Browsing by Issue Date, starting with "2009-06-01"

Now showing 1 - 20 of 50638

Interface effect of oxygen doping in polythiophene
(2009-06-01)
Liu, Chien-Cheng
;
Yang, Chia-Ming
;
Liu, Wen-Hsing
;
Liao, Hua-Hsien
;
Horng, Sheng-Fu
Long-time evolution of the electrical characteristics for two-terminal and transistor of poly(3-hexylthiophene) film with various gate dielectric interfaces are measured. The oxygen doping is found to depend sensitively on the amount of hydroxyl groups of the interface and irreversible after long time in vacuum except for quartz. For a given interface, dip-coated film always has a higher doping level and slower de-doping than spin-coated films because of higher porosity. With careful control of the oxygen level transistor with mobility of 0.12 cm(2)/V s and on-off ratio of 29,000 are obtained for dip-coated film on glass substrate. (C) 2009 Elsevier B.V. All rights reserved.
Experimental study of forced convective boiling for non-azeotropic refrigerant mixtures R-22/R-124 in horizontal smooth tube
(2009-06-01)
Chiou, C. B.
;
Lu, D. C.
;
Liao, C. Y.
;
Su, Y. Y.
;
機械工程學系
In this article, the experiment is carried out with four stages of test section and new experimental data of non-azeotropic refrigerant mixtures R-22/R-124 are presented. Existing correlations are analysed and new ones are proposed for pure refrigerants. The nucleate boiling correlation of the refrigerant mixtures is modified so as to obtain the evaporation heat transfer coefficient of the refrigerant mixtures in a smooth tube. The result shows that the majority of the predictions fall within +/- 30% of the experiments. (c) 2008 Elsevier Ltd. All rights reserved.
Magnetic anisotropy in symmetric magnetic colloidal quantum dots doped with few Mn(2+) impurities
(2009-06-01)
Cheng, Shun-Jen
;
電子物理學系
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Department of Electrophysics
We present numerical exact diagonalization studies of the magnetism in magnetic II-VI colloidal semiconductor quantum dots charged with controlled number of electrons coupled to few magnetic-ion (Mn(2+)) dopants. The interplay between various relevant spin interactions and the discrete nature of Mn(2+) spin distribution is shown to be essential in the magnetism of few Mn(2+)-doped quantum dots. An interesting revealed feature is the existence of pronounced magnetic anisotropies in symmetric magnetic quantum dots, which are related to the orbital quenchings induced by electron-Mn spin interactions. The orbital quenching effects further lead to significant deviations of the magnetizations of randomly Mn-doped dots from the standard Brillouin-function descriptions.
Liquid Crystalline Conjugated Polymers and Their Applications in Organic Electronics
(2009-06-01)
Yang, Sheng-Hsiung
;
Hsu, Chain-Shu
;
應用化學系
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Department of Applied Chemistry
This article describes the syntheses and electro-optical applications of liquid crystalline (LC) conjugated polymers, for example, poly(p-phenylenevinylene), polyfluorene, polythiophene, and other conjugated polymers. The polymerization involves several mechanisms: the Gilch route, Heck coupling, or Knoevenagel condensation for poly(p-phenylenevinylene)s, the Suzukior Yamamoto-coupling reaction for polyfluorenes, and miscellaneous coupling reactions for other conjugated polymers. These LC conjugated polymers are classified into two types: conjugated main chain polymers with long alkyl side chains, namely main-chain type LC polymers, and conjugated polymers grafting with mesogenic side groups, namely side-chain type LC conjugated polymers. In general, the former shows higher transition temperature and only nematic phase: the latter possesses lower transition temperature and more mesophases, for example. smectic and nematic phases, depending on the structure of mesogenic side chains. The fully conjugated main chain promises them as good candidates for polarized electroluminescent or field-effect devices. The polarized emission can be obtained by surface rubbing or thermal annealing in liquid crystalline phase, with maximum dichroic ratio more than 20. In addition, conjugated oligomers with LC properties are also included and discussed in this article. Several oligo-fluorene derivatives show outstanding polarized emission properties and potential use in LCD backlight application. (c) 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47:2713-2733, 2009
The effects of PE additive on the performance of polystyrene vacuum insulation panels
(2009-06-01)
Tseng, P. C.
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Chu, H. S.
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機械工程學系
;
Department of Mechanical Engineering
The effects of adding polyethylene (PE) in polystyrene (PS) foaming material on the cell structure and the heat transfer of vacuum insulation panels (VIPs) are examined in this study. Several parameters are proposed to describe the foam structure, namely, the broken cell ratio, the average cell size and the solid volume fraction. Adding 2% PE was effective in altering the cell structure and reducing the heat transfer, while adding 5% PE did not improve the performance further. The lowest thermal conductivity found in this study is 4.4 mW m(-1) K(-1), which is among the best published performances of VIP. (C) 2009 Elsevier Ltd. All rights reserved.
