedure for performing the filters is provided accompanied with two geodetic navigation examples. The materials prepared in this paper can be modified for further development in various applications. © 2010 Elsevier Ltd. All rights reserved.

Durand J.D.,Montpellier University | Blel H.,University of Monastir | Shen K.N.,National Taiwan Ocean University | Koutrakis E.T.,Greek National Agricultural Research Foundation | Guinand B.,Montpellier University
Marine Ecology Progress Series | Year: 2013

The population structure and evolutionary history of Mugil cephalus were investigated across 18 sampling sites in the NE Atlantic Ocean, Mediterranean and Black Seas, using 2 classes of genetic markers: sequence polymorphism of an 857 bp fragment of mitochondrial (mtDNA) cytochrome b, and allele size variation at 7 nuclear loci. The level of nucleotide diversity recovered with the mtDNA marker was very low (~0.6% divergence), indicating the presence of a single clade over the entire area. Mismatch distribution, Bayesian skyline plots and associated statistics revealed a recent demographic crash followed by population expansion, but nuclear data indicated population constancy in the area covered in this study. While a single clade was detected, significant mtDNA genetic differentiation was, however, observed between the samples from the Black Sea and the samples from other (sub-) basins (φST = 0.17; p = 0.029). The nuclear loci also revealed significant genetic differentiation and isolation-by-distance in M. cepha lus. Patterns of genetic structure were, however, significantly more pronounced with nuclear than with mtDNA markers; the former indicated the presence of 3 (Bayesian clustering) to 6 (Monmonnier's method) populations. The highest levels of genetic heterogeneity at nuclear markers occurred at the wellknown Almeria-Oran Front, but also in the Bosporus Strait. Thus, both sets of markers revealed the importance of this strait as a barrier to gene flow, probably during the Pleistocene. The results also revealed genetic heterogeneity in the eastern Mediterranean basin, and suggested that the population expanded from this sub-basin towards the Atlantic Ocean and Black Sea. © Inter-Research 2013.

Leu M.-Y.,National Museum of Marine Biology and Aquarium | Leu M.-Y.,National Dong Hwa University | Liou C.-H.,National Taiwan Ocean University
Journal of the Marine Biological Association of the United Kingdom | Year: 2013

The larval development of the Russell's snapper Lutjanus russellii is described and illustrated for the first time. Fertilized eggs, with a mean diameter of 0.80 ± 0.04 mm and a range from 0.71 to 0.84 mm, were spherical, transparent, buoyant and unpigmented. Embryonic development lasted 26 hours 50 minutes at 24.7°C. Newly hatched larvae were 1.86 ± 0.10 mm in total length (TL) with 24 (10 + 14) myomeres and had an oil globule in the ventroanterior area of the yolk sac. Two days after hatching (DAH, 2.61 mm TL), the mouth opened. Early larvae had melanophores scattered on the head, body and yolk surface. Thirteen DAH (2.74 mm TL), the buds of the second dorsal and pelvic-fin spines had appeared. At 5.81 mm TL, the notochord was slightly flexed, and the hypural bones and caudal-fin rays had begun to develop. The ratios of the second dorsal and pelvic-fin spine lengths to TL attained their maximum, 40% and 36%, respectively. At 14.02 mm TL, all fins had the adult complement of rays and spines. The characteristic of this species, with four black stripes on the sides and with a round black spot on the upper back, was completed in juvenile of 23.1 mm TL. The larval habitat shifted from the surface and middle layers to the tank bottom. A statistical model: Y equals 2.18e 0.06 X, where Y is mean TL (mm) and X represents DAH, explained 99.34% of variation in growth (P < 0.001, R 2 = 0.9934). © Marine Biological Association of the United Kingdom 2013.

Doong D.-J.,National Taiwan Ocean University | Lee B.-C.,Huafan University | Kao C.C.,National Cheng Kung University
Sensors | Year: 2011

This study presents the idea of using GPS-output velocity signals to obtain wave measurement data. The application of the transformation from a velocity spectrum to a displacement spectrum in conjunction with the directional wave spectral theory are the core concepts in this study. Laboratory experiments were conducted to verify the accuracy of the inversed displacement of the surface of the sea. A GPS device was installed on a moored accelerometer buoy to verify the GPS-derived wave parameters. It was determined that loss or drifting of the GPS signal, as well as energy spikes occurring in the low frequency band led to erroneous measurements. Through the application of moving average skill and a process of frequency cut-off to the GPS output velocity, correlations between GPS-derived, and accelerometer buoy-measured significant wave heights and periods were both improved to 0.95. The GPS-derived one-dimensional and directional wave spectra were in agreement with the measurements. Despite the direction verification showing a 10° bias, this exercise still provided useful information with sufficient accuracy for a number of specific purposes. The results presented in this study indicate that using GPS output velocity is a reasonable alternative for the measurement of ocean waves. © 2011 by the authors.

Wang D.-H.,National Taiwan Ocean University | Chen C.-C.,Feng Chia University | Lai C.-S.,Keelung District Prosecutors Office
Journal of Transport Geography | Year: 2011

The Bunker Adjustment Factor (BAF) system was first introduced following the oil shocks of the 1970s. The underlying justification for such a system was that shipping lines operating in freight conferences could not otherwise adjust their prices promptly enough to counteract the devastating effect of bunker price increases. Thirty years after its imposition, BAF has always been a bone of contention between carriers and shippers. Ocean carriers contend that it is a necessary evil to reduce their exposure to volatile bunker price, while shippers argue that this risk should either be considered as a normal commercial venture, or dealt with in a more transparent way. When bunker surcharges began to climb in 2003, BAF disputes became one of the main obstacles to the dialog between both parties. To settle the dispute over BAF, the Europe Commission (EC) called for the submission on the issue of surcharges. The European Commission banned carrier conferences on October 17th 2008. The shipping lines now set their own independent BAF rates, which are closely monitored by the EC to ensure no collusion. The fluctuation in oil price in 2008 means that the BAF rates are now coming down, but there are still some wide variations in application. During this period of dramatic change in shipping environment, it has become important to provide a theoretical framework for analyzing the BAF. This paper focuses on examining the rationale behind and effects of BAF. A microeconomic model is made to explore the underlying mechanism of BAF. By examining the trade routes of Asia to Europe and Asia to North America during the period 2003-2008, this study finds the practice of BAF cushions an ocean carrier from the negative effects of bunker price fluctuations, and provides shipping lines a powerful tool to change the incentive structure facing carriers. Despite engineers showing that reducing the speed of vessels can economize fuel consumption evidence shows there has been little change by major shipping lines in their transit time and sailing schedules during the recent period of skyrocketing fuel price. It is apparent they use the BAF as the cushion against the effect of rising bunker prices. © 2009 Elsevier Ltd.

Hsu J.-C.,National Taiwan University of Science and Technology | Huang C.-C.,National Taiwan Ocean University | Ou K.-L.,Taipei Medical University | Lu N.,National Taipei University of Technology | And 3 more authors.
Journal of Materials Chemistry | Year: 2011

A strategy is presented for the synthesis of dual-modality and theranostic silica (SiO2) nanohybrids that exert excellent properties for drug delivery vehicles as well as optical and magnetic resonance imaging. SiO 2 nanohybrids are composed of CuInS2/ZnS quantum dots and magnetite nanocrystals, with an outside SiO2 shell grafted with poly(ethyleneglycol) and amine groups to provide better biocompatibility and allow subsequent bioconjugation, respectively. The synthesized nanohybrids are of ultra-small size (diameter < 30 nm) and highly monodispersed and stable in aqueous suspension. In vitro results showed that the SiO2 nanohybrids were efficiently taken up by the cells and localized in the intracellular vesicles, emitting strong fluorescence from the cytoplasm and nearby nucleus. It was also demonstrated that SiO2 nanohybrids could be used as a new class of magnetic resonance imaging probes, demonstrating a high spin-spin (T2) relaxivity (r2 = 214 mM-1 s-1). The Pt(iv) anticancer drug, c,c,t-[Pt(NH3) 2Cl2(O2CCH2CH2CO 2H)2], was used as a model drug to attach to the surface of dual-modality SiO2 nanohybrids by using n-ethyl-N′-(3- dimethylaminopropyl)carbodiimide and hydroxysuccinimide as the activating agents. The drug readily formed amide linkages with amines on the surface of the SiO2 nanohybrids, resulting in Pt(iv)-conjugated SiO2 nanohybrids. The results reveal that the Pt(iv)-conjugated SiO2 nanohybrids show higher cytotoxicity than the free Pt(iv) anticancer drug, indicating the potential for using the obtained multifunctional SiO2 nanohybrids simultaneously as highly effective dual-modality imaging probes for cancer diagnosis and chemotherapy. © 2011 The Royal Society of Chemistry.

Tu Y.-H.,National Central University | Ho Y.-H.,National Central University | Chuang Y.-C.,National Taiwan Ocean University | Chen P.-C.,National Central University | Chen C.-S.,National Central University
PLoS ONE | Year: 2011

Lactoferricin B (LfcinB) is a well-known antimicrobial peptide. Several studies have indicated that it can inhibit bacteria by affecting intracellular activities, but the intracellular targets of this antimicrobial peptide have not been identified. Therefore, we used E. coli proteome chips to identify the intracellular target proteins of LfcinB in a high-throughput manner. We probed LfcinB with E. coli proteome chips and further conducted normalization and Gene Ontology (GO) analyses. The results of the GO analyses showed that the identified proteins were associated with metabolic processes. Moreover, we validated the interactions between LfcinB and chip assay-identified proteins with fluorescence polarization (FP) assays. Sixteen proteins were identified, and an E. coli interaction database (EcID) analysis revealed that the majority of the proteins that interact with these 16 proteins affected the tricarboxylic acid (TCA) cycle. Knockout assays were conducted to further validate the FP assay results. These results showed that phosphoenolpyruvate carboxylase was a target of LfcinB, indicating that one of its mechanisms of action may be associated with pyruvate metabolism. Thus, we used pyruvate assays to conduct an in vivo validation of the relationship between LfcinB and pyruvate level in E. coli. These results showed that E. coli exposed to LfcinB had abnormal pyruvate amounts, indicating that LfcinB caused an accumulation of pyruvate. In conclusion, this study successfully revealed the intracellular targets of LfcinB using an E. coli proteome chip approach. © 2011 Tu et al.

Guiguen Y.,French National Institute for Agricultural Research | Fostier A.,French National Institute for Agricultural Research | Piferrer F.,CSIC - Institute of Marine Sciences | Chang C.-F.,National Taiwan Ocean University
General and Comparative Endocrinology | Year: 2010

The present review focuses on the roles of estrogens and aromatase (Cyp19a1a), the enzyme needed for their synthesis, in fish gonadal sex differentiation. Based on the recent literature, we extend the already well accepted hypothesis of an implication of estrogens and Cyp19a1a in ovarian differentiation to a broader hypothesis that would place estrogens and Cyp19a1a in a pivotal position to control not only ovarian, but also testicular differentiation, in both gonochoristic and hermaphrodite fish species. This working hypothesis states that cyp19a1a up-regulation is needed not only for triggering but also for maintaining ovarian differentiation and that cyp19a1a down-regulation is the only necessary step for inducing a testicular differentiation pathway. When considering arguments for and against, most of the information available for fish supports this hypothesis since either suppression of cyp19a1a gene expression, inhibition of Cyp19a1a enzymatic activity, or blockage of estrogen receptivity are invariably associated with masculinization. This is also consistent with reports on normal gonadal differentiation, and steroid-modulated masculinization with either androgens, aromatase inhibitors or estrogen receptor antagonists, temperature-induced masculinization and protogynous sex change in hermaphrodite species. Concerning the regulation of fish cyp19a1a during gonadal differentiation, the transcription factor foxl2 has been characterized as an ovarian specific upstream regulator of a cyp19a1a promoter that would co-activate cyp19a1a expression, along with some additional partners such as nr5a1 (sf1) or cAMP. In contrast, upstream factors potentially down-regulating cyp19a1a during testicular differentiation are still hypothetical, such as the dmrt1 gene, but their definitive characterization as testicular repressors of cyp19a1a would strongly strengthen the hypothesis that early testicular differentiation would need active repression of cyp19a1a expression. © 2009 Elsevier Inc. All rights reserved.

Lin C.-W.,National Museum of Marine Biology and Aquarium | Lin C.-W.,National Dong Hwa University | Chan T.-Y.,National Taiwan Ocean University
Zootaxa | Year: 2011

Two new deep-sea munidopsids, Munidopsis aurantia sp. nov. and M. laevisquama sp. nov., are described from Taiwan. Munidopsis aurantia sp. nov. closely resembles M. serricornis (Lovén, 1852), but differs in lacking an antennal spine, cheliped with fingers longer than palm and merus bearing distal spines but without a row of dorsal spines. Munidopsis laevisquama sp. nov. differs from other congeners by its carapace being densely covered with squamae but without dorsal spines, eyes that are subglobular and lacking spines or papillae, the basal antennal segment bearing a cylindrical process, and the cheliped and walking legs all lacking distal spines. Altogether 36 species of Munidopsis are now known from the deep waters off Taiwan. Copyright © 2011.

Wu S.-D.,National Taiwan Normal University | Wu C.-W.,National Taiwan Normal University | Lin S.-G.,National Taiwan Ocean University | Lee K.-Y.,National Taiwan University | And 2 more authors.
Physics Letters, Section A: General, Atomic and Solid State Physics | Year: 2014

Multiscale entropy (MSE) is an effective algorithm for measuring the complexity of a time series that has been applied in many fields successfully. However, MSE may yield an inaccurate estimation of entropy or induce undefined entropy because the coarse-graining procedure reduces the length of a time series considerably at large scales. Composite multiscale entropy (CMSE) was recently proposed to improve the accuracy of MSE, but it does not resolve undefined entropy. Here we propose a refined composite multiscale entropy (RCMSE) to improve CMSE. For short time series analyses, we demonstrate that RCMSE increases the accuracy of entropy estimation and reduces the probability of inducing undefined entropy. © 2014 Elsevier B.V.

Yao W.-H.,National Central University | Tung P.-C.,National Central University | Fuh C.-C.,National Taiwan Ocean University | Chou F.-C.,National Central University
IEEE Transactions on Industrial Electronics | Year: 2013

This paper presents the suppression of hunting in an ironless linear permanent-magnet synchronous motor (ILPMSM) driver system using a hunting compensator. In high-precision motion control servo systems, hunting induced by nonlinear elements such as friction and saturation will reduce the system performance. Hunting means that limit cycle occurs in the system, causing a series of sustained oscillations. The hunting compensator is designed based on the circle criterion to ensure system stability. The effectiveness of the proposed control scheme is verified by simulation and experimental results. The proposed algorithm is experimentally tested on an ILPMSM drive system, and the experimental results confirm the ability of the hunting compensation scheme to suppress the effects of hunting. © 1982-2012 IEEE.

Yang M.-F.,National Taiwan Ocean University | Lin Y.,National Taipei University of Technology
Computers and Industrial Engineering | Year: 2013

The aim of this paper is to develop an interactive two-phase method that can help the Project Manager (PM) with solving the fuzzy multi-objective decision problems. Therefore, in this paper, we first revisit the related papers and focus on how to develop an interactive two-phase method. Next, we establish to consider the imprecise nature of the data by fulfilling the possibilistic programming model, and we also assume that each objective work has a fuzzy goal. Finally, for reaching our objective, the detailed numerical example is presented to illustrate the feasibility of applying the proposed approach to PM decision problems at the end of this paper. Results show that our model can be applied as an effective tool. Furthermore, we believe that this approach can be applied to solve other multi-objective decision making problems. © 2013 Elsevier Ltd. All rights reserved.

Chou W.-C.,National Taiwan Ocean University | Gong G.-C.,National Taiwan Ocean University | Tseng C.-M.,National Taiwan University | Sheu D.D.,National Sun Yat - sen University | And 3 more authors.
Marine Chemistry | Year: 2011

Measurements of dissolved inorganic carbon (DIC), pH, total alkalinity (TA), and partial pressure of CO2 (pCO2) were conducted at a total of 25 stations along four cross shelf transects in the East China Sea (ECS) in January 2008. Results showed that their distributions in the surface water corresponded well to the general circulation pattern in the ECS. Low DIC and pCO2 and high pH were found in the warm and saline Kuroshio Current water flowing northeastward along the shelf break, whereas high DIC and pCO2 and low pH were mainly observed in the cold and less saline China Coastal Current water flowing southward along the coast of Mainland China. Difference between surface water and atmospheric pCO2 (δpCO2), ranging from ~0 to -111μatm, indicated that the entire ECS shelf acted as a CO2 sink during winter with an average flux of CO2 of -13.7±5.7 (mmolCm-2day-1), and is consistent with previous studies. However, pCO2 was negatively correlated with temperature for surface waters lower than 20°C, in contrast to the positive correlation found in the 1990s. Moreover, the wintertime -pCO2 in the inner shelf near the Changjiang River estuary has appreciably decreased since the early 1990s, suggesting a decline of CO2 sequestration capacity in this region. However, the actual causes for the observed relationship between these decadal changes and the increased eutrophication over recent decades are worth further study. © 2010 Elsevier B.V.

Chang M.-H.,National Taiwan Ocean University | Lien R.-C.,University of Washington | Tang T.Y.,National Taiwan University
Journal of Atmospheric and Oceanic Technology | Year: 2011

A method is developed to estimate nonlinear internal wave (NLIW) vertical displacement, propagation direction, and propagation speed from single moored acoustic Doppler current profiler (ADCP) velocity observations. The method is applied to three sets of bottom-mounted ADCP measurements taken on the continental slope in the South China Sea in 2006-07. NLIW vertical displacement is computed as the time integration of ADCP vertical velocity observations corrected with the vertical advection of the background flow by the NLIW. NLIW vertical currents displace the background horizontal current and shear by~150 m. NLIW propagation direction is estimated as the principal direction of the wave-induced horizontal velocity vector, and propagation speed is estimated using the continuity equation in the direction of wave propagation, assuming the wave's horizontal spatial structure and propagation speed remain constant as the NLIW passes the mooring, typically O(10 min). These NLIW properties are estimated simultaneously and iteratively using the ADCP velocity measurements, corrected for their beam-spreading effect. In most cases, estimates converge to within 3% after four iterations. The proposed method of extracting NLIW properties from velocity measurements is confirmed using NLIWs simulated by the fully nonlinear Dubreil-Jacotin-Long model. Estimates of propagation speed using the ADCP velocity measurements are also in good agreement with those calculated from NLIW arrival times at successive moorings. This study concludes that velocity measurements taken from a single moored ADCP can provide useful estimates of vertical displacement, propagation direction, and propagation speed of large-amplitude NLIWs. © 2011 American Meteorological Society.

Lien R.-C.,University of Washington | D'Asaro E.A.,University of Washington | Henyey F.,University of Washington | Chang M.-H.,National Taiwan Ocean University | Tang T.-Y.,National Taiwan University
Journal of Physical Oceanography | Year: 2012

Large-amplitude (100-200 m) nonlinear internal waves (NLIWs) were observed on the continental slope in the northern South China Sea nearly diurnally during the spring tide. The evolution of one NLIW as it propagated up the continental slope is described. TheNLIW arrived at the slope as a nearly steady-state solitary depression wave. As it propagated up the slope, the wave propagation speedCdecreased dramatically from 2 to 1.3 m s -1, while the maximumalong-wave current speed U max remained constant at 2 m s -1. As U max exceeded C, the NLIW reached its breaking limit and formed a subsurface trapped core with closed streamlines in the coordinate frame of the propagating wave. The trapped core consisted of two counter-rotating vortices feeding a jet within the core. It was highly turbulent with 10-50-m density overturnings caused by the vortices acting on the background stratification, with an estimated turbulent kinetic energy dissipation rate of O(10 -4)W kg -1 and an eddy diffusivity of O(10 -1) m 2 s -1. The core mixed continually with the surrounding water and created a wake ofmixed water, observed as an isopycnal salinity anomaly.As the trapped core formed, theNLIWbecame unsteady and dissipative and broke into a large primarywave and a smallerwave.Although shoaling alone can lead towave fission, the authors hypothesize that the wave breaking and the trapped core evolution may further trigger the fission process. These processes of wave fission and dissipation continued so that the NLIW evolved from a single deep-water solitary wave as it approached the continental slope into a train of smaller waves on the Dongsha Plateau. Observed properties, including wave width, amplitude, and propagation speed, are reasonably predicted by a fully nonlinear steady-state internal wave model, with better agreement in the deeper water. The agreement of observed and modeled propagation speed is improved when a reasonable vertical profile of background current is included in the model. © 2012 American Meteorological Society.

Liu A.K.,Ocean University of China | Su F.-C.,National Museum of Marine Science and Technology | Hsu M.-K.,Taipei Chengshih University of Science and Technology | Kuo N.-J.,National Taiwan Ocean University | Ho C.-R.,National Taiwan Ocean University
Continental Shelf Research | Year: 2013

The objective of this study is to investigate the generation and evolution of mode-two internal waves on the shelf break. In this study, some historical mooring and satellite data have been investigated for the detection of mode-two solitons in the ocean. A recent field experiment in May 2009 near Dong-Sha Island in the South China Sea (SCS) is first described and analyzed. During the experiment, a small mode-two wave was observed following a huge mode-one soliton on the shelf. Then, the environmental conditions for the evolution of mode-two internal waves were assessed for parametric and sensitivity study based on the CTD data from previous experiment in SCS. The generation of mode-two waves on the shelf by disintegration of mode-one solitons in the deep ocean is proposed and analyzed based on the theory of modal-decomposition. For comparison, the soliton characteristics of mode-one and -two waves from environmental parameters have been estimated. It's been shown that the soliton width of large mode-two waves is much wider than mode-one waves. [U+25BA] We investigated the generation and evolution of mode-two solitons on the shelf break.[U+25BA] Historical mooring and satellite data have been investigated for the detection of mode-two solitons in the ocean.[U+25BA] The mode-two waves on the shelf are generated from the disintegration of mode-one solitons in the deep ocean.[U+25BA] The soliton width of large mode-two waves is much wider than mode-one waves. © 2013 Elsevier Ltd.

Huang H.-W.,National Taiwan Ocean University | Yeh Y.-M.,Nanhua University
Animal Conservation | Year: 2011

Seabird bycatch by the longline fisheries of the Pacific Ocean is a major conservation concern. However, relatively few studies have examined the impacts of distant water longline fishing on the high seas due to the difficulty associated with deploying observers. Our study addresses this data gap by analyzing data from 2666 Taiwanese scientific observation data sets from 2002 to 2007 to calculate the seabird bycatch rate and to estimate the mortality of seabirds as a result of fishing activities by the entire fleet. A total of 379 seabirds were caught and 88% were albatross. A negative binomial distribution was used to represent the observed data based on spatial and temporal stratification, which yielded bycatch rates that ranged from 0.0003 to 0.2213 birds per 1000 hooks. The bycatch rates were highest in the areas between 25-45°N and 165°E-160°W between October and March and the areas between 25-35°S and 170°E-165°W between April and September. Using the observed data for bycatch rates and total fishing effort, the estimated number of seabird deaths caused by the Taiwanese fleet ranged from 1120 to 4290 birds annually. Increasing the observer coverage of specific fleets and areas, prioritizing observer programs and combined with international cooperation in research, would improve bycatch calculations. Seabird conservation efforts can be improved by monitoring fishing effort and the mandatory implementation of multiple mitigation measures. © 2011 The Authors. Animal Conservation © 2011 The Zoological Society of London.

Lin J.-R.,National Taiwan Ocean University | Yan S.,National Central University | Lai C.W.,National Central University
Engineering Optimization | Year: 2013

The purpose of this study is to develop a planning model and a real-time adjustment model to help an international express company facing uncertain demands to plan courier routes and schedules and adjust the planned routes in actual operations. A solution procedure is then developed to efficiently solve the real-time adjustment model. A simulation-based evaluation method is also developed to compare the performance of the proposed models. The test results, related to an international express company's operations, show the good performance of the proposed models. Sensitivity analysis is also performed to gain better insights into knowing how several important parameters affect the solutions. © 2013 Copyright Taylor and Francis Group, LLC.

Wen C.-P.,National Chiao Tung University | Tuan P.-H.,National Chiao Tung University | Liang H.-C.,National Taiwan Ocean University | Huang K.-F.,National Chiao Tung University | Chen Y.-F.,National Chiao Tung University
IEEE Journal on Selected Topics in Quantum Electronics | Year: 2015

We report on a high-peak-power end-pumped AlGaInAs laser at 1.52 μm with a linear plane-parallel cavity. A high-reflective coated diamond is utilized not only as the heat spreader but also as the front mirror simultaneously to make the laser cavity to be extremely compact. The average output power and the corresponding peak power under this cavity configuration is found to be up to 2.58 and 516 W separately at a repetition rate of 100 kHz and a pump power of 12 W corresponding to a peak power of 2.4 kW. The experimental results assure the promising application of dielectric coated diamond as a multifunctional optics to fulfill a high performance and compact cavity design. © 1995-2012 IEEE.

Wang J.-C.,National Taiwan Ocean University | Li A.-T.,National Chiao Tung University | Tsai Y.-P.,National Chiao Tung University | Hsu R.-Q.,National Chiao Tung University
International Communications in Heat and Mass Transfer | Year: 2011

This paper aims to use the local heating mechanism, along with the excellent thermal performance of vapor chamber, to analyze and enhance the strength of products formed after insert molding process. In the insert molding process, the metal insert is firstly placed into the mold, and then formed into an embedded plastic product named diving regulator by injection molding. These results indicate that, the product formed by the local heating mechanism of vapor chamber can reduce the weld line efficiency and achieve high strength, which passed the standard of 15.82. N-m torque test, with a yield rate up to 100%. © 2010 Elsevier Ltd.

Liang Y.-C.,National Taiwan Ocean University | Lee H.-Y.,National Synchrotron Radiation Research Center | Lee H.-Y.,National Chiao Tung University
CrystEngComm | Year: 2010

Zr-doped In2O3 (Zr-In2O3) (222) epitaxial layers of thickness 210 nm were grown on yttria-stabilized zirconia (YSZ) (111) and Al2O3 (0001) substrates with rf magnetron sputtering at 350 °C in an atmosphere deficient in oxygen. X-Ray scattering and use of a transmission electron microscope (TEM) revealed Zr-In 2O3 films to be deposited epitaxially on YSZ (111) and Al2O3 (0001). Images observed with an atomic-force microscope demonstrate that the substrate profoundly affected the topography of the Zr-In2O3 (222) epilayers. The large mismatch of the Zr-In2O3 (222)/Al2O3 (0001) heteroepitaxy was responsible for the surface structure of the epilayer being rougher than that on YSZ (111). Cross-sectional TEM images reveal dense crystalline films with no macroscopic imperfection; the crystalline order of Zr-In2O3 epilayers is preserved up to the top surface. The Zr-In2O3 (222)/YSZ (111) heteroepitaxy has a Hall mobility greater than that of Zr-In2O3 (222)/Al 2O3 (0001), perhaps due to the greater lattice mismatch of the Zr-In2O3 (222)/Al2O3 (0001) heteroepitaxy that results in Zr-In2O3 having a poor crystalline quality. Domain boundaries on a nanometre scale were found in the heteroepitaxial Zr-In2O3 (222)/Al2O3 (0001) resulting from random nucleation and relaxation of misfit stress. The existence of these domain boundaries on a nanometre scale thus affects the electrical properties of the Zr-In2O3 epilayer. © 2010 The Royal Society of Chemistry.

Liang H.C.,National Taiwan Ocean University | Tsou C.H.,National Chiao Tung University | Lee Y.C.,National Chiao Tung University | Huang K.F.,National Chiao Tung University | Chen Y.F.,National Chiao Tung University
Laser Physics Letters | Year: 2014

The criterion for achieving the self-mode-locking (SML) in an optically pumped semiconductor laser (OPSL) with a linear cavity is systematically explored. Experimental results reveal that the occurrence of SML can be assisted by the existence of high-order transverse modes. Numerical analysis is performed to confirm that the critical pump power for obtaining the SML operation agrees very well with the pump threshold for exciting TEM1,0mode. The present finding offers an important insight into laser physics and a useful indication for obtaining the SML operation in OPSLs. © 2014 Astro Ltd.

Wang C.-M.,National Central University | Chang T.-Y.,National Taiwan Ocean University | Chiu C.-W.,National Taiwan Ocean University | Lin H.-M.,National Taiwan Ocean University | And 2 more authors.
Inorganic Chemistry | Year: 2014

Nanostructured zinc phosphite templated by cetyltrimethylammonium (CTA +) cations was synthesized using a hydro(solvo)thermal method. This is the first example of a crystalline metal phosphite containing long carbon tails of the CTA+ ions as templates in its structure, as is structurally characterized by single-crystal X-ray diffraction. The 2D inorganic structures with 4.82 topologies are constructed from the interconnection of tetrahedral ZnO3Br and HPO3 units, which are sandwiched between CTA+ ion surfactants in a packing behavior of a largely lamellar liquid-crystalline structure to extend the interlayer d spacing to 28.05 Å. Adsorption experiment shows selective adsorption properties of 1-naphthol and a adsorption capacity of 0.17 mmol/mmol (CTA)ZnBr(HPO3). This compound has potential as an adsorbent for the removal of 1-naphthol pollutant from wastewater. In addition, the naphthol-adsorbed sample shows interesting luminescent properties that are different from that of an as-synthesized sample. The crystal structure, thermal stability, IR spectrum, adsorption, and photoluminescence properties have been studied. © 2014 American Chemical Society.

Tsai Y.-P.,National Chiao Tung University | Wang J.-C.,National Taiwan Ocean University | Hsu R.-Q.,National Chiao Tung University
Experimental Techniques | Year: 2011

A heating and cooling system using a vapor chamber was developed and the effect of this chamber in an injection molding process on part tensile strength is studied. The upper and lower copper covers of the vapor chamber are made from C1100 oxygen-free copper, and the wick structure inside the chamber is composed of copper wire mesh with a uniform mesh spacer and copper walls of 50-μm diameter. The heating cycle is activated by a lever mechanism which pushes the vapor chamber into contact with the mold at the beginning of the filling stage. Five thermocouples are placed on the surface of cavity to measure the temperature of the vapor chamber. The temperature curves for 0-60 s with and without the vapor chamber show that the rapid uniform temperature increase employing a vapor chamber heating system is better even if the heater is in direct contact with point O on the surface of the cavity when no vapor chamber is used.

Juang J.-G.,National Taiwan Ocean University | Chien L.-H.,Qisda Corporation | Lin F.,TM Technology Inc.
IEEE Systems Journal | Year: 2011

This paper presents an adaptive neural network, designed to improve the performance of conventional automatic landing systems (ALS). Real-time learning was applied to train the neural network using the gradient-descent of an error function to adaptively update weights. Adaptive learning rates were obtained through the analysis of Lyapunov stability to guarantee the convergence of learning. In addition, we applied a DSP controller using the VisSim/TI C2000 Rapid Prototyper to develop an embedded control system and establish on-line real-time control. Simulations show that the proposed control scheme has superior performance to conventional ALS under conditions of wind disturbance of up to 75 ft/s. © 2010 IEEE.

Wang S.-H.,National Central University | Wang S.-H.,NASA | Hsu N.C.,NASA | Tsay S.-C.,NASA | And 5 more authors.
Geophysical Research Letters | Year: 2012

Satellite data estimate a high dust deposition flux (∼18 g m -2 a -1) into the northern South China Sea (SCS). However, observational evidence concerning any biological response to dust fertilization is sparse. In this study, we combined long-term aerosol and chlorophyll-a (Chl-a) measurements from satellite sensors (MODIS and SeaWiFS) with a 16-year record of dust events from surface PM 10 observations to investigate dust transport, flux, and the changes in Chl-a concentration over the northern SCS. Our result revealed that readily identifiable strong dust events over this region, although relatively rare (6 cases since 1994) and accounting for only a small proportion of the total dust deposition (∼0.28 g m -2 a -1), do occur and could significantly enhance phytoplankton blooms. Following such events, the Chl-a concentration increased up to 4-fold, and generally doubled the springtime background value (0.15 mg m -3). We suggest these heavy dust events contain readily bioavailable iron and enhance the phytoplankton growth in the oligotrophic northern SCS. Copyright 2012 by the American Geophysical Union.

News Article | November 10, 2016

STOCKHOLM, Sweden--(BUSINESS WIRE)--Leading ocean energy developer Minesto has today signed a collaboration agreement together with the Research Center for Ocean Energy and Strategies at National Taiwan Ocean University. The collaboration will include installation and ocean testing of a scale model and research on Minesto’s unique technology Deep Green. “This is a breakthrough on a market with substantial potential to Minesto”, says Dr Martin Edlund, CEO of Minesto. The collaboration agreement

Wei T.-Y.,National Taiwan Ocean University | Chang H.-Y.,National Taiwan Ocean University | Huang C.-C.,National Taiwan Ocean University | Huang C.-C.,Kaohsiung Medical University
RSC Advances | Year: 2013

In the present study, we develop a green approach for the preparation of tellurium nanotubes (Te NTs) by a simple fructose-mediated reduction of Te ions in an alkaline aqueous solution. The influence of reaction conditions, including the types of saccharides involved, reaction temperature, and fructose and NaOH concentrations on the size and morphology of Te nanostructures are investigated and the structural evolution with respect to different growth rates are illustrated. It is proposed that a low reduction reaction rate plays a significant role in the controlled growth mechanism of Te NTs. A simple gel-based membrane is also developed for the removal and sensing of mercury ions (Hg2+) in aqueous solutions. An agarose gel is used to trap as-prepared Te NTs, leading to the preparation of a nanocomposite film composed of Te NTs-modified agarose gel membrane (Te NTs-AGM) for removing Hg 2+ in the solution via the strong hybridization and galvanic replacement reaction of Te-Hg. The Te NTs-AGM adsorbent allows effective removal of mercury species spiked in tap, stream, and sea waters with efficiencies greater than 97%. In addition, Te NTs allow for the rapid and simple detection of Hg2+ at concentrations as low as 10 nM. We validate the practicality of the use of Te NTs-AGM in this application through analyses of Hg2+ in tap water, stream water, and sea water samples. The low-cost, effective, and stable Te NTs-AGM nanocomposite shows great potential for detection and economical removal of Hg2+. © 2013 The Royal Society of Chemistry.

Lien C.-W.,National Taiwan University | Tseng Y.-T.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University | Huang C.-C.,Kaohsiung Medical University | Chang H.-T.,National Taiwan University
Analytical Chemistry | Year: 2014

Functional logic gates based on lead ions (Pb2+) and mercury ions (Hg2+) that induce peroxidase-like activities in gold nanoparticles (Au NPs) in the presence of platinum (Pt4+) and bismuth ions (Bi3+) are presented. The "AND" logic gate is constructed using Pt4+/Pb2+ as the input and the peroxidase-like activity of the Au NPs as the output; this logic gate is denoted as "Pt4+/Pb2+(AND)-Au NPPOX". When Pt4+ and Pb2+ coexist, strong metallophilic interactions (between Pt and Pb atoms/ions) and aurophilic interactions (between Au and Pb/Pt atoms/ions) result in significant increases in the deposition of Pt and Pb atoms/ions onto the Au NPs, leading to enhanced peroxidase-like activity. The "INHIBIT" logic gate is fabricated by using Bi3+ and Hg2+ as the input and the peroxidase-like activity of the Au NPs as the output; this logic gate is denoted as "Bi3+/Hg 2+(INHIBIT)-Au NPPOX". High peroxidase-like activity of Au NPs in the presence of Bi3+ is a result of the various valence (oxidation) states of Bi3+ and Au (Au+/Au0) atoms on the nanoparticle's surface. When Bi3+ and Hg2+ coexist, strong Hg-Au amalgamation results in a large decrease in the peroxidase-like activity of the Au NPs. These two probes (Pt4+/ Pb2+(AND)-Au NPPOX and Bi3+/Hg 2+(INHIBIT)-Au NPPOX) allow selective detection of Pb 2+ and Hg2+ down to nanomolar quantities. The practicality of these two probes has been validated by analysis of Pb2+ and Hg2+ in environmental water samples (tap water, river water, and lake water). In addition, an integrated logic circuit based on the color change (formation of reddish resorufin product) and generation of O2 bubbles from these two probes has been constructed, allowing visual detection of Pb2+ and Hg2+ in aqueous solution. © 2014 American Chemical Society.

Liang Y.-C.,National Taiwan Ocean University | Tsai M.Y.,Chienkuo Technical University | Huang C.-L.,National Taiwan Ocean University | Hu C.-Y.,National Taiwan Ocean University | Hwang C.S.,Chienkuo Technical University
Journal of Alloys and Compounds | Year: 2011

ZnO thin films were grown on the 150 nm-thick RuO2-coated SiO2/Si substrates by electrochemical deposition in zinc nitrate aqueous solution with various electrolyte concentrations and deposition currents. Crystal orientation and surface structure of the electrodeposited ZnO thin films were characterized by X-ray diffraction (XRD) and scanning electron microscopy, respectively. The XRD results show the as-electrodeposited ZnO thin films on the RuO2/SiO2/Si substrates have mixed crystallographic orientations. The higher electrolyte concentration results in the ZnO thin films with a higher degree of c-axis orientation. Moreover, the use of an ultra-thin 5 nm-thick ZnO buffer layer on the RuO2/SiO 2/Si substrate markedly improves the degree of preferential c-axis orientation of the electrodeposited ZnO crystalline. The subsequent annealing in vacuum at a low temperature of 300 °C reduces the possible hydrate species in the electrodeposited films. The electrodeposited ZnO thin films on the 5 nm-thick ZnO buffered RuO2/SiO2/Si substrates grown in 0.02 M electrolyte at -1.5 mA with a subsequent annealing in vacuum at 300 °C had the best structural and optical properties. The UV to visible emission intensity ratio of the film can reach 7.62. © 2011 Elsevier B.V. All rights reserved.

