Taiwan University

Taiwan, Taiwan

Taiwan University

Taiwan, Taiwan
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Wang L.,China Jiliang University | Xie R.-J.,Xiamen University | Xie R.-J.,Japan National Institute of Materials Science | Li Y.,Intematix | And 8 more authors.
Light: Science and Applications | Year: 2016

Color rendition, luminous efficacy and reliability are three key technical parameters for white light-emitting diodes (wLEDs) that are dominantly determined by down-conversion phosphors. However, there is usually an inevitable trade-off between color rendition and luminescence efficacy because the spectrum of red phosphor (that is, spectral broadness and position) cannot satisfy them simultaneously. In this work, we report a very promising red phosphor that can minimize the aforementioned trade-off via structure and band-gap engineering, achieved by introducing isostructural LiSi2N3 into CaAlSiN3:Eu2+. The solid solution phosphors show both substantial spectra broadening (88→117 nm) and blueshift (652→642 nm), along with a significant improvement in thermal quenching (only a 6% reduction at 150 °C), which are strongly associated with electronic and crystal structure evolutions. The broadband and robust red phosphor thus enables fabrication of super-high color rendering wLEDs (Ra=95 and R9=96) concurrently with the maintenance of a high-luminous efficacy (101 lm W- 1), validating its superiority in highperformance solid state lightings over currently used red phosphors. © The Author(s) 2016.

Chung Y.-F.,Tunghai University | Chen Y.-T.,National Chiao Tung University | Chen T.-L.,Taiwan University | Chen T.-S.,Tunghai University
Expert Systems with Applications | Year: 2011

Rapid development of the Internet and the extensive use of mobile phones have increased demand for mobile devices in Internet auctions. This trend is acting as an incentive to develop an auction model for mobile-based environment. Recently, Kuo-Hsuan Huang proposed a mobile auction agent model (MoAAM), which allows the bidders to participate in online auctions through a mobile agent. He used modular exponentiation operations in his method. As a result, the processing time for key generation, bidding, and verification were long. Thus, we propose to add the concept of Elliptic Curve Cryptosystem (ECC) onto MoAAM, because ECC has low computation amount and small key size, both of which will aid to increase the speed in generating keys, bidding, and verification. In terms of reduction of computation load on mobile devices and auction-manager server, the proposed method will make online auction system more efficient as well as more convenient to use. This paper mainly uses the English auction protocol as the key auction protocol. The protocol consists of four entities: Registration Manager (RM), Agent House (AH), Auction House (AUH), and Bidders (B). The Registration Manager registers and verifies Bidder identity. The Agent House manages the agents and assigns public transaction keys to Bidders. The Auction House provides a place for auction and maintains all necessary operations for a smooth online auction. Bidders are buyers who are interested in purchasing items at the auction. Our proposed method conforms to the requirements of an online auction protocol in terms of anonymity, traceability, no framing, unforgetability, non-repudiation, fairness, public verifiability, unlinkability among various auction rounds, linkability within a single auction round, efficiency of bidding, one-time registration, and easy revocation. © 2011 Published by Elsevier Ltd.

Hsieh Y.,Taiwan University | Chan Y.,Institute of Earth science | Hu J.,Taiwan University | Lin C.,Central Geological Survey
Journal of Remote Sensing | Year: 2013

Taiwan is located in a subtropical region and issusceptible to typhoons and torrential rains during the summer seasons. Taiwan is also located on actively shifting tectonic plates that can cause dramatic terrain changes. Taiwan's river terrain frequently sustains substantial changes, especially after typhoons and torrential rains. Presently, digital terrain maps or models made by airborne LiDAR technology are reliable, have sufficient resolutions, are accurate, convenient, and can filter out buildings or tree cover to restore the original ground topography. This type of map or model can meet the requirements of geological and topographical analysis studies. In 2008, the Lanyang River region experienced four major typhoon events: Kalmaegi, Fung-Wong, Sinlaku, and Jangmi. These typhoons changed the riverbed terrain dramatically. Therefore, we used two occasions of digital terrain data measured using the airborne LiDAR system to conduct analytical comparisons of the riverbed terrain and river sediment transportation changes before and after typhoon events. The study is the first of its kind to demonstrate the excellent applications of the airborne LiDAR system for measuring river terrains in a large watershed area; digital terrain data were produced for periods before and after a typhoon season. We used the elevation difference topography measurement method to calculate river terrain changes before and after a typhoon season. This study's results showed that the airborne LiDAR high resolution digital terrain model data produced excellent results when used to calculate river terrain and sediment volume changes or change amounts.