Optimization of the T policy M/G/1 queue with server breakdowns and general startup times
(2009-06-01)
Wang, Tsung-Yin
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Wang, Kuo-Hsiung
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Pearn, Wen Lea
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工業工程與管理學系
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Department of Industrial Engineering and Management
This paper investigates the T policy M/G/1 queue with server breakdowns, and startup times. Customers arrive at the system according to a Poisson process. Service times, repair times, and startup times are assumed to be generally distributed. The server is turned on after a fixed length of time T repeatedly until at least one customer is present in the waiting line. The server needs a startup time before starting the service. We analyze various system performance measures and develop the total expected cost function per unit time in which T is a decision variable. We determine the optimum threshold T* and derive analytical results for sensitivity investigations. The sensitivity analysis is particularly valuable to the system analyst when evaluating future conditions. We also present extensive numerical computation for illustration purpose. (c) 2008 Elsevier B.V. All rights reserved.
去／再領域化的西門町：「擬東京」消費地景的想像與建構
(國立陽明交通大學出版社, 2009-06-01)
李明璁
本研究藉由對台北西門町消費地景變遷的歷史與民族誌考察，反省並修補晚近全球化理論中相當盛行的「去領域化」概念。本文主張：去領域化不該是「無國界」或「除地域性」的簡單想像，所有去領域都必然伴隨著再領域化。去／再領域化的歷史不是單線性發展，而是辯證的推拉過程。本文解釋了不同時期在西門町的居住／行動者（日本殖民者、戰後中國移民、晚近台北青少年等），如何透過挪用或模擬遠方異地的消費素材，以實踐他們的文化想像計畫。此外，本文亦進一步以經常報導西門町的Taipei Walker-來自日本、卻生產在地消費情報的雜誌為案例，說明這個跨文化的消費鍊結與想像社群如何形成。由此，西門町的地景宛若一張羊皮紙，既更迭抹除、卻又沈積堆疊著日本殖民現代性、國府發展主義邏輯、以及在地／跨國聯結的青年次文化等遺緒，從而建構出如今我們所見：台日文化交混雜揉的「擬東京」消費地景。
Transient-Induced Latchup in CMOS ICs Under Electrical Fast-Transient Test
(2009-06-01)
Yen, Cheng-Cheng
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Ker, Ming-Dou
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Chen, Tung-Yang
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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
The occurrence of transient-induced latchup (TLU) in CMOS integrated circuits (10) under electrical fast-transient (EFT) tests is studied. The test chip with the parasitic silicon-controlled-rectifier (SCR) structure fabricated by a 0.18-mu m CMOS process was used in EFT tests. For physical mechanism characterization, the specific "swept-back" current caused by the minority carriers stored within the parasitic PNPN structure of CMOS ICs is the major cause of TLU under EFT tests. Different types of board-level noise filter networks are evaluated to find their effectiveness for improving the immunity of CMOS ICs against TLU under EFT tests. By choosing the proper components in each noise filter network, the TLU immunity of CMOS ICs against EFT tests can be greatly improved.
Modeling heat extraction from hot dry rock in a multi-well system
(2009-06-01)
Yang, Shaw-Yang
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Yeh, Hund-Der
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環境工程研究所
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Institute of Environmental Engineering
A mathematical model is developed for describing the heat energy extracted from a hot dry rock in a multi-well system. The solutions for the water temperature, accounting for a geothermal gradient in a geothermal reservoir, are given in the Laplace domain and computed by numerical inversion, the modified Crump method. The results show that the heat extraction effectiveness is affected significantly by the well spacing, well radius, reservoir thickness, and pumped flow rate in a multi-well system. The water temperature decreases with increasing pumping rate and increases with the well spacing, well radius, and reservoir thickness. The geothermal gradient affects only the early time heat extraction effectiveness significantly and has direct impact on the water temperature all the time if the vertical thickness of geothermal reservoir is large. The present solution is useful for designing and simulating the heat extraction project of geothermal energy exploitation in a multi-well system. (C) 2008 Elsevier Ltd. All rights reserved.