Chang S.-W.,University of Illinois at Urbana - Champaign | Lin T.-R.,University of Illinois at Urbana - Champaign | Lin T.-R.,National Taiwan Ocean University | Chuang S.L.,University of Illinois at Urbana - Champaign
Optics Express | Year: 2010

Semiconductor plasmonic lasers at submicron and nanometer scales exhibit many characteristics distinct from those of their conventional counterparts at micron scales. The differences originate from their small sizes and the presence of metal plasma surrounding the cavity. To design a laser of this type, features such as metal dispersion, optical energy confinement, and group velocity have to be taken into account properly. In this paper, we provide a comprehensive approach to the design and performance evaluation of plasmonic Fabry-Perot nanolasers. In particular, we show the proper procedure to obtain the key parameters, especially the quality factor and threshold gain, which are usually neglected in conventional semiconductor Fabry-Perot lasers but become important for nanolasers. © 2010 Optical Society of America.

Huang R.-C.,National Taiwan Ocean University | Chiu W.-J.,National Taiwan Ocean University | Li Y.-J.,National Taiwan Ocean University | Huang C.-C.,National Taiwan Ocean University | Huang C.-C.,Kaohsiung Medical University
ACS Applied Materials and Interfaces | Year: 2014

In this study, we developed a label-free, ultrasensitive graphene oxide (GO)-based probe for the detection of oligonucleotides by laser desorption/ionization mass spectrometry (LDI-MS). On the basis of simple π-π stacking and electrostatic interactions between rhodamine 6G (R6G) and GO, we prepared the nanocomposite R6G-modified GO (R6G-GO). Signal intensities of R6G increased in mass spectra in the presence of single-stranded oligonucleotides under pulsed laser irradiation (355 nm) of R6G-GO. In addition, the signal intensity of R6G was stronger in the presence of short oligonucleotides. Because small oligonucleotides improve the LDI efficiency of R6G on GO, we designed an enzyme-amplified signal transduction probe system for the detection of microRNA (miRNA). After specific digestion of the probe DNA (pDNA) strand from pDNA/miRNA-hybridized complexes by exonuclease III (Exo III), the resulting small oligonucleotide fragments increased the R6G signal during LDI-MS of R6G-GO. In addition, the signal intensity of the R6G ions increased with increasing concentrations of the target miRNA. Coupling this enzyme reaction and R6G-GO with LDI-MS enabled the detection of miRNA at concentrations of the femtomolar (fM) level. We also demonstrated the analysis of miRNA in tumor cells and utilized this R6G-GO probe in the detection of a single-nucleotide polymorphism (SNP) in the Arg249Ser unit of the TP53 gene. This simple, rapid, and sensitive detection system based on the coupling of functional GO with LDI-MS appears to have great potential as a tool for the bioanalyses of oligonucleotides and proteins. © 2014 American Chemical Society.

Lu H.-A.,National Taiwan Ocean University | Chu C.-W.,National Taiwan Ocean University | Che P.-Y.,Kuehne Nagel Ltd.
Journal of Marine Science and Technology | Year: 2010

This research addresses a slot allocation planning problem of the container shipping company for satisfying the estimated seasonal demands on a liner service. We explore in detail the influenced factors of planning and construct a quantitative model for the optimum allocation of the ship's slot spaces. An integer programming model is formulated to maximize the potential profits per round trip voyage for a liner company, and a real life example of an eastern Asia short sea service has been studied. Analysis results reveal that containers with the higher contributions like reefers and 40 feet dry containers have priorities to be allocated more than others, but not all because of satisfying necessary operational constraints. Our model is not only providing a higher space utilization rate and more detailed allocation results, but also helpful for the ship size assessment in long-term planning.

Lai H.-T.,National Chiayi University | Lin J.-S.,National Chiayi University | Chien Y.-H.,National Taiwan Ocean University
Bioresource Technology | Year: 2011

This study investigated the effects of light (visible light - 5800lux, 24h) or dark regime and aerobic or anaerobic condition on the decay of added oxolinic acid (OA) at 5, 10 and 20mgL -1 in eel pond sediment. An asymptotic decaying exponential model C t=C min+C o×exp (-k×t) was used to facilitate quantitative approach to OA transformation, where C t is the concentration of OA after t days, C min the estimated level-off concentration of OA residue, C o the concentration of added OA and k the decaying coefficient. OA decayed faster under light (C min=4.6mgL -1) than under dark (C min=7.8mgL -1) and also decayed faster under aerobic (C min=4.0mgL -1) than under anaerobic condition (C min=8.5mgL -1). C min increased with C o. Sundrying and tilling eel pond bottom should be able to reduce OA residue significantly. © 2010 Elsevier Ltd.

Lee D.-H.,National Taiwan Ocean University | Lee D.-J.,National Taiwan University of Science and Technology | Lee D.-J.,Fudan University | Veziroglu A.,International Association for Hydrogen Energy
Bioresource Technology | Year: 2011

Biohydrogen is considered as an attractive clean energy source due to its high energy content and environmental-friendly conversion. Analyzing various economic scenarios can help decision makers to optimize development strategies for the biohydrogen sector. This study surveys econometric models of biohydrogen development, including input-out models, life-cycle assessment approach, computable general equilibrium models, linear programming models and impact pathway approach. Fundamentals of each model were briefly reviewed to highlight their advantages and disadvantages. The input-output model and the simplified economic input-output life-cycle assessment model proved most suitable for economic analysis of biohydrogen energy development. A sample analysis using input-output model for forecasting biohydrogen development in the United States is given. © 2011 Elsevier Ltd.

Kuo M.-S.,Kainan University | Kuo M.-S.,National formosa University | Liang G.-S.,National Taiwan Ocean University
Expert Systems with Applications | Year: 2011

The aim of this paper was to present an effective approach for evaluating service quality of Northeast-Asian international airports by conducting customer surveys. In general, evaluation of service quality is a complex multicriteria decision-making (MCDM) problem; therefore, a complex decision process is often involved in which multiple requirements and fuzzy conditions have to be taken into consideration simultaneously. By combining concepts of VIKOR and grey relational analysis (GRA), a new fuzzy MCDM method was proposed to deal with the evaluation of service quality problems in the international airports. This model was solved by an effective algorithm, which incorporated the decision-maker's attitude and/or preference for customers' assessments on weights and performance ratings of each criterion. An empirical study for evaluating service quality of seven major Northeast-Asian international airports was put forth to illustrate an application of the proposed model. The study results showed that this approach is an effective means for tackling MCDM problems involving subjective assessments of qualitative attributes in a fuzzy environment. © 2010 Elsevier Ltd. All rights reserved.

Kuo M.-S.,Kainan University | Kuo M.-S.,National formosa University | Liang G.-S.,National Taiwan Ocean University
Mathematical and Computer Modelling | Year: 2011

The criteria in multiple criteria decision-making (MCDM) problems often have independent and dependent characteristics simultaneously, so they cannot be evaluated by conventional additive or non-additive measures in real-life environments. This paper proposes a new hybrid MCDM model to solve location selection problems, and the results of solving MCDM problems tallied with real-life circumstances due to the use of two concepts in the new hybrid model. The concepts comprise a new structural model and a new evaluation method. The new structural modeling technique is used to draw the hierarchical/network framework, and the MCDM problem is solved using the proposed evaluation method. Here, the fuzzy ANP (analytic network process) is used to construct fuzzy weights of all criteria. Linguistic terms characterized by triangular fuzzy numbers are then used to denote the evaluation values of all alternatives versus various criteria. Finally, the aggregation fuzzy assessments of different alternatives are ranked to determine the best selection. Furthermore, this paper uses a numerical example for selecting the location of an international distribution center in Pacific Asia to illustrate the proposed method. Through this example, this paper demonstrates the applicability of the proposed method, and the results show that this method is an effective means for tackling MCDM problems. © 2011 Elsevier Ltd.

Chen C.-L.,National Taiwan Ocean University | Chen Z.-Y.,National Taiwan Ocean University | Lee T.-Y.,Minghsin University of Science and Technology
International Journal of Electrical Power and Energy Systems | Year: 2014

Wind power penetration in Taiwan power system faces significant barriers due to limited transmission capability. One of the most important future challenges seems to be the management of the integration of fluctuations in the electricity production from wind energy sources. The problem is further complicated by the generation dispatch imposed by the presence of transmission capacity limits. Several new important concepts about economic dispatch (ED) model are investigated in this paper for the large-scale wind capacity integration. A penalty function-hybrid direct search method (PF-HDSM) is also developed for the solution of multi-area wind-thermal coordination dispatch (MWCD) problem. Several important issues of wind capacity integration in the Taiwan power system are discussed by using the developed MWCD software. Numerical experiments are included to illustrate the impacts of transmission capacity limits on wind power penetration level in each area and to assess the impact and economic benefits of the installation of wind farms for the Taiwan power system. © 2013 Published by Elsevier Ltd.

Weng S.-S.,National Chiayi University | Liu S.-M.,National Taiwan Ocean University | Lai H.-T.,National Chiayi University
Bioresource Technology | Year: 2013

This is the first study to examine the application parameters for oxidation of two sulfonamide antibiotics (SAs), sulfadimethoxine (SDM) and sulfamonomethoxine (SMM), using a novel laccase and mediators. The optimal conditions in the laccase-mediator system (LMS) were pH 4, 50-60. °C, and 1. mM for 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS); pH 4, 40-60. °C, and 1. mM for violuric acid (VLA); pH 6, 50. °C, and 2. mM for syringaldehyde (SIR). Additionally, the conditions of the 4-hydroxybenzyl alcohol (HBA) mediator were pH 4, 30. °C, and 2. mM in the oxidation of SDM; and the temperature increased to 60. °C for SMM. The laccase coupled with VLA and HBA resulted in the lowest toxicity of the SA solutions during processing, whereas treatments with ABTS and SIR resulted in higher toxicities. Furthermore, the laccase used in this study was stable and resistant to dialysis, thus can be reused for oxidation process. © 2013 Elsevier Ltd.

Lin Y.-H.,National Pingtung University of Science and Technology | Ku C.-Y.,National Taiwan Ocean University | Shiau S.-Y.,National Taiwan Ocean University | Shiau S.-Y.,Providence University | Shiau S.-Y.,Fu Jen Catholic University
Aquaculture | Year: 2013

A growth trial was conducted to quantify the dietary magnesium (Mg) requirement for hybrid tilapia, Oreochromis niloticus×Oreochromis aureus, reared in freshwater and seawater. A semi-purified basal diet was supplemented with eight levels of magnesium sulfate (0.025, 0.061, 0.082, 0.15, 0.23, 0.30, 0.36 and 0.57gMgkg-1 diet), each was fed to triplicate groups of tilapia (initial body weight: 0.88±0.01g) reared either in the freshwater or seawater for 8weeks. The Mg concentration in freshwater and seawater was approximately 4 and 1,400mgMg L-1, respectively. Tilapia reared in freshwater, weight gain (WG) was highest (P<0.05) in fish fed diets supplemented with ≥0.15gMg kg-1 diet, followed by fish fed the diet with 0.061gMg kg-1 diet, and lowest in fish fed the diet with 0.025gMg kg-1 diet. Plasma alkaline phosphatase (ALP) activity was higher in fish fed diets with 0.23 and 0.30gMg kg-1 diet than that in fish fed the unsupplemented diet. The concentration of Mg in whole body, scale, muscle and plasma increased when dietary Mg concentration increase from 0.025 to 0.23gMg kg-1 diet and then stabilized after further increase in dietary Mg. In the seawater reared group, WG, plasma ALP activity, whole body, scale, muscle and plasma Mg concentration of tilapia were similar (P>0.05) among all dietary treatments. Analysis of WG, ALP activity, whole body, scale, muscle and plasma Mg concentration by broken-line model and whole body Mg retention by linear regression of the fish indicated the optimum dietary Mg requirement for tilapia reared in freshwater is about 0.2gMg kg-1 diet. The result also suggests that dietary Mg beyond 0.025gMg kg-1 is required for tilapia reared in seawater. © 2012 Elsevier B.V.

Shen Y.-W.,National Taiwan Ocean University | Hsu P.-H.,National Taiwan Ocean University | Unnikrishnan B.,National Taiwan Ocean University | Li Y.-J.,National Taiwan Ocean University | And 2 more authors.
ACS Applied Materials and Interfaces | Year: 2014

We report a label-free colorimetric strategy for the highly selective and sensitive detection of iodide (I-) ions in human urine sample, seawater and edible salt. A poly(N-vinyl-2-pyrrolidone)-stabilized Au nanoparticle (34.2-nm) was prepared to detect I- ions using silver (Ag+) and cyanide (CN-) ions as leaching agents in a glycine-NaOH (pH 9.0) solution. For the visual detection of the I- ions by naked eye, and for long time stability of the probe, Au nanoparticles (NPs) decorated mixed cellulose ester membrane (MCEM) was prepared (Au NPs/MCEM). The Au NPs-based probe (CN-/Ag+-Au NPs/MCEM) operates on the principle that Ag+ ions form a monolyar silver atoms/ions by aurophilic/argentophilic interactions on the Au NPs and it accelerates the leaching rate of Au atoms in presence of CN- ions. However, when I- is introduced into this system, it inhibits the leaching of Au atoms because of the strong interactions between Ag/Au ions and I- ions. Inductively coupled plasma mass spectrometry, surface-assisted laser desorption/ionization time-of-flight mass spectrometry were used to characterize the surface properties of the Au NPs in the presence of Ag+ and I-. Under optimal solution conditions, the CN-/Ag+-Au NPs/MCEM probe enabled the detection of I - by the naked eye at nanomolar concentrations with high selectivity (at least 1000-fold over other anions). In addition, this cost-effective probe allowed the determination of I- ions in complex samples, such as urine, seawater, and edible salt samples. © 2014 American Chemical Society.

Jen Y.-M.,National Taiwan Ocean University | Lin H.-B.,Chung Hua University
Materials and Design | Year: 2013

The monotonic and fatigue strengths of adhesively bonded aluminum honeycomb sandwich beams subjected to four-point bending were investigated at temperatures ranging from -25 to 75 °C. Experimental results showed that the ultimate loads in the monotonic tests and fatigue strengths in the fatigue tests decrease as temperature increases, and the failure mode changes from local indentation to debonding at the skin/core interfaces. An analytical procedure based on the temperature-dependent monotonic strengths of face/core materials and simple adhesively bonded specimens were used and accurately predicted the ultimate applied loads in the monotonic tests by comparing the theoretical limit loads corresponding to several failure modes, i.e., face failure, local indentation, core shear failure, and face/core debonding modes. Furthermore, by modifying the monotonic analytical procedure and incorporating the temperature-dependent S-N curves of the face/core materials and the simple adhesively bonded specimens, the fatigue life of the sandwich beams could be predicted by comparing the estimated fatigue lives corresponding to various failure modes. Comparing the evaluated ultimate loads and fatigue lives with the observed data confirmed that the good prediction performance was obtained both in the monotonic and fatigue analyses. © 2012 Elsevier Ltd.

Jen Y.-M.,National Taiwan Ocean University | Huang C.-Y.,Chung Hua University
Journal of Composite Materials | Year: 2013

This study investigates how the acid treatment of multi-walled carbon nanotubes affects the fatigue behavior of carbon nanotube/epoxy composites. Nanocomposites with 0.5 and 1.0 wt% acid-treated carbon nanotubes display slightly and significantly stronger fatigue strength than those with equal-content as-received carbon nanotubes, respectively. However, excessive addition of carbon nanotubes fails to increase the fatigue resistance of epoxy resins, owing to carbon nanotube agglomeration. Furthermore, the fatigue strength of nanocomposites depend on the ultimate strength rather than the carbon nanotube contents or treatments. Furthermore, how carbon nanotube contents and related treatments influence the fatigue strength of the nanocomposites is elucidated by examining the fractographs of the specimens. © The Author(s) 2012.

Simmons H.,University of Alaska Fairbanks | Chang M.-H.,National Taiwan Ocean University | Chang Y.-T.,National Taiwan University | Chao S.-Y.,University of Cambridge | And 3 more authors.
Oceanography | Year: 2011

Nonlinear internal solitary waves generated within Luzon Strait move westward across the northern South China Sea, refract around Dongsha Atoll, and dissipate on the Chinese continental shelf after a journey of over 500 km lasting more than four days. In the last 10 years a great deal of observational, theoretical, and modeling effort has been directed toward understanding and predicting these solitary waves and their effects on the oceanography of the northern South China Sea. This paper reviews a variety of modeling approaches (two- and three-dimensional, kinematic, hydrostatic, and nonhydrostatic) that have been employed to gain insight into the generation mechanisms and physics of the South China Sea's nonlinear solitary waves with the goal of predicting wave characteristics such as phase speed, amplitude, and arrival time.

Lin S.-G.,National Taiwan Ocean University | Yu F.-C.,Minghsin University of Science and Technology
Survey Review | Year: 2013

Conventionally, cycle slips are detected by combining phase observations or phase/code observations. However, this is unsuitable for single frequency receivers in real time kinematic (RTK) positioning. Therefore, this study introduces an algorithm based on outlier detection concept to the detection and repair of cycle slip during GPS RTK positioning. The efficacy of the algorithm was verified on a low cost single frequency GPS receiver. To investigate the ability of the algorithm to detect error within a single cycle, minimum detectable bias (MDB) of less than one cycle was used as the index of success. Experiments verified the availability of the algorithm up to 96?12% (10u mask angle). The algorithm was able to accurately detect the time when cycle slips occur and precisely estimate their size in various simulated scenarios. Finally, tests were performed based on real data, and the results confirm that the proposed algorithm is applicable for single frequency RTK positioning. © 2013 Survey Review Ltd.

Li Y.-J.,National Taiwan Ocean University | Tseng Y.-T.,National Taiwan Ocean University | Unnikrishnan B.,National Taiwan Ocean University | Huang C.-C.,National Taiwan Ocean University | Huang C.-C.,Kaohsiung Medical University
ACS Applied Materials and Interfaces | Year: 2013

We report an efficient method for the determination of iodide (I -) ions by using gold-iodide hybrid cluster ions on gold nanoparticles (Au NPs) modified mixed cellulose ester membrane (Au NPs-MCEM) by pulsed laser desorption/ionization mass spectrometry (LDI-MS). When I - ions were deposited and concentrated on the surfaces of Au NPs (32 nm) via strong Au+-I- interaction on the MECM, the Au NPs-MCEM was observed to function as an efficient surface-assisted LDI substrate with very low background noise. When pulsed laser radiation (355 nm) was applied, I- binding to Au NPs ions induced the enhancement of the desorption and ionization efficiency of gold-iodide hybrid cluster ions from the Au NPs surfaces. The reproducibility of the probe for both shot-to-shot and sample-to-sample (both less than 10%) ion production was also improved by the homogeneous nature of the substrate surface. Thus, it allows the accurate and precise quantification of I- ions in high-salinity real samples (i.e., edible salt samples and urine) at the nanomolar range. This novel LDI-MS approach provides a simple route for the high-speed analysis of I- ions with high sensitivity and selectivity in real biological samples. © 2013 American Chemical Society.

Lien C.-W.,National Taiwan University | Chen Y.-C.,National Taiwan University | Chang H.-T.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University | Huang C.-C.,Kaohsiung Medical University
Nanoscale | Year: 2013

In this study we employed self-deposition and competitive or synergistic interactions between metal ions and gold nanoparticles (Au NPs) to develop OR, AND, INHIBIT, and XOR logic gates through regulation of the enzyme-like activity of Au NPs. In the presence of various metal ions (Ag+, Bi 3+, Pb2+, Pt4+, and Hg2+), we found that Au NPs (13 nm) exhibited peroxidase-, oxidase-, or catalase-like activity. After Ag+, Bi3+, or Pb2+ ions had been deposited on the Au NPs, the particles displayed strong peroxidase-like activity; on the other hand, they exhibited strong oxidase- and catalase-like activities after reactions with Ag+/Hg2+ and Hg 2+/Bi3+ ions, respectively. The catalytic activities of these Au NPs arose mainly from the various oxidation states of the surface metal atoms/ions. Taking advantage of this behavior, we constructed multiplex logic operations - OR, AND, INHIBIT, and XOR logic gates - through regulation of the enzyme-like activity after the introduction of metal ions into the Au NP solution. When we deposited Hg2+ and/or Bi3+ ions onto the Au NPs, the catalase-like activities of the Au NPs were strongly enhanced (>100-fold). Therefore, we could construct an OR logic gate by using Hg 2+/Bi3+ as inputs and the catalase-like activity of the Au NPs as the output. Likewise, we constructed an AND logic gate by using Pt 4+ and Hg2+ as inputs and the oxidase-like activity of the Au NPs as the output; the co-deposition of Pt and Hg atoms/ions on the Au NPs was responsible for this oxidase-like activity. Competition between Pb 2+ and Hg2+ ions for the Au NPs allowed us to develop an INHIBIT logic gate - using Pb2+ and Hg2+ as inputs and the peroxidase-like activity of the Au NPs as the output. Finally, regulation of the peroxidase-like activity of the Au NPs through the two inputs Ag+ and Bi3+ enabled us to construct an XOR logic gate. © 2013 The Royal Society of Chemistry.

Chang C.-W.,National Center for High Performance Computing | Liu C.-S.,National Taiwan University | Chang J.-R.,National Taiwan Ocean University
Computers, Materials and Continua | Year: 2010

In this article, we propose a semi-analytical method to tackle the twodimensional backward heat conduction problem (BHCP) by using a quasi-boundary idea. First, the Fourier series expansion technique is employed to calculate the temperature field u(x,y,t) at any time t < T. Second, we consider a direct regularization by adding an extra term αu(x, y, 0) to reach a second-kind Fredholm integral equation for u(x; y, 0): The termwise separable property of the kernel function permits us to obtain a closed-form regularized solution. Besides, a strategy to choose the regularization parameter is suggested. When several numerical examples were tested, we find that the proposed scheme is robust and applicable to the two-dimensional BHCP. © 2010 Tech Science Press.

Liu Y.-C.,National Taiwan Ocean University | Li Y.-J.,National Taiwan Ocean University | Huang C.-C.,National Taiwan Ocean University | Huang C.-C.,Kaohsiung Medical University
Analytical Chemistry | Year: 2013

In this study, we employed laser desorption/ionization mass spectrometry (LDI-MS) to explore the interactions between thiolated DNA (HS-DNA) and gold nanoparticles (Au NPs). Under nanosecond-pulsed laser irradiation (Nd:YAG, 355 nm), the efficiency of Au cluster ion formation from the Au NPs decreased in the presence of HS-DNA. At the optimal laser power density (2.1 × 10 4 W cm-2), the intensity of the Au cluster signal was sensitive to the DNA coverage and the length of the DNA strands on the Au NPs (diameter: 13 nm). Using this information, we developed a simple and specific DNA sensor that operates through analysis of the Au cluster ions formed from the fragmentation of Au NPs under LDI conditions. The coverage of the thiolated probe DNA (pDNA) on the Au NPs increased in the presence of its perfectly matched DNA (DNApm). As a result, the intensity of the signal of Au cluster ions decreased upon increasing the concentration of DNApm. Coupling these pDNA-Au NPs with LDI-MS allowed the detection of DNApm at concentrations down to the nanomolar regime. Furthermore, we applied this pDNA-Au NP probe to the detection of single-nucleotide polymorphisms (SNPs) of the Arg249Ser unit in the TP53 gene. To the best of our knowledge, this paper provides the first example of the use of LDI to analyze the coverage and structure of DNA strands on metal NPs. This simple, rapid, high-throughput detection system, based on the coupling of biofunctional Au NPs with LDI-MS, appears to hold great practicality for bioanalyses of oligonucleotides and proteins. © 2012 American Chemical Society.

Chen W.-Y.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University | Huang C.-C.,Kaohsiung Medical University | Chen L.-Y.,National Taiwan University | Chang H.-T.,National Taiwan University
Nanoscale | Year: 2014

Highly photoluminescent gold nanodots (Au NDs) via etching and co-deposition of hybridized ligands [11-mercaptoundecanol (11-MU) and its complexes with amphiphilic ligands] on gold nanoparticles (∼3 nm) have been prepared and employed for the detection of nitrite based on the analyte-induced photoluminescence quenching. This journal is © the Partner Organisations 2014.

Chiou Y.-C.,National Chiayi University | Jen Y.-M.,National Taiwan Ocean University | Huang S.-H.,Chung Hua University
Microelectronics Reliability | Year: 2011

This paper develops an analysis procedure to study the effects of intermetallic compound (IMC) growth on the fatigue life of 63Sn-37Pb (lead-rich)/96.5Sn-3.5Ag (lead-free) solder balls for flip-chip plastic ball grid array packages under thermal cycling test conditions. In this analysis procedure, the thickness of the IMC increased with the number of thermal cycles, and was determined using the growth rate equation. A series of non-linear finite element analyses was conducted to simulate the stress/strain history at the critical locations of the solder balls with various IMC thicknesses in thermal cycling tests. The simulated stress/strain results were then employed in a fatigue life prediction model to determine the relationship between the predicted fatigue life of the solder ball and the IMC thickness. Based on the concept of continuous damage accumulation and incorporated with the linear damage rule, this study defines the damage of each thermal cycle as the reciprocal of the predicted fatigue life of the solder joints with the corresponding IMC thickness. The final fatigue failure of the solder ball was determined as the number of cycles corresponding to the cumulative damage equal to unity. Results show that the solder joint fatigue life decreased as the IMC thickness increased. Moreover, the predicted thermal fatigue life of lead-rich solders based on the effects of IMC growth is apparently smaller than that without considering the IMC growth in the reliability analysis. Results also show that the influence of the IMC thickness on the fatigue life prediction of the lead-free solder joint can be ignored. © 2011 Elsevier Ltd. All rights reserved.

Jen Y.-M.,National Taiwan Ocean University | Teng F.-L.,Chung Hua University | Teng T.-C.,Chung Hua University
Materials and Design | Year: 2014

This study experimentally investigates two-stage cumulative bending fatigue behavior of adhesively bonded aluminum sandwich panels with local indentation failure mode. Experimental results show that the sums of cycle ratios of both stages are larger and less than unity when their loading sequence is low-to-high and high-to-low, respectively. The Miner's rule fails to predict the loading sequence effect observed in cumulative fatigue tests. The variations in stiffness and residual strength of the studied specimens with the applied cycles in the constant-amplitude fatigue tests were also observed and recorded. Furthermore, the non-linear damage rule, which is based on the stiffness degradation of the specimens, provides better prediction of the remaining fatigue lives in the second stage than the traditional linear damage rule. However, the residual strength remains almost constant until the final stage of the constant-amplitude fatigue tests, demonstrating that residual strength is not a suitable indicator of non-linear damage in predicting the cumulative fatigue lives. © 2013 Elsevier Ltd.

Jen Y.-M.,National Taiwan Ocean University | Huang C.-Y.,Chung Hua University
Transactions of the Canadian Society for Mechanical Engineering | Year: 2013

This study experimentally analyzed the hygrothermal effect on the static and fatigue strengths of multi-walled carbon nanotubes (CNTs)/epoxy composites. The results show that the static and fatigue strengths decreased slightly at 25°C/85% RH environments compared with those tested under the 25°C/60% RH condition. However, the strengths decreased substantially under the 40°C/85% RH condition, indicating that the combined temperature and humidity environments weaken the interfacial adhesion between the CNT surfaces and the epoxy matrix.

Tsai S.-F.,University of Connecticut | Tsai S.-F.,National Taiwan Ocean University | Chen W.-T.,National Taiwan Ocean University | Chiang K.-P.,National Taiwan Ocean University
Journal of Eukaryotic Microbiology | Year: 2015

We redescribe Cyrtostrombidium longisomum Lynn & Gilron, 1993, the type species of the genus Cyrtostrombidium, and describe the new species Cyrtostrombidium paralongisomum n. sp. using live observation, protargol staining and molecular data. The morphological characters of these two species are clearly distinct, i.e., dikinetid numbers in the girdle and ventral kineties; however, it is difficult to separate them by 18S rDNA sequences because they differ by only 8 bp, indicating that 18S rDNA sequences are insufficient for separating different species in the genus Cyrtostrombidium. We not only observed the position of the oral primordium in the genus Cyrtostrombidium but also observed a possibly homoplasious trait, a dorsal split in the girdle kinety, in (1) Apostrombidium, (2) Varistrombidium, and (3) Cyrtostrombidium/Williophrya. This partially supports the hypothesis of somatic ciliary pattern evolution recently put forth by Agatha and Strüder-Kypke. © 2014 The Author(s) Journal of Eukaryotic Microbiology © 2014 International Society of Protistologists.

Yan J.-T.,Chung Hua University | Tseng Y.-J.,Chung Hua University | Yen C.-H.,National Taiwan Ocean University
Proceedings - IEEE International Symposium on Circuits and Systems | Year: 2014

It is well known that single-layer routing is used for RDL routing in flip-chip designs and substrate routing in package designs. In this paper, given a set of two-terminal nets in a single-layer gridded routing plane, the routing regions of all the given nets can be initially constructed. Based on the routing constraints on different intersection conditions of two routing regions in a single layer, the wiring directions of the given nets can be further assigned. Finally, based on the assigned directions of the given nets, the wiring paths of the given nets onto the routing grids can be assigned by diffusing the overlapping paths and eliminating the unnecessary detours in single-layer routing. The experimental results show that our proposed approach can route 99.98% of the given nets in single-layer routing for 6 tested examples in reasonable CPU time on the average. © 2014 IEEE.

Chang Y.-C.,National Taiwan Ocean University | Yu M.-M.,National Taiwan Ocean University | Chen P.-C.,Chung Hua University
Journal of Air Transport Management | Year: 2013

This paper assesses whether geographical characteristics and service strategies influence the performance of Chinese airports. It examines the technical efficiency of 41 Chinese airports in 2008; with data envelopment analysis then regressed on environmental factors. The results show that airports located in cities with populations of more than two million are more efficient than those for other city sizes. Further, airports that are able to accommodate A380 or Boeing 747 aircraft are operationally more efficient than other categories, and airports' efficiency improves with the number of airlines using them. The distance between an airport and the local central business district, however, does not significantly affect its performance. © 2012 Elsevier Ltd.

Kuo M.-S.,Kainan University | Kuo M.-S.,National formosa University | Liang G.-S.,National Taiwan Ocean University
Applied Soft Computing Journal | Year: 2012

This study presented a new performance evaluation method for tackling fuzzy multicriteria decision-making (MCDM) problems based on combining VIKOR and interval-valued fuzzy sets. The performance evaluation problem often exists in complex administrative processes in which multiple evaluation criteria, subjective/objective assessments and fuzzy conditions have to be taken into consideration simultaneously in management. Here, the subjective, imprecise, inexact and uncertain evaluation processes are modeled as fuzzy numbers by means of linguistic terms, as fuzzy theory can provide an appropriate tool to deal with such uncertainties. However, the presentation of linguistic expressions in the form of ordinary fuzzy sets is not clear enough [15,21]. Interval-valued fuzzy sets can provide more flexibility [4,14] to represent the imprecise/vague information that results, and it can also provide a more accurate modeling. This paper presents the interval-valued fuzzy VIKOR, which aims to solve MCDM problems in which the weights and performances of criteria are unequal by using the concepts of interval-valued fuzzy sets. A case study for evaluating the performances of three major intercity bus companies from an intercity public transport system is conducted to illustrate the effectiveness of the method. © 2011 Elsevier B.V. All rights reserved.

Jen Y.-M.,National Taiwan Ocean University | Wang Y.-C.,Chung Hua University
Composites Part B: Engineering | Year: 2012

This study experimentally investigates the stress concentration effect on the fatigue properties of multi-walled nanotube (MWCNT)/epoxy nanocomposites by employing the dumbbell type specimens with central through-hole notches. Both the hole sizes and the CNT contents are considered as the experimental variables. The experimental results show that the fatigue strengths of the notched nanocomposites decrease with an increase in hole sizes. The notch sensitivity factors increase with the notch root radii and the ultimate strengths of the nanocomposite specimens. This study employed a mathematical model to relate the notch sensitivity with the hole size and a material constant, and this employed material constant was found to depend on the ultimate strength rather than the CNT contents of the nanocomposites. © 2012 Elsevier Ltd. All rights reserved.

Chung L.-Y.,National Yang Ming University | Chung L.-Y.,Taipei Medical University Hospital | Tang S.-J.,National Taiwan Ocean University | Wu Y.-C.,National Yang Ming University | And 5 more authors.
Oncotarget | Year: 2015

Cancer stem cells (CSCs) are comprised of a rare sub-population of cells in tumors that have been proposed to be responsible for high recurrence rates and resistance to chemotherapy. Galectins are highly expressed in cancers that correlate with the aggressiveness of tumors. Galectins may also promote the resistance of cancer cells to chemotherapy. However, the role of galectins in CSCs remains unknown. In this study, sphere formation was used to enrich H1299 human lung CSCs that had self-renewal ability, advanced tumorigenic potential, and that highly expressed stem/progenitor cell markers such as Oct4, Sox2, Nanog, and CD133. A novel candidate molecule, galectin-3, for stemness was found in lung CSCs. The expression of galectin-3 robustly increased in lung cancer spheres over serial passages, but its suppression in the H1299 monolayer or spheres resulted in reduced expression of stemness-related genes, sphere-forming ability, tumorigenicity, chemoresistance, and tumor initiation in mice. Notably, the overexpression of galectin-3 in A549 lung cancer cells, which have low capability to grow as tumor spheres, promoted CSC formation. β-catenin activity was increased in H1299 spheres and counteracted by galectin-3 suppression. Thus, galectin-3 may act as a cofactor by interacting with β-catenin to augment the transcriptional activities of stemness-related genes. Furthermore, galectin-3 expression correlated with tumor progression and expressions of β-catenin and CSC marker CD133 in lung cancer tissues. Targeting galectin-3 signaling may provide a new strategy for lung cancer treatment by inhibiting stem-like properties.

Chiu W.-C.,National Taiwan Ocean University | Huang C.-C.,National Taiwan Ocean University | Huang C.-C.,Kaohsiung Medical University
Analytical Chemistry | Year: 2013

In this paper, we describe a pulsed-laser desorption/ionization mass spectrometry (LDI-MS) approach for the detection of plasmin with subnanomolar sensitivity through the analysis of gold (Au) clusters desorbed from fibrinogen-modified gold nanoparticles (Fib-Au NPs) on a mixed cellulose ester membrane (MCEM). The mechanism of action of this probe is based on the plasmin-mediated cleavage of the Fib-Au NPs and the reduced interaction between Fib-Au NPs and MCEM. The Fib-Au NPs were deposited onto the MCEM to form a highly efficient background-free surface-assisted LDI substrate. Under pulsed laser irradiation (355 nm), the cleaved Fib-Au NPs decreased the adsorbed on MCEM. As a result, the intensities of the signals of the Au clusters decreased in the mass spectra. This approach provided a highly amplified target-labeling indicator for the analysis of plasmin. Under optimized conditions, this probe was highly sensitive (limit of detection: ca. 0.1 nM) and selective (by at least 1000-fold over other enzymes and proteins) toward plasmin; it also improved the reproducibility (<5%) of ion production by presenting a more-homogeneous substrate surface relative to surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) analysis, thereby enabling LDI-MS to be used for the accurate and precise quantification of plasminogen in human serum in the presence of urokinase (an activator that converts plasminogen to plasmin). Relative to conventional assays, this new probe for plasmin offers the advantages of high sensitivity and selectivity and high throughput, with great potential for practical studies of fibrinolytic-related proteins. © 2013 American Chemical Society.

Chen W.-Y.,National Taiwan University | Chen L.-Y.,National Taiwan University | Ou C.-M.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University | And 3 more authors.
Analytical Chemistry | Year: 2013

We report the synthesis of fluorescent 11-mercaptoundecanoic acid-gold nanodot-liposome (11-MUA-Au ND/Lip) hybrids by incorporation of gold nanoparticles (∼3 nm) and 11-MUA molecules in hydrophobic phospholipid membranes that self-assemble to form small unilamellar vesicles. A simple and homogeneous fluorescence assay for phospholipase C (PLC) was developed on the basis of the fluorescence quenching of 11-MUA-Au ND/Lip hybrids in aqueous solution. The fluorescence of the 11-MUA-Au ND/Lip hybrids is quenched by oxygen (O2) molecules in solution, and quenching is reduced in the presence of PLC. PLC catalyzes the hydrolysis of phosphatidylcholine units from Lip to yield diacylglycerol (DAG) and phosphocholine (PC) products, leading to the decomposition of Lip. The diacylglycerol further interacts with 11-MUA-Au NDs via hydrophobic interactions, leading to inhibition of O2 quenching. The 11-MUA-Au ND/Lip probe provides a limit of detection (at a signal-to-noise ratio of 3) of 0.21 nM for PLC, with high selectivity over other proteins, enzymes, and phospholipases. We have validated the practicality of using this probe for the determination of PLC concentrations in breast cancer cells (MCF-7 and MDA-MB-231 cell lines) and nontumor cells (MCF-10A cell line), revealing that the PLC activity in the first two is at least 1.5-fold higher than that in the third. An inhibitor assay using 11-MUA-Au ND/Lip hybrids demonstrated that tricyclodecan-9-yl potassium xanthate (D609) inhibits PLC (10 nM) with an IC50 value of 3.81 ± 0.22 μM. This simple, sensitive, and selective approach holds great potential for detection of PLC in cancer cells and for the screening of anti-PLC drugs. © 2013 American Chemical Society.