Ma Y.,Xiamen University | Ouyang T.,Xiamen University | Chen O.-P.,Taiwan University | Chen C.-K.,Continental Water Engineering Corporation | Chang C.-T.,Ilan University
Journal of Nanoscience and Nanotechnology | Year: 2014

Polyaniline/titanium nanotube composite (PANI/TNT) photocatalysts were prepared by 'in situ' chemical oxidative polymerization of aniline. Transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform IR spectra (FTIR) and UV-Visible spectroscopy measurements were used to characterize the obtained photocatalysts, and their photocatalytic activities were investigated by degrading Reactive Green19 (RG19) under near visible light irradiation (λ = 365 nm). The content of PANI, pH, dosage, and concentration of RG19 were also investigated. The results showed that the inner diameter of the PANI/TNT was 6 nm and that the PANI did not change the structure of the TNT. The PANI was coated on the surface of the TNT. The light response of the PANI/TNT was extended to the visible-light regions. Among the six different kinds of photocatalysts, the 1.17 wt% PANI/TNT had the best performance in treating 10 ppm RG19. The best pH is 3 for the largely protonated surface of the composite at low pH. The adsorption amount was increased as the dosage increased. The decolonization efficiency decreased with increasing initial RG19 concentration. The performance of the photocatalyst in decomposing RG19 was stable after 5 time. Copyright © 2014 American Scientific Publishers. cycles. Copyright © 2014 American Scientific Publishers.

News Article | November 22, 2016
Site: www.24-7pressrelease.com

LE JULLE, CA, November 22, 2016-- Dr. Luke Mo has been included in Marquis Who's Who. As in all Marquis Who's Who biographical volumes, individuals profiled are selected on the basis of current reference value. Factors such as position, noteworthy accomplishments, visibility, and prominence in a field are all taken into account during the selection process.A physicist with experience in academia and research, Dr. Mo has been excelling in the field of science since establishing his career in 1963. During his tenure, he has worked as a research associate for Columbia University in New York City, a research physicist for the Stanford Linear Accelerator Program in Stanford, Calif., an assistant professor of physics at the University of Chicago, and a professor of physics at the Virginia Polytechnic Institute and State University. Driven by a passion for all areas of physics, he demonstrates an expertise that has earned him national recognition for his research and contributions. Dr. Mo attributes his success to his work ethic and ability to delve into a project wholeheartedly with dedication and commitment. In recognition of professional excellence exhibited throughout his career, he was named a Guggenheim fellow and he was selected for inclusion in Who's Who in America, Who's Who in Science and Engineering, Who's Who in the South and Southwest, and Who's Who in the World.Dr. Mo entered the field of physics research due to a seemingly innate interest in science that began at a young age. Prior to establishing himself professionally, he attended Taiwan University, where he earned a Bachelor of Science in electrical engineering in 1955. Thereafter, he earned a Master of Science in physics from National Tsinghua University in 1959, and a Ph.D. from Columbia University in 1963. As he progressed in his career, Dr. Mo also acted as a visiting professor at a number of universities, and contributed articles and chapters to professional journals and textbooks. He has remained an active force in the field of science through his membership with the American Physical Society. Although retired, Dr. Mo looks forward to accepting advisory opportunities as they arise.About Marquis Who's Who :Since 1899, when A. N. Marquis printed the First Edition of Who's Who in America , Marquis Who's Who has chronicled the lives of the most accomplished individuals and innovators from every significant field of endeavor, including politics, business, medicine, law, education, art, religion and entertainment. Today, Who's Who in America remains an essential biographical source for thousands of researchers, journalists, librarians and executive search firms around the world. Marquis now publishes many Who's Who titles, including Who's Who in America , Who's Who in the World , Who's Who in American Law , Who's Who in Medicine and Healthcare , Who's Who in Science and Engineering , and Who's Who in Asia . Marquis publications may be visited at the official Marquis Who's Who website at www.marquiswhoswho.com