檔案夢：從《最好的時光》之〈戀愛夢〉中的一個音樂錯置論德希達的檔案熱
(國立陽明交通大學出版社, 2009-06-01)
林克明
當導演以他自己的故事為電影題材時，他的電影究竟喚起他何種記憶呢？本文從《最好的時光》這部電影中的一個音樂錯置問題出發，嘗試從德希達的「檔案熱」來理解電影與記憶的關係：透過德希達對檔案的觀點，電影所召喚的記憶絕非所謂的「真實資料」，而是潛藏在真實資料背後、不可見的「陰影檔案」。而從德希達對「夢的邏輯」的詮釋，本文亦試圖指出唯有當電影成為創作者的夢，創作者才能成功召喚他所期待的記憶。
不只地景像羊皮紙，論文也是
(國立陽明交通大學出版社, 2009-06-01)
李明璁
Formation and degradation mechanism of a novel nanofibrous polyaniline
(2009-06-01)
Ho, Ko-Shan
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Han, Yu-Kai
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Tuan, Yu-Tsung
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Huang, Ying-Jie
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Wang, Yen-Zen
A nanotubular, nanofibrous polyaniline (PANINT) was prepared from an emulsion polymerization in the presence of n-dodecylbenzene sulfonic (DBSA) and hydrochloric acids. The building of the tubular structure based on the tubular micelles from the accumulation (pile up) of micelles at high surfactant concentration, leading to early stage of centipede-like and eventual tubular morphologies. The PANINT molecule owning a highly conjugated backbone demonstrated a free carrier-tail in the near-IR region due to its helical conformation. After dedoping, the once empty PANINT with only some complexed DBSA inside shrank into solid rods, after the removal of the complexed DBSA. As a result, the solid rods were filled with helical emeradine base (nano-EB) molecules associated with inter-molecular H-bonding. The solid rods of nano-EB went on crosslinking and carbonization after 200-300 degrees C by opening the quinoid rings and the inter-molecular H-bondings were destroyed with nano-EB molecules crosslinking into ladder-like structure. When temperature was over 300 degrees C and below 800 degrees C, carbonization enhanced by de-ammoniaization, causing a significant weight loss. However, the cleavage of aromatic rings into aliphatic pieces occurred after 800 degrees C, which chopped the ladder-like, strips of carbonized nano-EB sheets into small pieces of nano-particles. The conductivity of the pyrolyzed nano-EB was found to be around 10(-5) s/cm, 10,000 times higher than the neat nano-EB of 10(-9) s/cm due to the carbonization. (C) 2009 Elsevier B.V. All rights reserved.
Novel face-detection method under various environments
(2009-06-01)
Jing, Min-Quan
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Chen, Ling-Hwei
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資訊工程學系
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Department of Computer Science
We propose a method to detect a face with different poses under various environments. On the basis of skin color information, skin regions are first extracted from an input image. Next, the shoulder part is cut out by using shape information and the head part is then identified as a face candidate. For a face candidate, a set of geometric features is applied to determine if it is a profile face. If not, then a set of eyelike rectangles extracted from the face candidate and the lighting distribution are used to determine if the face candidate is a nonprofile face. Experimental results show that the proposed method is robust under a wide range of lighting conditions, different poses, and races. The detection rate for the HHI face database is 93.68%. For the Champion face database, the detection rate is 95.15%. (C) 2009 Society of Photo-Optical Instrumentation Engineers. [DOI: 10.1117/1.3156843]
Lake Level Variations Monitored With Satellite Altimetry Waveform Retracking
(2009-06-01)
Guo, Jinyun
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Chang, Xiaotao
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Gao, Yonggang
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Sun, Jialong
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Hwang, Cheinway
Over lake shores, altimetric waveforms are generally contaminated by lands, rough lake surfaces, and lag effects of the altimeter's automatic gain control. To improve altimeter ranging accuracy and in turn to get better surface height measurement, contaminated waveforms should be retracked against geophysical corrections. In this paper, an improved threshold retracker (ITR) is developed to retrack waveforms over lakes. ITR considers not only the physical characteristics of the reflecting surface, but also the stochastic feature of waveform, and two new retrackers, the N-Beta function model, and the N-5-Beta function model, are also put forward to develop the waveform retracking program of this study. TOPEX/POSEIDON waveforms over Hulun Lake in the North China are retracked to monitor the temporal lake level variations. A comparison with the in situ hydrological data indicates ITR is very efficient to monitor the lake level variations with the retracked altimetric data. The result of our study shows accurate seasonal level variations and the descending trend of Hulun Lake.
Homogeneous Nucleation of Epitaxial CoSi(2) and NiSi in Si Nanowires
(2009-06-01)
Chou, Yi-Chia
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Wu, Wen-Wei
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Chen, Lih-Juann
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Tu, King-Ning
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材料科學與工程學系
Homogeneous nucleation is rare except in theory. We observed repeating events of homogeneous nucleation in epitaxial growth of CoSi(2) and NiSi silicides in nanowires of silicon by using high resolution TEM. The growth of every single atomic layer requires nucleation. Heterogeneous nucleation is prevented because of non-microreversibility between the oxide/Si and oxide/silicide interfaces. We determined the incubation time of homogeneous nucleation. The calculated and the measured nucleation rates are in good agreement. We used Zeldovich factor to estimate the number of molecules in the critical nucleus; it is about 10 and reasonable. A very high supersaturation is found for the homogeneous nucleation.