Unnikrishnan B.,National Taiwan Ocean University | Wei S.-C.,National Taiwan Ocean University | Chiu W.-J.,National Taiwan Ocean University | Cang J.,Yancheng Institute of Technology | And 3 more authors.
Analyst | Year: 2014

Fluorescence quenching is an interesting phenomenon which is highly useful in developing fluorescence based sensors. A thorough understanding of the fluorescence quenching mechanism is essential to develop efficient sensors. In this work, we investigate different aspects governing the nitrite ion-induced fluorescence quenching of luminescent bovine serum albumin stabilized gold nanoclusters (BSA-Au NCs) and their application for detection of nitrite in urine. The probable events leading to photoluminescence (PL) quenching by nitrite ions were discussed on the basis of the results obtained from ultraviolet-visible (UV-Vis) absorption spectroscopy, X-ray photoelectron spectroscopy (XPS), fluorescence measurements, circular dichroism (CD) spectroscopy, zeta potential and dynamic light scattering (DLS) studies. These studies suggested that PL quenching mainly occurred through the oxidation of Au(0) atoms to Au(i) atoms in the core of BSA-Au NCs mediated by nitrite ions. The interference caused by certain species such as Hg2+, Cu 2+, CN-, S2-, glutathione, cysteine, etc. during the nitrite determination by fluorescence quenching was eliminated by using masking agents and optimising the conditions. Based on these findings we proposed a BSA-Au NC-modified membrane based sensor which would be more convenient for the real life applications such as nitrite detection in urine samples. The BSA-Au NC-modified nitrocellulose membrane (NCM) enabled the detection of nitrite at a level as low as 100 nM in aqueous solutions. This Au NC-based paper probe was validated to exhibit good performance for nitrite analysis in environmental water and urine samples, which makes it useful in practical applications. This journal is © the Partner Organisations 2014.

Steinke S.,University of Bremen | Steinke S.,Tongji University | Mohtadi M.,University of Bremen | Groeneveld J.,Alfred Wegener Institute for Polar and Marine Research | And 4 more authors.
Paleoceanography | Year: 2010

Upper water column dynamics in the southern South China Sea were reconstructed in order to track changes in the activity of the East Asian winter monsoon (EAWM) since the Last Glacial Maximum. We used the difference in the stable oxygen isotopes (δ18O) and Mg/Ca-based temperatures (DT) of surface-dwelling (G. ruber) and thermocline-dwelling (P. obliquiloculata) planktonic foraminifera and the temperature difference between alkenone-and P. obliquiloculata Mg/Ca-based temperatures to estimate the upper ocean thermal gradient at International Marine Past Global Change Study (IMAGES) core MD01-2390. Estimates of the upper ocean thermal gradient were used to reconstruct mixed layer dynamics. We find that our δ18O estimates are biased by changes in salinity and, thus, do not display a true upper ocean thermal gradient. The DT of G. ruber and P. obliquiloculata as well as the alkenone and P. obliquiloculata suggest increased surface water mixing during the late glacial, likely due to enhanced EAWM winds. Surface water mixing was weaker during the late Holocene, indicating a weaker influence of winter monsoon winds. The weakest winter monsoon activity occurred between 6.5 ka and 2.5 ka. Inferred EAWM changes since the Last Glacial Maximum coincide with EAWM changes as recorded in Chinese loess sediments. We find that the intensity of the EAWM and the East Asian summer monsoon show an inverse behavior during the last glacial and deglaciation but covaried during the middle to late Holocene. © Copyright 2010 by the American Geophysical Union.

Agency: Cordis | Branch: FP7 | Program: CP | Phase: ENV.2013.6.4-3 | Award Amount: 6.53M | Year: 2014

Coastal floods are one of the most dangerous and harmful natural hazards affecting urban areas adjacent to shorelines. Rapid urbanisation combined with climate change and poor governance means a significant increase in the risk of local surface flooding coinciding with high water levels in rivers and high tide or storm surges from the sea, posing a greater risk of devastation to coastal communities. The threats posed need to be addressed not just in terms of flood prediction and control, but taking into account governance and socio-economic issues. PEARL brings together world leading expertise in both the domain of hydro-engineering and risk reduction and management services to pool knowledge and practical experience in order to develop more sustainable risk management solutions for coastal communities focusing on present and projected extreme hydro-meteorological events. The project will examine 7 case studies from across the EU to develop a holistic risk reduction framework that can identify multi-stressor risk assessment, risk cascading processes and strengthen risk governance by enabling an active role for key actors. The research programme links risk and root cause assessment through enhanced FORIN methodology, event prediction, forecast and warning, development of adaptive structural and non-structural strategies and active stakeholder participation. The project aims to develop novel technologies and methods that can improve the early warning process and its components; it builds a pan-European knowledge base gathering real case studies and demonstrations of best practice across the EU to support capacity development for the delivery of cost-effective risk-reduction plans. Additionally, the project provides an interface to relevant ongoing tsunami work: it plugs into global databases, early warning systems and processes at WMO, and contributes to community building, development of guidelines and communication avenues at the global level through IWA.

Lin T.-R.,University of Illinois at Urbana - Champaign | Lin T.-R.,National Taiwan Ocean University | Chang S.-W.,University of Illinois at Urbana - Champaign | Chuang S.L.,University of Illinois at Urbana - Champaign | And 3 more authors.
Applied Physics Letters | Year: 2010

We investigate the effect of dielectric coating on the optical resonance of metallic bowtie nanoantennas, both theoretically and experimentally. The resonance wavelengths of the nanostructures measured by means of dark-field scattering spectroscopy are in excellent agreement with our theoretical calculations. The resonance wavelength is redshifted as the thickness of the coating layer increases, which is attributed to a longer effective optical path due to the larger refractive index of the coating than that of the air. © 2010 American Institute of Physics.

Chen C.-L.,National Taiwan Ocean University | Lee T.-Y.,Minghsin University of Science and Technology | Jan R.-M.,Minghsin University of Science and Technology | Lu C.-L.,St. John's University Taiwan
International Journal of Electrical Power and Energy Systems | Year: 2012

A novel approach based on the direct search method (DSM) is proposed for the solution of combined heat and power (CHP) dispatch problem. To deal with the mutual dependency of multiple-demand and heat-power capacity of cogeneration units, the penalty functions should be considered in DSM to enforce the corresponding violated constraints from the infeasible region into the feasible region. Many nonlinear characteristics of the generator can be handled properly in the direct search procedure. To increase the possibility of exploring the search space where the global optimal solution exists, another effective strategy based on a successive refinement search technique is also proposed to guarantee a possibly complete examination of the solution space. Numerical experiments are included to demonstrate the proposed direct search approach can obtain a higher quality solution than many existing techniques. © 2012 Elsevier Ltd. All rights reserved.

Chiou Y.-C.,National Chiayi University | Jen Y.-M.,National Taiwan Ocean University | Weng W.-K.,National Taiwan Ocean University
Engineering Failure Analysis | Year: 2011

In this paper, the effect of the tensile pre-strain on ratcheting process in 430 Stainless Steel was examined by performing a series of fully tensile-compression cyclic loading tests on the tested material with three tensile pre-strain levels or no prior deformation. The experimental results indicate that a compressive cyclic creep occurs in all applied cases for the tested material without pre-strain. Clearly, the observation reflects that the tested material exists the an-isotropic in tension and compression. Furthermore, for the tested material with various value of pre-strain, cyclic creep can also be found and the direction of creep deformation is always opposite to that of the given pre-strain. From an experimental observation on the residue deformation produced by cyclic creep, it is found that the stable total compressive creep strain scaled with increasing tensile pre-strains at the same stress amplitude condition. The material with greater compressive creep strain responded to the same applied tensile pre-strain level with higher controlled stress amplitude. Exploring the effects of the tensile pre-strain on the stable stress-strain response, this paper has been focused on those items. They are the strain range, Δε, plastic strain range, Δεp, and plastic strain energy density, ΔWP at half-life. Experimental results show that the material with different tensile pre-strains or without pre-strain had a higher response when the applied stress amplitude range was increased. Those indicated material responses have increased at increasing tensile pre-strain. In observation the effects of tensile pre-strain on the fatigue, it is found that the effect of the tensile pre-strain is to reduce the cycles to failure. A decreasing fatigue life is observed with increasing the tensile pre-strain level. In the domain of high-cycle fatigue life (in the range of 105-107 cycles), the effect of tensile pre-strain on degrading fatigue life is obvious and the degree of reducing fatigue life is governed by the magnitude of the stress amplitude. Moreover, the damage parameter based on the total plastic strain energy, Wf=∑ΔWp, can produce satisfactory life prediction results for 430 Stainless Steel with a tensile pre-strain effect under fully reversed tension-compression loading condition. © 2011.

Jen Y.-M.,National Taiwan Ocean University | Chiou Y.-C.,National Chiayi University | Yu C.-L.,Chung Hua University
Engineering Failure Analysis | Year: 2011

The crack behavior of the intermetallic compounds (IMCs) for the solder joints of electronic packages under the thermal cycling test conditions was analyzed using the finite element method in this research. A flip-chip plastic ball grid array package was selected as the analysis target. The two-dimensional in-elastic finite element method was employed to calculate the fracture mechanics parameters at the crack tip; such as the modes I and II stress intensity factors. Two locations were considered herein to initiate the crack: the first one was on the interface between the IMC and the copper pad (interfacial cracks); and the other one was at the inner part of IMC (IMC cracks). Furthermore, the effects of crack length and thickness of IMC on the crack tip parameters were also studied in this investigation. In the numerical simulation, the properties of the solder joint and the underfill were assumed to be elastic-plastic-creep and viscoelastic, respectively. The sub-modeling technique was used in the finite element analysis to reduce the computational time and the crack tip parameters were obtained using the simulated results of the displacement field near the crack tips. The results show that for both interfacial cracks and the IMC cracks, the modes I and II SIFs decrease as the length of crack increases, and the decreasing trend becomes more stable when the cracks propagate longer except for the variation of the mode II SIF for IMC cracks. Furthermore, the thickness of the IMC has slight effect on the magnitudes of SIFs under the conditions of constant crack lengths. © 2011 Elsevier Ltd.

Xu K.,Hong Kong University of Science and Technology | Huang J.-C.,National Taiwan Ocean University
Journal of Computational Physics | Year: 2010

With discretized particle velocity space, a multiscale unified gas-kinetic scheme for entire Knudsen number flows is constructed based on the BGK model. The current scheme couples closely the update of macroscopic conservative variables with the update of microscopic gas distribution function within a time step. In comparison with many existing kinetic schemes for the Boltzmann equation, the current method has no difficulty to get accurate Navier-Stokes (NS) solutions in the continuum flow regime with a time step being much larger than the particle collision time. At the same time, the rarefied flow solution, even in the free molecule limit, can be captured accurately. The unified scheme is an extension of the gas-kinetic BGK-NS scheme from the continuum flow to the rarefied regime with the discretization of particle velocity space. The success of the method is due to the un-splitting treatment of the particle transport and collision in the evaluation of local solution of the gas distribution function. For these methods which use operator splitting technique to solve the transport and collision separately, it is usually required that the time step is less than the particle collision time. This constraint basically makes these methods useless in the continuum flow regime, especially in the high Reynolds number flow simulations. Theoretically, once the physical process of particle transport and collision is modeled statistically by the kinetic Boltzmann equation, the transport and collision become continuous operators in space and time, and their numerical discretization should be done consistently. Due to its multiscale nature of the unified scheme, in the update of macroscopic flow variables, the corresponding heat flux can be modified according to any realistic Prandtl number. Subsequently, this modification effects the equilibrium state in the next time level and the update of microscopic distribution function. Therefore, instead of modifying the collision term of the BGK model, such as ES-BGK and BGK-Shakhov, the unified scheme can achieve the same goal on the numerical level directly. Many numerical tests will be used to validate the unified method. © 2010 Elsevier Inc.

Lu M.-W.,National Taiwan Ocean University | Ngou F.-H.,National Taiwan Ocean University | Chao Y.-M.,National Cheng Kung University | Lai Y.-S.,National Ilan University | And 3 more authors.
BMC Genomics | Year: 2012

Background: Grouper (Epinephelus spp) is an economically important fish species worldwide. However, viral pathogens such as nervous necrosis virus (NNV) have been causing severe infections in the fish, resulting in great loss in the grouper aquaculture industry. Yet, the understanding of the molecular mechanisms underlying the pathogenicity of NNV is still inadequate, mainly due to insufficient genomic information of the host.Results: De novo assembly of grouper transcriptome in the grouper kidney (GK) cells was conducted by using short read sequencing technology of Solexa/Illumina. A sum of 66,582 unigenes with mean length of 603 bp were obtained, and were annotated according to Gene Ontology (GO) and Clusters of Orthologous Groups (COG). In addition, the tag-based digital gene expression (DGE) system was used to investigate the gene expression and pathways associated with NNV infection in GK cells. The analysis revealed endoplasmic reticulum (ER) stress response was prominently affected in NNV-infected GK cells. A further analysis revealed an interaction between the NNV capsid protein and the ER chaperone immunoglobulin heavy-chain binding protein (BiP). Furthermore, exogenous expression of NNV capsid protein was able to induce XBP-1 mRNA splicing in vivo, suggesting a role of the capsid protein in the NNV-induced ER stress.Conclusions: Our data presents valuable genetic information for Epinephelus spp., which will benefit future study in this non-model but economically important species. The DGE profile of ER stress response in NNV-infected cells provides information of many important components associated with the protein processing in ER. Specifically, we showed that the viral capsid protein might play an important role in the ER stress response. © 2012 Lu et al.; licensee BioMed Central Ltd.

Cheng A.,National Ilan University | Lin W.-T.,National Ilan University | Huang R.,National Taiwan Ocean University
Materials and Design | Year: 2011

This study investigates the properties of cement-based composites with addition of various rock wool wastes. The rock wool wastes are an insulating material. This study used rock wool waste with a cylindrical size distribution ranging from 17 to 250μm, 30% of which is less than 150μm. Rock wool waste can be used as a suitable substitute for coarse and fine aggregates, saving on the cost of natural aggregates and minimizing the environmental impact of solid waste disposal. In addition, because the composition of rock wool waste is similar to other pozzolan materials such as fly ash, ground granulated blast-furnace slag (GGBS), and silica fume, it can be considered as a supplementary cementitious material. Experimental results show that partially replacing natural aggregates with rock wool wastes improves the compressive strength, splitting tensile strength, abrasion resistance, absorption, resistance to potential alkali reactivity, resistivity, and chloride-ion penetration of cement-based composites. These improved properties are the result of the dense structure achieved by the filling effect of pozzolanic product. Pozzolanic strength activity index (PSAI) results and scanning electron microscope (SEM) observations confirm these findings. Therefore, rock wool wastes can act as either a cementitious material or inert filler in cement-based composites, depending on the particle size. The critical size appears to be 75μm. © 2010 Elsevier Ltd.

Hsu Y.M.,National Taiwan Ocean University | Hsu Y.M.,National Ilan University | Chang C.C.,National Taiwan Ocean University
Optik | Year: 2011

This study elucidated the frequency characteristics of series photodetector frequency circuit system for detection of DNA probe ET996 marked with fluorescence dye Cy5. We developed 48 MHz series photodetector frequency circuit system with good sensitivity for fluorescence detection. In accordance with the theory of series photodetector frequency circuit system, the frequency sensitivity can be improved by adjusting circuit parameters such as A (tan θ), Cq, C0, and Cp. In this research of A adjustment, the capacitance parameter Cm of 48 MHz series photodetector frequency circuit system was adjusted to improve the frequency sensitivity for detection of fluorescence dye concentration; moreover, the bias of photodetector was also adjusted to improve the frequency sensitivity. In the optimal conditions of capacitance match and photodetector bias, the detection limit of ET996-Cy5 fluorescence dye concentration 2 pmol/L can be measured by 48 MHz sensor system. The results of fluorescence experiment also demonstrated that the frequency shift of 48 MHz sensor system was linearly related to the logarithm of fluorescence dye concentration from 200 nmol/L to 2 pmol/L. The frequency method can be applied simply and the detection limit of ET996-Cy5 fluorescence dye concentration was lower than the conventional fluorescence technique by 2 orders. © 2010 Elsevier GmbH.

Pan Y.-L.,Air force Institute of Technology Taiwan | Huang Y.-S.,National Ilan University | Jeng M.-D.,National Taiwan Ocean University
Conference Proceedings - IEEE International Conference on Systems, Man and Cybernetics | Year: 2011

Petri nets have been recognized as one of the most powerful tools for modeling FMSs. The reason is that PNs are suited well to represent FMS characteristics such as present relations, concurrence, conflict and synchronization. On the other hand, it is well known that the marking/transition-separation instances (MTSIs) method with the theory of regions has been recognized as the best (i.e. maximally permissive) policy in deadlock problems. However, its major shortcoming is the state explosion and redundant inequalities problem since the reachability graph of a plant model has to be generated when one wants to find all MTSIs. For improving these drawbacks, this paper uses the reduction method and proposes a novel concept of the crucial marking/transition-separation instances (CMTSI) which is the key of MTSIs based on Petri nets and the theory of regions. According to our experimental results, our deadlock prevention policy is more efficient in existing literatures based on the theory of regions. © 2011 IEEE.

Lee C.-L.,National Taiwan Ocean University | Huang R.,National Taiwan Ocean University | Lin W.-T.,National Ilan University | Lin W.-T.,Institute of Nuclear Energy Research of Taiwan | Weng T.-L.,Tatung University
Materials and Design | Year: 2012

The present study aimed to establish the durability indices of cement-based composites containing supplementary cementitious materials. The influences of compressive strength, permeability, and microstructure of cement-based composites containing fly ash and silica fume were discussed. The relationship between pore structure and corrosion behavior was investigated and compared. The results demonstrate that the addition of silica fume in cement-based composites resulted in a higher compressive strength, a lower absorption, a lower critical pore size, a lower chloride diffusion coefficient, and a lower corrosion rate. The composites containing 10% silica fumes performed better in permeability than composites containing 5% silica fumes, because silica fumes can narrow down the size of large capillary pores and densify the pore structure. The addition of fly ash in composites also enhanced the compressive strength and the permeability but was not as effective as silica fume. Unhydrated fly ash grains caused a looser pore structure and reduced the permeability. The combination of fly ash and silica fume enhanced the compressive strength and the permeability and specimens containing 5% silica fume and 10% fly ash had increased more in compressive strength and decreased more in permeability than specimens containing 5% silica fume or 15% fly ash. Moreover, the corrosion rate, the chloride diffusion coefficient, and the critical pore size were suitable for evaluating the durability of cement-based composites. A regression analysis found that the probability of rebar corrosion was greater than 90%, when the corrosion rate was 11.54μm/yr, the chloride diffusion coefficient was 0.62×10-12m2/s, or the critical pore size was 26.71nm. © 2012 Elsevier Ltd.

Huang Y.-R.,National Penghu University of Science and Technology | Shiau C.-Y.,National Penghu University of Science and Technology | Shiau C.-Y.,National Taiwan Ocean University | Chen H.-H.,National Ilan University | Huang B.-C.,National Penghu University of Science and Technology
Food Hydrocolloids | Year: 2011

Acid-solubilized collagen (ASC) and pepsin-solubilized collagen (PSC) were successfully extracted from the skin of balloon fish (Diodon holocanthus) with yields of 4% and 19.5% respectively (based on dry weight). According to the electrophoretic patterns, both the ASC and PSC consisted of two different α chains (α1 and α2), were characterized to be type I, and contained imino acid of 179 and 175 residues/1000 residues, respectively. The PSC had a lower content of high-molecular weight cross-links than the ASC. The ultraviolet (UV) absorption spectrum of collagens showed that the distinct absorption was between 210 and 230nm. A maximum solubility in 0.5M acetic acid was observed at pH 1-5, and a sharp decrease in solubility above 4% (w/v) in both the ASC and PSC was observed in the presence of NaCl. The denaturation temperatures (Td) of the ASC and PSC measured by viscometry were 29.01°C and 30.01°C, respectively. The maximum temperatures (Tmax) of the ASC and PSC were 29.64°C and 30.30°C, respectively. © 2011 Elsevier Ltd.

Sunoko R.,Office of Ministerial Adviser for Economic | Huang H.-W.,National Taiwan Ocean University
Marine Policy | Year: 2014

Tuna has made a significant contribution to Indonesian and world fisheries. Indonesian tuna fisheries were introduced from Japan, Taiwan and Korea. Longline fishing was introduced in 1962, and purse seine gear was first used in 1974. Many foreign vessels have reflagged to the Indonesian flag. The Indonesian government developed its own tuna fisheries and closed the chartering program in 2006. Through these efforts, Indonesia became the number one tuna production country in 2004 and has further targeted an increase in marine capture fisheries catch of 0.5%/year from 2010 to 2014. Tuna resources remain under pressure globally. The tuna regional fisheries management organizations attempt to manage tuna fisheries by strengthening conservation of stocks. To enhance international cooperation, Indonesia ratified the 1982 Convention on the Law of the Sea in 1985 and the Agreement for the Implementation of the Provisions of the United Nations Convention on the Law of the Sea of 10 December 1982 relating to Conservation and Management of Straddling Fish Stocks and Highly Migratory Fish Stocks in 2005 and became a member of Indian Ocean Tuna Commission and Commission for the Conservation of Southern Bluefin Tuna and a cooperating non-member of Western and Central Pacific Fisheries Commission in the 2000s. Consequently, Indonesia adopted domestic regulations to comply with management measures. For future sustainable development, Indonesia needs to build its capacity, improve its compliance with the tuna RFMOs' conservation and management measures, strengthen data collection, develop its products to increase their quality and diversification, and enhance its international cooperation. © 2013 Elsevier Ltd.

Huang J.-C.,National Taiwan Ocean University | Xu K.,Hong Kong University of Science and Technology | Yu P.,Hong Kong University of Science and Technology
Communications in Computational Physics | Year: 2012

With discretized particle velocity space, a multi-scale unified gas-kinetic scheme for entire Knudsen number flows has been constructed based on the kinetic model in one-dimensional case [J. Comput. Phys., vol. 229 (2010), pp. 7747-7764]. For the kinetic equation, to extend a one-dimensional scheme to multidimensional flow is not so straightforward. The major factor is that addition of one dimension in physical space causes the distribution function to become two-dimensional, rather than axially symmetric, in velocity space. In this paper, a unified gas-kinetic scheme based on the Shakhov model in two-dimensional space will be presented. Instead of particle-based modeling for the rarefied flow, such as the direct simulation Monte Carlo (DSMC) method, the philosophical principal underlying the current study is a partial-differential- equation (PDE)-based modeling. Since the valid scale of the kinetic equation and the scale of mesh size and time step may be significantly different, the gas evolution in a discretized space is modeled with the help of kinetic equation, instead of directly solving the partial differential equation. Due to the use of both hydrodynamic and kinetic scales flow physics in a gas evolution model at the cell interface, the unified scheme can basically present accurate solution in all flow regimes from the free molecule to the Navier-Stokes solutions. In comparison with the DSMC and Navier-Stokes flow solvers, the current method is much more efficient than DSMC in low speed transition and continuum flow regimes, and it has better capability than NS solver in capturing of non-equilibrium flow physics in the transition and rarefied flow regimes. As a result, the current method can be useful in the flow simulation where both continuum and rarefied flow physics needs to be resolved in a single computation. This paper will extensively evaluate the performance of the unified scheme fromfreemolecule to continuum NS solutions, and fromlow speedmicro-flow to high speed non-equilibrium aerodynamics. The test cases clearly demonstrate that the unified scheme is a reliable method for the rarefied flow computations, and the scheme provides an important tool in the study of non-equilibrium flow. © 2012 Global-Science Press.

Lin H.-C.,Academia Sinica, Taiwan | Wong Y.H.,Hong Kong University of Science and Technology | Tsang L.M.,National Taiwan Ocean University | Chu K.H.,Chinese University of Hong Kong | And 2 more authors.
Biofouling | Year: 2014

This is the first study applying Next-Generation Sequencing (NGS) technology to survey the kinds, expression location, and pattern of adhesion-related genes in a membranous-based barnacle. A total of 77,528,326 and 59,244,468 raw sequence reads of total RNA were generated from the prosoma and the basis of Tetraclita japonica formosana, respectively. In addition, 55,441 and 67,774 genes were further assembled and analyzed. The combined sequence data from both body parts generates a total of 79,833 genes of which 47.7% were shared. Homologues of barnacle cement proteins - CP-19K, -52K, and -100K - were found and all were dominantly expressed at the basis where the cement gland complex is located. This is the main area where transcripts of cement proteins and other potential adhesion-related genes were detected. The absence of another common barnacle cement protein, CP-20K, in the adult transcriptome suggested a possible life-stage restricted gene function and/or a different mechanism in adhesion between membranous-based and calcareous-based barnacles. © 2013 © 2013 Taylor & Francis.

Tsai C.-J.,National Taiwan Ocean University | Huang R.,National Taiwan Ocean University | Lin W.-T.,National Ilan University | Lin W.-T.,Institute of Nuclear Energy Research of Taiwan | Chiang H.-W.,National Taiwan Ocean University
Construction and Building Materials | Year: 2014

This study analyzed the feasibility of ground-granulated blast-furnace slag (GGBS) and ground-granulated basic oxygen furnace slag (GGBOS) blended cements according to the standard specifications of ASTM C821-09 and ASTM C595/C595M-13. Through tests, this study verified that GGBOS can be used as alkali activators for GGBS and that the mixture proportions of S4I6 and S5I5 correspond with the physical and chemical requirements specified in ASTM C595/C595M-13. Among S3I7, S4I6, and S5I5, the mixture proportion of S4I6 exhibited the highest performance by reaching 90% of the compressive strength of ordinary Portland cement mortar. © 2014 Elsevier Ltd. All rights reserved.

Tsai C.-J.,National Taiwan Ocean University | Huang R.,National Taiwan Ocean University | Lin W.-T.,National Ilan University | Lin W.-T.,Institute of Nuclear Energy Research of Taiwan | Wang H.-N.,National Taiwan Ocean University
Materials and Design | Year: 2014

Reusing waste materials and reducing carbon emissions are crucial environmental concerns. Ground granulated basic oxygen furnace slag (GGBOS) and ground granulated blast furnace slag (GGBS) are the by-products of the steel industry and has positive effects on the environment because it reduces the problems associated waste disposal. This study reused these two products to completely replace cementitious materials, thus contributing to waste recycling, reducing the production demand for cement, and mitigating carbon emissions. Twelve mixture proportions were designed in this study, including an ordinary Portland mortar (OPM) as the control group and 11 steel/iron slag blended mortar (SISBM) experimental groups for the mechanical and cementitious characteristic experiments. The optimal mixing ratio for SISBM compressive strength ranged from GGBOS (steel slag): GGBS (iron slag)=3:7 to 5:5 (by weight). At the age of 91days, the compressive strength of SISBM reached 80-90% compared with that of the control group. Based on the pH values, free-CaO, and microanalysis results, the cementitious characteristics were mainly generated because the GGBOS increased the free-CaO or Ca(OH)2 concentrations in the SISBM curing water and provided alkaline environments for Ca(OH)2 to engage in the pozzolanic reaction with the SiO2 and Al2O3 in GGBS, forming crystals such as calcium aluminum silicate hydrate, (C-A-S-H), calcium silicate hydrate (C-S-H), and calcium-magnesium-alumina-silicate (C-M-A-S), which generated strength and strengthened microstructure. © 2014 Elsevier Ltd.

Ho J.-Y.,Taiwan Typhoon and Flood Research Institute | Lee K.T.,National Taiwan Ocean University
Landslides | Year: 2016

Evaluating the performance of a physically based model for landslide prediction was conducted in this study. The model was developed based on the basis of the infinite slope instability analysis and TOPMODEL for saturated water level estimation, which enabled to predict the location and time of occurrence of shallow landslides. Field data from 2008 to 2013 in two areas vulnerable to landslide in Taiwan were collected to test the applicability of the model for landslide prediction. Three indexes including the probability of detection (POD), false alarm ratio (FAR), and threat score (TS) were adopted to assess the advantages and disadvantages of the model. The results indicated that the POD for the landslide prediction by using the proposed model was 1.00, the FAR was lower than 0.25, and the overall TS value was higher than 0.75. It is promising to apply the proposed model for landslide early warnings to reduce the loss of life and property. © 2016 Springer-Verlag Berlin Heidelberg

Wu C.-J.,National Taiwan Ocean University | Chiang K.-P.,National Taiwan Ocean University | Liu H.,Hong Kong University of Science and Technology
Journal of Experimental Marine Biology and Ecology | Year: 2010

Mesozooplankton play an important role in transporting energy from microphytoplankton and microzooplankton to higher trophic levels. However there were few studies on the diel feeding patterns and prey selectivity of mesozooplankton. We conducted feeding experiments of mesozooplankton in the East China Sea to determine their respective diel feeding patterns on diatoms, ciliates and dinoflagellates, and to assess the contribution of these prey items to mesozooplankton diet. The results showed higher mesozooplankton grazing rates on ciliates and dinoflagellates than on diatoms at the day time, and the opposite pattern at the night time. A significant prey selection was observed, in which mesozooplankton positively selected ciliates and dinoflagellates during day and diatoms at night. The different grazing reactions of mesozooplankton toward each prey item might be related to the mobility of the prey. In all, microzooplankton (ciliates and dinoflagellates) provided the majority of the mesozooplankton carbon ingestion, even at a station dominated by small pennate diatoms. In particular, dinoflagellates are an important prey of mesozooplankton in the East China Sea and their contribution to the diet of mesozooplankton is unproportionate to their abundance. © 2010 Elsevier B.V. All rights reserved.

Huang J.-C.,National Taiwan Ocean University | Xu K.,Hong Kong University of Science and Technology | Yu P.,Hong Kong University of Science and Technology
Communications in Computational Physics | Year: 2013

Due to the rapid advances inmicro-electro-mechanical systems (MEMS), the study of microflows becomes increasingly important. Currently, the molecular-based simulation techniques are the most reliable methods for rarefied flow computation, even though these methods face statistical scattering problem in the low speed limit. With discretized particle velocity space, a unified gas-kinetic scheme (UGKS) for entire Knudsen number flow has been constructed recently for flow computation. Contrary to the particle-based direct simulation Monte Carlo (DSMC) method, the unified scheme is a partial differential equation-based modeling method, where the statistical noise is totally removed. But, the common point between the DSMC and UGKS is that both methods are constructed through direct modeling in the discretized space. Due to the multiscale modeling in the unified method, i.e., the update of both macroscopic flow variables and microscopic gas distribution function, the conventional constraint of time step being less than the particle collision time inmany direct Boltzmann solvers is released here. The numerical tests show that the unified scheme is more efficient than the particle-basedmethods in the low speed rarefied flow computation. Themain purpose of the current study is to validate the accuracy of the unified scheme in the capturing of non-equilibrium flow phenomena. In the continuum and free molecular limits, the gas distribution function used in the unified scheme for the flux evaluation at a cell interface goes to the corresponding Navier-Stokes and free molecular solutions. In the transition regime, the DSMC solution will be used for the validation of UGKS results. This study shows that the unified scheme is indeed a reliable and accurate flow solver for low speed non-equilibrium flows. It not only recovers the DSMC results whenever available, but also provides high resolution results in cases where the DSMC can hardly afford the computational cost. In thermal creep flow simulation, surprising solution, such as the gas flowing from hot to cold regions along the wall surface, is observed for the first time by the unified scheme, which is confirmed later through intensive DSMC computation. © 2013 Global-Science Press.

Pan Y.-L.,Air force Institute of Technology Taiwan | Huang Y.-S.,National Ilan University | Jeng M.,National Taiwan Ocean University | Chung S.-L.,National Taiwan University of Science and Technology
International Journal of Advanced Manufacturing Technology | Year: 2013

Deadlocks are an important problem in resource allocation systems such as flexible manufacturing systems. The theory of regions and the siphon-based method are usually used in the most deadlock prevention policies. The theory of regions that can obtain a maximally permissive controller is usually considered to be a natural solution with seasonable computational cost for flexible manufacturing systems. The selective siphon method allows one to use fewer control places than the conventional one. This paper employs both methods above. The former can identify the set of curial marking/transition-separation instance; the latter can reduce the computational cost. We can infer that the novel policy is the most efficient policy than the traditional methods, and also, the maximal permissive behavior of Petri net models can still be obtained. © 2012 Springer-Verlag London Limited.

Yu C.,National Ilan University | Yen M.-H.,National Taiwan Ocean University | Hsiung P.-A.,National Chung Cheng University | Chen S.-J.,National Taiwan University
IEEE Transactions on Consumer Electronics | Year: 2011

4G and other wireless systems are currently hot topics of research and development in the communication field. Broadband wireless systems based on orthogonal frequency division multiplexing (OFDM) often require an inverse fast Fourier transform (IFFT) to produce multiple subcarriers. In this paper, we present the efficient implementation of a pipeline FFT/IFFT processor for OFDM applications. Our design adopts a single-path delay feedback style as the proposed hardware architecture. To eliminate the read-only memories (ROM's) used to store the twiddle factors, the proposed architecture applies a reconfigurable complex multiplier and bit-parallel multipliers to achieve a ROM-less FFT/IFFT processor, thus consuming lower power than the existing works. The design spends about 33.6K gates, and its power consumption is about 9.8mW at 20MHz. © 2006 IEEE.

Han T.-Y.,National Taiwan Ocean University | Lin W.-T.,Institute of Nuclear Energy Research of Taiwan | Lin W.-T.,National Ilan University | Cheng A.,National Ilan University | And 2 more authors.
Materials and Design | Year: 2012

This study evaluated the mechanical properties of cement-based composites produced with added polyolefin fibers and silica fume. Material variables included the water-cementitious ratio, the dosage of silica fume, and the length and dosage of polyolefin fiber. Researchers conducted tests on compressive strength, splitting tensile strength, direct tensile strength, resistivity, rapid chloride penetration, and initial surface absorption, and performed microscopic observation. Test results indicate that the specimens containing silica fume have higher compressive strength than the control and specimen made with fibers. The specimens with polyolefin fiber and silica fume have considerably higher tensile strength and ductility than the control and specimens made with silica fume. The specimens containing silica fume and polyolefin fiber demonstrated better resistance to chloride penetration than composites with polyolefin fiber or silica fume. For a given volume fraction, short polyolefin fiber performs better than its long counterpart in improving the properties of concrete. Specimens containing silica fume demonstrated a significant increase in resistivity and decrease in the total charge passed and absorption. Scanning electron microscopy illustrates that the polyolefin fiber acts to arrest the propagation of internal cracks. © 2011 Elsevier Ltd.

Capobianco J.A.,Drexel University | Shih W.-H.,Drexel University | Leu J.-H.,National Taiwan University | Leu J.-H.,National Taiwan Ocean University | And 2 more authors.
Biosensors and Bioelectronics | Year: 2010

We have investigated rapid, label free detection of white spot syndrome virus (WSSV) using the first longitudinal extension resonance peak of five lead-magnesium niobate-lead titanate (PMN-PT) piezoelectric microcantilever sensors (PEMS) 1050-700μm long and 850-485μm wide constructed from 8μm thick PMN-PT freestanding films. The PMN-PT PEMS were encapsulated with a 3-mercaptopropyltrimethoxysilane (MPS) insulation layer and further coated with anti-VP28 and anti-VP664 antibodies to target the WSSV virions and nucleocapsids, respectively. By inserting the antibody coated PEMS in a flowing virion or nucleocapsid suspension, label free detection of the virions and nucleocapsids were respectively achieved by monitoring the PEMS resonance frequency shift. We showed that positive label free detection of both the virion and the nucleocapsid could be achieved at a concentration of 100. virions. (nucleocapsids)/ml or 10. virions. (nucleocapsids)/100μl, comparable to the detection sensitivity of polymerase chain reaction (PCR). However, in contrast to PCR, PEMS detection was label free, in situ and rapid (less than 30. min), potentially requiring minimal or no sample preparation. © 2010 Elsevier B.V.