Lu R.,China University of Geosciences | He D.,China University of Geosciences | Suppe J.,Taiwan University | Ma X.,China University of Geosciences | And 3 more authors.
Scientia Geologica Sinica | Year: 2010

In this paper, the fine interpretations of seismic profiles in the central Longmen Mountains have been accomplished with application of fault-related fold geometry principles. Studies find that there are multi-detachment layers with different structural deformation in the shallow thrusting system of Longmen Mountains front belt. The upper level detachment layer is the Upper Triassic Xujiahe Formation (T 3x 3), which develop the imbricate structures and duplex; The middle level detachment layers are the Lower Triassic Jialingjiang Formation (T 1j 4-5), which develop the fault-propagation folds, pop-up structures and structural wedges; The lower level detachment layer is the Lower Cambrian formation and develop fault-bend folds and detachment-folds; These detachments control the deformation with different shortenings. The shortening of the Upper Triassic formation is more than 30 km and below the Lower Triassic formation is about 14.5 km. The strata which above the Triassic formation with few shortening. In this research area, the Tongjichang fault(F 3) were a set of thrusting faults, which were developing during the Late Indosinian periods. They were rooted in the Lower Cambrian detachment with the depth about 10 km. The Guankou fault(F 4) and Pengxian fault(F 5) both were rooted in the Lower Triassic Jialingjiang detachment and with the depth about 8~10 km. They are brittle and active faults, which were breaking-forward during the Late Jurassic-Early Cretaceous periods. After the Mesozoic Era, There are muti-tectonic events in the central Longmen Mountains. The Late Norian stage, the Late Indosinian epoch, the Yanshan and the Himalayan period are the typical times of tectonic movements in this area. Among them, the latter two periods are the most intense tectonic movements, which made a large number of thrusting faults and developed different structural styles. It also led the crust shortening and uplifting quickly.

Li Q.,Huaqiao University | Yang Y.-C.,Taiwan University | Wang L.-Q.,Huaqiao University
Chinese Journal of New Drugs | Year: 2014

Objective: To investigate the uptake, transepithelial transport characteristics and cellular uptake mechanism of TW918 in the Caco-2 cell model.Methods: The Caco-2 cell model was established and used to study the absorption and transportation of TW918. The monolayer integrity of Caco-2 cells and function of the P-gp were detected by HPLC, and transepithelial resistance (TER) of monolayer cells was measured. The uptake of TW918 was investigated by the factors including time, pH and concentration. The bidirectional transfer speed of drug at different times was measured and the apparent permeability was calculated.Results: Cell monolayer with the properties of good compactness, integrity, and functionality was formed in both of the uptake and transport tests. The uptake of TW918 in Caco-2 cells showed a linear range in 20 min and the uptake time was fixed at 10 min. No significant pH-dependent influence was observed in Caco-2 cells. The concentration-dependent uptake of TW918 consisted of one saturable and one nonsaturable component. Verapamil almost had no effect on the uptake of TW918, and MK571 increased the uptake significantly (P<0.05). The permeability showed directional difference (P<0.05), and decreased significantly with increasing of concentration.Conclusion: The absorption of TW918 in Caco-2 cells includes active and passive manners, and involves in efflux transport; MRP2 maybe play an important role in the efflux of TW918 in Caco-2 cells. ©, 2014, Chinese Journal of New Drugs Co. Ltd. All right reserved.

