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Tainan, Taiwan

The National University of Tainan is a university in East District, Tainan, Taiwan. Wikipedia.

Yeh C.-T.,National University of Tainan
Fuzzy Sets and Systems

Recently, many scholars investigated interval, triangular, and trapezoidal approximations of fuzzy numbers. These publications can be grouped into two classes: Euclidean distance class and non-Euclidean distance class. Most approximations in Euclidean distance class can be calculated by formulas, but calculating approximations in the other class is more complicated. In the present paper, we study a special class of non-linear approximations with respect to a weighted Euclidean distance. We call it "weighted semi-trapezoidal approximations". The proposed approximations generalize all recent approximations in Euclidean distance class. First, we embed fuzzy numbers into a Hilbert space. Then compute weighted semi-trapezoidal approximations by means of best approximations in a closed convex subset of the Hilbert space. Finally, we propose formulas of matrix type, which is more clear than the previous contributions. © 2010 Elsevier B.V. All rights reserved. Source

Hwang J.J.,National University of Tainan
Renewable and Sustainable Energy Reviews

In 2008, Taiwan government passed a set of rules designed to achieve a sizable reduction of carbon dioxide (CO 2) emissions, namely, "Frameworks of Sustainable Energy Policy". The target of the policy is to keep CO 2 emissions during the 2016-2020 periods at the 2008 level, to reduce them to the 2000 level in 2025, and to cut that level in half by 2050. Currently, the acts of "Statute for Renewable Energy Development" and "Energy Management Act (amendment)" is being implemented while those of "Greenhouse Gas (GHG) Reduction Act (draft)" and "Regulation for Energy Tax (draft)" is being scheduled for legislative reviewing. These acts deal with GHG emission reduction via various policy instruments such as cap and trade, subsidies, and taxes. The present paper presents a detailed review of the policy progress of GHG emission reduction in Taiwan in addition to the assessment of the outcome of GHG emission reduction in the past decade. It also proposed the priority of policy implementation of GHG emission reduction in the country in the post-Kyoto era. © 2010 Published by Elsevier Ltd. Source

Hwang J.-J.,National University of Tainan
Journal of Power Sources

The objective of the present paper is to conduct an experimental work to measure transient thermal/electrical efficiencies in a combined heat and power (CHP) fuel cell generator. An original-designed fuel cell CHP generator comprising a proton exchange membrane (PEM) fuel cell system, a power conditioning system, and a thermal recovery system is constructed. The thermal recovery system recaptures the thermal energy dissipated by the fuel cell stack, while the power conditioning system distributes the electrical power of the fuel cell system. Performance matrices including stack electrical efficiency, system electrical efficiency, thermal efficiency, and CHP efficiency are presented. Particular attention is placed on the variation of transient system efficiencies as the load is changed drastically. The time-averaged system efficiency is then concluded from the statistics of the transient system efficiency. Results show that the time-averaged efficiencies in electrical, thermal and CHP are about 37%, 24%, and 61%, respectively, under 55% electrical power capacity of the generator. The instantaneous CHP efficiency could reach as high as 85% in the loading period. © 2012 Elsevier B.V. All rights reserved. Source

Hsu C.-L.,National University of Tainan | Chang S.-J.,National Cheng Kung University

In the past decades, the doping of ZnO one-dimensional nanostructures has attracted a great deal of attention due to the variety of possible morphologies, large surface-to-volume ratios, simple and low cost processing, and excellent physical properties for fabricating highperformance electronic, magnetic, and optoelectronic devices. This article mainly concentrates on recent advances regarding the doping of ZnO one-dimensional nanostructures, including a brief overview of the vapor phase transport method and hydrothermal method, as well as the fabrication process for photodetectors. The dopant elements include B, Al, Ga, In, N, P, As, Sb, Ag, Cu, Ti, Na, K, Li, La, C, F, Cl, H, Mg, Mn, S, and Sn. The various dopants which act as acceptors or donors to realize either p-type or n-type are discussed. Doping to alter optical properties is also considered. Lastly, the perspectives and future research outlook of doped ZnO nanostructures are summarized. © 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Hwang J.J.,National University of Tainan
Renewable and Sustainable Energy Reviews

The current development of fuel cell scooters has been reviewed in this paper. Fuel cell scooters, by nature, have zero emissions, and they have the potential to replace current petroleum-propelled engine scooters. First, the fundamentals of fuel cells, including the critical technologies pertaining to fuel cell engines and hydrogen storage, were introduced. Then, the technical feasibility of fuel cell scooters was discussed in parallel with the hydrogen infrastructure model. The accomplishments of fuel cell scooters in Taiwan were presented. Moreover, the contribution of replacing petrol scooters by hydrogen fuel cell scooters to reduction in greenhouse gas (GHG) emission and energy conservation was evaluated. Furthermore, industrial competition with regard to the development of fuel cell scooters was discussed on the basis of a strengths, weaknesses, opportunities, and threats (SWOT) analysis. In conclusion, with mature fuel cell technology together with solid foundation of the scooter industry, Taiwan offers conditions that were conducive for the development of fuel cell scooters. Its social and technical capability will be proved on account of the leading demonstrations of fuel cell scooters in the world. If it can develop a successful business model, Taiwan could enjoy the advantages of tapping the huge global market for zero-emission scooters. © 2012 Elsevier Ltd. All right reserved. Source

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