Lin R.-R.,National Taiwan University | Chang Y.-H.,National Taiwan Ocean University | Chao K.-M.,National Taiwan University
SIGMOD Record | Year: 2011

Keyword search is a friendly mechanism for users to identify desired information in XML databases, and LCA is a popular concept for locating the meaningful subtrees corresponding to query keywords. Among all the LCA-based approaches, MaxMatch [9] is the only one which could achieve the property of monotonicity and consistency, by outputting only contributors instead of the whole subtree. Although the MaxMatch algorithm performs efficiently in some cases, there is still room for improvement. In this paper, we first propose to improve its performance by avoiding unnecessary index accesses. We then speed up the process of subset detection, which is a core procedure for determining contributors. The resultant algorithm is called MinMap and MinMap+, respectively. At last, we analytically and empirically demonstrate the efficiency of our methods. According to our experiments, our two algorithms work better than the existing one, and MinMap+ is particularly helpful when the breadth of the tree is large and the number of keywords grows.

Chiang Y.-C.,Tzu Chi University | Hsiao S.-S.,National Taiwan Ocean University | Lin M.-C.,National Taiwan University
Proceedings of the International Offshore and Polar Engineering Conference | Year: 2011

Accurate prediction of sediment transport rates is an important element in morphological studies for the coastal environment. The purpose of this paper is to develop a quasi-three-dimensional (Q-3D) total load sediment transport formula based on the bed load and suspended load transport driven by waves and wave induced nearshore currents for the coastal area. The model consists of a two-dimensional nonlinear wave model, a two-dimensional depth integrated model for wave-driven currents with a model for undertow circulation currents and a coastal sediment transport formula with bed load and suspended load. The bed load sediment transport rate are calculated by the flow velocity coupled with wave and wave driven current near bed, and the suspended load is integrated the sediment concentration calculated by coupled velocity in vertical direction. A comparison has been carried out between the computed sediment transport rates with experimental results. The numerical results obtained are reasonably accurate within a factor of 2. Copyright © 2011 by the International Society of Offshore and Polar Engineers (ISOPE).

Lester R.,University of Texas at Austin | McIntosh K.,University of Texas at Austin | Van Avendonk H.J.A.,University of Texas at Austin | Lavier L.,University of Texas at Austin | And 2 more authors.
Earth and Planetary Science Letters | Year: 2013

New marine seismic reflection and coincident wide-angle ocean-bottom seismometer data acquired offshore Taiwan provide high-resolution constraints on the crustal structure of an incipient mountain belt during the earliest stage of arc-continent collision. The new seismic reflection image and travel-time tomography velocity model show evidence for crust of the distal southern Chinese continental margin being subducted eastward beneath the Manila trench and underplated to the accretionary wedge before collision with the southern Chinese continental shelf. The distal margin crust consists of highly extended continental crust interspersed with volcanic bodies and a high-velocity lower crustal layer of likely magmatic intrusions. The distal margin crust is 10-14. km thick outboard of the trench, but thins to 6. km thick beneath the lower slope of the Manila trench accretionary wedge. Along the lower slope of the accretionary prism, we image westward-verging imbricate thrusts and folded strata up to 10. km thick. A sharp decrease in bathymetry marks the transition from lower to upper slope, where we observe a fast (>6.0. km/s) seismic velocity anomaly at the base of the wedge that we interpret as structurally underplated crust from the distal continental margin. Our results support a model of arc-continent collision in Taiwan where the accretionary wedge is first thickened by structural underplating of distal margin crust prior to collision with the continental shelf. The crustal rocks exposed throughout the Central Range in Taiwan may be similarly derived from subducted and structurally underplated crust from the highly extended distal continental margin. © 2013 Elsevier B.V.

McIntosh K.,University of Texas at Austin | van Avendonk H.,University of Texas at Austin | Lavier L.,University of Texas at Austin | Lester W.R.,University of Texas at Austin | And 4 more authors.
Geology | Year: 2013

Seismic reflection and wide-angle data acquired across, south, and west of Taiwan show that extended to hyper-extended continental crust of the Chinese continental margin is present more than 200 km south of the shelf and is subducting at the Manila Trench. Furthermore, crustal-scale tomographic velocity models show that this crust is underthrusted to ̃15 km depth below the accretionary prism, where it then is structurally underplated to the base of the prism. We document an increasing volume of accreted crust from south to north, and in our northern transect high-velocity material of the accretionary prism can be directly linked to outcrops of Central Range basement rocks. In map view the Central Range of Taiwan is clearly contiguous with the Hengchun Peninsula and Hengchun submarine ridge to the south. Accordingly, we propose a new model in which the Central Range forms directly from the accretionary prism, including the basement core, which originates from subducted, and then accreted, extended to hyper-extended continental crust. © 2013 Geological Society of America.

Chen F.-P.,Keelung Chang Gung Memorial Hospital | Hu C.-H.,National Taiwan Ocean University | Wang K.-C.,Chang Gung University
Climacteric | Year: 2013

Objective To determine whether estrogen regulates mesenchymal stem cell (MSC) activity in bone marrow from osteoporotic postmenopausal women. Methods MSCs were collected from bone marrows which were aspirated simultaneously during iliac bone graft procedures in spine fusion surgery in osteoporotic postmenopausal women. We investigated proliferation, differentiation, osteogenic activity, and estrogen receptor (ER) α and β mRNA expression of primary culture MSCs isolated from four osteoporotic postmenopausal women, treated in vitro with or without 17β-estradiol. The expression of alkaline phosphatase (ALP), osteocalcin, interleukin-6, ERα and ERβ mRNA was evaluated. Results The expression of ALP and osteocalcin mRNA was detected during the cultures of MSCs and was observed to increase up to day 20. As compared with MSCs not treated with estradiol, a significant increase in DNA content, ERα mRNA, and ALP mRNA expression was observed in cultures with estradiol. The mRNA expression of osteocalcin and interleukin-6 was significantly lower in MSCs treated with estradiol than those without estradiol. There was no significant difference in the mRNA expression of ERβ between MSCs cultured with and without estradiol. Conclusions In the proper environment, MSCs from osteoporotic women can differentiate into osteoblasts and estrogen enhances the osteogenic activity possibly via ERα activity. © 2012 International Menopause Society.

Chang M.-H.,National Taiwan Ocean University | Tang T.Y.,National Taiwan University | Ho C.-R.,National Taiwan Ocean University | Chao S.-Y.,University of Cambridge
Journal of Geophysical Research: Oceans | Year: 2013

The wake of Green Island was investigated in the alongshore flowing Kuroshio east of Taiwan, where current speeds range from 1 to 1.5 ms -1. Vertical profiling with shipboard lowered acoustic Doppler current profiler and conductivity-temperature-depth profiler revealed sizable anomalies in flow and water characteristics in the lee of Green Island. Two different stages of wake evolution were observed from two shipboard surveys. In the first stage, a recirculation developed leeward of the island, followed by a wavy (wave-like) tail that resembled a weak vortex street. In the second stage, a cold eddy probably originating from the leeward side of the island showed up 14 km downstream of the island. The wake water was colder, saltier, higher in chlorophyll-a concentration, and produced isopycnal doming up to 60 m. In the recirculation area, the relative vorticity, either positive or negative, was 10 times of planetary vorticity, and the horizontal divergence or convergence was O (10-4 s-1) on average. Flow divergence and convergence in the wake were expected to form upwelling and downwelling zones, producing a vertical circulation that vertically displaces isotherms. High inverse Richardson number, produced by strong vertical shear of horizontal currents, was associated with intense overturning events in the wake. High vertical shear of horizontal currents drove the mixing. The dissipation rate of turbulent kinetic energy in the overturn regions is O (10-7-10-5) W Kg -1; the corresponding eddy diffusivity is O (10-3-10 -1) m2 s-1. The wake water properties are vertically diffused via upwelling and turbulence and can be delivered downstream through eddy shedding or advection. The extent of downstream influence remains to be investigated. © 2013. American Geophysical Union. All Rights Reserved.

Lin H.-J.,National Taiwan Ocean University | Lien Y.-C.,National Taiwan Ocean University | Hsu C.-H.,National Taiwan University
Analytical Biochemistry | Year: 2010

Spermidine/spermine N1-acetyltransferase 1 (SSAT1) is a key enzyme that catalyzes the catabolism of polyamines. SSAT1 is a very important enzyme because it not only maintains the homeostasis of polyamines but also is involved in many physiological and pathological events. As such, a rapid assay of SSAT1 activity is valuable in drug screening and clinical diagnostics. Here, we report a novel colorimetric assay for monitoring SSAT1 activity in zebrafish (zSSAT1). In comparison with the available SSAT1 assays, this new method is cost-effective and simple. The optimal zSSAT1 activity was obtained below 55°C in a mild alkaline environment. The Km values of zSSAT1 for spermidine and spermine are 55 and 182μM, respectively, whereas putrescine is not a good substrate for zSSAT1. In addition to enzyme kinetic studies, the colorimetric assay was also used to detect the cellular activity of SSAT1. Thus, the current method is a reliable assay for determining SSAT1 activity with many potential applications in medical biology. © 2010 Elsevier Inc.

Lien R.-C.,University of Washington | Sanford T.B.,University of Washington | Jan S.,National Taiwan University | Chang M.-H.,National Taiwan Ocean University | Ma B.B.,University of Washington
Journal of Marine Research | Year: 2013

Strong semidiurnal internal tides are observed on the continental slope of the East China Sea (ECS) using an array of subsurface moorings and EM-APEX floats. A Princeton Ocean Model (POM) is used to simulate the effects of stratification profiles on the generation and propagation of M2 internal tides; model simulations are compared with observations. On the ECS continental slope northeast of Taiwan, the semidiurnal barotropic tidal current flows nearly perpendicular to the shelf break and continental slope, favoring the generation of internal tides. Both the critical slope analysis and numerical model results suggest multiple generation sites on the continental slope, shelf break and around North Mien- Hua Canyon. Unique high-wavenumber semidiurnal internal tides with a dominant vertical scale of ~ 100 m are found on the continental slope. The high-wavenumber semidiurnal internal tides appear in a form of spatially coherent shear layers across the ECS slope. They propagate vertically both upward and downward. Patches of strong energy and shear at a typical vertical scale of O(50 m) are present at the intersections of the upward and downward propagating high-wavenumber internal tides. The strong shear of high-wavenumber semidiurnal tides could play an important role in triggering shear instability on the ECS slope. The semidiurnal internal tidal energy flux, primarily in low wavenumbers, on the ECS slope, exhibits strong temporal and spatial variations. The observed depth integrated energy flux is 3.0-10.7 kW m-1, mostly seaward from the continental shelf/slope. The POM model predicts similar seaward energy fluxes at a slightly weaker magnitude, 1.0-7.2 kW m-1. The difference may be due to the absence of mesoscale processes in the model, e.g., the Kuroshio Current and eddies, the assumed horizontally uniform stratification profiles, insufficient model resolution for the abrupt canyon bathymetry, and the lack of the other major semidiurnal tidal constituent, S2, in the model. On the ECS slope, the total energy in the internal wave continuum, between 0.3 cph (beyond semidiurnal tidal harmonics) and the buoyancy frequency, is 6-13 times that of the Garrett-Munk model, presumably as a result of the energy cascade from strong inertial waves and internal tides in the region. © 2013 Ren-Chieh Lien, Thomas B. Sanford, Sen Jan, Ming-Huei Chang and Barry B. Ma.

Chen D.-Z.,National Taiwan University | Huang M.-H.,National Taiwan University | Hsieh H.-C.,National Taiwan University | Lin C.-P.,National Taiwan Ocean University
Journal of Informetrics | Year: 2011

This study uses bibliographic coupling to identify missing relevant patent links, in order to construct a comprehensive citation network. Missing citation links can be added by taking the missing relevant patent links into account. The Pareto principle is used to determine the threshold of bibliographic coupling strength, in order to identify the missing relevant patent links. Comparisons between the original patent citation network and the comprehensive patent citation network with the missing relevant patent links are illustrated at both the patent and assignee levels. Light emitting diode (LED) illuminating technology is chosen as the case study. The relationships between the patents and the assignees are obviously enhanced after adding the missing relevant patent links. The results show that the growth rates on both the total number and the average number of links have apparently improved at the patent level. At the assignee level, the number of linked assignees and the average number of links between two assignees are increased. The differences between the two citation networks are further examined by means of the Freeman vertex betweenness centrality and Johnson's hierarchical clustering. The patents with more new links to other patents have distinct results in terms of the Freeman vertex betweenness centrality. The enhancement of links among patents also results in different clustering. © 2011.

Liu C.-S.,National Taiwan University | Kuo C.-L.,National Taiwan Ocean University
CMES - Computer Modeling in Engineering and Sciences | Year: 2011

In this paper, the solutions of inverse Cauchy problems for quasilinear elliptic equations are resorted to an unusual mixed group-preserving scheme (MGPS). The bottom of a finite rectangle is imposed by overspecified boundary data, and we seek unknown data on the top side. The spring-damping regularization method (SDRM) is introduced by converting the governing equation into a new one, which includes a spring term and a damping term. The SDRM can further stabilize the inverse Cauchy problems, such that we can apply a direct numerical integration method to solve them by using the MGPS. Several numerical examples are examined to show that the SDRM+MGPS can overcome the ill-posed behavior of the inverse Cauchy problem. The present algorithm has good efficiency and stability against the disturbance from random noise, even with an intensity being large up to 10%, and the computational time is very saving. Copyright © 2011 Tech Science Press.

Chen F.-F.,Taiwan Power | Chou S.-C.,National Taiwan University | Lu T.-K.,National Taiwan Ocean University
Energy Policy | Year: 2013

For this study, we constructed the following three case scenarios based on the Taiwanese government's energy policy: a normal scenario, the 2008 "Sustainable Energy Policy Convention" scenario, and the 2011 "New Energy Policy" scenario. We then employed a long-term Generation Expansion Planning (GEP) optimization model to compare the three case scenarios' energy mix for power generation for the next å15 years to further explore their possible impact on the electricity sector. The results provide a reference for forming future energy policies and developing strategic responses. © 2013 Elsevier Ltd.

Zhang Y.-M.,Shandong University of Technology | Gu Y.,Shandong University of Technology | Chen J.-T.,National Taiwan Ocean University
Computational Mechanics | Year: 2011

For a long time, most of the current numerical methods, including the finite element method, have not been efficient to analyze stress fields of very thin structures, such as the problems of thin coatings and their interfacial/internal mechanics. In this paper, the boundary element method for 2-D elastostatic problems is studied for the analysis of multicoating systems. The nearly singular integrals, which is the primary obstacle associated with the BEM formulations, are dealt with efficiently by using a semi-analytical algorithm. The proposed semi-analytical integral formulas, compared with current analytical methods in the BEM literature, are suitable for high-order geometry elements when nearly singular integrals need to be calculated. Owing to the employment of the curved surface elements, only a small number of elements need to be divided along the boundary, and high accuracy can be achieved without increasing more computational efforts. For the test problems studied, very promising results are obtained when the thickness of coated layers is in the orders of 10-6-10-9, which is sufficient for modeling most coated systems in the micro- or nano-scales. © Springer-Verlag 2010.

Chang R.,National Taiwan Ocean University | Leung P.T.,National Taiwan Ocean University | Leung P.T.,Academia Sinica, Taiwan | Leung P.T.,Portland State University | And 2 more authors.
Optics Express | Year: 2014

We perform theoretical studies on the plasmonic enhancement for the Forster resonance energy transfer (FRET) between a donor and an acceptor molecule in the vicinity of a metallic particle or cavity, with focus on the possible role of the addition of a clad layer of gain material can play in such a process. The results show that while the plasmonic resonances can be shifted with higher order plasmonic enhancements emerged in the presence of such a layer of gain material, optimal enhancement of the FRET rate can be achieved when gain just balances with the loss in the metal. This then leads to the existence of an optimal thickness for the gain material layer, for both particle and cavity enhancement. In addition, it is observed that the FRET efficiency can always be increased with the coating of the gain material even at the dipole plasmonic resonance when nonradiative transfer from the donor to the metal is high, provided that the gain level is not beyond a certain critical value. ©2014 Optical Society of America

Chan M.H.,National Taiwan University | Chen J.Y.,National Taiwan University | Lin T.Y.,National Taiwan Ocean University | Chen Y.F.,National Taiwan University
Applied Physics Letters | Year: 2012

The emission from ZnO nanorods/poly(3-hexylthiophene) (P3HT) heterostructures with type II band alignment has been investigated. The additional emission due to the formation of the heterojunction around 950 nm has been found and attributed to the type II transition related to the recombination of electrons in conduction band of ZnO and holes in highest occupied molecular orbital band of P3HT. The consistency of excitation power density dependent photoluminescence (PL) spectra with the theoretical prediction offers a firm evidences for the type II transition. In addition, lifetime of P3HT measured by time-resolved PL also strongly supports that the infrared light indeed arises from the type II transition. Our results shown here provide the first direct evidence of the type II band alignment in ZnO nanorods/P3HT heterostructure, which should be very useful for the realization of underpinned mechanism of the developed optoelectronic devices. © 2012 American Institute of Physics.

Shih H.Y.,National Taiwan University | Chen Y.F.,National Taiwan University | Lin T.Y.,National Taiwan Ocean University
Applied Physics Letters | Year: 2012

The influence of an external stress on the optical properties of InGaN/GaN multiple quantum disks (MQDs) has been investigated. As a transversal force is applied on the MQDs, both photoluminescence and Raman scattering spectra are altered due to the piezoelectric potential accompanied by the quantum confined Stark effect. Quite interestingly, it is found that the optical spectra possess a sixfold symmetry about the c-axis. This intriguing phenomenon can be attributed to the inherent nature of hexagonal lattice as well as the good flexibility of the composite consisting of polydimethylsiloxane and MQDs. Our results can provide an alternative route to optimize and extend the application of nitride-based devices. © 2012 American Institute of Physics.

Xu W.,Xiamen University | Xu W.,State Oceanic Administration | Pang K.-L.,National Taiwan Ocean University | Luo Z.-H.,State Oceanic Administration
Microbial Ecology | Year: 2014

Knowledge about the presence and ecological significance of bacteria and archaea in the deep-sea environments has been well recognized, but the eukaryotic microorganisms, such as fungi, have rarely been reported. The present study investigated the composition and abundance of fungal community in the deep-sea sediments of the Pacific Ocean. In this study, a total of 1,947 internal transcribed spacer (ITS) regions of fungal rRNA gene clones were recovered from five sediment samples at the Pacific Ocean (water depths ranging from 5,017 to 6,986 m) using three different PCR primer sets. There were 16, 17, and 15 different operational taxonomic units (OTUs) identified from fungal-universal, Ascomycota-, and Basidiomycota-specific clone libraries, respectively. Majority of the recovered sequences belonged to diverse phylotypes of Ascomycota (25 phylotypes) and Basidiomycota (18 phylotypes). The multiple primer approach totally recovered 27 phylotypes which showed low similarities (≤97 %) with available fungal sequences in the GenBank, suggesting possible new fungal taxa occurring in the deep-sea environments or belonging to taxa not represented in the GenBank. Our results also recovered high fungal LSU rRNA gene copy numbers (3.52 × 106 to 5.23 × 107copies/g wet sediment) from the Pacific Ocean sediment samples, suggesting that the fungi might be involved in important ecological functions in the deep-sea environments. © 2014, Springer Science+Business Media New York.

Dai M.-K.,National Taiwan University | Lian J.-T.,National Taiwan Ocean University | Lin T.-Y.,National Taiwan Ocean University | Chen Y.-F.,National Taiwan University
Journal of Materials Chemistry C | Year: 2013

Transparent and flexible thin film transistors (TFTs) with high performance based on solution processed graphene nanosheets (GNSs)-amorphous indium-gallium-zinc-oxide (a-IGZO) composites have been developed. A high electron mobility of 23.8 cm2 V-1 s-1 has been achieved, which is about thirty times higher than those of the pristine a-IGZO TFTs (0.82 cm2 V-1 s-1) and hydrogenated amorphous silicon (<1 cm2 V-1 s-1). The on/off current ratio remains in a high order of 106 demonstrating the sustainability of the TFT devices. In addition, transparent GNSs-a-IGZO TFTs with a Ta2O5 dielectric layer show superior resistance to mechanical bending with the variation of only 8% in mobility after 100 times of repeated cyclic bending compared with the degradation of more than 70% for the pristine a-IGZO device. Our results demonstrate that GNSs not only play an important role in forming a conducting network in the active matrix, but also enhance the mechanical bending stability of GNSs-a-IGZO composites. It therefore paves a key step to develop large-scale applications for next-generation transparent and flexible electronics. © 2013 The Royal Society of Chemistry.

Chang K.-H.,National Taiwan University | Tsaur D.-H.,National Taiwan Ocean University | Huang L.-H.,National Taiwan University
Coastal Engineering | Year: 2012

In 1999, the U.S. Army has launched a revolutionary concept in V-shaped breakwaters to reduce the impact of elevated sea states during humanitarian (or military) operations. Barriers of this type provide a sheltered region in the interior of the V. Herein a modified V-shaped model, intended as a supplement to the original concept, is presented. The corresponding linearized diffraction problem is solved by an effective technique and then an improved series solution is newly derived. Appropriate basis functions are selected to correctly capture the singular behaviors in velocity fields near the salient corners and cusped edges of the breakwater. Comparisons with the results of the usual eigenfunction expansion method reveal the efficiency and accuracy of the present approach. Influences of associated parameters on the waveheight distributions are illustrated and discussed. The quickly convergent method proposed herein not only provides a reliable benchmark for assessing the results of other numerical methods, but also has a promising potential to attack problems implicating troublesome tip and corner singularities. © 2012 Elsevier B.V.

Shiang Y.-C.,National Taiwan University | Hsu C.-L.,National Taiwan Ocean University | Huang C.-C.,National Taiwan Ocean University | Chang H.-T.,National Taiwan University
Angewandte Chemie - International Edition | Year: 2011

DNA hybridization of thrombin-binding aptamers (TBAs) to form a self-assembled arranged monolayer on gold nanoparticles (AuNPs) was used to control the coagulation activity of thrombin. The hTBA 15/hTBA 29/cDNA-AuNPs provided flexibility and a suitable orientation and distance between the hTBA 15 and hTBA 29 units for bivalent binding, allowing strong interactions with thrombin and extremely high anticoagulant potency. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Lai Y.-C.,National Taiwan University | Hsu F.-C.,National United University | Chen J.-Y.,National Taiwan University | He J.-H.,National Taiwan University | And 5 more authors.
Advanced Materials | Year: 2013

A newly designed transferable and flexible label-like organic memory based on a graphene electrode behaves like a sticker, and can be readily placed on desired substrates or devices for diversified purposes. The memory label reveals excellent performance despite its physical presentation. This may greatly extend the memory applications in various advanced electronics and provide a simple scheme to integrate with other electronics. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hsiao B.,National Taiwan University | Chern C.-C.,National Taiwan University | Yu M.-M.,National Taiwan Ocean University
Decision Support Systems | Year: 2012

This paper presents an alternative approach for evaluating the efficiency of integrated circuit (IC) design firms. In doing so, it accounts for differences between technology groups containing one or more design firms, and input and output factors to prevent influences of scale (e.g., firm size). Specifically, we employed a directional distance function approach to data envelopment analysis in order to evaluate inefficiency scores and differences among groups based on input and output factors. We found the efficiency of Taiwan's IC design firms to be dependent not only on firm size but also on R&D expenditure and patent revenue. Our findings suggest that these factors significantly influence the technical efficiency of Taiwan IC design. Furthermore, by focusing on technology gaps, we offer some suggestions for the different groups based on group-frontier and meta-frontier analyses. Finally, using the results of these analyses, we extend the global results of this study, presenting ways to further improve efficiency. © 2012 Elsevier B.V. All rights reserved.

Nupan B.,Prince of Songkla University | Phongdara A.,Prince of Songkla University | Saengsakda M.,Prince of Songkla University | Leu J.H.,National Taiwan Ocean University | Lo C.F.,National Taiwan University
Developmental and Comparative Immunology | Year: 2011

Fortilin plays an important role in anti-apoptotic mechanisms and cell proliferation in many eukaryotic organisms. This work confirmed previous reports that Sf9 can support the replication of white spot syndrome virus (WSSV) genomic material by using immunohistochemistry with a specific antibody to detect the immediate early gene 1 (ie1) and by amplification of WSSV DNA and mRNA products. Using this insect-cell model system, we show that overexpression of Pm-fortilin in Sf9 cells inhibited the expression of WSSV early genes and late genes (WSSV- DNA polymerase, VP15 and VP28) but not an immediate early gene ie1. This is the first time that an insect cell line has been used to demonstrate interaction between a shrimp gene and genes of a shrimp virus. © 2010 Elsevier Ltd.

Liu S.-H.,National Taiwan University | He S.-P.,National Taiwan Ocean University | Chiang M.-T.,National Taiwan Ocean University
Journal of Agricultural and Food Chemistry | Year: 2012

This study was designed to investigate the effects of long-term feeding of chitosan on postprandial lipid response and lipid metabolism in a high-sucrose (HS)-diet-impaired glucose-tolerant rat model. As the results, HS-diet-fed rats supplemented with 5 and 7% chitosan in diets for 9 weeks had lower postprandial plasma total cholesterol (TC) levels, but 7% chitosan in the diet had higher postprandial plasma triglyceride (TG) and TG-rich lipoprotein TG levels. Supplementation of chitosan significantly decreased the postprandial ratio of apolipoprotein B (apoB)48/apoB100 in TG-rich lipoprotein fractions of HS-diet-fed rats. Long-term supplementation of 5 and 7% chitosan in diets for 16 weeks had lower plasma TC, low-density lipoprotein cholesterol (LDL-C) + very low density lipoprotein cholesterol (VLDL-C), TC/high-density lipoprotein (HDL-C) ratio, leptin, and tumor necrosis factor-α (TNF-α) levels in HS-diet-fed rats. Moreover, it was noticed that the VLDL receptor (VLDLR) protein expression in skeletal muscles of HS-diet-fed rats was significantly decreased, which could be significantly reversed by supplementation of 5 and 7% chitosan. Rats supplemented with 7% chitosan in the diet significantly elevated the lipolysis rate and decreased the accumulation of TG in epididymal fat pads of HS-diet-fed rats. The plasma angiopoietin-like 4 (ANGPTL4) protein expression was not affected in HS-diet-fed rats, but it was significantly increased in 7% chitosan-supplemented HS-diet-fed rats. Taken together, these results indicate that supplementation of chitosan in the diet can improve the impairment of lipid metabolism in a HS-diet-fed rat model, but long-term high-dose chitosan feeding may enhance postprandial plasma TG and TG-rich lipoprotein TG levels in HS-diet-fed rats through an ANGPTL4-regulated pathway. © 2012 American Chemical Society.

Tsay L.-W.,National Taiwan Ocean University | Hsu C.-L.,National Taiwan Ocean University | Chen C.,National Taiwan University
ISIJ International | Year: 2010

Notched tensile tests of Ti-6AI-6V-2Sn welds, which were subjected to distinct post-weld heat treatments (PWHTs), were carried out in air at 150, 300 and 450°C. The results were compared with those of mill-annealed base metal (MB) specimens tested at same temperatures. The notched tensile strength (NTS) of the MB specimens decreased significantly with increasing temperature. Moreover, the welds with high hardness showed notch brittleness at room temperature but had a higher NTS than the MB specimen. The presence of grain boundary α layer promoted grain boundary shear, therefore, reduced its notch brittleness at room temperature for the weld with the PWHT at 704°C (the W-704 specimen). A lack of deformation compatibility at the interfaces between the α and β phases caused interfacial separations in the MB specimen as well as void formation in the W-704 specimen, leading to the low NTS of these specimens at elevated temperatures.

Tsai S.-W.,Chang Gung University | Chen C.-C.,Chang Gung University | Liou H.-M.,National Taiwan Ocean University | Hsu F.-Y.,National Taiwan Ocean University
Journal of Biomedical Materials Research - Part A | Year: 2010

Numerous studies about bone matrix fabrication focus on how the species and concentrations of components affect the cellular response. However, there are few studies that investigate how the related spatial arrangement of the components influences cellular activity. The aim of this work was to develop a novel method to biomimetically manufacture a three-dimensional mineral bone matrix and study the effect of apatite-collagen-chondroitin sulfate (CS) microspheres on the adhesion rate and activity of osteoblast-like cells. Although previous studies used a crosslinking agent or lyophilized methods to fabricated three-dimensional collagen microspheres, we produced beads composed of collagen and CS under mild reaction conditions. This process not only maintains collagen self-assembly into fibrils with a D-periodic pattern ability but also simultaneously introduces two major native bone matrix elements, collagen and CS, into the beads. Furthermore, we mimic the native in vivo bone matrix formation process by the direct nucleation and growth of apatite crystals on collagen fibrils. The apatite crystals are similar in composition to human bone mineral via X-ray diffraction and energy-dispersive X-ray spectrometric analysis. The cellular attachment rate of MG63 osteoblast-like cells is significantly higher for collagen-CSapatite gel beads than for collagen-CS gel beads. In addition, with regard to the osteoblast bioactivity, we observed that alkaline phosphatase activity of MG63 cells on the collagen-CS-apatite gel beads higher than on the collagen-CS gel beads on day 14. © 2009 Wiley Periodicals, Inc.

Tsai C.-C.,National Kaohsiung Marine University | Liu C.-S.,National Taiwan University | Yeih W.-C.,National Taiwan Ocean University
CMES - Computer Modeling in Engineering and Sciences | Year: 2010

The fictitious time integration method (FTIM) previously developed by Liu and Atluri (2008a) is combined with the method of fundamental solutions and the Chebyshev polynomials to solve Poisson-type nonlinear PDEs. The method of fundamental solutions with Chebyshev polynomials (MFS-CP) is an exponentially-convergent meshless numerical method which is able to solving nonhomogeneous partial differential equations if the fundamental solution and the analytical particular solutions of the considered operator are known. In this study, the MFS-CP is extended to solve Poisson-type nonlinear PDEs by using the FTIM. In the solution procedure, the FTIM is introduced to convert a Poisson-type nonlinear PDE into a sequence of linear nonhomogeneous modified Helmholtz equations which are then formally solved by the MFS-CP. Several numerical experiments were carried out to validate the proposed methods. © 2010 Tech Science Press.

Huang C.-C.,National Taiwan Ocean University | Hung Y.-L.,National Taiwan Ocean University | Shiang Y.-C.,National Taiwan University | Lin T.-Y.,Ocean University of China | And 3 more authors.
Chemistry - An Asian Journal | Year: 2010

We have employed mannosemodified gold nanodots (Man-Au NDs) as a luminescence sensor for the detection of the thyroid-cancer marker thyroglobulin (Tg) in homogeneous solutions. The luminescent Man-Au NDs are prepared through the reaction of 2.9 nm-diameter gold nanoparticles (Au NPs) with 11-mercapto-3,6,9-trioxaundecyl-a-d-mannopyranoside (Man-RSH) under the irradiation of a lightemitting diode (LED). We have found that the irradiation enhances the quantum yield (~11%), alters the emission wavelength and lifetimes, and shortens the preparation time. A luminescence assay has been developed for Tg based on the competition between Tg and Man-Au NDs for the interaction with the concanavalin A (Con A). Because luminescence quenching of the Man-Au NDs by Con A is inhibited by Tg selectivity, we have obtained a highly sensitive and selective assay for Tg. © 2010 Wiley-VCH Verlag GmbH&Co. KGaA, Weinheim.

Chen C.-H.,National Taiwan Ocean University | Hsieh C.-H.,Asia University, Taiwan | Hwang D.-F.,National Taiwan Ocean University | Hwang D.-F.,Asia University, Taiwan
Food Control | Year: 2012

Cyprinidae fish are widely distributed in Taiwan, and processed products made from them are favored by consumers. To identify the species used for these processed products, complete mitochondrial cytochrome b genes (cyt. b, 1141 bp) of 8 Cyprinidae were established. Then, a rapid PCR-RFLP method was used to amplify a 426 bp fragment of cyt. b using primer set Lnew1/Hnew1, and the fragment was co-digested with NlaIII and BstXI. The results show that using this PCR-RFLP technique for the species identification of the 8 Cyprinidae was successful. The method was further applied to investigate 16 commercial samples of processed Cyprinidae products from traditional markets. The results indicate that 9 of the samples were Carassius auratus auratus, Cyprinus carpio carpio, or Ctenopharyngodon idella. The other 6 samples did not belong to the Cyprinidae family according to PCR-RFLP. These samples were further analyzed with the forensically informative nucleotide sequencing (FINS) and BLAST methods. The results show that these 6 processed products were Oreochromis spp., a monophyletic fish group. The last commercial product could not be amplified to obtain a 426 bp fragment, so its species remains unknown. This study shows that PCR-RFLP and FINS can be used to identify processed products fraudulently labeled as Cyprinidae. © 2012 Elsevier Ltd.

Wei C.M.,National Taiwan University | Shih H.Y.,National Taiwan University | Chen Y.F.,National Taiwan University | Lin T.Y.,National Taiwan Ocean University
Applied Physics Letters | Year: 2011

The magnetoelectric effect has been demonstrated based on the composite of InGaN/GaN multiple quantum wells (MQWs) and FeCo thin film. By applying an external magnetic field, the ferromagnetic layer will be deformed due to magnetostriction. This deformation is transmitted to the piezoelectric layers and results in piezoelectric effect, which induces electric polarization in the piezoelectric layers. The induced electric polarization changes the strain and the built-in internal electric field in the InGaN/GaN MQWs and therefore, the optical properties of the InGaN/GaN MQWs change. The results shown here open up a possibility for the application of nitride semiconductors in magneto-optical and magnetoelectric engineering. © 2011 American Institute of Physics.

Shih H.-Y.,National Taiwan University | Cheng S.-H.,National Taiwan University | Lian J.-K.,National Taiwan University | Lin T.-Y.,National Taiwan Ocean University | Chen Y.-F.,National Taiwan University
Optics Express | Year: 2012

Based on the composite consisting of ZnO nanorods (NRs) grown on InGaN/GaN multiple quantum wells (MQWs), we have demonstrated a novel light-emitting device (LED) that has the capability to emit dual beam radiations. Interestingly, the relative intensity between the dual emissions is able to be manipulated by their polarizations. The underlying mechanism can be well understood in terms of the anisotropic optical properties arising from the geometric structures of constituent nanoscale materials. The results shown here may be extended to many other nanocomposite systems and pave a new pathway to create LEDs with tunable properties. © 2012 Optical Society of America.

Kuo C.-L.,National Taiwan Ocean University | Chang J.-R.,National Taiwan Ocean University | Liu C.-S.,National Taiwan University
Numerical Heat Transfer, Part B: Fundamentals | Year: 2013

This article is aimed to reconstruct a time-dependent heat source for a one-dimensional heat conduction equation. The extra measurement data are used to transform the original equation into a homogeneous equation with three-point boundary conditions. Then the modified polynomial expansion method is developed to deal with the resulting three-point boundary-value problem. By considering the characteristic length, the modified polynomial expansion method can obtain a convergent series solution and improve the stability of the algorithm. The accuracy and efficiency of the present method are validated by comparing the estimating results with those of designed examples even under noisy measurement data. © 2013 Taylor and Francis Group, LLC.

Huang C.-Y.,National Taiwan University | Lin G.-C.,National Taiwan Ocean University | Wu Y.-J.,National Taiwan Ocean University | Lin T.-Y.,National Taiwan Ocean University | And 2 more authors.
Journal of Physical Chemistry C | Year: 2011

Light harvesting from In2O3 nanopushpins as an antireflection layer has been investigated. We report on the growth of In 2O3 nanopushpins on silicon solar cells by catalyst-free and improved two-zone chemical vapor deposition in order to provide a suitable growth environment with low temperature and high growth rate for practical applications. On the basis of spectral reflectance and cell responsivity measurements, we show that In2O3 nanopushpins provide efficient light trapping properties. A dramatic enhancement in short-circuit current (from 19.65 to 24.73 mA/cm2) with In2O3 nanopushpins than that of the bulk silicon wafer is observed. The solar cells incorporated with In2O3 nanopushpins therefore open an excellent alternative to serve as an antireflection layer for the enhancement of light harvesting and cell efficiency. © 2011 American Chemical Society.

Chiang Y.-C.,Tzu Chi University | Hsiao S.-S.,National Taiwan Ocean University | Lin M.-C.,National Taiwan University
Journal of Marine Science and Technology | Year: 2010

Numerical modeling of coastal morphodynamic evolution is a powerful tool for the planning and design of coastal engineering. The coastal morphological modeling system is based on the sediment conservation law, which couples modules for waves, wave-driven currents, and sediment transport rates. The numerical scheme for the sediment conservation law and nonlinear coupling between these modules can lead to dispersions, diffusions, spurious oscillations and stability problems that are still not well developed. In this paper, the bedslope updating techniques, oscillation removal schemes, and 2-step, 3-time-level temporal discretization are employed to avoid oscillations and improve the stability of the coastal morphological model with accuracy up to O(Δ2,Δx5,Δy5). Finally, the model shows good performance for coastal areas with complex topography.

