Huanan, China
Huanan, China

Time filter

Source Type

Yang H.-A.,National Chiao Tung University | Yang W.-H.,National Chiao Tung University | Chen K.-H.,National Chiao Tung University | Wey C.-L.,National Chiao Tung University | And 5 more authors.
Digest of Technical Papers - IEEE International Solid-State Circuits Conference | Year: 2016

Lighting flicker, a rapid and repeated change over time in the brightness of light, has long been known to cause illness in humans that ranges from headaches to seizures. Thus, [1] has specified the dimming frequency, fDIM, larger than 3kHz to achieve a no-observable-effect flicker level. State-of-the-art LED drivers employ the SIMO topology with four channels in Fig. 12.7.1, to deliver energy to each LED using the time-multiplexing (TM) control technique [2-4], in which the luminance is controlled by the dimming signals. Two major shortcomings for such approaches are: (1) Sequential dimming signals; and (2) Current cross-regulation (CCR) effects. In [2], the LED drivers with TM control result in only 9b color resolution at the dimming frequency of 1.5kHz, which may cause flicker hazard. Besides, the complete white-red-green-blue (WRGB) sequence needs a total of four switching periods to light up the 4 LEDs separately. On the other hand, due to inherent rising and falling delay of the hysteretic current control (HCC) circuit, tdr and tdf respectively, the CCR effect seriously affects the accuracy of the controller when the inductor current slope is varied. For example, with L=15μH, VIN=20V, VR=2.5V, VG=3.5V, tdr=300ns and tdf=250ns, the SIMO will result in 4% CCR between Iavg,R and Iavg,G when the average LED current is 1A. More specifically, with the same color in the sequence, voltage regulation may be disregarded when regulated constant current through the sensing resistor RSEN is used as a negative feedback control. However, when different colors are in sequence, where VO, =VR, VG, VB, or VW, are different, large voltage cross-regulation (VCR) across the RSEN occurs and so does the CCR. The CCR effects become an open question for enhancing LED current accuracy. For alleviating the CCR effect, the discontinuous conduction mode (DCM) has been applied for TM control in [3]. However, with the limited output current in DCM, low output power resulted and large output capacitors were required to suppress the VCR. © 2016 IEEE.

Lai S.-C.,Nan Hua University | Liu C.-H.,National Cheng Kung University | Wang L.-Y.,National Cheng Kung University | Chen S.-H.,National Chiao Tung University | Chen K.-H.,National Chiao Tung University
IEEE Transactions on Circuits and Systems I: Regular Papers | Year: 2015

This paper presents a novel algorithm and architecture design for 18-band quasi-class-2 ANSI S1.11 1/3 octave filterbank. The proposed design has several advantages such as lower group delay, lower computational complexity, and lower matching error. The technique we developed in this paper can be summarized as follows: 1) a simple low-pass filter (LPF) and discrete cosine transform (DCT) modulation are utilized to generate a uniform 9-band filterbank first, and then all elements of ${\rm z}-1 are replaced by all-pass filters to obtain a non-uniform filterbank; 2) a fast recursive structure and variable-length algorithm is further developed to efficiently accomplish DCT modulation. Thus, the spectrum of LPF can be easily spanned and flexibly extended to the location of the desired central frequency; 3) after employing the multi-rate algorithm, an 18-band non-uniform filterbank is generated from two 9-band sub filterbanks by following the proposed design steps and parameter determinations. Compared with the latest Liu 's quasi-class-2 ANSI S1.11 design, the proposed method-I (Proposed-I) totally has 72.8% reduction for multiplications per sample, 11.25-ms group delay, and 59 additions decreased per sample. Moreover, the maximum matching error of the proposed method-II (Proposed-II) is averagely equal to 1.79 dB much smaller than that of the latest Wei 's design. For the proposed variable-length DCT modulation, only 2 adders, 2 multipliers, 2 multiplexers, and 5 registers are required for hardware implementation after applying VLSI retiming scheme. Overall, the proposed filterbank design would be a new solution for future applications in the area of hearing aids. © 2004-2012 IEEE.

