Browsing by Author "Huang, Yi-Hsuan"

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Electrochromic Properties of Tunsgten Trioxide Nanostructures
(2013)
Huang, Yi-Hsuan
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Hung, Chung-Jung
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Tseng, Tseung-Yuen
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
WO3 is the most widely studied electrochromic material because of its high colouration efficiency and high cyclic stability. Use of tungsten hexachloride as precursor synthesizes the highly porous WO3 nanowire networks by hydrothermal method. Color efficiency of 120.3 cm(2) C-1 during the coloration/bleaching process, high transmittance contrast(57%), and short switching time(t(b)=7 s, t(c)=21 s) can be achieved when employing WO3 nanowire networks as electrochromic devices.
Natural convection in an oscillating cylindrical enclosure with pin fins
(2016-02-01)
Hsu, Hao-Ju
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Huang, Yi-Hsuan
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Liu, Yao-Hsien
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機械工程學系
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Department of Mechanical Engineering
This study experimentally investigated natural convection in an oscillating cylindrical enclosure to simulate heat transfer inside a buoy of a wave power generator. Mechanical oscillations were applied vertically to simulate the operating conditions of a wave power generator extracting energy from the surface motion of ocean waves. The Rayleigh numbers used in this study ranged from 50,000 to 600,000. Enclosures of various heights H (2.5, 3, 4, and 5 cm) and oscillations of various frequencies (1 and 2 Hz) were investigated. In addition, pin fins of length L were attached to the heat transfer area, and the heat transfer coefficient variation was examined at various L/H ratios (0.4, 0.33, 0.25, and 0.2). The results indicate that the pin fins enhanced the heat transfer under both stationary and oscillating conditions by up to 30%. The mechanical oscillation did not cause considerable changes in heat transfer based on the tested parameters, and the maximal heat transfer variation was less than 10%. (C) 2015 Elsevier Ltd. All rights reserved.
NON-BOILING HEAT TRANSFER OF AIR/WATER MIST FLOW IN A SQUARE DUCT WITH ORTHOGONAL RIBS
(2016)
Huang, Yi-Hsuan
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Chen, Chiao-Hsin
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Liu, Yao-Hsien
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機械工程學系
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Department of Mechanical Engineering
Heat transfer of mist flow in a rib-roughened square duct was experimentally determined using infrared thermography. The mist flow was generated by introducing fine dispersed water droplets into the air stream. A constant heat flux was applied to the surface during the test and the surface temperature was kept below the boiling point. The heat transfer measurement was performed on a heated surface located inside a vertical square duct with a hydraulic diameter of 4cm. The air/water mist flow was carried upward by air flow from a blower placed at the bottom of the duct. The flow passed through a flow straightener and entered the heated region of the square duct. The Reynolds numbers of the carrier fluid were 7900, 16000 and 24000. The results showed that mist flow cooling achieved higher heat transfer rates compared to the air cooling. Thin liquid films formed on the heated surface by the mist flow and the evaporation from the droplets and liquid film contributed to a higher heat removal rate. The heat transfer enhancement on the smooth surface by the mist flow was 4 to 6 times higher compared to the air flow. Rib turbulators were typically applied in channel walls for heat transfer enhancement in gas turbine blades or heat exchangers. Ribs caused flow reattachment and promoted flow mixing. The higher Nusselt number induced by flow reattachment can be visualized using infrared thermography. For the ribbed case, the heat transfer contours were reported based the regions between ribs. Square brass ribs were used and the rib height-to-hydraulic diameter ratio was 0.05. The rib pitch-to-height ratios were 10 and 20 in the current study. For the mist flow in the ribbed duct, the intense flow mixing and secondary flow caused by the ribs blew away liquid films on the surface. The heat transfer enhancement near the reattachment region was mainly influenced by the droplet impingement on the surface. In the ribbed duct, the heat transfer enhancement from using the mist flow was 2.5 to 3.5 times higher compared to the air flow.
Nonboiling Heat Transfer and Friction of Air/Water Mist Flow in a Square Duct With Orthogonal Ribs
(2017-12-01)
Huang, Yi-Hsuan
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Chen, Chiao-Hsin
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Liu, Yao-Hsien
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機械工程學系
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Department of Mechanical Engineering
Heat transfer of air/water mist flow in a single-side heated vertical duct was experimentally investigated. The mist flow was produced by introducing fine dispersed water droplets into the air stream, and the water-air mass flow ratios were up to 15%. The Reynolds numbers of the air flow were 7900, 16,000, and 24,000. The rib spacing-to-height ratios were 10 and 20 in the current study. Mist flow cooling achieved higher heat transfer rates mainly because of the droplet deposition and liquid film formation on the heated surface. The heat transfer enhancement on the smooth surface by the mist flow was 4-6 times as high as the air flow. On the ribbed surface, a smaller rib spacing of 10 was preferred for air cooling, since the heat transfer enhancement by the flow reattachment was better utilized. However, the rib-induced secondary flow blew away the liquid films on the surface, and the heat transfer enhancement was degraded near the reattachment region for the mist cooling. A larger rib spacing-to-height ratio of 20 thus achieved higher heat transfer because of the liquid film formation beyond the reattachment region. The heat transfer enhancement on the ribbed surface using mist flow was 2.5-3.5 times as high as the air flow. The friction factor of the mist flow was two times as high as the air flow in the ribbed duct.
Ontology-based neural network for patent knowledge management in design collaboration
(2013-04-01)
Trappey, Amy J. C.
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Trappey, Charles V.
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Chiang, Tzu-An
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Huang, Yi-Hsuan
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管理科學系
In order to stimulate innovation during the collaborative process of new product and production development, especially to avoid duplicating existing techniques or infringing upon others' patents and intellectual property rights, the collaborative team of research and development, and patent engineers must accurately identify relevant patent knowledge in a timely manner. This research develops a novel knowledge management approach using ontology-based artificial neural network (ANN) algorithm to automatically classify and search knowledge documents stored in huge online patent corpuses. This research focuses on developing a smart and semantic oriented classification and search from the sources of the most critical and well-structured knowledge publications, i.e. patents, to gain valuable and practical references for the collaborative networks of technology-centric product and production development teams. The research uses the domain ontology schema created using Protege and derives the semantic concept probabilities of key phrases that frequently occur in domain relevant patent documents. Then, by combining the term frequencies and the concept probabilities of key phrases as the ANN inputs, the method shows significant improvement in classification accuracy. In addition, this research provides an advanced semantic-oriented search algorithm to accurately identify related patent documents in the patent knowledge base. The case demonstration analyses 343 chemical mechanical polishing and 150 radio-frequency identification patents sample sets to verify and measure the performance of the proposed approach. The results are compared with the previous automatic classification methods demonstrating much improved outcomes.