Chen T.-L.,Taiwan University | Chung Y.-F.,Tunghai University | Lin F.Y.S.,Taiwan University
Expert Systems with Applications | Year: 2010

The core competencies of a mobile agent includes its ability to roam freely in different Internet environments, its ability to adapt itself to various types of online servers depending on the characteristics of said server, and its ability to detect its environment and automatic adaptation to said environment while executing the tasks that are assigned by the users. Because of these competencies, the concept of mobile agent is widely used in many different fields, such as Internet business, wireless communication, and information security technologies. Akl and Taylor (1983) suggested the concept of superkey to resolve the key management issues faced by the mobile agent. Later, Volker and Mehrdad (1998) proposed a tree base mobile agent model for access control. The proposed scheme is based upon the studies of public key and a hierarchical mobile agent model with addition of Elliptic Curve Cryptosystem (ECC). ECC enhances the operational ability of mobile agent model, because of shorter key length and higher efficiency on encryption and decryption. In addition, after a period of time, due to error or change in the user's rights, said user will be forced to log out of the system. At the same time, to prevent a user from continuing to use the old key, the system must keep modifying the key so as to change the original access rights of the key, this action could cause unnecessary error and risks, in addition to the large amount of computations that the system needs to perform. Hence, this paper proposes date-constraint key management scheme, where a date is attached to the key, so as to give a validity period to the key. Thus, key management can be more efficient. © 2010 Elsevier Ltd. All rights reserved.

Song J.,Yantai University | Wang X.,Yantai University | Chen O.-P.,Taiwan University | Chen C.-K.,Continental Water Engineering Corporation | Chang C.-T.,Ilan University
Separation Science and Technology (Philadelphia) | Year: 2015

Graphene-titanium nanotube composites with different ratios of graphite oxide were prepared via the hydrothermal method using ascorbic acid as a reducing agent. Properties of materials were characterized by X-ray diffraction, Fourier Transform Infrared Spectroscopy, high resolution transmission electron microscopy and UV–vis diffuse reflectance spectroscopy. The average diameter of the titanium dioxide nanotubes was about 8 nm. The photoresponse of nanocomposites have been extended to visible-light regions. In addition, graphene-titanium nanotube composites showed higher photocatalytic degradation efficiency for reactive black 5 (RBK5) than pure titanium dioxide and the 15%graphene-titanium nanotube composites catalysts possessed the best photocatalytic activity. The degradation efficiency for RBK5 dyes increased with increased dosage of graphite oxide from 3%-15% and decreased with increasing initial RBK5 concentration. This paper not only reports the fabrication of highly active photocatalysts but also provides insight into the photocatalytic mechanism of graphene-titanium nanotube composites. Copyright © Taylor & Francis Group, LLC.

Huang N.,Lanzhou University | Zhang Y.,Lanzhou University | Zhang Q.,Taiwan University | Chen C.-K.,Continental Water Engineering Corporation | Chang C.-T.,Ilan University
Journal of Nanoscience and Nanotechnology | Year: 2014

TiO2 nanotubes were prepared by hydrothermal process, then characterized using Brunauer-Emmett-Teller (BET), transmission electron microscopy (TEM), X-ray diffraction (XRD) and UV-Visible spectroscopy measurements. The photodegradation performance assessment of Reactive Red 141 (RR141) with near visible light irradiation (λ = 380 nm) was carried out under different catalyst doses, dye concentrations, pH and initial Cr(VI) concentrations by TiO2 powder and nanotubes. The results showed that the specific surface area of TiO2 nanotubes were 152 m2 g-1, about three times larger than that of TiO2 powder which was roughly 51 m2 g-1. The TiO2 nanotubes did not affect the lattice structure of the TiO2. The adsorption amount increases as the dosage and RR141 concentration increases. However, the decolonization efficiency decreased with increasing initial RR141 concentration. Results also showed that an acidic solution is more favorable for photocatalytic degradation of RR141. On the other hand, Cr(VI) can be adsorbed on the surface of TiO2 nanotubes to affect the decolonization efficiency of RR141. Copyright © 2014 American Scientific Publishers.

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