Li L.-Y.,Sun Yat Sen University | Gao X.,Sun Yat Sen University | Yang M.,Sun Yat Sen University | Li J.-F.,Nan Hua University | And 3 more authors.
Urology | Year: 2010

Objectives: To determine the systemic response to percutaneous nephrolithotomy (PCNL) and mini-PCNL (MPCNL) and evaluate whether MPCNL is less invasive than PCNL, as experimental studies suggest that the acute-phase reaction is proportional to surgery-induced tissue damage. Methods: In all, 165 consecutive patients who had undergone MPCNL (93) or PCNL (72) were prospectively assessed. Blood samples were collected 24 hours before; during surgery; at the end of anesthesia; and 12, 24, and 36 hours after surgery. The extent of the systemic response to surgery-induced tissue trauma was measured, by assessing the levels of acute-phase markers tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), IL-10, C-reactive protein (CRP), and serum amyloid A (SAA), at all sampling times in all patients. Results: No significant differences were observed between the 2 groups in preoperative variables. Baseline levels of TNF-α, IL-6, IL-10, CRP, and SAA were comparable in both groups. An increase was noted in TNF-α, IL-6, CRP, and SAA after surgery but no significant differences were assessed between MPCNL and PCNL during the entire period. IL-10 did not change at the different sampling times. Conclusions: Our data fail to demonstrate significant advantages of MPCNL in terms of reduced surgical trauma and associated invasiveness compared with standard PCNL based on the variables objectively measured in this study. © 2010 Elsevier Inc. All rights reserved.

Li A.-K.,National Cheng Kung University | Lei S.-F.,National Cheng Kung University | Tsai W.-K.,Industrial Technology Research Institute of Taiwan | Lai S.-C.,Nan Hua University
Proceedings - IEEE International Symposium on Circuits and Systems | Year: 2014

This paper proposed a novel fast algorithm and common structure design of analysis and synthesis quadrature mirror filterbanks (AQMF, SQMF) on the spectral band replication (SBR) in digital radio mondiale (DRM). Based on recent Lai et al.'s concept, an extended issue is addressed from the view point of recursively computing the AQMF and SQMF coefficients. The proposed method also combines with the lifting scheme algorithm and canonical signed digit (CSD) multiplication. The results show that the proposed AQMF algorithm has a great improvement on computational complexity. For the recursive kernel computation (N=64), the proposed method has, respectively, 46.38% of multiplication reductions and 20.46% of addition reductions which can cover the shortcoming of the proposed SQMF. The overall complexity of the proposed algorithm (N=64) requires 1984 real multiplication and 128 CSD multiplication, 4704 real addition and 192 CSD addition, and 113 coefficients. It would be more efficient and more suitable than previous works for DRM applications. © 2014 IEEE.

Lai S.-C.,Nan Hua University | Liu C.-H.,Nan Hua University | Wang L.-Y.,National Cheng Kung University | Lei S.-F.,National Cheng Kung University
Proceedings - 2014 10th International Conference on Intelligent Information Hiding and Multimedia Signal Processing, IIH-MSP 2014 | Year: 2014

This paper presents a novel algorithm design of 18-band quasi-class-2 ANSI S1.11 1/3 octave filter bank with the advantages of low group delay and low complexity. The proposed method utilizes a simple low-pass filter (LPF) and discrete cosine transform (DCT) modulation to generate a uniform 9-band filter bank first, and then transfer all element of z-1 into all-pass filter in order to obtain the non-uniform filter bank to meet the standard. Additionally, a fast recursive DCT algorithm is proposed to efficiently accomplish variable-length modulation. Hence, the spectrum of LPF can be easily spanned and flexibly extended to the position of the desired central frequency. Finally, by combining with multi-rate concept, we can realize an 18-band quasi-class-2 filter bank design. Compared with the latest Liu et al.'s quasi-class-2 ANSI S1.11 design, the proposed method totally has 63.4% reduction for multiplications per sample and 14-ms group delay, although we still have 15.2% increase for additions per sample. © 2014 IEEE.

Lai S.-C.,Nan Hua University | Lee M.-K.,National Cheng Kung University | Li A.-K.,National Cheng Kung University | Luo C.-H.,National Cheng Kung University | Lei S.-F.,National Cheng Kung University
IEEE Transactions on Circuits and Systems II: Express Briefs | Year: 2013

This brief presents a novel fast algorithm derivation and structure design of analysis and synthesis quadrature mirror filterbanks (SQMFs) on the spectral band replication in Digital Radio Mondiale (DRM). After the preprocedure and postprocedure, a Fourier-transform-based computational kernel was required to construct two types of fast algorithms that offered certain advantages. The Proposed-I method employs a modified split-radix fast Fourier transform (FFT) for analysis quadrature mirror filterbank (AQMF) to reduce the number of additions at the last stage of the butterfly and adopts a split-radix FFT to calculate the SQMF coefficients. The Proposed-II method used the compact structure of the variable-length recursive DFT to realize the kernel procedure for the proposed fast AQMF and SQMF algorithms. In addition, a well-known lifting scheme was applied to reduce numerous multiplication and addition calculations. Compared with the original calculations for the long transform length, all multiplication, addition, and coefficient operations for the Proposed-I method (i.e., AQMF + SQMF) had 91.65%, 79.81%, and 97.22% reductions, respectively. However, for the Proposed-II method, the total reductions of multiplication, addition, and coefficient operations were 64.16%, 21.53%, and 97.12%, respectively. Compared with the fast SQMF algorithm by Huang et al., the Proposed-I method for SQMF reduces 58.33% of the multiplication, 65% of the addition, and 67.19% of the coefficients. Therefore, the proposed fast quadrature mirror filterbank algorithm is a better solution than other approaches for future DRM applications. © 2004-2012 IEEE.