Chen S.-J.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University | Chang H.-T.,National Taiwan University
Talanta | Year: 2010

In this study, we have developed a simple, cost-effective, label-free fluorescence analytical assay - comprising an adenosine-binding aptamer (AptAdo), platelet-derived growth factor (PDGF)-binding aptamer (AptPDGF), gold nanoparticles (Au NPs), and the DNA-binding dye Oligreen (OG) - for the determination of adenosine. AptAdo and AptPDGF are for the recognition of adenosine and for the amplification of fluorescence signal, respectively. The presence of adenosine induces the conformational switch of the AptAdo from coiled to a G-quadruplex structure, leading to the less binding of AptAdo onto the surface of Au NPs. The more the adenosine is present, the less the amount of AptAdo is adsorbed, resulting in the fluorescence change of the aptamer-OG complexes. When using a mixture of AptAdo (15.0 nM), Au NPs (0.1 nM), and OG (0.05×) in 5.0 mM phosphate (pH 7.4), this sensor provides the limit of detection of 70.0 nM for adenosine at a signal-to-noise ratio of 3. The LOD for adenosine is down to 5.5 nM when using AptAdo modified Au NPs (AptAdo-Au NPs) and AptPDGF for the enrichment of adenosine and amplification of fluorescence signal of OG, respectively. The practicality of the present sensor has been validated by the determination of adenosine in diluted urine samples, showing its advantages of simplicity, selectivity, sensitivity, and minimal matrix interference. © 2009 Elsevier B.V.

Chen C.-K.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University | Chang H.-T.,National Taiwan University
Biosensors and Bioelectronics | Year: 2010

We unveil a novel, label-free, colorimetric assay - using fibrinogen (Fib) and gold nanoparticles (Au NPs) - for the highly selective and sensitive detection of thrombin. Addition of fibrinogen to a solution of Au NPs (average diameter: 56 nm) led to ready conjugation, forming Fib-Au NPs through electrostatic and hydrophobic interactions. Introduction of thrombin (a serine protease) into the Fib-Au NPs solutions in the presence of excess fibrinogen induced the formation of insoluble fibrillar fibrin-Au NPs agglutinates through the polymerization of the unconjugated and conjugated fibrinogen. After centrifugation, the absorbance at 532 nm of the supernatants decreased upon increasing the concentration of thrombin. This Fib-Au NP probe provides high sensitivity [limit of detection (LOD): 0.04 pM] for thrombin, with remarkable selectivity over other proteins and proteases. The range of linearity for the absorbance against the thrombin concentration was 0.1-10 pM (R2 = 0.96). This approach provides an LOD for thrombin that is lower than those obtainable using other nanomaterial- and aptamer-based detection methods. We validated the utility of this Fib-Au NP probe through separate analyses of thrombin and Factor Xa at picomolar levels in plasma samples-without the need for sample pretreatment. This technique appears to have practical potential in the diagnosis of diseases associated with coagulation abnormalities and cancers (e.g., pulmonary metastasis). © 2010 Elsevier B.V. All rights reserved.

Chiang C.-K.,National Taiwan University | Yang Z.,National Taiwan University | Lin Y.-W.,National Taiwan University | Chen W.-T.,National Taiwan University | And 2 more authors.
Analytical Chemistry | Year: 2010

We have analyzed peptides, proteins, and protein-drug complexes through surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) using HgTe nanostructures as matrixes. We investigated the effects of several parameters, including the concentration of the HgTe nanostructures, the pH of the buffer, and the concentration of salt, on the performance of this system. When HgTe nanostructures are used as matrixes, [M + H]+ ions were the dominant signals. Relative to other commonly used nanomaterials, HgTe nanostructures provided lower background signals from metal clusters, fewer fragment ions, less interference from alkali-adducted analyte ions, and a higher mass range (up to 150-000 Da). The present approach provides limits of detection for angiotensin I and bovine serum albumin of 200 pM and 14 nM, respectively, with great reproducibility (RSD: <25%). We validated the applicability of this method through the detections of (i) the recombinant proteins that were transformed in E. coli, (ii) the specific complex between bovine serum albumin and l-tryptophan, and (iii) a carbonic anhydrase- acetazolamide complex. Our results suggest that this novel and simple SALDI-MS approach using HgTe nanostructures as matrixes might open several new ways for proteomics and the analysis of drug-protein complexes. © 2010 American Chemical Society.

Tang K.-C.,National Taiwan University | Chang M.-J.,Feng Chia University | Lin T.-Y.,National Taiwan University | Pan H.-A.,National Taiwan University | And 5 more authors.
Journal of the American Chemical Society | Year: 2011

Using 7-hydroxy-1-indanone as a prototype (I), which exhibits excited-state intramolecular proton transfer (ESIPT), chemical modification has been performed at C(2)-C(3) positions by fusing benzene (molecule II) and naphthalene rings, (molecule III). I undergoes an ultrafast rate of ESIPT, resulting in a unique tautomer emission (λ max ∼530 nm), whereas excited-state equilibrium is established for both II and III, as supported by the dual emission and the associated relaxation dynamics. The forward ESIPT (normal to proton-transfer tautomer species) rates for II and III are deduced to be (30 ps) -1 and (22 ps) -1, respectively, while the backward ESIPT rates are (11 ps) -1 and (48 ps) -1. The ESIPT equilibrium constants are thus calculated to be 0.37 and 2.2 for II and III, respectively, giving a corresponding free energy change of 0.59 and -0.47 kcal/mol between normal and tautomer species. For III, normal and tautomer emissions in solid are maximized at 435 and 580 nm, respectively, achieving a white light generation with Commission Internationale de l'Eclairage (CIE) (0.30, 0.27). An organic light-emitting diode based on III is also successfully fabricated with maximum brightness of 665 cd m -2 at 20 V (885 mA cm -2) and the CIE coordinates of (0.26, 0.35). The results provide the proof of concept that the white light generation can be achieved in a single ESIPT system. © 2011 American Chemical Society.

Shiang Y.-C.,National Taiwan University | Lin C.-A.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University | Chang H.-T.,National Taiwan University
Analyst | Year: 2011

We have employed protein A-modified gold nanodots (PA-Au NDs) as a luminescence sensor for the detection of human immunoglobulin G (hIgG) in homogeneous solutions. The luminescent PA-Au NDs were prepared simply by mixing protein A with the luminescent Au NDs (average diameter: ca. 1.8 nm). The specific interactions that occur between protein A and hIgG allowed us to use the PA-Au NDs to detect hIgG selectively. Under optimal conditions [10 nM PA-Au NDs (two protein A molecules per Au ND), 5.0 mM phosphate buffer solution, pH 7.4], the PA-Au ND probe detected hIgG with high sensitivity (limit of detection = 10 nM) and remarkable selectivity (>50-fold) over other proteins. In an assay that took advantage of the competition between protein G and the PA-Au NDs for IgG, we detected protein G at concentrations as low as 85 nM. This PA-Au ND probe allowed determination of the hIgG concentration in plasma samples without any need for sample pretreatment. Our results exhibited a good linear correlation (R2 = 0.97) with those obtained using an enzyme-linked immunosorbent assay. Our simple, sensitive, and selective approach appears to hold practical potential for use in the clinical diagnosis of immune diseases associated with changes in hIgG levels. © 2011 The Royal Society of Chemistry.

Huang Z.-J.,National Taiwan Ocean University | Kang S.-T.,National Taiwan University | Leu J.-H.,National Taiwan Ocean University | Chen L.-L.,National Taiwan Ocean University
Fish and Shellfish Immunology | Year: 2013

The white spot syndrome virus (WSSV) has had a serious economic impact on the global shrimp aquaculture industry in the past two decades. Although research has clarified a lot about its genome and structure, the mechanism of how WSSV enters a cell is still unclear. In this study to determine this mechanism, primary cultured hemocytes were used as an experimental model to observe the process of WSSV entry because the stable shrimp cell lines for WSSV infection are lacking. After labeling virions and endosomes with fluorescent dyes followed by observation with a confocal microscope, the results show that the WSSV colocalizes with early endosomes. Hemocytes are further treated with different endocytic inhibitors, methyl-β-cyclodextrin (MβCD) and chlorpromazine (CPZ). WSSV still can be detected in the hemocytes treated with CPZ, but not in the hemocytes treated with MβCD. Thus, we conclude that WSSV adopts the caveolae-mediated endocytosis to enter the shrimp cell. © 2013 Elsevier Ltd.

Leu J.-H.,National Taiwan Ocean University | Lin S.-J.,National Taiwan University | Huang J.-Y.,National Taiwan University | Chen T.-C.,National Taiwan University | Lo C.-F.,National Taiwan University
Fish and Shellfish Immunology | Year: 2013

White spot syndrome virus (WSSV) is an enveloped, large dsDNA virus that mainly infects penaeid shrimp, causing serious damage to the shrimp aquaculture industry. Like other animal viruses, WSSV infection induces apoptosis. Although this occurs even in by-stander cells that are free of WSSV virions, apoptosis is generally regarded as a kind of antiviral immune response. To counter this response, WSSV has evolved several different strategies. From the presently available literature, we construct a model of how the host and virus both attempt to regulate apoptosis to their respective advantage. The basic sequence of events is as follows: first, when a WSSV infection occurs, cellular sensors detect the invading virus, and activate signaling pathways that lead to (1) the expression of pro-apoptosis proteins, including PmCasp (an effecter caspase), MjCaspase (an initiator caspase) and voltage-dependent anion channel (VDAC); and (2) mitochondrial changes, including the induction of mitochondrial membrane permeabilization and increased oxidative stress. These events initiate the apoptosis program. Meanwhile, WSSV begins to express its genes, including two anti-apoptosis proteins: AAP-1, which is a direct caspase inhibitor, and WSV222, which is an E3 ubiquitin ligase that blocks apoptosis through the ubiquitin-mediated degradation of shrimp TSL protein (an apoptosis inducer). WSSV also induces the expression of a shrimp anti-apoptosis protein, Pm-fortilin, which can act on Bax to inhibit mitochondria-triggered apoptosis. This is a life and death struggle because the virus needs to prevent apoptosis in order to replicate. If WSSV succeeds in replicating in sufficient numbers, this will result in the death of the infected penaeid shrimp host. © 2012 Elsevier Ltd.

Fu Z.-J.,Hohai University | Chen W.,Hohai University | Chen J.-T.,National Taiwan Ocean University | Qu W.-Z.,Hohai University
CMES - Computer Modeling in Engineering and Sciences | Year: 2014

This study investigates the singular boundary method (SBM) with three regularization approaches for solving 2D and 3D exterior wave problems. The singular boundary method is a recent meshless boundary collocation method, which introduces the concept of source intensity factors to eliminate the singularity of the fundamental solutions. Recently, three approaches, the inverse interpolation technique (IIT), the semi-analytical technique with boundary IIT (SAT1) and the semi-analytical technique with integral mean value (SAT2), have been proposed to determine the source intensity factors for removing the singularities of Helmholtz fundamental solutions at origin. This study compares numerical accuracy and stability of these three approaches on some benchmark examples under 2D and 3D exterior wave radiation and scattering problems. Numerical investigations show that SAT1>IIT>SAT2 in numercial accuracy and SAT2>SAT1>IIT in numerical stability. Then the SBM with SAT1 is applied to water wave-structure interaction and SH wave scattering problem. For water wave-structure interaction, numerical results show that both the porosity of the cylinder sidewall and the disorder arrangement have a great effect on the free-surface elevations in the vicinity of the wave structure. For SH wave scattering by a semi-circular hill, the focusing phenomenon is revisited. Copyright © 2014 Tech Science Press.

Tsay L.W.,National Taiwan Ocean University | Lin Y.J.,National Taiwan Ocean University | Chen C.,National Taiwan University
Corrosion Science | Year: 2012

The effects of rolling temperature (25 and 150°C) and sensitization treatment (650°C/1h) on the susceptibility to sulfide stress corrosion cracking of 304L specimens were investigated. Regardless of the rolling temperature, the low hydrogen embrittlement (HE) susceptibility was associated with a high α'-martensite content and/or deformability near the notch-fractured location. In contrast, sensitization treatment increased the HE susceptibility of all rolled specimens. Additionally, cracks were observed only on the cold-rolled specimen in the U-bend immersion tests. The superior performance of the warm-rolled specimen in saturated H 2S solution was confirmed by both notched tensile and U-bend immersion tests. © 2012 Elsevier Ltd.

Liao Y.-J.,National Taiwan University | Shiang Y.-C.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University | Chang H.-T.,National Taiwan University
Langmuir | Year: 2012

We prepared thrombin-binding aptamer-conjugated gold nanoparticles (TBA-Au NPs) through a molecularly imprinted (MP) approach, which provide highly efficient inhibition activity toward the polymerization of fibrinogen. Au NPs (diameter, 13 nm), 15-mer thrombin-binding aptamer (TBA 15) with different thymidine linkers, and 29-mer thrombin-binding aptamer (TBA 29) with different thymidine linkers (Tn) in the presence of thrombin (Thr) as a template were used to prepare MP-Thr-TBA 15/TBA 29-Tn-Au NPs. Thrombin molecules were then removed from Au NPs surfaces by treating with 100 mM Tris-NaOH (pH ca. 13.0) to form MP-TBA 15/TBA 29-Tn-Au NPs. The length of the thymidine linkers and TBA density on Au NPs surfaces have strong impact on the orientation, flexibility, and stability of MP-TBA 15/TBA 29-Tn-Au NPs, leading to their stronger binding strength with thrombin. MP-TBA 15/TBA 29-T 15-Au NPs (ca. 42 TBA 15 and 42 TBA 29 molecules per Au NP; 15-mer thymidine on aptamer terminal) provided the highest binding affinity toward thrombin with a dissociation constant of 5.2 - 10 -11 M. As a result, they had 8 times higher anticoagulant (inhibitory) potency relative to TBA 15/TBA 29-T 15-Au NPs (prepared in the absence of thrombin). We further conducted thrombin clotting time (TCT) measurements in plasma samples and found that MP-TBA 15/TBA 29-T 15-Au NPs had greater anticoagulation activity relative to four commercial drugs (heparin, argatroban, hirudin, and warfarin). In addition, we demonstrated that thrombin induced the formation of aggregates from MP-TBA 15-T 15-Au NPs and MP-TBA 29-T 15-Au NPs, thereby allowing the colorimetric detection of thrombin at the nanomolar level in serum samples. Our result demonstrates that our simple molecularly imprinted approach can be applied for preparing various functional nanomaterials to control enzyme activity and targeting important proteins. © 2012 American Chemical Society.

Chen J.-T.,National Taiwan Ocean University | Huang W.-S.,National Taiwan Ocean University | Lee J.-W.,National Taiwan Ocean University | Hong H.-K.,National Taiwan University
Engineering Analysis with Boundary Elements | Year: 2015

Dual boundary integral equations for the N-dimensional Laplace problems with a smooth boundary are derived by using the contour approach surrounding the singularity. The potentials resulted from the four kernel functions in the dual formulation have different properties across the smooth boundary. For the generalization, we focus on the N-dimensional Laplace equation. The Hadamard principal value (H.P.V.) is derived naturally and is composed of two parts, the Cauchy principal value (C.P.V.) and an unbounded boundary term. The hypersingular integral is not a divergent integral since we can collect the C.P.V. and the unbounded term together. Besides, the weighting of the free term contributed by different kernels is also examined. Finally, a special case of the four-dimensional Laplace equation is implemented and the free term, for any dimension are obtained. The contributions of the free terms for the boundary normal derivative of potential due to the single (L kernel) and the double (M kernel) layer potentials are 1/N and (N - 1)/N, respectively. It is an interesting phenomenon that the hypersingular kernel contributes more than the singular kernel, and, in addition, the former also yields an unbounded boundary term. © 2015 Elsevier Ltd. All rights reserved.

Liu C.-S.,National Taiwan University | Yeih W.,National Taiwan Ocean University | Atluri S.N.,University of California at Irvine
CMES - Computer Modeling in Engineering and Sciences | Year: 2010

When problems in engineering and science are discretized, algebraic equations appear naturally. In a recent paper by Liu and Atluri, non-linear algebraic equations (NAEs) were transformed into a nonlinear system of ODEs, which were then integrated by a method labelled as the Fictitious Time Integration Method (FTIM). In this paper, the FTIM is enhanced, by using the concept of a repellor in the theory of nonlinear dynamical systems, to situations where multiple-solutions exist. We label this enhanced method as MSFTIM. MSFTIM is applied and illustrated in this paper through solving boundary-layer problems, boundary-value problems, and eigenvalue problems with multiple solutions. © 2010 Tech Science Press.

Tsay L.W.,National Taiwan Ocean University | Hsu C.L.,National Taiwan Ocean University | Chen C.,National Taiwan University
Materials Chemistry and Physics | Year: 2010

Notched tensile tests of Ti-4.5Al-3V-2Fe-2Mo welds with distinct post-weld heat treatments (PWHTs) were carried out at 150, 300, and 450 °C. The results were also compared with those of mill-annealed base metal (the MB specimen) tested at the same conditions. The as-welded (AW) specimen exhibited notch brittleness even when tested at 450 °C, partly due to a fast age-hardening response at the test temperature. In contrast, the weld with PWHT at 482 °C exhibited severe notch brittleness at room temperature but showed an increase in strength and ductility as the temperature increased. In general, the weld with PWHT at 704 °C (the W-704 specimen), AW and MB specimens displayed reduced notched tensile strength (NTS) with increasing temperature. At elevated temperatures, the W-704 specimen with coarse α + β structures in a basket-weave form also demonstrated superior NTS to the MB specimen with banded α + β structures. © 2009 Elsevier B.V. All rights reserved.

Lai Y.-C.,National Taiwan University | Wang Y.-X.,National Taiwan University | Huang Y.-C.,National Taiwan Ocean University | Lin T.-Y.,National Taiwan Ocean University | And 3 more authors.
Advanced Functional Materials | Year: 2014

Fabrication of functional devices on arbitrary non-conventional substrates has significant advantages for broadening devices applications and the development of soft electronic systems such as flexible, stretchable, wearable, and epidermal electronic modules. Information storage device is one of crucial electronic elements in modern digital circuitries. Herein, a re-writable, transferable, and flexible sticker-type organic memory on universal substrates is demonstrated through a facile and cost-effective one-step strategy. The organic memory sticker based on the graphene electrode grown by chemical vapor deposition consists of a blending composite of polymer (poly (methyl methacrylate) (PMMA):poly (3-hexylthiophene) (P3HT) in chlorobenzene (CB) fabricated by mature solution processes and facilities. By combining with the mechanical elastic of organic material and graphene electrode, the sticker-type organic memory can be easily tagged on non-planar or flexible substrates after etching away the supporting metal. Particularly, the new attachable sticker-type memory processes a unique feature of re-programmable capability. It is believed that the universal substrate selectivity of the sticker-type organic memory with re-writable characteristic revealed here may greatly enlarge information storage devices in immense areas and advance the future functional soft circuitries. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Liu C.-S.,Hohai University | Liu C.-S.,National Taiwan Ocean University
Computers and Mathematics with Applications | Year: 2016

The polynomial expansion method together with the collocation technique is a cheap yet simple method to solve the Navier equations of elasticity, which is easily arranged to satisfy the governing equations and boundary conditions pointwise. In this paper we propose a novel numerical algorithm for the solution of an overspecified/underspecified Cauchy problem of linear elasticity in an arbitrary plane domain, by using the multiple-scale Pascal polynomial expansion method (MSPEM), of which the scales are determined a priori by the collocation points, according to the idea of equilibrated matrix. In the numerical tests of a direct problem as well as the overspecified/underspecified Cauchy problems, the MSPEM is very accurate and stable against large relative noise up to 20% for the unknown displacements recovery problem, and up to 100% absolute noise for the recovery of unknown loading force. The present method is convergent very fast for most cases within 100 iteration steps. © 2016 Elsevier Ltd

Shiang Y.-C.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University | Chen W.-Y.,National Taiwan University | Chen P.-C.,National Taiwan University | Chang H.-T.,National Taiwan University
Journal of Materials Chemistry | Year: 2012

Fluorescent gold and silver nanoclusters are interesting sensing materials because of their molecule-like optical properties, easy preparation, and biocompatibility. In this review, we highlight the chemical and optical properties of fluorescent gold and silver nanoclusters, as well as their preparation and applications in biomolecular analysis and cell imaging. This journal is © The Royal Society of Chemistry.

Chen H.-F.,National Taiwan University | Wang T.-C.,National Taiwan University | Hung W.-Y.,National Taiwan Ocean University | Chiu H.-C.,National Taiwan Ocean University | And 2 more authors.
Journal of Materials Chemistry | Year: 2012

We designed and synthesized a series of spiro-configured bipolar hosts (CSC, DSD, TST, and NSN) comprising electron-transporting 4,5-diazafluorene and hole-transporting carbazole or diarylamine with thorough characterizations of their thermal, photophysical, electrochemical properties, and carrier mobilities. Time-of-flight (TOF) measurements and single-carrier devices revealed these compounds had good hole and electron mobilities (10 -5 - 10 -7 cm 2 V -1 s -1) together with promising physical properties, rendering them good host materials for efficient electrophosphorescence. The green PhOLED with (PPy) 2Ir(acac) as the emitter incorporating CSC as the host exhibited a remarkable high brightness of 260000 cd m -2 at 2400 mA cm -2 (11 V) with the maximum external quantum efficiency (η ext) of 17.1%, the η ext remained as high as 15.4% under a high brightness of 10000 cd m -2 at a low operating voltage of 5.1 V even without p-i-n device configuration. The NSN-based PhOLED with the red dopant Os(bpftz) 2(PPhMe 2) 2 has a maximum brightness of 77900 cd m -2 at 1100 mA cm -2 (10 V) with the maximum η ext of 19.5%. The η ext remained as high as 19.1% under a practical brightness of 1000 cd m -2 (4.6 V). These results suggest that the spiro-configured D-A hosts are well-suited for achieving highly efficient PhOLED with limited efficiencies roll-off. © 2012 The Royal Society of Chemistry.

Lin H.-C.,Academia Sinica, Taiwan | Lin H.-C.,National Taiwan University | Ho S.-C.,Academia Sinica, Taiwan | Chen Y.-Y.,Academia Sinica, Taiwan | And 5 more authors.
Science | Year: 2015

Selenocysteine (Sec) is translated from the codon UGA, typically a termination signal. Codon duality extends the genetic code; however, the coexistence of two competing UGA-decoding mechanisms immediately compromises proteome fidelity. Selenium availability tunes the reassignment of UGA to Sec. We report a CRL2 ubiquitin ligase-mediated protein quality-control system that specifically eliminates truncated proteins that result from reassignment failures. Exposing the peptide immediately N-terminal to Sec, a CRL2 recognition degron, promotes protein degradation. Sec incorporation destroys the degron, protecting read-through proteins from detection by CRL2. Our findings reveal a coupling between directed translation termination and proteolysis-assisted protein quality control, as well as a cellular strategy to cope with fluctuations in organismal selenium intake. © 2015, American Association for the Advancement of Science. All rights reserved.

Wang K.-C.,Academia Sinica, Taiwan | Wang K.-C.,National Taiwan University | Lyu S.-Y.,Academia Sinica, Taiwan | Liu Y.-C.,Academia Sinica, Taiwan | And 4 more authors.
Acta Crystallographica Section D: Biological Crystallography | Year: 2014

Utilization of N-acetylhexosamine in bifidobacteria requires the specific lacto-N-biose/galacto-N-biose pathway, a pathway differing from the Leloir pathway while establishing symbiosis between humans and bifidobacteria. The gene lnpB in the pathway encodes a novel hexosamine kinase NahK, which catalyzes the formation of N-acetylhexosamine 1-phosphate (GlcNAc-1P/GalNAc-1P). In this report, seven three-dimensional structures of NahK in complex with GlcNAc, GalNAc, GlcNAc-1P, GlcNAc/AMPPNP and GlcNAc-1P/ADP from both Bifidobacterium longum (JCM1217) and B. infantis (ATCC15697) were solved at resolutions of 1.5-2.2Å. NahK is a monomer in solution, and its polypeptide folds in a crescent-like architecture subdivided into two domains by a deep cleft. The NahK structures presented here represent the first multiple reaction complexes of the enzyme. This structural information reveals the molecular basis for the recognition of the given substrates and products, GlcNAc/GalNAc, GlcNAc-1P/GalNAc-1P, ATP/ADP and Mg2+, and provides insights into the catalytic mechanism, enabling NahK and mutants thereof to form a choice of biocatalysts for enzymatic and chemoenzymatic synthesis of carbohydrates. © 2014 International Union Of Crystallography.

Zhang Y.-M.,Shandong University of Technology | Zhang Y.-M.,Dalian University of Technology | Qu W.-Z.,Hohai University | Chen J.-T.,National Taiwan Ocean University
Engineering Analysis with Boundary Elements | Year: 2013

A new boundary element method is developed for solving thin-body thermoelastic problems in this paper. Firstly, the novel regularized boundary integral equations (BIEs) containing indirect unknowns are proposed to cancel the singularity of fundamental solutions. Secondly, a general nonlinear transformation available for high-order geometry elements is introduced in order to remove or damp out the near singularity of fundamental solutions, which is crucial for accurate solutions of thin-body problems. Finally, the domain integrals arising in both displacement and its derivative integral equations, caused by the thermal loads, are regularized using a semi-analytical technique. Six benchmark examples are examined. Results indicate that the proposed method is accurate, convergent and computationally efficient. The proposed method is a competitive alternative to existing methods for solving thin-walled thermoelastic problems. © 2012 Elsevier Ltd.

Huang T.-L.,Chang Gung University | Sung M.-L.,Chang Gung University | Chen T.-Y.,National Taiwan Ocean University
Proteome Science | Year: 2014

Introduction: Platelet activation is related to the psychopathology of major depression. We attempted to search and identify protein biomarkers from the platelets of patients with major depression. High resolution two-dimensional Differential Gel Electrophoresis (2D-DIGE), the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), Western blot, and bioinformatic tools were applied to examine the platelet proteins of 10 patients with major depression and 10 healthy controls.Results: The levels of 8 proteins were significantly different between the patients with major depression in the acute phase and healthy controls. The levels of protein disulfide-isomerase A3 (PDIA3) and F-actin-capping protein subunit beta (CAPZB) were higher in patients with major depression than in healthy controls. The levels of fibrinogen beta chain (FIBB), fibrinogen gamma chain (FIBG), retinoic acid receptor beta (RARB), glutathione peroxidase 1 (GPX1), SH3 domain-containing protein 19 (SH319), and T-complex protein 1 subunit beta (TCPB) were lower in patients with major depression than in healthy controls.Conclusions: Platelet provided valuable information about the pathways and processes of inflammation/immunity, oxidative stress, and neurogenesis, related to major depression. © 2014 Huang et al.; licensee BioMed Central Ltd.

Chen C.-J.,National Taiwan Ocean University | Chu T.-H.,National Taiwan University | Lin C.-L.,National Cheng Kung University | Jou Z.-C.,Darfon Electronics Corporation
IEEE Transactions on Circuits and Systems II: Express Briefs | Year: 2010

Nonradiative wireless power transfer using magnetically coupled coils is studied in order to transfer a predetermined amount of power at the maximum efficiency. Accordingly, a conceptual wireless power transfer system and a tuning method are presented. Such a study is essential for effectively exploiting the inherent ability of a given pair of coupled coils. With the equations for inductance and resistance calculations, the system performance is evaluated and verified with well-known experimental results and circuit simulations. © 2006 IEEE.

Chang C.-C.,National Taiwan University | Kuo Y.-F.,National Taiwan University | Wang J.-C.,National Taiwan Ocean University | Chen S.-L.,National Taiwan University
Applied Thermal Engineering | Year: 2010

This article experimentally and numerically investigates the thermal performance of a large-scale motor with a capacity of 2350 kW. The large-scale motor consists of a centrifugal fan, two axial fans, a shaft, a stator, a rotor and a heat exchanger with 637 cooling tubes. The test rigs are set up to measure the performance of the fans and the temperature distributions of the motor. The models of the fan and motor have been implemented in a Fluent software package to predict the flow and temperature fields inside the motor. The calculated results show good agreement with the measured data. In order to improve the motor thermal performance, several methods have been adopted, which are aiming to enhance the fan performance by changing the geometry, to redesign a new heat exchanger with guide vanes, and to optimize the distance between the axial fans. The modified design can decrease the temperature rise by 6 °C in both the stator and rotor. © 2010 Elsevier Ltd. All rights reserved.

Periasamy A.P.,National Taiwan University | Liu J.,Liaocheng University | Lin H.-M.,National Taiwan Ocean University | Chang H.-T.,National Taiwan University
Journal of Materials Chemistry A | Year: 2013

Hierarchical copper nanowires (Cu NWs) having structures of rose-like stems with nano-thorns, with an average length and width of 6 ± 4 μm and 100 ± 15 nm, respectively, are prepared through a simple hydrothermal approach. In the presence of catechin, nano-thorn growth readily occurs from the side faces (200) of rose-like stems that are partially covered with ethylenediamine (EDA) that acts as a complexing agent for Cu2+. The size and morphology of Cu NWs are highly dependent on the concentrations of catechin, EDA, and reaction time. The hydrothermal approach is further applied to the preparation of a Cu NW decorated reduced graphene oxide (Cu NW@RGO) composite in the presence of graphene oxide (GO) and catechin as a reducing agent. The Cu NWs in Cu NW@RGO have a similar structure to that of Cu NWs prepared in bulk solution, with an average length and width of 4 ± 2 μm and 200 ± 4 nm, respectively. The Cu NW@RGO relative to Cu NWs has greater dispersion in aqueous solution, mainly because of greater hydrophilicity of RGO than Cu NW. The Cu NW@RGO-GCE relative to the bare glassy carbon electrode (GCE) (236 Ω) and Cu NW-GCE (322 Ω) has a small charge transfer resistance value (87 Ω), because of the facile electron transfer ability and good conductivity provided by RGO. The Cu NW@RGO composite featuring low-cost, high durability, low onset potential (ca. 0.48 V) and high mass activity (1.11 mA μg-1) exhibits a superior catalytic activity for methanol oxidation in an alkaline medium. © The Royal Society of Chemistry 2013.

Zhou X.,Hohai University | Zheng J.,Hohai University | Doong D.-J.,National Taiwan Ocean University | Demirbilek Z.,U.S. Army
Ocean Engineering | Year: 2013

Coastal phenomena at river estuary areas will be affected by global climate change conditions. This paper reports on analysis of the sea level rise (SLR) from the last 50 years of tide stations data along the East Asia and Chinese coasts and morphodynamic changes in the Yangtze River Estuary determined for four SLR rates. Long-term tide records of 58 stations from the Permanent Service for Mean Sea Level (PSMSL) database were analyzed to develop projected estimates of the SLR trends. The calculated average rate of SLR is 2.67 mm/yr along the East Asia coasts, and 2.89 mm/yr along the Chinese coasts, with a 5.44 mm/yr estimate at the Yangtze Estuary, which is nearly three times the global average. Including the joint effects of the SLR and coastal land subsidence, the relative SLR will range from 1.5 m to 2.7 m at the Yangtze Estuary by the end of this century. Under the conditions of dry season water discharge, numerical simulation results show that the flood and ebb velocities would decrease for the SLR greater than 0.18 m. The areas of influence will increase proportional to the scale of SLR, significantly changing deposition conditions in this river estuary. Simulation results indicate that more dramatic morphological changes occur in the estuary during the dry conditions as compared to wet conditions. During the wet seasons, significant topography changes occur only for the SLR greater than 0.59 m, with an associated increase in the current velocities outside the river mouth. This may induce severe beach erosion problems, especially along the northern coasts of the Yangtze Estuary. © 2013 Elsevier Ltd. All rights reserved.

Kuo L.-W.,National Taiwan University | Song S.-R.,National Taiwan University | Huang L.,National Taiwan University | Yeh E.-C.,National Taiwan Normal University | Chen H.-F.,National Taiwan Ocean University
Tectonophysics | Year: 2011

To investigate the coseismic frictional temperature in seismogenic fault zones, we examine the characteristics of clays in the Chelungpu-fault zones with isothermal heating experiments, scanning electron microscope coupled to an energy dispersive spectrometer (SEM/EDX), and thermogravimetry analysis (TGA). In the TCDP case (Taiwan Chelungpu fault Drilling Project), three fault zones of the Chelungpu-fault system were identified at the depth of 1111. m, 1153. m, and 1222. m (described as FZ1111, FZ1153, and FZ1222 hereafter), respectively. The clay mineral assemblages of FZ1111 show evidence of melting, and the temperature in a ~. 2. cm band within the black gouge zone is estimated to be from 900°C to 1100°C by comparing the SEM images of in situ natural samples with those of heated materials, and the finding of no recrystallization of kaolinite-amorphous aluminosilicates-spinel in the fault samples. The clay mineral assemblages of FZ1153 suggested that kaolinite has been broken down by the thermal decomposition/dehydroxylation but chlorite has not. The clay characteristics and results of SEM/EDX and TGA constrain the faulting temperature from 500°C to 900°C, with a spatial distribution up to ~. 1.3. m. The clay characteristics of FZ1222 indicated that clays were changed by experiencing high temperature acid fluids, instead of thermal decomposition/dehydroxylation processes, and that the temperature is localized in ~. 2. cm and ranges from 350°C to 500°C, the lowest temperature among three fault zones. The estimates of temperature ranges, and thermal anomaly intervals among three fault zones provide important information and constraints on the physical and chemical processes, coseismic dynamic weakening mechanism, and earthquake energy budget in the future. © 2011 Elsevier B.V.

Lee M.-A.,National Taiwan Ocean University | Chang Y.,National Cheng Kung University | Shimada T.,Tohoku University
Deep-Sea Research Part II: Topical Studies in Oceanography | Year: 2015

This study demonstrates the seasonal evolution of fine-scale sea-surface temperature (SST) fronts in the East China Sea (ECS) by applying an entropy-based edge detection algorithm to high-resolution (1.1. km) satellite SST images obtained between 1996 and 2009. Five major SST fronts are detected. The Jiangsu Fronts exist all year round along the 20-m isobath near the Jiangsu coast. In summer, the Jiangsu Fronts exhibit several frontal bands, closely corresponding to the shape of radial sand ridges off the Jiangsu coast. The Yangtze Bank Front forms a ring-shaped structure off the Yangtze River estuary in winter, and creates a boundary between the cold shelf water over the Yangtze Shoal and the warm Kuroshio water. The China Coastal Front evolves in winter along the 50-m isobath from the northern ECS southwestward into the Taiwan Strait. The Kuroshio Front is enhanced to the northeast of Taiwan between the 100-m and 200-m isobaths. The Cheju Island Front emerges along the southern coast of the Korean Peninsula and extends between Cheju Strait and Tsushima Strait, and is sustained in the summer months. Thus, this study reveals hitherto undescribed fine-scale structures of SST fronts, and shows their seasonal variations and relation to the bathymetry. © 2014 Elsevier Ltd.

Two antipatharian-associated species of the pontoniine shrimp genus Cuapetes Clark, C. lanceolatus sp. nov. and C. nilandensis (Borradaile), are reported from the Ryukyu Islands, Japan. The new species appears closest to C. akiensis (Kubo) and C. calmani (Tattersall), but differs considerably from the latter two species in the shape of the rostrum and the length of upper antennular flagellum. Cuapetes nilandensis, the type species of the genus, is recorded from Japanese waters for the first time. Copyright © 2012. Magnolia Press.

Marin I.,RAS A.N. Severtsov Institute of Ecology and Evolution | Chan T.-Y.,National Taiwan Ocean University | Okuno J.,Natural History Museum and Institute
Zootaxa | Year: 2012

Four species of the crinoid-associated pontoniine shrimps of the "Laomenes amboinensis (De Man, 1888)" species group were collected in the Philippines PANGLAO 2004 and Ryukyu KUMEJIMA 2009 Expeditions. Two of them, L. pestrushka n. sp. from the Ryukyus and L. gyrophthalmus n. sp. from the Philippines, are new to science. The two others, L. cornutus (Borradaile, 1915) and L. holthuisi Marin & Okuno, 2010, are rarely collected species. Copyright © 2012. Magnolia Press.

Hung W.-Y.,National Taiwan Ocean University | Wang T.-C.,National Taiwan University | Chiu H.-C.,National Taiwan Ocean University | Chen H.-F.,National Taiwan University | Wong K.-T.,National Taiwan University
Physical Chemistry Chemical Physics | Year: 2010

A spiro-configured bipolar molecule (CSC) that possesses high triplet energy, suitable energy levels, and balanced ambipolar carrier mobilities was successfully applied as an efficient host material, compatible with various iridium-based green phosphors, to realize highly efficient single-layer PhOLEDs of a maximum external quantum efficiency up to 8.3% (31.4 cd A-1) at a practical brightness of 1000 cd m-2 (8 V). © 2010 the Owner Societies.

Chang N.-N.,National Taiwan University | Shiao J.-C.,National Taiwan University | Gong G.-C.,National Taiwan Ocean University
Continental Shelf Research | Year: 2012

The environment of the East China Sea has been greatly impacted by both fishing and land-based pollution over the past decades, with a concomitant decline of fishery resources. Imposition of a seasonal fishing moratorium and a trawling prohibition zone has failed to engender recovery of fish communities. To help understand the respective impacts of environmental factors and fishing activities in the East China Sea ecosystem, fish samples and environmental parameters were collected in prohibited and open fishing areas, during the seasonal fishing moratorium. The inshore area of the East China Sea, corresponding to the prohibited zone for trawling, had extremely high nutrient concentrations and relatively low dissolved oxygen. The diversity index of demersal fish showed significantly negative correlations with nutrient concentrations and positive correlations with bottom-water dissolved oxygen. The inshore area of the East China Sea was heavily dominated by small-sized fishes, such as Gobiids. -Amblychaeturichthys hexanema and Apogonids. -Apogon lineatus, reflecting low survival of most fish species. In contrast, the offshore areas, with lower nutrient concentrations and higher dissolved oxygen, had higher biodiversity. These findings suggest that eutrophication and subsequent hypoxia is responsible for the limited recovery of fishery resources in the trawling prohibition area of the East China Sea. Therefore, a multi-pronged fishery management that involves both fishing restriction and environmental improvement is urgently needed in the East China Sea. © 2012 Elsevier Ltd.

Lee K.-L.,Academia Sinica, Taiwan | Chen P.-W.,National Taiwan Ocean University | Wu S.-H.,National Yang Ming University | Huang J.-B.,National Taiwan Ocean University | And 4 more authors.
ACS Nano | Year: 2012

Nanostructure-based sensors are capable of sensitive and label-free detection for biomedical applications. However, high-throughput and low-cost fabrication techniques are the main issues which should be addressed. In this study, chip-based nanostructures for intensity-sensitive detection were fabricated and tested using a thermal-annealing-assisted template-stripping method. Large-area uniform nanoslit arrays with a 500 nm period and various slit widths, from 30 to 165 nm, were made on plastic films. A transverse magnetic-polarized wave in these gold nanostructures generated sharp and asymmetric Fano resonances in transmission spectra. The full width at half-maximum bandwidth decreased with the decrease of the slit width. The narrowest bandwidth was smaller than 10 nm. Compared to nanoslit arrays on glass substrates using electron-beam lithography, the proposed chip has a higher intensity sensitivity up to 10367%/RIU (refractive index unit) and reaches a figure of merit up to 55. The higher intensity sensitivity for the template-stripped nanostructure is attributed to a smoother gold surface and larger grain sizes on the plastic film, which reduces the surface plasmon propagation loss. © 2012 American Chemical Society.

The Hsueh-Shan tunnel is the fifth longest road tunnel in the world. During the excavation, the tunnel encountered several events of groundwater inrush, causing serious delay of the construction. Data on groundwater discharge to the tunnel were gathered from the monitoring system and their spatial and temporal variations were analyzed. The results of the integrated analysis of groundwater discharge and local precipitation indicated that the discharge increased rapidly when the cumulative rainfall exceeded 85 mm. The groundwater level recession rate after a rainfall event was found to be independent of rainfall intensity. A hydrogeological conceptual model was developed to simulate the long-term groundwater discharge to the tunnel. Sensitivity analysis was first conducted to identify sensitive parameters, and then the calibration process was accomplished by the automated parameter estimation method. The calibrated model was then used to evaluate the potential impact of tunnel excavation on the Feitsui reservoir; the average percentage loss of inflow to the Feitsui reservoir from 2006 to 2010 is estimated to be 1. 74 %. The developed model can provide a tool for evaluating the regional hydrogeologic setting and the influence of tunnel construction on water resources. © 2012 Springer-Verlag.

Cheng S.-C.,National Taiwan Ocean University | Kuo C.-T.,National Kaohsiung First University of Science and Technology | Kuo C.-T.,Longcyuan Veterans Hospital | Wu D.-C.,National Kaohsiung First University of Science and Technology
Pattern Recognition | Year: 2010

This paper proposes a novel scheme for 3D model compression based on mesh segmentation using multiple principal plane analysis. This algorithm first performs a mesh segmentation scheme, based on fusion of the well-known k-means clustering and the proposed principal plane analysis to separate the input 3D mesh into a set of disjointed polygonal regions. The boundary indexing scheme for the whole object is created by assembling local regions. Finally, the current work proposes a triangle traversal scheme to encode the connectivity and geometry information simultaneously for every patch under the guidance of the boundary indexing scheme. Simulation results demonstrate that the proposed algorithm obtains good performance in terms of compression rate and reconstruction quality. © 2009 Elsevier Ltd. All rights reserved.

Eakin D.H.,University of Texas at Austin | McIntosh K.D.,University of Texas at Austin | Van Avendonk H.J.A.,University of Texas at Austin | Lavier L.,University of Texas at Austin | And 3 more authors.
Journal of Geophysical Research: Solid Earth | Year: 2014

We use offshore multichannel seismic (MCS) reflection and wide-angle seismic data sets to model the velocity structure of the incipient arc-continent collision along two trench perpendicular transects in the Bashi Strait between Taiwan and Luzon. This area represents a transition from a tectonic regime dominated by subduction of oceanic crust of the South China Sea, west of the Philippines, to one dominated by subduction and eventual collision of rifted Chinese continental crust with the Luzon volcanic arc culminating in the Taiwan orogeny. The new seismic velocity models show evidence for extended to hyperextended continental crust, ~10-15 km thick, subducting along the Manila trench at 20.5°N along transect T1, as well as evidence indicating that this thinned continental crust is being structurally underplated to the accretionary prism at 21.5°N along transect T2, but not along T1 to the south. Coincident MCS reflection imaging shows highly stretched and faulted crust west of the trench along both transects and what appears to be a midcrustal detachment along transect T2, a potential zone of weakness that may be exploited by accretionary processes during subduction. An additional seismic reflection transect south of T1 shows subduction of normal ocean crust at the Manila trench. ©2013. American Geophysical Union. All Rights Reserved.

Chen C.-J.,National Taiwan Ocean University | Chu T.-H.,National Taiwan University
IEEE Transactions on Microwave Theory and Techniques | Year: 2010

A 60-GHz substrate integrated waveguide Butler matrix designed based on a systematic approach is fabricated by a standard single-layer print circuit board process, which is more economical for mass production than are the advanced processes such as low-temperature co-fired ceramic, thick-film process, etc. The systematic approach involves design equations, simulations, and measurements. Starting with a set of explicit design equations for the short-slot couplers, one calculates the structure dimensions. The calculated dimensions are then optimized with full-wave simulation to finalize the design of the key components, including the couplers and phase shifters. With the use of a noncoaxial multiport measurement technique, the characteristics of the components are acquired through a probe station and a two-port vector network analyzer. Measurement technique plays a critical role in the systematic design approach. By measuring at the intrinsic ports or the wave ports defined in the full-wave simulations, the components are unambiguously verified and then integrated to complete the design of the Butler matrix. The resulting Butler matrix is also verified by the measured eight-port S-matrix, which is shown in good agreement with the simulated one. As the measured results of the Butler matrix show, for the operating bandwidth from 58 to 62 GHz, the reflections and isolations are lower than-13.5 dB and the insertion losses are below 2.5 dB. Much like the measured results of the components, the measured eight-port S-matrix not only verifies the design of the Butler matrix, but also will facilitate the follow-on design of a switched-beam antenna array. © 2010 IEEE.

Ku C.-Y.,National Taiwan Ocean University | Yeih W.,National Taiwan Ocean University | Liu C.-S.,National Taiwan University
International Journal of Nonlinear Sciences and Numerical Simulation | Year: 2010

In this paper, a scalar Newton-homotopy continuation method with the incorporation of a Manifold-Based Exponentially Convergent Algorithm (MBECA) for solving non-linear algebraic equations is proposed. To conduct a scalar-based homotopy continuation method, we first convert the vector function to a scalar function by taking the square norm of the vector function and then, by introducing a time variable T , a scalar Newton-homotopy function can be constructed. To improve the convergence and the accuracy of the scalar Newton-homotopy method, we use the scalar Newton-homotopy method to compute a rough solution and then use it as the initial guess for the MBECA. Taking the advantages of the global convergence from the scalar Newton-homotopy method and the characteristics of fast convergence from the MBECA, we expand the ability of the Newton-homotopy method to solve a large class of problems effectively and accurately. In addition, the proposed scalar Newton-homotopy method does not need to calculate the inverse of the Jacobian matrix and thus has great numerical stability. Results obtained show that the proposed method is highly efficient to find the true roots and it can also significantly improve the accuracy as well as the convergence. © Freund Publishing House Ltd.

Lin S.-M.,National Taiwan Ocean University | Nelson W.A.,NIWA - National Institute of Water and Atmospheric Research | Hommersand M.H.,University of North Carolina at Chapel Hill
Phycologia | Year: 2012

The alga known as Hymenena palmata f. marginata (Harvey) Kylin has been thought to be confined to the northern part of the South Island and the southern part of the North Island of New Zealand and is represented by a variety of thallus forms. The pattern of its apical growth is similar to that of Hymenena palmata (Harvey) Kylin, a poorly known species that is said to be widespread throughout New Zealand. As a consequence, H. palmata f. marginata has been misplaced under Hymenena for a long time. Unlike many species of Hymenena, the thallus branches entirely from the margins and lacks both macroscopic nerves and microscopic veins. Phylogenetic analysis of rbcL sequence data shows that, while H. palmata f. marginata is a member of the subfamily Phycodryoideae, it belongs in the Phycodryeae rather than the Cryptopleureae, a tribe that includes Hymenena, where it might otherwise be placed based on its gross morphology and growth by means of a marginal meristem with many obliquely dividing marginal cells. Procarp and cystocarp development are similar to that of the Phycodryeae, and the carposporangia are formed in chains rather than terminally as in Hymenena. The cystocarp of H. palmata f. marginata is unusual in that cells derived from the cystocarp floor form secondary pit connections with a large central fusion cell. We propose the name Hymenenopsis heterophylla S.-M. Lin, W.A. Nelson & Hommersand gen. et sp. nov. for this New Zealand red alga.

Huang S.-J.,National Taiwan University | Chang C.-L.,National Taiwan University | Wang P.-H.,National Taiwan University | Tsai M.-C.,National Taiwan University | And 2 more authors.
Journal of Experimental Botany | Year: 2013

Ethylene is an important plant hormone that regulates developmental processes in plants. The ethylene biosynthesis pathway is a highly regulated process at both the transcriptional and post-translational level. The transcriptional regulation of these ethylene biosynthesis genes is well known. However, post-translational modifications of the key ethylene biosynthesis enzyme 1-aminocyclopropane-1-carboxylate (ACC) synthase (ACS) are little understood. In vitro kinase assays were conducted on the type III ACS, AtACS7, fusion protein and peptides to determine whether the AtACS7 protein can be phosphorylated by calcium-dependent protein kinase (CDPK). AtACS7 was phosphorylated at Ser216, Thr296, and Ser299 by AtCDPK16 in vitro. To investigate further the function of the ACS7 gene in Arabidopsis, an acs7-1 loss-of-function mutant was isolated. The acs7-1 mutant exhibited less sensitivity to the inhibition of root gravitropism by treatment with the calcium chelator ethylene glycol tetraacetic acid (EGTA). Seedlings were treated with gradient concentrations of ACC. The results showed that a certain concentration of ethylene enhanced the gravity response. Moreover, the acs7-1 mutant was less sensitive to inhibition of the gravity response by treatment with the auxin polar transport inhibitor 1-naphthylphthalamic acid, but exogenous ACC application recovered root gravit-ropism. Altogether, the results indicate that AtACS7 is involved in root gravitropism in a calcium-dependent manner in Arabidopsis. © The Author 2013.

Lin K.Y.,National Taiwan University | Sastri A.R.,University of Quebec at Montréal | Gong G.C.,National Taiwan Ocean University | Gong G.C.,Taiwan Ocean Research Institute | Hsieh C.H.,National Taiwan University
Biogeosciences | Year: 2013

Zooplankton play an essential role in marine food webs, and understanding how community-level growth rates of zooplankton vary in the field is critical for predicting how marine ecosystem function may vary in the face of environmental changes. Here, we used the artificial cohort method to examine the effects of temperature, body size, and chlorophyll concentration (a proxy for food) on weight-specific growth rates for copepod communities in the East China Sea. Specifically, we tested the hypothesis that copepod community growth rates can be described by the metabolic theory of ecology (MTE), linking spatio-temporal variation of copepod growth rate with temperature and their body size. Our results generally agree with predictions made by the MTE and demonstrate that weight-specific growth rates of copepod communities in our study area are positively related with temperature and negatively related to body size. However, the regression coefficients of body size do not approach the theoretical predictions. Furthermore, we find that the deviation from the MTE predictions may be partly attributed to the effect of food availability (which is not explicitly accounted for by the MTE). In addition, significant difference in the coefficients of temperature and body size exists among taxonomic groups. Our results suggest that considering the effects of food limitation and taxonomy is necessary to better understand copepod growth rates under in situ conditions, and such effects on the MTE-based predictions need further investigation. © 2013 Author(s).

Wu S.-D.,National Taiwan Normal University | Wu C.-W.,National Taiwan Normal University | Lee K.-Y.,National Taiwan University | Lin S.-G.,National Taiwan Ocean University
Physica A: Statistical Mechanics and its Applications | Year: 2013

Multiscale entropy (MSE) is a prevalent algorithm used to measure the complexity of a time series. Because the coarse-graining procedure reduces the length of a time series, the conventional MSE algorithm applied to a short-term time series may yield an imprecise estimation of entropy or induce undefined entropy. To overcome this obstacle, the modified multiscale entropy (MMSE) was developed. The coarse-graining procedure was replaced with a moving-average procedure and a time delay was incorporated for constructing template vectors in calculating sample entropy. For conducting short-term time series analysis, this study shows that the MMSE algorithm is more reliable than the conventional MSE. © 2013 Elsevier B.V. All rights reserved.

Chen C.-J.,National Taiwan Ocean University | Chu T.-H.,National Taiwan University
Asia-Pacific Microwave Conference Proceedings, APMC | Year: 2011

S-matrix reconstruction transforms are based on two stages of matrix transformation to remove the mismatch-induced errors. Over the years, these transforms are widely used in measurements of multiport devices using two-port vector network analyzer, especially for noncoaxial applications because high-quality matched loads are hardly accessible. In this paper, analytical error analysis of the S-matrix reconstruction transforms is performed to show that three S-matrix transforms have the exact same accuracy. Additionally, the concept of acquiring stationary solutions is presented to improve the accuracy of reconstructing S-matrix with strongly reflecting auxiliary terminations. For noncoaxial measurements, strongly reflecting termination, such as a short-circuited or an open-circuited transmission line is more repeatable, reliable and economical than terminations with loss like resistors. Consequently, the use of strongly reflecting auxiliary terminations is speculated to ease noncoaxial multiport measurements. © 2011 Engineers Australia.

Wang S.-A.,National Taiwan University | Hung W.-Y.,National Taiwan Ocean University | Chen Y.-H.,National Taiwan Ocean University | Wong K.-T.,National Taiwan University
Organic Electronics: physics, materials, applications | Year: 2012

A new terfluorene hetero-analogue, 3TTP, introducing pyridinylthiophene as the conjugated constituent, exhibiting promising properties has been synthesized. The OLED device adopted 3TTP as emitting dopant incorporating its parent T3 as host displayed a sky-blue electroluminescence with a good performance (EQE = 3.9%). The blue device was further combined with rubrene gave a white OLED with a splendid EQE of 3.9% and high color purity [CIE = (0.31, 0.35)]. © 2012 Elsevier B.V. All rights reserved.

Lien C.-W.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University | Chang H.-T.,National Taiwan University
Chemical Communications | Year: 2012

Fibrinogen-modified bismuth-gold nanoparticles (Fib-Bi-Au NPs) are prepared and used as enzyme mimics for the H 2O 2-mediated reaction with Amplex Red (AR), which is further employed for determining thrombin activity and drug screening. © 2012 The Royal Society of Chemistry.

Lo S.-I.,National Taiwan University | Chen P.-C.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University | Chang H.-T.,National Taiwan University
Environmental Science and Technology | Year: 2012

We report a new adsorbent for removal of mercury species. By mixing Au nanoparticles (NPs) 13 nm in diameter with aluminum oxide (Al 2O 3) particles 50-200 μm in diameter, Au NP-Al 2O 3 adsorbents are easily prepared. Three adsorbents, Al 2O 3, Au NPs, and Au NP-Al 2O 3, were tested for removal of mercury species [Hg 2+, methylmercury (MeHg +), ethylmercury (EtHg +), and phenylmercury (PhHg +)]. The Au NP adsorbent has a higher binding affinity (dissociation constant; K d = 0.3 nM) for Hg 2+ ions than the Al 2O 3 adsorbent (K d = 52.9 nM). The Au NP-Al 2O 3 adsorbent has a higher affinity for mercury species and other tested metal ions than the Al 2O 3 and Au NP adsorbents. The Au NP-Al 2O 3 adsorbent provides a synergic effect and, thus, is effective for removal of most tested metal ions and organic mercury species. After preconcentration of mercury ions by an Au NP-Al 2O 3 adsorbent, analysis of mercury ions down to the subppq level in aqueous solution was performed by inductively coupled plasma mass spectrometry (ICP-MS). The Au NP-Al 2O 3 adsorbent allows effective removal of mercury species spiked in lake water, groundwater, and seawater with efficiencies greater than 97%. We also used Al 2O 3 and Au NP-Al 2O 3 adsorbents sequentially for selectively removing Hg 2+ and MeHg + ions from water. The low-cost, effective, and stable Au NP-Al 2O 3 adsorbent shows great potential for economical removal of various mercury species. © 2012 American Chemical Society.

Huang C.-Y.,National Taiwan Ocean University | Hsu C.-H.,National Tsing Hua University | Chang Y.-C.,Academia Sinica, Taiwan | Chang Y.-C.,National Taiwan University | Chen K.-T.,Academia Sinica, Taiwan
Proceedings of the 4th ACM Multimedia Systems Conference, MMSys 2013 | Year: 2013

Cloud gaming is a promising application of the rapidly expanding cloud computing infrastructure. Existing cloud gaming systems, however, are closed-source with proprietary protocols, which raises the bars to setting up testbeds for experiencing cloud games. In this paper, we present a complete cloud gaming system, called GamingAnywhere, which is to the best of our knowledge the first open cloud gaming system. In addition to its openness, we design GamingAnywhere for high extensibility, portability, and reconfigurability. We implement GamingAnywhere on Windows, Linux, and OS X, while its client can be readily ported to other OS's, including iOS and Android. We conduct extensive experiments to evaluate the performance of GamingAnywhere, and compare it against two well-known cloud gaming systems: OnLive and StreamMyGame. Our experimental results indicate that GamingAnywhere is efficient and provides high responsiveness and video quality. For example, GamingAnywhere yields a per-frame processing delay of 34 ms, which is 3+ and 10+ times shorter than OnLive and StreamMyGame, respectively. Our experiments also reveal that all these performance gains are achieved without the expense of higher network loads. The proposed GamingAnywhere can be employed for setting up cloud gaming testbeds, which, we believe, will stimulate more research innovations on cloud gaming systems. © 2013 ACM.

Chen J.-T.,National Taiwan Ocean University | Han H.,Tsinghua University | Kuo S.-R.,National Taiwan Ocean University | Kao S.-K.,National Taiwan Ocean University
Inverse Problems in Science and Engineering | Year: 2014

The occurring mechanism of the ill-conditioned system due to degenerate scale in the direct boundary element method (BEM) and the indirect BEM is analytically examined by using degenerate kernels. Five regularization techniques to ensure the unique solution, namely hypersingular formulation, method of adding a rigid body mode, rank promotion by adding the boundary flux equilibrium (direct BEM), CHEEF method and the Fichera's method (indirect BEM), are analytically studied and numerically implemented. In this paper, we examine the sufficient and necessary condition of boundary integral formulation for the uniqueness solution of 2D Laplace problem subject to the Dirichlet boundary condition. Both analytical study and BEM implementation are addressed. For the analytical study, we employ the degenerate kernel in the polar and elliptic coordinates to derive the unique solution by using five regularization techniques for any size of circle and ellipse, respectively. Full rank of the influence matrix in the BEM using Fichera's method for both ordinary scale and degenerate scale is also analytically proved. In numerical implementation, the BEM programme developed by NTOU/MSV group is employed to see the validity of the above formulation. Finally, the circular and elliptic cases are numerically demonstrated by using five regularization techniques. Besides, a general shape of a regular triangle is numerically implemented to check the uniqueness solution of BEM. © 2014 © 2014 Taylor & Francis.

Chen C.-K.,National Taiwan University | Shiang Y.-C.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University | Chang H.-T.,National Taiwan University
Biosensors and Bioelectronics | Year: 2011

We have developed a colorimetric probe, based on the aggregation of gold nanoparticles (Au NPs), for the detection of DNA and for the analysis of single-nucleotide polymorphism (SNP); this probe functions through the modulation of the activity of thrombin (Thr) in the presence of bivalent thrombin-binding aptamers (TBAs). The bivalent TBAs were formed from TBA27' (comprising a 27-base sequence providing TBA27 functionality, a T5 linker, and an 11-base sequence for hybridization) and TBA15' (comprising a 15-base sequence providing TBA15 functionality, a T5 linker, and a 12-base sequence for hybridization) through their hybridization with perfectly matched DNA (DNApm). The bivalent TBAs interacted specifically with thrombin, suppressing its activity toward fibrinogen-modified Au NPs (Fib-Au NPs). The potency of the inhibitory effect of TBA15'-TBA27'/DNApm toward thrombin - and, thus, the degree of aggregation of the Fib-Au NPs - was highly dependent on the concentration of DNApm. Under the optimal conditions (50pM thrombin, 2nM TBA15', 2nM TBA27', and 38pM Fib-Au NPs), the linear relationship of the response of the probe toward DNApm extended from 0.1 to 2nM, with a correlation coefficient of 0.97. The limit of detection (LOD) for DNApm was 20pM, based on a signal-to-noise ratio of 3. We also applied a corresponding TBA15″-TBA27″/Thr/Fib-Au NP probe to the detection of the SNP of the Arg249Ser unit in the TP53 gene, with an LOD of 32pM. Relative to conventional molecular beacon-based and crosslinking aggregation-based Au NP probes, our new approach offers higher sensitivity and higher selectivity toward DNA. © 2011 Elsevier B.V.

Huang H.-L.,National Taiwan Ocean University | Chou C.F.,National Taiwan Ocean University | Shiao S.H.,National Taiwan Ocean University | Liu Y.-C.,National Taiwan Ocean University | And 4 more authors.
Optics Express | Year: 2013

It is demonstrated that photoluminescence of DCJTB can be enhanced by surface plasmons occurred in silver nanoparticle arrays on glass substrates fabricated by using nanosphere lithography (NSL) combined with reactive ion etching (RIE). By changing the size of the seed polystyrene nanosphere with fixed thickness of SiO2 film as a buffer layer between silver nanoparticles and fluorescent dye, we systematically studied the interaction between surface plasmons in Ag nanostructures and fluorescent dye by measuring the photoluminescence and time-resolved photoluminescence (TRPL) of the samples. As compared with pure DCJTB, it is observed that PL enhancement as high as 9.4 times and life time shortening from 0.966 ns shortened to 0.63 ns can be achieved with polystyrene nanosphere 430nm in diameter. The physical origin due to plasmonic excitation has been clarified from 3D finite element simulations, as well as the assistance of UV-visible reflectance spectrum. © 2013 Optical Society of America.

Chu J.P.,National Taiwan University of Science and Technology | Lee C.M.,National Taiwan University of Science and Technology | Huang R.T.,National Taiwan Ocean University | Liaw P.K.,University of Tennessee at Knoxville
Surface and Coatings Technology | Year: 2011

With a 200-nm-thick Zr53Cu29Al12Ni6 glass-forming film, the four-point-bending fatigue life of a 316L stainless-steel substrate is improved from 4.4×105 cycles for the uncoated sample by ~10 times to 4.5×106 cycles at a stress level of 750MPa. The fatigue life is further improved by more than 22 times to >107 cycles when the film is annealed in the supercooled liquid region. The excellent mechanical properties of the thin film, specifically high strength and improved ductility, coupled with the good film adhesion to the substrate as well as the improved surface roughness, are the key factors that improve the fatigue resistance of the coated materials. © 2011 Elsevier B.V.

Wang P.-J.,Ming Chi University of Technology | Li C.-M.,National Taiwan Ocean University | Wu C.-Y.,National Taiwan Ocean University | Li H.-J.,National Taiwan University
IEEE Transactions on Intelligent Transportation Systems | Year: 2010

State-of-the-art traffic-flow-detection technology includes the use of a looped vehicle detector, an infrared detector, an image detector, and a microwave detector. However, there are limitations that are associated with each detector. In this paper, we propose a channel awareness vehicle detector that can overcome these limitations. It employs only one pair of transmitterreceiver antennas to simultaneously perform the multilane and multivehicle identifications. By using the characteristics of channel variations, the proposed vehicle detector can determine the vehicle location, speed, and type. Our measurement results demonstrate its capabilities. © 2010 IEEE.

Li C.-L.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University | Chen W.-H.,Institute of Nuclear Energy Research of Taiwan | Chiang C.-K.,National Taiwan University | Chang H.-T.,National Taiwan University
Analyst | Year: 2012

Oligonucleotide (T30695) modified gold nanoparticles (T30695-Au NPs) have been prepared and employed for quantification of lead ions (Pb2+) in blood. The detection of Pb2+ ions is through the formation of Au-Pb alloys and oligonucleotide-Pb2+ complexes that catalyze the H 2O2-mediated oxidation of non-fluorescent Amplex UltraRed (AUR) to form a highly fluorescent oxidized AUR product. Surface-assisted laser desorption/ionization time-of-flight mass spectrometry (SALDI-TOF MS) and inductively coupled plasma mass spectrometry (ICP-MS) revealed the formation of Au-Pb alloys on the surfaces of the 40T30695-Au NPs (i.e., the system featuring 40 molecules of T30695 per Au NP) in the presence of Pb2+ ions, leading to increased catalytic activity for the H2O 2-mediated oxidation of AUR. The fluorescence intensity (excitation/emission maxima: ca. 540/584 nm) of the oxidized AUR product is proportional to the concentration of Pb2+ ions over the range 0.1-100 nM, with a linear correlation (R2 = 0.99). The 40T30695-Au NP/AUR probe is highly selective toward Pb2+ ions (by at least 200-fold over other tested metal ions). The 40T30695-Au NPs/AUR probe provided limits of detection (LOD, at a signal-to-noise ratio 3) for Pb2+ ions of 0.05 and 0.1 nM, in Tris-acetate solution (5 mM, pH 8.0) without and with salt (150 mM NaCl, 5 mM KCl, 1 mM MgCl2, and 1 mM CaCl2), respectively. Without conducting tedious sample pretreatment, the approach allows detection of Pb2+ ions in blood samples, showing the potential of the 40T30695-Au NPs/AUR assay for on-site and real-time detection of Pb 2+ ions in biological samples. This journal is © 2012 The Royal Society of Chemistry.

Liu C.-S.,National Taiwan University | Kuo C.-L.,National Taiwan Ocean University
CMES - Computer Modeling in Engineering and Sciences | Year: 2011

The Tikhonov method is a famous technique for regularizing ill-posed systems. In this theory a regularization parameter a needs to be determined. Basedon an invariant-manifold defined in the space of (x; t) and from the Tikhonov minimization functional, we can derive an optimal vector driven system of nonlinear ordinary differential equations (ODEs). In the Optimal Vector Driven Algorithm (OVDA), the optimal regularization parameter αk is presented in the iterative solution of x, which means that a dynamical Tikhonov regularization method is involved in the solution of nonlinear ill-posed problem. The OVDA is an extension of the Landweber-Scherzer iterative algorithm. Numerical examples of nonlinear ill-posed systems under noise are examined, revealing that the present OVDA has a good computational efficiency and accuracy. Copyright © 2011 Tech Science Press.

Ku C.-Y.,National Taiwan Ocean University | Yeih W.,National Taiwan Ocean University | Liu C.-S.,National Taiwan University
CMES - Computer Modeling in Engineering and Sciences | Year: 2011

In this paper, a general dynamical method based on the construction of a scalar homotopy function to transform a vector function of Non-Linear Algebraic Equations (NAEs) into a time-dependent scalar function by introducing a fictitious time-like variable is proposed. With the introduction of a transformation matrix, the proposed general dynamical method can be transformed into several dynamical Newton-like methods including the Dynamical Newton Method (DNM), the Dynamical Jacobian-Inverse Free Method (DJIFM), and the Manifold-Based Exponentially Convergent Algorithm (MBECA). From the general dynamical method, we can also derive the conventional Newton method using a certain fictitious timelike function. The formulation presented in this paper demonstrates a variety of flexibility with the use of different transformation matrices to create other possible dynamical methods for solving NAEs. These three dynamical Newton-like methods are then adopted for the solution of ill-conditioned systems of nonlinear equations and applied to boundary value problems. Results reveal that taking advantages of the general dynamical method the proposed three dynamical Newton-like methods can improve the convergence and increase the numerical stability for solving NAEs, especially for the system of nonlinear problems involving ill-conditioned Jacobian or poor initial values which cause convergence problems. Copyright © 2011 Tech Science Press.

Hung W.-Y.,National Taiwan Ocean University | Fang G.-C.,National Taiwan Ocean University | Chang Y.-C.,National Taiwan University | Kuo T.-Y.,National Taiwan University | And 4 more authors.
ACS Applied Materials and Interfaces | Year: 2013

A simple three-layer interfacial-type yellow emission exciplex device with an external quantum efficiency as high as 7.7% has been successfully achieved by combining conformation compatible C3-symmetric hole-transporting TCTA and electron-transporting 3P-T2T. The excellent and balanced charge-transporting properties of TCTA and 3P-T2T and the large energy-levels offset (0.8 eV) of TCTA/3P-T2T interface play important roles for the efficient exciplexes formation, which are effectively confined around the interfacial region due to the high triplet energies (2.85 eV) of TCTA and 3P-T2T. The high-performance OLED was believed to be from the effective harvest of exciplex triplet excitons via reverse intersystem crossing process. © 2013 American Chemical Society.

Wu S.-D.,National Taiwan Normal University | Wu C.-W.,National Taiwan Normal University | Lin S.-G.,National Taiwan Ocean University | Wang C.-C.,Industrial Technology Research Institute of Taiwan | Lee K.-Y.,National Taiwan University
Entropy | Year: 2013

Multiscale entropy (MSE) was recently developed to evaluate the complexity of time series over different time scales. Although the MSE algorithm has been successfully applied in a number of different fields, it encounters a problem in that the statistical reliability of the sample entropy (SampEn) of a coarse-grained series is reduced as a time scale factor is increased. Therefore, in this paper, the concept of a composite multiscale entropy (CMSE) is introduced to overcome this difficulty. Simulation results on both white noise and 1/f noise show that the CMSE provides higher entropy reliablity than the MSE approach for large time scale factors. On real data analysis, both the MSE and CMSE are applied to extract features from fault bearing vibration signals. Experimental results demonstrate that the proposed CMSE-based feature extractor provides higher separability than the MSE-based feature extractor. © 2013 by the authors; licensee MDPI, Basel, Switzerland.

Chen L.-Y.,National Taiwan University | Ou C.-M.,National Taiwan University | Chen W.-Y.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University | Chang H.-T.,National Taiwan University
ACS Applied Materials and Interfaces | Year: 2013

Poly(N-isopropylacrylamide) microgels (PNIPAM MGs) incorporated with photoluminescent gold nanodots (Au NDs) have been prepared and employed for the detection of mercury ions (Hg2+). Each of the PNIPAM MGs (hydrodynamic diameter 615 ± 15 nm) contains several Au NDs (diameter 1.8 ± 0.2 nm) in the Au ND-PNIPAM MGs. Like Au NDs, Au ND-PNIPAM MGs exhibit an absorption band at 375 nm that is assigned for ligand to metal charge transfer mixed with metal centered (ds/dp) states and photoluminescence at 520 nm originated from Au ND/polynuclear gold(I)-thiolate (core/shell) complexes. Purification of Au ND-PNIPAM MGs relative to Au NDs is much easier through a simple centrifugation/wash process. On the basis of Hg2+-induced photoluminescence quenching due to the formation of Au-Hg amalgam and formation of Au ND-PNIPAM MGs aggregates, the signal response of Au ND-PNIPAM MGs against Hg2+ concentration is linear over a range from 2 to 20 nM (r = 0.9945). This selective approach provides limits of detection for Hg 2+ (at a signal-to-noise ratio of 3) of 1.9 and 1.7 nM in phosphate buffer solutions (5 mM, pH 7.0) with and without containing 500 mM NaCl, respectively. This selective and sensitive Au ND-PNIPAM MG probe has been applied to the determination of the concentration of Hg in a representative fish sample, showing its practical potential for monitoring of Hg levels in complicated biological and environmental samples. © 2013 American Chemical Society.

Shiang Y.-C.,National Taiwan University | Ou C.-M.,National Taiwan University | Chen S.-J.,National Taiwan University | Ou T.-Y.,National Taiwan Ocean University | And 3 more authors.
Nanoscale | Year: 2013

We have developed aptamer (Apt)-conjugated gold nanoparticles (Apt-Au NPs, 13 nm in diameter) as highly effective inhibitors for human immunodeficiency virus type 1 reverse transcriptase (HIV-1 RT). Two Apts, RT1t49 (Apt pol) and ODN 93 (AptRH), which recognize the polymerase and RNase H regions of HIV-1 RT, are used to conjugate Au NPs to prepare Aptpol-Au NPs and AptRH-Au NPs, respectively. In addition to DNA sequence, the surface density of the aptamers on Au NPs (nApt-Au NPs; n is the number of aptamer molecules on each Au NP) and the linker length number (Tm; m is the base number of the deoxythymidine linker) between the aptamer and Au NPs play important roles in determining their inhibition activity. A HIV-lentiviral vector-based antiviral assay has been applied to determine the inhibitory effect of aptamers or Apt-Au NPs on the early stages of their replication cycle. The nuclease-stable G-quadruplex structure of 40AptRH-T45-Au NPs shows inhibitory efficiency in the retroviral replication cycle with a decreasing infectivity (40.2%). © The Royal Society of Chemistry 2013.

Chen L.-Y.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University | Chen W.-Y.,National Taiwan University | Lin H.-J.,National Taiwan Ocean University | Chang H.-T.,National Taiwan University
Biosensors and Bioelectronics | Year: 2013

In this study we used photoluminescent 11-mercaptoundecanoic acid-bound gold nanodots (11-MUA-Au NDs) to detect hemoglobin through photoluminescence (PL) quenching. The mechanism of quenching, which occurred through redox reactions between the 11-MUA-Au NDs and the Fe(II) atoms of hemin units, was supported by an increase in the signals (G 2.0 and 5.9) of high-spin state Fe(III) ions. The Stern-Volmer quenching constants (Ksv) for hemin, cytochrome c, hemoglobin, and myoglobin were 5.6×107, 1.7×107, 1.6×107, and 6.2×106M-1, respectively, in good agreement with the order of their reduction potentials. When excited at 375nm, the PL intensity of the 11-MUA-Au NDs at 520nm decreased upon increasing the concentration of hemoglobin from 1.0 to 10nM (R2=0.9913). This approach using bovine serum albumin blocked 11-MUA-Au NDs provided a limit of detection for hemoglobin (at a signal-to-noise ratio of 3) of 0.5nM in biological buffer, with great selectivity over other non-heme-containing proteins, including human serum albumin, Β-casein, and carbonic anhydrase. We validated the practicality of this approach through the determination of the concentrations (1.85-2.46mM) of hemoglobin in diluted (106-fold) human blood samples based on PL quenching of Au NDs. This simple, sensitive, and selective approach holds great potential for the diagnosis of several diseases, including anemia, erythrocytosis, and thalassemias. © 2012 Elsevier B.V.