PubMed | National Cheng Kung University and Nan Hua University
Type: Journal Article | Journal: Sensors (Basel, Switzerland) | Year: 2016

This paper presents a portable low-power battery-driven bioelectrochemical signal acquisition system for urea detection. The proposed design has several advantages, including high performance, low cost, low-power consumption, and high portability. A LT1789-1 low-supply-voltage instrumentation amplifier (IA) was used to measure and amplify the open-circuit potential (OCP) between the working and reference electrodes. An MSP430 micro-controller was programmed to process and transduce the signals to the custom-developed software by ZigBee RF module in wireless mode and UART in able mode. The immobilized urease sensor was prepared by embedding urease into the polymer (aniline-co-o-phenylenediamine) polymeric matrix and then coating/depositing it onto a MEMS-fabricated Au working electrode. The linear correlation established between the urea concentration and the potentiometric change is in the urea concentrations range of 3.16 10(-4) to 3.16 10(-2) M with a sensitivity of 31.12 mV/log [M] and a precision of 0.995 (R = 0.995). This portable device not only detects urea concentrations, but can also operate continuously with a 3.7 V rechargeab-le lithium-ion battery (500 mAh) for at least four days. Accordingly, its use is feasible and even promising for home-care applications.

Chen S.-H.,Nan Hua University | Lee J.-M.,National Kaohsiung Marine University | Liu H.-H.,National Taipei University | Wang H.-C.,National Chung Hsing University | Ye C.-Y.,Overseas Chinese University
Health Policy and Planning | Year: 2011

This paper empirically identifies cross-price elasticities of betel nut and cigarette consumption in Taiwan based on the Central Bureau of Statistics demand model. It compares reduction of cigarette consumption as a result of the proposed Betel Nut Health Tax with reduction of betel nut consumption as a result of the Tobacco Health and Welfare Taxes levied in 2002 and 2006, in order to determine which tax is most effective. Results from a simulated comparative analysis indicate that the Betel Nut Health Tax reduces cigarette consumption to a much greater extent than the Tobacco Health and Welfare Taxes reduce betel nut consumption. © 2010 The Author.

Hung C.S.,Nan Hua University | Yen D.C.,Miami University Ohio | Ou C.S.,National Chung Cheng University
Journal of Engineering and Technology Management - JET-M | Year: 2012

More and more enterprises are taking advantage of self-service technologies (SSTs) in their customer-related operating activities, especially service firms. Although research on SSTs is prevalent, few studies have examined the impact of SSTs on firm financial performance. Given the growing importance of SSTs in the service industries in general and in the banking industry in particular, we therefore empirically examined the impacts of ATMs, one of the most widely accepted SSTs, on bank financial performance. Contrary to the existing literature, our results show ATMs have a positive relationship with profitability. However, we find no association between ATMs and growth performance. © 2011 Elsevier B.V. All rights reserved.

Hsiao S.-H.,University of Kang Ning | Pai T.-M.,Nan Hua University | Shih M.-L.,National Taitung University | Su S.-Y.,Nan Hua University
Journal of Convergence Information Technology | Year: 2011

The life insurance industry has pivotal impact on an entire national economy. Under the trend of liberalization and internationalization, operating efficiency is critical to sustainable operations, and cost efficiency improvements positively affect operating efficiency, since integrated utilization of resources can produce maximal economic benefit. This study covers the period from 1997 to 2007, and adopted the Stochastic Cost Frontier Approach (SCFA) to make cost efficiency and economy-of-scale analyses, and studied cost efficiency factors. Some empirical results are as follows: 1) Variable scales and variable patterns in the life insurers enable different economy-of-scale and cost efficiency values. 2) It is recommended to join financial holding company or utilize a horizontal alliance to improve cost efficiency. 3) Based on the Tobit regression analysis, total asset turnover, fixed asset turnover are positively relative to cost efficiency. However, insurance payment to net written premium ratio is negatively relative to cost efficiency.

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