Liu Y.-C.,National Taiwan Ocean University | Chiang C.-K.,National Taiwan University | Chang H.-T.,National Taiwan University | Lee Y.-F.,National Taiwan Ocean University | Huang C.-C.,National Taiwan Ocean University
Advanced Functional Materials | Year: 2011

In this paper, a matrix-free strategy based on the analysis of nitrocellulose membranes (NCMs) modified with gold nanoparticles (AuNPs) is described, using pulsed-laser desorption ionization mass spectrometry (LDI-MS) for comprehensive quantification of lead ions (Pb) with a sub-nanomolar sensitivity in complicated biofluids. The strong hydrophobic interactions between the NCM and bovine serum albumin (BSA) lead to trapping of BSA-modified AuNPs (BSA-AuNPs), resulting in the formation of a nanocomposite film of BSA-AuNPs on the membrane (BSA-AuNP/NCM). When the AuNPs interact with thiosulfate (S2O3 2-) ions in solution, Au +·S2O3 2- complexes form on the AuNP surfaces, facilitating the deposition of Pb atoms in the form of PbAu alloys in the presence of Pb2+ ions. The BSA-AuNP/NCM nanocomposite is a useful LDI-MS matrix because it allows: i) the soft and enhanced ionization of Pb-Au alloys from the AuNP surfaces; ii) accurate mass measurements (precision: 5 ppm) of Au, Pb, and Au-Pb ions; iii) the extraction of Pb 2+ ions from very-dilute aqueous solutions (1.0 × 10 -9 M); and iv) analyses to be performed directly after the introduction of the substrate into the mass-analysis LDI spectrometer (i.e., without the need for an elution process). In contrast to the noisy spectra typically obtained when using other AuNP-assisted LDI approaches, our homogeneous BSA-AuNP/NCM nanocomposite provides clean mass spectra with fewer and weaker signals from AuNP-associated interfering species. As a result, the BSA-AuNP/NCM substrates allow sensitive LDI-MS detection of analytes with low mass-to-charge ratios. Under optimal conditions, this LDI-MS approach provides high sensitivity, a wide dynamic detection range (1.0 × 10 -9-5.0 × 10-6 M), and a high selectivity toward Pb2+ ions (with at least a 100-fold concentration tolerance relative to other metal ions). The BSA-AuNP/NCM nanocomposite also provides excellent shot-to-shot (<5%) and sample-to-sample (<5%) reproducibilities of ion production because of its homogeneous substrate surface, thereby enabling LDI-based measurements to a consistent quantification of Pb2+ ions in real samples (e.g., urine, whole blood). © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hung W.-Y.,National Taiwan Ocean University | Chen Z.-W.,National Taiwan Ocean University | You H.-W.,National Taiwan Ocean University | Fan F.-C.,National Taiwan University | And 2 more authors.
Organic Electronics: physics, materials, applications | Year: 2011

In this study we used a known host material diphenylbis[4-(9-carbazoyl) phenyl]silane (SiCa) to realize a highly efficient bis[4,6-(difluorophenyl)- pyridinato-N,C2′]picolinate (FIrpic)-based blue phosphorescent device exhibiting high efficiencies of up to 18.3%, 41.5 cd/A, and 31 lm/W in a carrier- and exciton-confined device structure. At a practical brightness of 1000 cd/m2, the device performance (ηext) remained as high as 16.7%. The enhanced efficiency and reduced roll-off resulted mainly from the introduction of (a) DTAF as an HTL that efficiently blocked and confined excitons within the FIrpic-doped emissive layer, and (b) a thin layer of DPPS between the EML and TAZ, serving as an exciton- and hole-blocking layer to suppress exciton quenching by FIrpic at the EML-ETL interface. In addition, we incorporated a red phosphorescent dopant (Mpq2Iracac) into the blue device to fabricate a white phosphorescent organic light-emitting device, which exhibited satisfactory efficiencies (11.6%, 21.2 cd/A, 14.2 lm/W) with the Commission Internationale de L'éclairage (CIE) coordinates of (0.35, 0.38). © 2011 Elsevier B.V. All rights reserved.

Chen Y.-W.,National Taiwan Ocean University | Yeih W.-C.,National Taiwan Ocean University | Liu C.-S.,National Taiwan University | Chang J.-R.,National Taiwan Ocean University
Engineering Analysis with Boundary Elements | Year: 2012

Here, we develop a multi-scaling Trefftz method (MSTM) for the Laplace equation associated with the group-preserving scheme (GPS) to describe nonlinear sloshing behavior of the incompressible, non-viscous, and irrotational fluid. Chen et al. [29] proposed that the characteristic length of the Trefftz method and the concept of controlled volume could be used to overcome numerical errors and dissipation in the simulation of the sloshing problem. However, the nonlinear dependence of the characteristic length on initial conditions was neglected in the numerical development. In addition, this study presents a numerical method with automatically adaptive computational steps for describing the nonlinear sloshing behavior as well as for satisfying the conservation of mass at each time step. The method developed here presents a simple and stable way to cope with the nonlinear sloshing problem. © 2011 Elsevier Ltd.

Chen W.-L.,National Taiwan University | Wang G.-S.,National Taiwan University | Gwo J.-C.,National Taiwan Ocean University | Chen C.-Y.,National Taiwan University
Talanta | Year: 2012

This study developed and validated a method of measuring the feminizing chemicals 4-tert-octylphenol, 4-nonylphenol, nonylphenol monoethoxycarboxylate (NP 1EC), nonylphenol monoethoxylate (NP 1EO), nonylphenol diethoxylate (NP 2EO), estrone, 17β-estradiol, estriol, 17α-ethinyl estradiol and bisphenol A in river water, sediment, and tissue using ultra-high performance liquid chromatography/tandem mass spectrometry (UHPLC/MS/MS) and isotope-dilution techniques. Water samples were pretreated using disk-type automated solid-phase extraction (SPE). Solid samples of sediment, fish, and clams were treated with matrix solid-phase dispersion (MSPD) using C 8 adsorbent. Eluents were directly passed following alumina cartridges for cleanup. The signal intensity of analytes on electrospray ionization (ESI) was compared with that of atmospheric pressure photoionization (APPI). The analytes were separated on a UHPLC C 18 column with aqueous 10-mM ammonium acetate for NPEOs and aqueous 10-mM N-methylmorpholine for the other compounds. On-line cleanup was evaluated using two-dimensional liquid chromatography (2-D LC). ESI could provide satisfactory response for all of the analytes. Though APPI did not offer suitable response for NP 1EO, NP 2EO and NP 1EC, it provided better signal intensities for the steroid estrogens (1.0-2.4 times) and the phenols (3.2-4.4 times) than ESI. UHPLC shortened chromatographic time to less than 10 min. Disk-type automated SPE and MSPD dramatically increased the throughput of sample preparation. The extraction efficiency on surface water samples ranged from 10% to 91%. The extraction efficiency of MSPD on sediment, fish, and clams was 51-101%, 36-109%, and 30-111%, respectively. Acidic alumina cleanup was essential for the analysis of the tissue sample, and reduced matrix effects better than 2-D LC on-line cleanup. The limits of detection (LODs) in water ranged from 0.81 ng/L to 89.9 ng/L. The LODs in sediment and tissue ranged from tens of pg/g wet weight to only a few ng/g wet weight. This method proved to be accurate and reproducible, as both quantitative biases and relative deviations remained smaller than 20% at three spiked levels. © 2011 Elsevier B.V. All rights reserved.

Tsai S.-W.,Chang Gung University | Liou H.-M.,National Taiwan Ocean University | Lin C.-J.,Chang Gung University | Kuo K.-L.,National Taiwan Ocean University | And 4 more authors.
PLoS ONE | Year: 2012

Electrospinning is a simple and efficient method of fabricating a non-woven polymeric nanofiber matrix. However, using fluorinated alcohols as a solvent for the electrospinning of proteins often results in protein denaturation. TEM and circular dichroism analysis indicated a massive loss of triple-helical collagen from an electrospun collagen (EC) matrix, and the random coils were similar to those found in gelatin. Nevertheless, from mechanical testing we found the Young's modulus and ultimate tensile stresses of EC matrices were significantly higher than electrospun gelatin (EG) matrices because matrix stiffness can affect many cell behaviors such as cell adhesion, proliferation and differentiation. We hypothesize that the difference of matrix stiffness between EC and EG will affect intracellular signaling through the mechano-transducers Rho kinase (ROCK) and focal adhesion kinase (FAK) and subsequently regulates the osteogenic phenotype of MG63 osteoblast-like cells. From the results, we found there was no significant difference between the EC and EG matrices with respect to either cell attachment or proliferation rate. However, the gene expression levels of OPN, type I collagen, ALP, and OCN were significantly higher in MG63 osteoblast-like cells grown on the EC than in those grown on the EG. In addition, the phosphorylation levels of Y397-FAK, ERK1/2, BSP, and OPN proteins, as well as ALP activity, were also higher on the EC than on the EG. We further inhibited ROCK activation with Y27632 during differentiation to investigate its effects on matrix-mediated osteogenic differentiation. Results showed the extent of mineralization was decreased with inhibition after induction. Moreover, there is no significant difference between EC and EG. From the results of the protein levels of phosphorylated Y397-FAK, ERK1/2, BSP and OPN, ALP activity and mineral deposition, we speculate that the mechanism that influences the osteogenic differentiation of MG63 osteoblast-like cells on EC and EG is matrix stiffness and via ROCK-FAK-ERK1/2. © 2012 Tsai et al.

Liu Y.-C.,National Taiwan Ocean University | Chang H.-T.,National Taiwan University | Chiang C.-K.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University
ACS Applied Materials and Interfaces | Year: 2012

In this paper, we describe a pulsed-laser desorption/ionization mass spectrometry (LDI-MS) approach for the detection of proteins with femtomolar sensitivity through the analysis of gold (Au) clusters desorbed from aptamer-modified gold nanoparticles (Apt-AuNPs) on a nitrocellulose membrane (NCM). After the target protein (thrombin) was selectively captured by the surface-bound 29-mer thrombin-binding aptamer (TBA 29), the thrombin/TBA 29-AuNP complexes were concentrated and deposited onto the NCM to form a highly efficient background-free surface-assisted LDI substrate. Under pulsed laser irradiation (355 nm), the binding of thrombin decreased the desorption and/or ionization efficiencies of the Au atoms from the AuNP surfaces. The resulting decreases in the intensities of the signals for Au clusters in the mass spectra provided a highly amplified target-labeling indicator for the targeted protein. Under optimized conditions, this probe was highly sensitive (limit of detection: ca. 50 fM) and selective (by at least 1000-fold over other proteins) toward thrombin; it also improved reproducibility (<5%) of ion production by presenting a more-homogeneous substrate surface, thereby enabling LDI-based measurements for the accurate and precise quantification of thrombin in human serum. This novel LDI-MS approach allows high-speed analyses of low-abundance thrombin with ultrahigh sensitivity; decorating the AuNP surfaces with other aptamers also allowed amplification of other biological signals. © 2012 American Chemical Society.

Chen I.L.,National Kaohsiung Marine University | Lee J.W.,National Taiwan Ocean University | Hsiao Y.C.,National Taiwan University | Chen J.T.,National Taiwan Ocean University
Engineering Analysis with Boundary Elements | Year: 2012

Scattering problems of water waves impinging on bottom-mounted vertical cylinders are solved by using the dual boundary element method (DBEM). Both resonances due to near-trapped mode (physics) and fictitious frequency (mathematics) are examined. It is found that the near-trapped mode is a physical phenomenon and the fictitious frequency stems from the numerical instability. A trapped mode is associated with a singularity that lies on the real axis of complex wave number. A near-trapped mode means a localized behavior that energy is trapped in a truncated periodical structure. Critical wave number for the near-trapped mode and fictitious frequency of numerical instability are detected in this work. Numerical oscillation of the resultant force near the fictitious frequency is also observed by using the DBEM. Fictitious frequencies depend on the formulation instead of the specified boundary condition. Both the Burton and Miller approach and the CHIEF method are employed to alleviate the problem of irregular frequencies. Highly rank-deficiency matrices for four identical cylinders are numerically examined and the rank is promoted by adding valid CHIEF constraints. Parameter study of spacing and radius of cylinders on the near-trapped mode and fictitious frequency is also addressed. Several examples of water wave interaction by circular and square cylinders are demonstrated to see the validity of the present formulation. © 2012 Elsevier Ltd. All rights reserved.

Yang W.-C.,Academia Sinica, Taiwan | Yang W.-C.,University of Taipei | Yang W.-C.,National Chung Hsing University | Yang W.-C.,National Taiwan University | Yang W.-C.,National Taiwan Ocean University
Evidence-based Complementary and Alternative Medicine | Year: 2014

Bidens pilosa L. is an easy-to-grow, widespread, and palatable perennial on earth. Hence, it has traditionally been used as foods and medicines without noticeable adverse effects. Despite significant advancement in chemical and biological studies of B. pilosa over the past few years, comprehensive and critical reviews on its anti-diabetic properties are missing. The present review is to summarize up-to-date information on the pharmacology, phytochemistry, and toxicology of B. pilosa, in regard to type 1 diabetes and type 2 diabetes from the literature. In addition to botanical studies and records of the traditional use of B. pilosa in diabetes, scientific studies investigating antidiabetic action of this species and its active phytochemicals are presented and discussed. The structure and biosynthesis of B. pilosa and its polyynes in relation to their anti-diabetic action and mechanism are emphasized. Although some progress has been made, rigorous efforts are further required to unlock the molecular basis and structure-activity relationship of the polyynes isolated from B. pilosa before their clinical applications. The present review provides preliminary information and gives guidance for further anti-diabetic research and development of this plant. © 2014 Wen-Chin Yang.

Lan G.-Y.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University | Chang H.-T.,National Taiwan University
Chemical Communications | Year: 2010

Fluorescent DNA-Ag NCs are demonstrated as novel, label-free, and turn-on fluorescence probes for Cu2+ ions sensors. We also used this novel fluorescent probe to determine Cu2+ ions in Montana soil (SRM 2710) and pond water. © 2010 The Royal Society of Chemistry.

Lin T.-E.,National Taiwan University | Chen W.-H.,Institute of Nuclear Energy Research of Taiwan | Shiang Y.-C.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University | Chang H.-T.,National Taiwan University
Biosensors and Bioelectronics | Year: 2011

We have developed a colorimetric assay-using aptamer modified 13-nm gold nanoparticles (Apt-Au NPs) and fibrinogen adsorbed Au NPs (Fib-Au NPs, 56nm)-for the highly selective and sensitive detection of platelet-derived growth factors (PDGF). Apt-Au NPs and Fib-Au NPs act as recognition and reporting units, respectively. PDGF-binding-aptamer (Apt PDGF) and 29-base-long thrombin-binding-aptamer (Apt thr29) are conjugated with Au NPs to prepare functional Apt-Au NPs (Apt PDGF/Apt thr29-Au NPs) for specific interaction with PDGF and thrombin, respectively. Thrombin interacts with Fib-Au NPs in solutions to catalyze the formation of insoluble fibrillar fibrin-Au NPs agglutinates through the polymerization of the unconjugated and conjugated fibrinogen. The activity of thrombin is suppressed once it interacts with the Apt PDGF/Apt thr29-Au NPs. The suppression decreases due to steric effects through the specific interaction of PDGF with Apt PDGF, occurring on the surfaces of Apt PDGF/Apt thr29-Au NPs. Under optimal conditions [Apt PDGF/Apt thr29-Au NPs (25pM), thrombin (400pM) and Fib-Au NPs (30pM)], the Apt PDGF/Apt thr29-Au NPs/Fib-Au NPs probe responds linearly to PDGF over the concentration range of 0.5-20nM with a correlation coefficient of 0.96. The limit of detection (LOD, signal-to-noise ratio=3) for each of the three PDGF isoforms is 0.3nM in the presence of bovine serum albumin at 100μM. When using the Apt PDGF/Apt thr29-Au NPs as selectors for the enrichment of PDGF and for the removal of interferences from cell media, the LOD for PDGF provided by this probe is 35pM. The present probe reveals that the concentration of PDGF in the three cell media is 230 (±20)pM, showing its advantages of simplicity, sensitivity, and specificity. © 2011 Elsevier B.V.

Chou W.-C.,National Taiwan Ocean University | Gong G.-C.,National Taiwan Ocean University | Gong G.-C.,Taiwan Ocean Research Institute | Cai W.-J.,University of Delaware | Tseng C.-M.,National Taiwan University
Biogeosciences | Year: 2013

Model studies suggested that human-induced increase in nutrient load may have stimulated primary production and thus enhanced the CO2 uptake capacity in the coastal ocean. In this study, we investigated the seasonal variations of the surface water's partial pressure of CO2 (pCO 2 sw) in the highly human-impacted Changjiang-East China Sea system between 2008 and 2011. The seasonality of pCO2 sw has large spatial variations, with the largest extreme of 170 ± 75 μatm on the inner shelf near the Changjiang Estuary (from 271 ± 55 μatm in summer to 441 ± 51 μatm in autumn) and the weakest extreme of 53 ± 20 μatm on the outer shelf (from 328 ± 9 μatm in winter to 381 ± 18 μatm in summer). During the summer period, stronger stratification and biological production driven by the eutrophic Changjiang plume results in a very low dissolved inorganic carbon (DIC) in surface waters and a very high DIC in bottom waters of the inner shelf, with the latter returning high DIC to the surface water during the mixed period. Interestingly, a comparison with historical data shows that the average pCO2 sw on the inner shelf near the Changjiang Estuary has decreased notably during summer, but has increased during autumn and winter from the 1990s to the 2000s. We suggest that this decadal change is associated with recently increased eutrophication. This would increase both the photosynthetic removal of DIC in surface waters and the respiratory release of DIC in bottom waters during summertime, thereby returning more DIC to the surface during the subsequent mixing seasons and/or episodic extreme weather events (e.g., typhoons). Our finding demonstrates that increasing anthropogenic nutrient delivery from a large river may enhance the sequestration capacity of CO 2 in summer but may reduce it in autumn and winter. Consequently, the coastal ocean may not necessarily take up more atmospheric CO2 in response to increasing eutrophication, and the net effect largely depends on the relative timescale of air-sea gas exchange and offshore transport of the shelf water. Finally, the case we report for the Changjiang system may have general ramifications for other eutrophic coastal oceans. © Author(s) 2013.

Chen P.-C.,National Taiwan University | Ma J.-Y.,National Taiwan University | Chen L.-Y.,National Taiwan University | Lin G.-L.,National Taiwan University | And 3 more authors.
Nanoscale | Year: 2014

A facile and one-pot approach to the preparation of gold (Au) and copper (Cu) bimetallic nanoclusters (NCs) is unveiled. AuCu NCs reveal features of orange photoluminescence (PL), reversible pH-dependent PL properties, and efficient catalytic activity for degradation of methylene blue (MB). This journal is © the Partner Organisations 2014.

Lee Y.-F.,National Taiwan Ocean University | Deng T.-W.,National Taiwan Ocean University | Chiu W.-J.,National Taiwan Ocean University | Wei T.-Y.,National Taiwan Ocean University | And 2 more authors.
Analyst | Year: 2012

We have developed a simple, low-cost, paper-based probe for the selective colorimetric detection of copper ions (Cu 2+) in aqueous solutions. The bovine serum albumin (BSA)-modified 13.3-nm Au nanoparticle (BSA-Au NP) probe was designed to detect Cu 2+ ions using lead ions (Pb 2+) and 2-mercaptoethanol (2-ME) as leaching agents in a glycine-NaOH (pH 12.0) solution. In addition, a nitrocellulose membrane (NCM) was used to trap the BSA-Au NPs, leading to the preparation of a nanocomposite film consisting of a BSA-Au NP-decorated membrane (BSA-Au NPs/NCM). The BSA-Au NPs probe operates on the principle that Cu deposition on the surface of the BSA-Au NPs inhibits their leaching ability, which is accelerated by Pb 2+ ions in the presence of 2-ME. Under optimal solution conditions (5 mM glycine-NaOH (pH 12.0), Pb 2+ (50 μM), and 2-ME (1.0 M)), the Pb 2+/2-ME-BSA-Au NPs/NCM enabled the detection of Cu 2+ at nanomolar concentrations in aqueous solutions by the naked eye with high selectivity (at least 100-fold over other metal ions). In addition, this cost-effective probe allowed for the rapid and simple determination of Cu 2+ ions in not only natural water samples but also in a complex biological sample (in this case, blood sample). © 2012 The Royal Society of Chemistry.

Zhang Y.-M.,Shandong University of Technology | Gu Y.,Shandong University of Technology | Chen J.-T.,National Taiwan Ocean University
Engineering Analysis with Boundary Elements | Year: 2011

Thin structures have been widely designed and utilized in many industries. However, the analysis of the mechanical behavior of such structures represents a very challenging and attractive task to scientists and engineers because of their special geometrical shapes. The major difficulty in applying the boundary element method (BEM) to thin structures is the coinstantaneous existence of the singular and nearly singular integrals in conventional boundary integral equation (BIE). In this paper, a non-linear transformation over curved surface elements is introduced and applied to the indirect regularized boundary element method for 2-D thin structural problems. The developed transformation can remove or damp out the nearly singular properties of the integral kernels, based on the idea of diminishing the difference of the orders of magnitude or the scale of change of operational factors. For the test problems studied, very promising results are obtained when the thickness to length ratio is in the orders of 1E-01 to 1E-06, which is sufficient for modeling most thin structures in industrial applications. © 2010 Elsevier Ltd.

Zhang Y.-M.,Shandong University of Technology | Zhang Y.-M.,Dalian University of Technology | Gu Y.,Shandong University of Technology | Gu Y.,Dalian University of Technology | Chen J.-T.,National Taiwan Ocean University
Engineering Analysis with Boundary Elements | Year: 2011

Various thin-coating films are designed and utilized for industrial applications to improve machining performance due to better temperature and wear resistant properties than their substrate counterparts. However, the widespread experimental research on thin coatings underlies a general lack of modeling efforts, which can accurately and efficiently predict the coating and thin film performance. In this paper, the boundary element method (BEM) for 2D elastostatic problems is studied for the analysis of single and multilayered coating systems. The nearly singular integrals, which is the primary obstacle associated with the BEM formulations, are dealt efficiently by using a general nonlinear transformation technique. For the test problems studied, very promising results are obtained when the thickness of coated layers is in the orders of 1.0E-6 to 1.0E-9, which is sufficient for modeling most coated systems in the micro- or nano-scales. © 2010 Elsevier Ltd.

Lin C.-K.,National Taiwan Ocean University | Liu T.-H.,National Taiwan University of Science and Technology | Yu J.-T.,National Taiwan University | Fu L.-C.,National Taiwan University | Hsiao C.-F.,National Taiwan University of Science and Technology
IEEE Transactions on Industrial Electronics | Year: 2014

A model-free predictive current control (PCC) of interior permanent-magnet synchronous motor (IPMSM) drive systems based on a current difference detection technique is proposed. The model-based PCC (MBPCC) of IPMSM requires knowledge of parameters such as resistance, q-axis inductance, and extended back EMF. This paper develops a new model-free approach that alleviates the need for excessive prior knowledge about the system and only utilizes the stator currents as well as the current differences corresponding to different switching states of the inverter. Despite the salient difference of the proposed approach, it adopts a measure similar to that in the MBPCC approach to obtain the next switching state of the inverter by minimizing a cost function. It is noteworthy that the proposed method is easy to implement due to its simplicity and free of any multiplication operation. For comparison purposes, a digital signal processor, TMS320LF2407, is used to execute the two aforementioned current control techniques. Several experimental results show that the proposed method can significantly improve the current-tracking performance. © 1982-2012 IEEE.

Chen Y.-M.,National Taiwan University | Hung W.-Y.,National Taiwan Ocean University | You H.-W.,National Taiwan Ocean University | Chaskar A.,National Taiwan University | And 4 more authors.
Journal of Materials Chemistry | Year: 2011

In this study, we synthesized a series of bipolar hosts (CbzCBI, mCPCBI, CbzNBI, and mCPNBI) containing hole-transporting carbazole and electron-transporting benzimidazole moieties and then examined the morphological, thermal, and photophysical properties and carrier mobilities of these bipolar host materials. Altering the linking topology (C- or N-connectivity of the benzimidazole) changed the effective conjugation length and led to different excited-state solvent relaxation behavior. The N-connected compounds (CbzNBI, mCPNBI) possessed higher triplet energies (ET) than those of their C-connected analogues (CbzCBI, mCPCBI) by 0.23 eV. The higher values of ET of CbzNBI and mCPNBI endowed them with the ability to confine triplet excitons on the blue-emitting guest. A blue PhOLED device incorporating mCPNBI achieved a maximum external quantum efficiency, current efficiency, and power efficiency of 16.3%, 35.7 cd A-1, and 23.3 lm W-1, respectively; confirming the suitability of using N-connected bipolar hosts for the blue phosphor. The donor/acceptor interactions of the C-connected analogue resulted in a lower triplet energy, making it a suitable bipolar host for green phosphors. A green-phosphorescent device incorporating CbzCBI as the host doped with (PBi)2Ir(acac) achieved a maximum external quantum efficiency, current efficiency, and power efficiency of 20.1%, 70.4 cd A-1, and 63.2 lm W-1, respectively. This journal is © The Royal Society of Chemistry.

Lin C.-C.,National Taiwan Ocean University | Tu H.-L.,National Taiwan University
Theoretical Computer Science | Year: 2015

In a graph G, a vertex subset S⊆. V(G) is said to be a dominating set of G if every vertex not in S is adjacent to a vertex in S. A dominating set S of a graph G is called a paired-dominating set if the induced subgraph G[. S] contains a perfect matching. The paired-domination problem involves finding a minimum paired-dominating set of G. For this problem, Chen et al. [J. Comb. Optim. 19 (4) (2010) 457-470] proposed an O(n+. m)-time algorithm on interval graphs and Cheng et al. [Discrete Appl. Math. 155 (16) (2007) 2077-2086] designed an O(m(n+. m))-time algorithm on circular-arc graphs. In this paper, we strengthen the results of Cheng et al. by showing an O(n+. m)-time algorithm. Moreover, the algorithm can be completed in O(n) time if an intersection model of a circular-arc graph G with sorted endpoints is given. Since interval graphs are circular-arc graphs, we also obtain a linear time algorithm on interval graphs. © 2015 Elsevier B.V.

Wang C.-I.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University | Lin Y.-W.,National Changhua University of Education | Chen W.-T.,National Taiwan University | Chang H.-T.,National Taiwan University
Analytica Chimica Acta | Year: 2012

In this study, we developed a fluorescence assay for the highly sensitive and selective detection of Hg2+ and Pb2+ ions using a gold nanoparticle (Au NP)-based probe. The Hg-Au and Pb-Au alloys that formed on the Au NP surfaces allowed the Au NPs to exhibit peroxidase-mimicking catalytic activity in the H2O2-mediated oxidation of Amplex UltraRed (AUR). The fluorescence of the AUR oxidation product increased upon increasing the concentration of either Hg2+ or Pb2+ ions. By controlling the pH values of 5mM tris-acetate buffers at 7.0 and 9.0, this H2O2-AUR-Au NP probe detected Hg2+ and Pb2+ ions, respectively, both with limits of detection (signal-to-noise ratio: 3) of 4.0nM. The fluorescence intensity of the AUR oxidation product was proportional to the concentrations of Hg2+ and Pb2+ ions over ranges 0.05-1μM (R2=0.993) and 0.05-5μM (R2=0.996), respectively. The H2O2-AUR-Au NP probe was highly selective for Hg2+ (>100-fold) and Pb2+ (>300-fold) ions in the presence of other tested metal ions. We validated the practicality of this simple, selective, and sensitive H2O2-AUR-Au NP probe through determination of the concentrations of Hg2+ and Pb2+ ions in a lake water sample and of Pb2+ ions in a blood sample. To the best of our knowledge, this system is the first example of Au NPs being used as enzyme-mimics for the fluorescence detection of Hg2+ and Pb2+ ions. © 2012 Elsevier B.V.

Lin Y.-W.,National Changhua University of Education | Huang C.-C.,National Taiwan Ocean University | Chang H.-T.,National Taiwan University
Analyst | Year: 2011

Monitoring the levels of potentially toxic metal (PTM) ions (e.g., Hg 2+, Pb2+, Cu2+) in aquatic ecosystems is important because these ions can have severe effects on human health and the environment. Gold (Au) nanomaterials are attractive sensing materials because of their unique size- and shape-dependent optical properties. This review focuses on optical assays for Hg2+, Pb2+, and Cu2+ ions using functionalized Au nanomaterials. The syntheses of functionalized Au nanomaterials are discussed. We briefly review sensing approaches based on changes in absorbance resulting from metal ion-induced aggregation of Au nanoparticles (NPs) or direct deposition of metal ions onto Au NPs. The super-quenching properties of Au NPs allow them to be employed in 'turn on' and 'turn off' fluorescence approaches for the sensitive and selective detection of Hg2+, Pb2+, and Cu2+ ions. We highlight approaches based on fluorescence quenching through analyte-induced aggregation or the formation of metallophilic complexes of Au nanodots (NDs). We discuss the roles of several factors affecting the selectivity and sensitivity of the nanosensors toward the analytes: the size of the Au nanomaterial, the length and sequence of the DNA or the nature of the thiol, the surface density of the recognition ligand, and the ionic strength and pH of the buffer solution. In addition, we emphasize the potential of using new nanomaterials (e.g., fluorescent silver nanoclusters) for the detection of PTM ions. © 2011 The Royal Society of Chemistry.

Luo T.-N.,National Taiwan University | Wu C.-H.E.,National Taiwan Ocean University | Chen Y.-J.E.,National Taiwan University
IEEE Transactions on Circuits and Systems I: Regular Papers | Year: 2013

This paper presents a 77-GHz long-range automotive radar transceiver with the function of reducing mutual interference. The proposed frequency-hopping random chirp FMCW technique reconfigures the chirp sweep frequency and time every cycle to result in noise-like frequency response for mutual interference after the received signal is down-converted and demodulated. Thus, the false alarm rate can be reduced significantly. The transceiver IC is fully integrated in TSMC 1P9M 65-nm digital CMOS technology. The chip including pads occupies a silicon area of 1.03 mm$\,\times\,$0.94 mm. The transceiver consumes totally 275 mW of power, and the measured transmitting power and receiver noise figure are 6.4 dBm and 14.8 dB, respectively. To the authors' knowledge, this is the first integrated 77-GHz automotive radar transceiver with the feature of anti-interference. © 2013 IEEE.

Kuo S.R.,National Taiwan Ocean University | Yang Y.B.,National Taiwan University | Yang Y.B.,National Yunlin University of Science and Technology
Engineering Structures | Year: 2013

If a nonlinear plate theory is to be valid, it should work in the extreme case of rigid displacements. For this case, the strain energy vanishes as the strains are zero, but the instability potential of the initial forces acting on the plate does not. This is idea for deriving the instability potential of an initially stressed plate using the updated Lagrangian coordinates. For given real rigid displacements, an instability potential was derived for the plate based on the rigid body rule. Next, for given virtual rigid displacements, another instability potential was derived for the plate utilizing the equilibrium equations for the boundary tractions at the C1 and C2 states. By comparing the two instability potentials for the real and virtual rigid displacements, the total instability potential was recovered, which differs from the existing ones in the inclusion of the torsional terms. The total instability potential derived, along with the strain energy available, was adopted in the nonlinear analysis of structures involving torsional actions, by which the superiority of the present theory was demonstrated. The present theory is featured by the fact that virtually no kinematic hypothesis was adopted in the formulation. © 2012 Elsevier Ltd.

Tsai S.-W.,Chang Gung University | Liou H.-M.,National Taiwan Ocean University
Micro and Nanosystems | Year: 2013

Over the past several decades, many in vitro three-dimensional hepatocyte culture systems have been established, including collagen sandwiches, Matrigel™ cultures and microencapsulation systems. In addition, several studies have shown that materials with galactose ligands conjugated to their surfaces can improve hepatocyte attachment and allow the cells to maintain most of their functions. Pectin is a heterogeneous polymer of α-(1-4)-D-galacturonic acid with varying degrees of esterification and neutral sugar substitution and a variable molecular weight. In our work, we utilized pectin as a matrix to encapsulate hepatocytes. We evaluated the cellular functions of hepatocytes encapsulated in pectin and compared these functions with those of cells encapsulated in alginate. Based on the results of this work, we concluded that encapsulated HepG2 cells in pectin gel had a higher viability and superior urea synthesis function than cells in alginate microcapsules. © 2013 Bentham Science Publishers.

Ye L.,CAS Wuhan Institute of Hydrobiology | Ye L.,National Taiwan University | Chang C.-Y.,National Taiwan University | Garcia-Comas C.,National Taiwan University | And 3 more authors.
Journal of Animal Ecology | Year: 2013

The biodiversity-ecosystem functioning debate is a central topic in ecology. Recently, there has been a growing interest in size diversity because body size is sensitive to environmental changes and is one of the fundamental characteristics of organisms linking many ecosystem properties. However, how size diversity affects ecosystem functioning is an important yet unclear issue. To fill the gap, with large-scale field data from the East China Sea, we tested the novel hypothesis that increasing zooplankton size diversity enhances top-down control on phytoplankton (H1) and compared it with five conventional hypotheses explaining the top-down control: flatter zooplankton size spectrum enhances the strength of top-down control (H2); nutrient enrichment lessens the strength of top-down control (H3); increasing zooplankton taxonomic diversity enhances the strength of top-down control (H4); increasing fish predation decreases the strength of top-down control of zooplankton on phytoplankton through trophic cascade (H5); increasing temperature intensifies the strength of top-down control (H6). The results of univariate analyses support the hypotheses based on zooplankton size diversity (H1), zooplankton size spectrum (H2), nutrient (H3) and zooplankton taxonomic diversity (H4), but not the hypotheses based on fish predation (H5) and temperature (H6). More in-depth analyses indicate that zooplankton size diversity is the most important factor in determining the strength of top-down control on phytoplankton in the East China Sea. Our results suggest a new potential mechanism that increasing predator size diversity enhances the strength of top-down control on prey through diet niche partitioning. This mechanism can be explained by the optimal predator-prey body-mass ratio concept. Suppose each size group of zooplankton predators has its own optimal phytoplankton prey size, increasing size diversity of zooplankton would promote diet niche partitioning of predators and thus elevates the strength of top-down control. © 2013 British Ecological Society.

Lin S.-M.,National Taiwan Ocean University | Nelson W.A.,NIWA - National Institute of Water and Atmospheric Research
European Journal of Phycology | Year: 2010

Two species of Phycodrys, Phycodrys quercifolia (Bory) Skottsberg and Phycodrys profunda E.Y.Dawson were previously recorded from New Zealand. However, an examination of Phycodrys collections from the New Zealand region showed that all were morphologically different from P. quercifolia (Type locality: the Falkland Islands) and P. profunda (Type locality: CA, USA). RbcL sequence analyses established that the New Zealand Phycodrys species formed a natural assemblage within the genus, consisting of three new species: P. novae-zelandiae sp. nov., P. franiae sp. nov. and P. adamsiae sp. nov. Phycodrys novae-zelandiae is the largest of the three, up to 20 cm in height, with a distinct midrib and multicellular, opposite to subopposite lateral macroscopic veins. It has entirely monostromatic blades except near the midrib and veins, and its procarp contains a three-celled sterile group one (st1) and a one-celled sterile group two (st2). Phycodrys franiae was previously treated as a cryptic species among herbarium collections of P. 'quercifolia'. It is smaller (4-11 cm high) with weakly developed midribs and veins, the blade is tristromatic throughout, except at the growing margins, and the procarp consists of a four-celled st1 and a two-three-celled st2. Phycodrys adamsiae, previously reported as P. profunda, is a small decumbent or prostrate plant, 1-8 cm long, with a midrib and inconspicuous lateral veins. The blades are tristromatic with serrated margins, two-four-celled surface spines and multicellular marginal holdfasts that differ from those of Californian specimens. The tetrasporangia are borne on marginal bladelets. Phylogenetic analyses place the New Zealand species in a separate group that is distantly removed from most other Phycodrys species. © 2010 British Phycological Society.

Chen C.-J.,National Taiwan Ocean University | Chu T.-H.,National Taiwan University
IEEE Transactions on Microwave Theory and Techniques | Year: 2011

S-matrix reconstruction transforms are based on two stages of matrix transformation to remove the mismatch-induced errors. Over the years, these transforms are widely used in measurements of multiport devices using a two-port vector network analyzer, especially for noncoaxial applications because high-quality matched loads are hardly accessible. In this paper, analytical error analysis of the S-matrix reconstruction transforms is performed to develop the accuracy criterion that is explicitly expressed in matrix form in terms of the S-matrix of the multiport device and the reflection coefficient matrix of the auxiliary terminations. The analytical insights in this paper can pave the way for using strongly reflecting auxiliary terminations. For noncoaxial measurements, strongly reflecting termination, such as a short-circuited or an open-circuited transmission line is more repeatable, reliable, and economical than terminations with loss like resistors. Consequently, the use of strongly reflecting auxiliary terminations is speculated to ease noncoaxial multiport measurements. © 2011 IEEE.

Kao M.-T.,National Taiwan University | Hung W.-Y.,National Taiwan Ocean University | Tsai Z.-H.,National Taiwan Ocean University | You H.-W.,National Taiwan Ocean University | And 3 more authors.
Journal of Materials Chemistry | Year: 2011

A simple, bilayered, red phosphorescent organic light-emitting device featuring a doubly-doped emitting layer comprising of the novel hole-transporting host DTAF, the electron-transporting host 27SFBI, and the emitter Os(bpftz)2(PPhMe2)2 covering the interfacial region provides an unusually high current of ca. 1560 mA cm -2 at 8.5 V, a maximum brightness of 32700 cd m-2, external quantum efficiencies as high as 12.3% (10.9% at 1000 cd m -2), and a power efficiency of 13.5 lm W-1. This concise device architecture is very cost-effective and competitive for practical applications. © 2011 The Royal Society of Chemistry.

Chang G.W.,National Chung Cheng University | Chuang C.-S.,National Chung Cheng University | Lu T.-K.,National Taiwan Ocean University | Wu C.-C.,Taiwan Power
IEEE Transactions on Power Systems | Year: 2013

The purpose of unit commitment (UC) for electric utilities is to determine the optimal thermal unit on/off statuses and their MW generations over the scheduled time horizon. The UC problem is formulated to minimize the total generation cost, while the load demand, reserve requirements, and unit constraints are satisfied. Among the UC constraints, an adequate provision of reserve is important to ensure the security of the power system and the frequency-regulating reserve is essential to bring the system frequency back to acceptable level following the loss of a sizable online unit within seconds. In this paper, the authors present and solve a mixed-integer linear programming (MILP)-based UC problem including the frequency-regulating reserve (FRR) constraints to determine the optimal FRR requirements and unitMWschedules for an isolated power system. Simulation results are then compared with those obtained by Lagrangian relaxation-based approach and by the current Taipower operation practice. It is observed that favorable reserve and unit MW schedules are obtained by the proposed method while the system security is maintained. © 2012 IEEE.

Mondal E.,National Taiwan University | Hung W.-Y.,National Taiwan Ocean University | Chen Y.-H.,National Taiwan Ocean University | Cheng M.-H.,National Taiwan Ocean University | And 2 more authors.
Chemistry - A European Journal | Year: 2013

Two new molecules, CzFCBI and CzFNBI, have been tailor-made to serve as bipolar host materials to realize high-efficiency electrophosphorescent devices. The molecular design is configured with carbazole as the hole-transporting block and N-phenylbenzimidazole as the electron-transporting block hybridized through the saturated bridge center (C9) and meta-conjugation site (C3) of fluorene, respectively. With structural topology tuning of the connecting manner between N-phenylbenzimidazole and the fluorene core, the resulting physical properties can be subtly modulated. Bipolar host CzFCBI with a C connectivity between phenylbenzimidazole and the fluorene bridge exhibited extended π conjugation; therefore, a low triplet energy of 2.52 eV was observed, which is insufficient to confine blue phosphorescence. However, the monochromatic devices indicate that the matched energy-level alignment allows CzFCBI to outperform its N-connected counterpart CzFNBI while employing other long-wavelength- emitting phosphorescent guests. In contrast, the high triplet energy (2.72 eV) of CzFNBI imparted by the N connectivity ensures its utilization as a universal bipolar host for blue-to-red phosphors. With a common device configuration, CzFNBI has been utilized to achieve highly efficient and low-roll-off devices with external quantum efficiency as high as 14 % blue, 17.8 % green, 16.6 % yellowish-green, 19.5 % yellow, and 18.6 % red. In addition, by combining yellowish-green with a sky-blue emitter and a red emitter, a CzFNBI-hosted single-emitting-layer all-phosphor three-color-based white electrophosphorescent device was successfully achieved with high efficiencies (18.4 %, 36.3 cd A -1, 28.3 lm W-1) and highly stable chromaticity (CIE x=0.43-0.46 and CIE y=0.43) at an applied voltage of 8 to 12 V, and a high color-rendering index of 91.6. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hsieh C.T.,National Taiwan University | Chu C.Y.,National Taiwan Ocean University | Shiue R.K.,National Taiwan University | Tsay L.W.,National Taiwan Ocean University
Materials and Design | Year: 2014

Dissimilar welding of the Ti-6Al-4V (Ti-6-4) to Ti-6A1-6V-2Sn (Ti-6-6-2) alloys was performed by CO2 laser in this work. The effect of post-weld heat treatment (PWHT) on the notched tensile strength (NTS) of the dissimilar weld was evaluated. Moreover, the results were also compared with the homogeneous laser welds with the same PWHT. Similar to the Ti-6-4 welds, the NTS of the FZ for dissimilar welds was less sensitive to PWHT conditions; the NTS of the FZ for distinct dissimilar welds fell within the range of 1060-1180MPa. The results indicated a minor rise in the Mo equivalent of the titanium alloy promoted the formation of fine α+β microstructures in the form of basket weave in the welds, which resulted in high hardness accompanied with low NTS of the welds. © 2014 Elsevier Ltd.

Cai W.-J.,University of Georgia | Hu X.,University of Georgia | Huang W.-J.,University of Georgia | Murrell M.C.,U.S. Environmental Protection Agency | And 12 more authors.
Nature Geoscience | Year: 2011

Human inputs of nutrients to coastal waters can lead to the excessive production of algae, a process known as eutrophication. Microbial consumption of this organic matter lowers oxygen levels in the water1-3. In addition, the carbon dioxide produced during microbial respiration increases acidity. The dissolution of atmospheric carbon dioxide in ocean waters also raises acidity, a process known as ocean acidification. Here, we assess the combined impact of eutrophication and ocean acidification on acidity in the coastal ocean, using data collected in the northern Gulf of Mexico and the East China Sea-two regions heavily influenced by nutrient-laden rivers. We show that eutrophication in these waters is associated with the development of hypoxia and the acidification of subsurface waters, as expected. Model simulations, using data collected from the northern Gulf of Mexico, however, suggest that the drop in pH since pre-industrial times is greater than that expected from eutrophication and ocean acidification alone. We attribute the additional drop in pH - of 0.05 units - to a reduction in the ability of these carbon dioxide-rich waters to buffer changes in pH. We suggest that eutrophication could increase the susceptibility of coastal waters to ocean acidification. © 2011 Macmillan Publishers Limited. All rights reserved.

Chang C.-W.,National Taiwan University | Tan W.-C.,National Taiwan University | Lu M.-L.,National Taiwan University | Pan T.-C.,National Taiwan Ocean University | And 2 more authors.
Advanced Functional Materials | Year: 2013

Advanced materials that combine novel functionality and ease of applicability are central to the development of light-emitting diodes (LEDs), which is of ever increasing commercial importance. Here a new metal-insulator-semiconductor (MIS) LED structure that combines economical fabrication with novel device properties is reported. The presented MIS-LED consists of a graphene electrode on p-GaN substrate separated by an insulating SiO2 layer. It is found that the MIS-LED possesses a unique tunability of the electroluminescence spectra depending on the bias conditions. Tunnel injection from graphene into the p-GaN can explain the difference in luminescence spectra under forward and reverse bias. The demonstrated MIS-LED expands the use of graphene and also possibly allows the direct integration of light emitters with other circuit elements. Metal-insulator-semiconductor (MIS) light- emitting diodes (LEDs) consisting of a graphene electrode on p-GaN substrate separated by an insulating SiO2 layer are reported. The novel MIS-LEDs have a unique tunability of the electroluminescence (EL) spectra depending on the bias conditions. The underlying mechanism can be interpreted as the tunneling of electrons and holes through the insulating layer in both polarities, which is different from the standard p-n junction model. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Mondal E.,National Taiwan University | Hung W.-Y.,National Taiwan Ocean University | Dai H.-C.,National Taiwan Ocean University | Wong K.-T.,National Taiwan University
Advanced Functional Materials | Year: 2013

Two new bipolar host molecules composed of hole-transporting carbazole and electron-transporting cyano (CzFCN) or oxadiazole (CzFOxa)-substituted fluorenes are synthesized and characterized. The non-conjugated connections, via an sp3-hybridized carbon, effectively block the electronic interactions between electron-donating and -accepting moieties, giving CzFCN and CzFOxa bipolar charge transport features with balanced mobilities (10-5 to 10-6 cm2 V-1 s-1). The meta-meta configuration of the fluorene-based acceptors allows the bipolar hosts to retain relatively high triplet energies [ET = 2.70 eV (CzFOxa) and 2. 86 eV (CzFCN)], which are sufficiently high for hosting blue phosphor. Using a common device structure - ITO/PEDOT:PSS/DTAF/TCTA/host:10% dopants (from blue to red)/DPPS/LiF/Al - highly efficient electrophosphorescent devices are successfully achieved. CzFCN-based devices demonstrate better performance characteristics, with maximum ηext of 15.1%, 17.9%, 17.4%, 18%, and 20% for blue (FIrpic), green [(PPy)2Ir(acac)], yellowish-green [m-(Tpm)2Ir(acac)], yellow [(Bt)2Ir(acac)], and red [Os(bpftz)2(PPhMe2)2, OS1], respectively. In addition, combining yellowish-green m-(Tpm)2Ir(acac) with a blue emitter (FIrpic) and a red emitter (OS1) within a single emitting layer hosted by bipolar CzFCN, three-color electrophosphorescent WOLEDs with high efficiencies (17.3%, 33.4 cd A-1, 30 lm W -1), high color stability, and high color-rendering index (CRI) of 89.7 can also be realized. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Liu C.-S.,Hohai University | Liu C.-S.,National Taiwan Ocean University
International Journal of Heat and Mass Transfer | Year: 2016

In order to recover the unknown heat source H(t)/H(x) in the heat conduction equation, we introduce homogenized functions and differencing equations, which can significantly simplify the solution procedures for the inverse heat source recovery problem. We only need to solve a few linear equations in the problem domain, since the initial condition/boundary conditions and a supplementary condition are satisfied automatically, and the differencing technique is employed to eliminate the heat source terms in the linear equations. The Pascal polynomials and eigenfunctions are adopted as trial functions to expand the trial solutions, and then some small scale linear systems are solved to determine the expansion coefficients. Because the ill-posedness of the inverse heat source recovery problem is greatly reduced, the present methods are accurate and stable against large noise up to 20%, which are confirmed by the numerical tests. © 2016 Elsevier Ltd.

Ting H.-C.,National Taiwan University | Chen Y.-M.,National Taiwan University | You H.-W.,National Taiwan Ocean University | Hung W.-Y.,National Taiwan Ocean University | And 6 more authors.
Journal of Materials Chemistry | Year: 2012

By incorporating electron-accepting benzimidazole and electron-donating indolo[3,2-b]carbazole into one molecule, two novel donor-acceptor bipolar host materials, TICCBI and TICNBI, have been synthesized. The photophysical and electrochemical properties of the hybrids can be tuned through the different linkages (C- or N-connectivity) between the electronic donor and acceptor components. The promising physical properties of these two new compounds made them suitable for use as hosts doped with various Ir or Os-based phosphors for realizing highly efficient phosphorescent organic light emitting diodes (PhOLEDs). PhOLEDs using TICCBI and TICNBI as hosts incorporated with Ir-based emitters such as green (PPy) 2Ir(acac), yellow (Bt) 2Ir(acac), and two new red emitters (35dmPh-6Fiq) 2Ir(acac) (i3) and (4tBuPh-6Fiq) 2Ir(acac) (i6) accomplished high external quantum efficiencies ranging from 14 to 16.2%. Nevertheless, the red PhOLED device incorporating TICNBI doped with the red emitter osmium(ii) bis[3-(trifluoromethyl)-5-(4-tert-butylpyridyl)-1,2,4-triazolate] dimethylphenylphosphine [Os(bpftz) 2(PPhMe 2) 2] achieved a maximum external quantum efficiency, current efficiency, and power efficiency of 22%, 28 cd A -1, and 22.1 lm W -1, respectively, with CIE coordinates of (0.65,0.35). The external quantum efficiency remained high (20%) as the brightness reached to 1000 cd m -2, suggesting balanced charge fluxes within the emitting layer, rendering devices with limited efficiency roll-off. © The Royal Society of Chemistry 2012.

Shiang Y.-C.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University | Wang T.-H.,National Taiwan Ocean University | Chien C.-W.,National Taiwan Ocean University | Chang H.-T.,National Taiwan University
Advanced Functional Materials | Year: 2010

Thrombin-binding aptamer-conjugated gold nanoparticles (TBA-Au NPs) for highly effective control of thrombin activity towards fibrinogen are demonstrated. While a 29-base long oligonucleotide (TBA29) has known no enzymatic inhibitory functions for thrombin-mediated coagulation, the ultrahigh anticoagulant potency of TBA29-Au NPs can be demonstrated via the steric blocking effect, at two orders of magnitude higher than that of free TBA29. The surface aptamer density on the Au NPs is important in determining their enzymatic inhibition of thrombin and their stability in the presence of nuclease. The practicality of 100TBA29-Au NPs (100 TBA29 molecules per Au NP) for controlling thrombin-mediated coagulation in plasma is found, and the 100TBA29-Au NPs has an ultra binding affinity towards thrombin (Kd 2.7 × 10-11m) due to their high ligand density. The anticoagulant activity of TBA 29-Au NPs is found to be suppressed by TBA29 complementary sequence (cTBA29) modified Au NPs (cTBA29-Au NPs), with a suppression rate 4.6- fold higher than that of cTBA29 The easily prepared and low-cost TBA29-Au NPs and cTBA29-Au NPs show their potential in biomedical applications for treating various diseases related to blood clotting disorders. In principle, this study opens the possibility of regulation of molecule binding, protein recognizing, and enzyme activity by using aptamer-functionalized nanomaterials. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA.

Luo T.-N.,National Taiwan University | Wu C.-H.E.,National Taiwan Ocean University | Chen Y.-J.E.,National Taiwan University
IEEE Transactions on Microwave Theory and Techniques | Year: 2013

This paper presents a 77-GHz CMOS frequencymodulated continuous-wave (FMCW) frequency synthesizer with the capability of reconfigurable chirps. The frequency-sweep range and sweep time of the chirp signals can be reconfigured every cycle such that the frequency-hopping random chirp signal can be realized for an FMCW radar transceiver. The frequency synthesizer adopts the fractional- phase-locked-loop technique and is fully integrated in TSMC 65-nm digital CMOS technology. The silicon area of the synthesizer is 0.65 mm 0.45 mm and it consumes 51.3 mW of power. The measured output phase noise of the synthesizer is 85.1 dBc/Hz at 1-MHz offset and the root-mean-square modulation frequency error is smaller than 73 kHz. © 2013 IEEE.

Hung W.-Y.,National Taiwan Ocean University | Chi L.-C.,National Taiwan University | Chen W.-J.,National Taiwan Ocean University | Chen Y.-M.,National Taiwan University | And 2 more authors.
Journal of Materials Chemistry | Year: 2010

The bipolar molecule CPhBzIm exhibits an excellent solid state photoluminescence quantum yield (ΦPL = 69%), triplet energy (ET = 2.48 eV), and bipolar charge transport ability (μh ≈ μe ≈ 10-6-10-5 cm2 V-1 s-1). We have used it to fabricate a non-doped deep-blue organic light emitting diode (OLED) exhibiting promising performance [ηext = 3%; CIE = (0.16, 0.05)] and to serve as host material for a yellow-green phosphorescent OLED [ηext = 19.2%; CIE = (0.42, 0.56)]. Exploiting these dual roles, we used CPhBzIm in a simple singly doped, two-color-based white OLED (ηext = 7%; CIE = 0.31, 0.33). © 2010 The Royal Society of Chemistry.

Ahyong S.T.,NIWA - National Institute of Water and Atmospheric Research | Chan T.-Y.,National Taiwan Ocean University
Zootaxa | Year: 2010

A new species of king crab is described from Taiwan, Lithodes formosae sp. nov. The new species resembles L. longispina Sakai, 1971, from Japan, L. megacantha Macpherson, 1991, from French Polynesia, and L. paulayi Macpherson & Chan, 2008, from Guam, in having long dorsal spines in adults, though it is most similar to L. paulayi. Lithodes formosae is distinguished from the aforementioned species primarily by differing branchial spine arrangement and proportional spine length. Comparison of partial cytochrome oxidase subunit I (COI) gene sequences from L. formosae sp. nov., L. paulayi and L. longispina supports the specific status of the new species. Six species of Lithodidae are known from Taiwan, of which L. formosae sp. nov. is the first to be described as new from Taiwan. Copyright © 2010 Magnolia Press.

Tsai S.-W.,Chang Gung University | Yu D.-S.,National Taiwan Ocean University | Tsao S.-W.,Chang Gung University | Hsu F.-Y.,National Taiwan Ocean University
International Journal of Nanomedicine | Year: 2013

Hyaluronan-cisplatin conjugate nanoparticles (HCNPs) were chosen as colon-targeting drug-delivery carriers due to the observation that a variety of malignant tumors overexpress hyaluronan receptors. HCNPs were prepared by mixing cisplatin with a hyaluronan solution, followed by dialysis to remove trace elements. The cells treated with HCNPs showed significantly lower viability than those treated with cisplatin alone. HCNPs were entrapped in Eudragit S100-coated pectinate/alginate microbeads (PAMs) by using an electrospray method and a polyelectrolyte multilayer-coating technique in aqueous solution. The release profile of HCNPs from Eudragit S100-coated HCNP-PAMs was pH-dependent. The percentage of 24-hour drug release was approximately 25.1% and 39.7% in pH 1.2 and pH 4.5 media, respectively. However, the percentage of drug released quickly rose to 75.6% at pH 7.4. Moreover, the result of an in vivo nephrotoxicity study demonstrated that Eudragit S100-coated HCNP-PAMs treatment could mitigate the nephrotoxicity that resulted from cisplatin. From these results, it can be concluded that Eudragit S100-coated HCNP-PAMs are promising carriers for colon- specific drug delivery. © 2013 Tsai et al, publisher and licensee Dove Medical Press Ltd.

Hsieh C.-H.,Asia University, Taiwan | Chang W.-T.,National Penghu University of Science and Technology | Chang H.C.,Asia University, Taiwan | Hsieh H.-S.,Asia University, Taiwan | And 2 more authors.
Food Chemistry | Year: 2010

To identify the mislabeled or fraudulently substituted toxic puffer fish in thermally processed fish products, a polymerase chain reaction (PCR) method using restriction sites and sequence analysis has been developed in this study. A 376-bp fragment of the cytochrome b gene was produced after PCR amplification. Fish tissue samples were prepared under autoclaving conditions at 121 °C for 10-90 min at 10 min intervals. DNA fragments could not be detected after 90 min of autoclaving at 121 °C. For PCR product digestion, BsaJ I, Aci I, Hinf I, Taq I, and Sap I endonucleases were used to yield species-specific profiles for the identification of puffer fish species from 60 commercial market samples. Results from this study showed that the restriction fragment length polymorphism technique can be used to identify 17 puffer fish species from commercial products even after severe thermal processing. © 2010 Elsevier Ltd. All rights reserved.

Zhang Y.,Shandong University of Technology | Gu Y.,Shandong University of Technology | Chen J.-T.,National Taiwan Ocean University
Engineering Analysis with Boundary Elements | Year: 2010

Temperature measurement and prediction have been a major focus of machining for several decades, but now these problems become more complex due to the wider use of advanced cutting tool coatings. In all literature items cited the boundary element method (BEM) were used to find the distribution of temperature inside the uncoated tool body or along the tool-chip interface in the machining processes. The BEM-based approach proposed in this paper overcomes this limit and the temperature distribution in thin coated layers is well studied. In this study, a general strategy based on a nonlinear transformation technique is introduced and applied to evaluate the nearly singular integrals occurring in two dimensional (2D) thin-coated structures. For the test problems studied, very promising results are obtained when the thickness to length ratio is in the orders of 1.0E-6 to 1.0E-10, which is sufficient for modeling most thin-coated structures in the micro- or nano-sclaes. © 2010 Elsevier Ltd. All rights reserved.

Hung W.-Y.,National Taiwan Ocean University | Chi L.-C.,National Taiwan University | Chen W.-J.,National Taiwan Ocean University | Mondal E.,National Taiwan University | And 3 more authors.
Journal of Materials Chemistry | Year: 2011

A novel bipolar molecule CNBzIm comprised of electron-donating carbazole and electron-accepting phenylbenzimidazole is designed, synthesized and characterized for RGB phosphorescent organic light emitting diodes (PhOLEDs). CNBzIm exhibits promising properties such as high triplet energy (ET = 2.71 eV) due to disrupted π-conjugation, bipolar and balanced charge transport ability (μh ≈ μe ≈ 10-5 cm2 V-1 s-1), and high morphological stability (Tg = 185 °C). PhOLEDs adopted CNBzIm as a host respectively doped with Os(bpftz)2(PPh2Me)2, (PPy) 2Ir(acac) and FIrpic under the same device structure show excellent performance with external quantum efficiencies (ηext) as high as 19.1% for red, 17.8% for green, and 12.7% for blue. A two-color, all-phosphor and single-emitting-layer WOLED hosted by CNBzIm was achieved with a maximum ηext of 15.7%, current efficiency (ηc) of 35 cd A-1, and power efficiency (ηp) of 36.6 lm W -1. Utilizing a bipolar host with balanced mobilities, WOLED can effectively broaden its recombination zone and show high color stability. The Commission Internationale de L'Eclairage (CIE) coordinates of the WOLED remain almost constant when the brightness goes from 1700 cd m-2 (0.32, 0.41) to 49900 cd m-2 (0.31, 0.41). © 2011 The Royal Society of Chemistry.

Tsai W.-P.,National Taiwan Ocean University | Tsai W.-P.,National Taiwan University | Liu K.-M.,National Taiwan Ocean University | Joung S.-J.,National Taiwan Ocean University
Marine and Freshwater Research | Year: 2010

The pelagic thresher shark, Alopias pelagicus, like most large sharks produces a low number of offspring (two embryos per litter). However, there is no accurate information on its population status. To improve the accuracy of population simulations, a stochastic stage-based birth-flow model was constructed to assess the stock status of the pelagic thresher in the north-western Pacific. Based on the best biological information available, its life history was represented as four stages: neonates, juveniles, subadults, and adults. Results indicated that, without mortality from fishing, the stock would clearly increase (mean annual population growth rate (λ)=1.058 year -1, 95% CI=1.0141.102 year-1). When current fishing mortality was taken into account, a decrease in population was indicated (λ=0.979 year-1, 95% CI= 0.921-1.030year-1) with a projected reduction of 34.3% over 20 years. These results suggest that the stock is overexploited. Simulations using various management measures showed that the population will remain steady under these protection options. However, this species is extremely vulnerable to overexploitation and is especially sensitive at the juvenile and adult stages, implying that nursery closures or size limit management measures are urgently needed to ensure the sustainable utilisation of the stock.

Komai T.,Natural History Museum and Institute | Chan T.-Y.,National Taiwan Ocean University
Zootaxa | Year: 2010

Two new species of alvinocaridid shrimps are described from a hydrothermal vent field off northeastern Taiwan at depths of 252-300 m. Alvinocaris chelys n. sp. is morphologically very similar to A. williamsi Shank & Martin, 2003 from the Mid-Atlantic Ridge, and A. alexander Ahyong, 2009 from the southern Kermadec Ridge. These three species can be differentiated by the shape of the postrostral ridge, telson, the second segment of the antennular peduncle and the armature of the meri and ischia of the third pereopod. The second new species, although rather similar to Alvinocaris niwa Webber, 2004 from the Kermadec-Arc, is assigned to a new genus Alvinocaridinides gen. nov., which appears to be intermediate between Shinkaicaris Komai & Segonzac, 2005 and other derived genera including Opaepele Williams & Dobbs, 1995, Chorocaris Martin & Hessler, 1990 and Rimicaris Williams & Rona, 1986. Alvinocaridinides formosa n. sp. differs from Alvinocaris niwa by completely lacking any armature on the ischia of the third to fifth pereopods and by bearing two movable spines at the posterolateral angle of the uropodal exopod. These records constitute the first discovery of the family Alvinocarididae in Taiwanese waters and represent the shallowest occurrence for alvinocaridid shrimps. Copyright © 2010 Magnolia Press.

Komai T.,Natural History Museum and Institute | Lin F.-J.,National Cheng Kung University | Chan T.-Y.,National Taiwan Ocean University
Zootaxa | Year: 2010

One new genus and five new species of axiid burrowing shrimps are described from deep-waters around Taiwan: Formosaxius dorsum n. gen., n. sp.; Ambiaxius propinquus n. sp., Calastacus formosus n. sp.; Eiconaxius rubrirostris n. sp. and E. kensleyi n. sp. The new genus, Formosaxius, appears closest to Bouvieraxius Sakai & de Saint Laurent, 1989 in the arrangement and armature of the gastric carinae on the carapace and the possession of pleurobranchs, but the presence of appendices internae on the third to fifth pleopods readily separates the new genus from Bouvieraxius. Affinities of the other four new species are also discussed. This study raises the number of species of Axiidae known from Taiwan to 13. Copyright © 2010 Magnolia Press.

Chung H.Y.,Academia Sinica, Taiwan | Leung P.T.,Academia Sinica, Taiwan | Leung P.T.,National Taiwan Ocean University | Leung P.T.,Portland State University | And 2 more authors.
Optics Express | Year: 2013

The modified fluorescence properties of a molecule in the vicinity of a metallic nanoparticle are further studied accounting for the possible existence of extraneous charges on the particle surface. This is achieved via a generalization of the previous theory of Bohren and Hunt for light scattering from a charged sphere, with the results applied to the calculation of the various decay rates and fluorescence yield of the admolecule. Numerical results show that while charge effects will in general blue-shift all the plasmonic resonances of the metal particle, both the quantum yield and the fluorescence yield can be increased at emission frequencies close to that of the surface plasmon resonance of the particle due to the suppression of the nonradiative decay rate. This provides a possibility of further enhancing the particle-induced molecular fluorescence via the addition of surface charge to the metal particle. ©2013 Optical Society of America.

Guan P.C.,National Taiwan Ocean University | Chi S.W.,University of California at Los Angeles | Chen J.S.,University of California at Los Angeles | Slawson T.R.,U.S. Army | Roth M.J.,U.S. Army
International Journal of Impact Engineering | Year: 2011

Fragment-impact problems exhibit excessive material distortion and complex contact conditions that pose considerable challenges in mesh based numerical methods such as the finite element method (FEM). A semi-Lagrangian reproducing kernel particle method (RKPM) is proposed for fragment-impact modeling to alleviate mesh distortion difficulties associated with the Lagrangian FEM and to minimize the convective transport effect in the Eulerian or Arbitrary Lagrangian Eulerian FEM. A stabilized non-conforming nodal integration with boundary correction for the semi-Lagrangian RKPM is also proposed. Under the framework of semi-Lagrangian RKPM, a kernel contact algorithm is introduced to address multi-body contact. Stability analysis shows that temporal stability of the kernel contact algorithm is related to the velocity gradient between two contacting bodies. The performance of the proposed methods is examined by numerical simulation of penetration processes. © 2011 Elsevier Ltd. All rights reserved.

Chen C.-J.,National Taiwan Ocean University | Chu T.-H.,National Taiwan University
Asia-Pacific Microwave Conference Proceedings, APMC | Year: 2010

The characteristics of three existing S-matrix reconstruction transforms on the multiport network characterization are studied for the case of using a single kind of auxiliary terminations. Three unifying properties are discerned and experimentally verified. It is found that the three existing S-matrix transforms prefer auxiliary terminations with small reflection coefficients. When auxiliary terminations with large reflection coefficients are taken, it may encounter numerical difficulty whose destructiveness depends inversely on the power loss of the device under test. These findings may lead more studies on the cause and remedy of the numerical difficulty. © 2010 IEICE Institute of Electronics Informati.

Chang S.-C.,National Taiwan Ocean University | Komai T.,Natural History Museum and Institute | Chan T.-Y.,National Taiwan Ocean University
Journal of Crustacean Biology | Year: 2010

The hippolytid shrimp genus Lebbeus White, 1847 was previously unknown from Taiwan. However, recent deep-sea surveys off the island have collected numerous specimens comprising four species, three of which are new to science: L. tosaensis Hanamura and Abe, 2003, L. brevirostris n. sp., L. formosus n. sp., and L. unguiculatus n. sp. Lebbeus brevirostris belongs to the group bearing epipods only on the first two pereiopods and is unique in having a short spiniform rostrum. Lebbeus formosus and L. unguiculatus bear epipods on the first three pereiopods. The latter is characteristic in having the dactyli of the posterior pereiopods terminating in a single elongate unguis. Lebbeus formosus is distinct in having a combination of rostral, antennular, telson, and pereiopodal characters. © 2010 The Crustacean Society.

Wang C.-S.,National Taiwan University | Chang T.-Y.,National Taiwan Ocean University | Lin T.-Y.,National Taiwan Ocean University | Chen Y.-F.,National Taiwan University
Scientific Reports | Year: 2014

Quasi-periodic structures of natural biomaterial membranes have great potentials to serve as resonance cavities to generate ecological friendly optoelectronic devices with low cost. To achieve the first attempt for the illustration of the underlying principle, the Pieris canidia butterfly wing was embedded with ZnO nanoparticles. Quite interestingly, it is found that the bio-inspired quasi-single-mode random laser can be achieved by the assistance of the skeleton of the membrane, in which ZnO nanoparticles act as emitting gain media. Such unique characteristics can be interpreted well by the Fabry-Perot resonance existing in the window-like quasi-periodic structure of butterfly wing. Due to the inherently promising flexibility of butterfly wing membrane, the laser action can still be maintained during the bending process. Our demonstrated approach not only indicates that the natural biological structures can provide effective scattering feedbacks but also pave a new avenue towards designing bio-controlled photonic devices.

Liu S.-H.,National Taiwan University | Chang Y.-H.,National Taiwan Ocean University | Chiang M.-T.,National Taiwan Ocean University
Journal of Agricultural and Food Chemistry | Year: 2010

Chitosan is a natural and versatile biomaterial with a blood-glucose- lowering effect in diabetic animals, but the mechanism of action is still unknown. This study was designed to investigate the possible mechanisms involved in the hypoglycemic activity of chitosan in rats with streptozotocin (STZ)-induced diabetes. Male Sprague-Dawley (SD) rats were divided into non-diabetic with cellulose (control), diabetic with cellulose (DM), and diabetic with low-(DM + LCS) and high-(DM + HCS) molecular-weight chitosan groups. After a 4 week feeding study, plasma glucose and fructosamine levels were increased while plasma leptin was decreased in the DM group when compared to the control group. These alternations caused by diabetes could be effectively reversed by both chitosan treatments. The increased gluconeogenesis-related signals including phosphoenolpyruvate carboxykinase (PEPCK) expression and phosphorylations of p38 and AMP-activated kinase (AMPK) in the livers of diabetic rats were attenuated by chitosans. Moreover, chitosan significantly increased muscle glucose uptake-related signals including Akt phosphorylation and glucose transporter-4 (GLUT4) translocation from the cytosol to membrane in the soleus muscles of diabetic rats. These results indicate that chitosan may possess a potential for alleviating type-1 diabetic hyperglycemia through the decrease in liver gluconeogenesis and increase in skeletal muscle glucose uptake and use. © 2010 American Chemical Society.

Wei C.-L.,National Taiwan University | Lin S.-Y.,National Taiwan University | Sheu D.-D.,National Sun Yat - sen University | Chou W.-C.,National Taiwan Ocean University | And 3 more authors.
Biogeosciences | Year: 2011

The time-series station, SEATS (18°N, 116°E) in the South China Sea was visited six times during October 2006-December 2008 to carry out seawater sampling and floating trap deployments for the determination of distributions and fluxes of POC, PIC, PN, 234Th, 210Pb, and 210Po in the upper 200 m of the water column. Radionuclide deficiencies resulted in removal fluxes from the euphotic layer of 1.1×10 3-1.8×10 3 dpm m -2d -1 and 7.1-40.2 dpm m -2d -1 for 234Th and 210Po, respectively. Due to atmospheric input, an excess of 210Pb relative to 226Ra is commonly observed in the upper water column. Sinking fluxes of total mass, POC, PIC, PN, 234Th, 210Pb, and 210Po measured at the euphotic depth were low in summer-fall and high in winter-spring, reflecting the seasonal variability of biological pumping. Excluding the suspiciously low primary productivity data point in July 2007, a relatively high e-ratio of 0.28-0.69 was estimated by the ratio of the POC flux at the euphotic depth and the integrated primary productivity. The ratios of 234Th, 210Pb, and 210Po to organic carbon, inorganic carbon, and nitrogen in the sinking particles were combined with the disequilibria of 234Th- 238U, 210Pb- 226Ra, and 210Po- 210Pb to estimate export fluxes of POC, PIC, and PN from the euphotic layer. Compared with measured fluxes by the sediment trap and estimated fluxes by other approaches, it is concluded that the export production in the South China Sea, ranging from 1.8 to 21.3 mmol-C m -2d -1, can be reasonably estimated using 234Th, 210Pb, and 210Po as carbon proxies. © 2011 Author(s).

Tseng Y.-T.,National Taiwan Ocean University | Chang H.-T.,National Taiwan University | Chen C.-T.,National Taiwan University | Chen C.-H.,National Taiwan University | Huang C.-C.,National Taiwan Ocean University
Biosensors and Bioelectronics | Year: 2011

In this paper, we describe a novel, simple, and convenient method for preparing water-soluble biofunctional gold nanodots (Au NDs) for the sensitive and selective detection of Escherichia coli (E. coli) and the inhibition of its growth. We obtained luminescent mannose-capped Au NDs (Man-Au NDs) from as-prepared 2.9-nm Au nanoparticles (Au NPs) and 29,29′-dithio bis(3′,6′,9′,12′,15′,18′-hexaoxa-nonacosyl α-d-mannopyranoside) (Man-RSSR-Man). To obtain improved quantum yield (>20%), luminescent Man-Au NDs (1.8nm) were prepared from Au NPs (0.47μM) and Man-RSSR-Man (2.5mM) in the presence of sodium borohydride (NaBH 4; 1.0mM). The highly luminescent properties of Man-Au NDs prepared by the NaBH 4-assisted method were characterized by UV-vis absorption, photoluminescence, and X-ray photoelectron spectroscopies. The results supported the high-density coverage of the NDs surface by Man-RS ligands. Multivalent interactions between Man-Au NDs and FimH proteins located on the bacterial pili of E. coli resulted in the formation of aggregated cell clusters. After concentrating this agglutinative E. coli from a large-volume cell solution (5mL), Man-Au NDs were displaced by mannose (100mM) and stabilized by Man-RSSR-Man (5mM). Monitoring the luminescence of Man-Au NDs allowed the detection of E. coli at levels as low as 150CFU/mL. Man-Au NDs were also found to be efficient antibacterial agents, selectively inhibiting the growth of E. coli through Man-Au ND-induced agglutination. Our small-diameter Man-Au NDs, which provided an ultra high ligand density (local concentration) of mannose units for multivalent interactions with E. coli, have great potential for use as an antibacterial agent in other applications. © 2011 Elsevier B.V.

Huang J.-H.,Oriental Institute of Technology | Chang R.,National Taiwan Ocean University
Journal of Optics (United Kingdom) | Year: 2014

Strong coupling between a molecule and a metallic nanosphere clad by a layer of gain medium, which provides compensation for losses in the metal, is investigated theoretically. We self-consistently solve the classical model of a molecule which is described as a damped oscillating dipole, driven by the field reflected back from the metallic surface. It is found that in a broad range of gain level, the frequencies of this coupled system exhibit a splitting substantially larger than the associated damping rate, a signature of strong coupling. As the gain-dissipation balance is optimized, strong coupling occurs even if the molecule is separated from the nanoparticle by a distance as large as several tens of nanometers. Thus through the aid of a gain medium, experimental observation of strong coupling can be easily achieved. © 2014 IOP Publishing Ltd.

Huang J.-H.,National Taiwan Ocean University | Huang J.-H.,Oriental Institute of Technology | Chang R.,National Taiwan Ocean University
Journal of Optics A: Pure and Applied Optics | Year: 2010

We present a theoretical study on the dispersion relation for surface plasmons at a metal-Kerr medium interface where the metal is described by a nonlocal dielectric function according to the hydrodynamic model. The Kerr effect leads to a shift of the surface plasmon frequency depending on the electric field intensity, the magnitude as well as the sign of the Kerr coefficient, and the wavevector. We further observe that this frequency shift is largely quenched for large wavenumbers for which the nonlocal effect is significantly manifested. We account for this quenching quantitatively by a calculation showing how the nonlocality weakens the sensitivity in the metal's response to the variation of the dielectric function of the Kerr medium. A possible experimental observation of this new effect is briefly discussed. © 2010 IOP Publishing Ltd.

Yang C.-Y.,National Taiwan Ocean University | Hsu C.-H.,National Taiwan Ocean University | Hsu C.-H.,Food and Beverage | Tsai M.-L.,National Taiwan Ocean University
Carbohydrate Polymers | Year: 2011

In this study, tripolyphosphate/genipin co-crosslinked chitosan beads were prepared in different pH solutions and applied for selective adsorption of phytic acid from soybean whey solution. The co-crosslinking degrees (81.20-59.22%) of beads decreased with increased pH value of solution. The major chemical linkage between chitosan and genipin and a little ionic interaction between chitosan and tripolyphosphate gave CB7 (co-crosslinked in pH 7 solution) the best mechanical strength among these beads. The best adsorption ratio of phytic acid of the co-crosslinked beads occurred in pH 1 solution. The adsorption ratios of CB7 for phytic acid, trypsin inhibitor and lectin from pH 2 soybean whey solution were 30.23%, 3.76% and 1.53%, respectively. The highest desorption ratio of phytic acid from the CB7 desorbed in pH 9 solution was 93.98%; selective isolation for phytic acid can definitely be processed by CB7. © 2011 Elsevier Ltd All rights reserved.

Hsiao S.-H.,National Taipei University of Education | Fang T.-H.,National Taiwan Ocean University
Marine Pollution Bulletin | Year: 2013

The Hg concentration in seawater and copepod samples collected from the area around hydrothermal vents at Kueishan Island and the adjacent marine environment in northeastern Taiwan were analyzed to study Hg bioaccumulation in copepods living in polluted and clean marine environments. The seawater collected from the hydrothermal vent area had an extremely high concentration of dissolved Hg, 50.6-256ngl-1. There was slightly higher Hg content in the copepods, 0.08-0.88μgg-1. The dissolved Hg concentration in the hydrothermal vent seawater was two to three orders of magnitude higher than that in the adjacent environment. The bioconcentration factor of the studied copepods ranged within 103-106, and showed higher dissolved concentration as the bioconcentration factor was lower. A substantial abundance, but with less copepod diversity was recorded in the seawater around the hydrothermal vent area. Temora turbinata was the species of opportunity under the hydrothermal vent influence. © 2013.

Li L.-Y.,University of Birmingham | Xia J.,University of Birmingham | Xia J.,Zhejiang University | Lin S.-S.,National Taiwan Ocean University