最個人的也就是最政治的：訪陳界仁
(國立陽明交通大學出版社, 2009-06-01)
林志明
;
陳美璇
從詩語革命到電影詩學：論俄國未來主義和形式主義的視覺性
(國立陽明交通大學出版社, 2009-06-01)
張歷君
在文學理論的研究領域裡，俄國形式主義通常都被視為以科學方法處理文學內在問題的倡導者。他們為文學研究樹立了新紀律，主張文學研究必須以文學本身為目標，必須是一種獨立自主的活動，而不是其他學科的附庸。與主流學界所呈現的上述形象恰恰相反，本研究發現，俄國形式主義者對「文學性」的理解和定義，其實與20世紀初新興的電影影像邏輯和立體未來主義的視覺實驗，有著緊密的歷史因緣。因此，本文嘗試透過大量的史料鉤沈和文本分析，將俄國形式主義的理論觀點重新置放在立體未來主義和構成主義等蘇俄左翼前衛藝術運動的語境中，進行再解讀；希望藉此點明，俄國形式主義在文學研究領域裡所推動的範式轉移運動，與蘇俄左翼前衛藝術工作者在電影和繪畫等視覺藝術領域所進行的實驗創作之間的歷史轇轕。最終，本文希望初步闡明，包含在俄國形式主義文學理論中獨特的視覺經驗或視覺性；並在結語部分進一步指出，隱含在蘇俄左翼前衛藝術理論和實踐中的文化政治意涵。
「空缺主體」與「陰性情境」：重探台灣後殖民論述的幾個面向
(國立陽明交通大學出版社, 2009-06-01)
張君玫
自從1990年代幾場關於台灣後殖民性的激辯，「後殖民」已成為台灣文學批判與史論的重要部分。然而，關於台灣後殖民主體性的深入討論，卻往往因政治立場而中斷。本文擬從幾個面向重探台灣的後殖民論述場域。首先，我將檢視相關論述中頻見的「女性喻說」，並從身體現象學的取向進一步釐清身體／土地的物質性與能動力，以期理解台灣後殖民主體性的「陰性情境」。接著，我將重訪邱貴芬、廖朝陽和廖咸浩等學者在十多年前的辯論，接續他們的腳步，追索若干關鍵的爭議點，尤其是關於「主體位置」、「空白主體」與「主體化」等概念之間的複雜動態。最後，我將試圖以「陰性情境」和「空缺主體」之間的相互闡連來理解台灣的主體性空間，以及如何在關於認同建構的文化研究中重新置入土地與肉身的物質性思考。
A mechanism for the formation of annealed compact oxide layers at the interface between anodic titania nanotube arrays and Ti foil
(2009-06-01)
Chen, Chien-Chon
;
Say, Wen C.
;
Hsieh, Sheng-Jen
;
Diau, Eric Wei-Guang
;
應用化學系
We propose a mechanism for the growth of crystalline anodic titanium-oxide (ATO) nanochannel arrays based on thermodynamic considerations and structural imperfections. Both amorphous and crystalline ATO films were obtained from the anodization of a titanium foil. Amorphous ATO nanotubes have a single-layer form, which makes them inefficient for use in photo-catalytic and solar-cell applications. Annealed ATO nanotubes are considered non-stoichiometric if the effect of oxygen partial pressure on the composition is significant. The driving force behind growing crystalline ATO nanotubes is the drawing of oxygen from the atmosphere to the oxygen site, which consequently decreases the concentration of oxygen vacancies in the anatase phase. The small ionization energies of titanium ions produce the stoichiometric defects. A diagram showing Gibbs energy and Kroger-Vink notation to indicate the strong influence of the non-stoichiometric ATO structure is deduced.
Simultaneously gain-flattened and gain-clamped erbium fiber amplifier
(2009-06-01)
Yeh, C. H.
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Huang, T. T.
;
Lin, M. C.
;
Chow, C. W.
;
Chi, S.
In this paper, we propose and demonstrate a simple erbium amplifier module based on an erbium-doped fiber amplifier (EDFA) and an erbium-doped waveguide amplifier (EDWA) in serial, having gain-flatted (GF) and gain-clamped (GC) functions simultaneously. In first proposed GF amplifier scheme, the maximum gain variation of 2.5 dB can be observed in the effective range of 1528 to 1562 nm and the entire gains are above 35 dB with the input signal power of -30 dBm. Hence, we investigate second scheme by optical feedback method in the proposed fiber amplifier achieving gain-flattened (GF) and gain-clamped (GC) efficiencies simultaneously. Thus, the maximum gain variations of +/- 0.8 and +/- 1.8 dB can be obtained in the operating range of 1530 to 1564 nm, when the input signal powers are -16 and -40 dBm, respectively. Moreover, the dynamic gain profile can be adjusted and dynamic input power range is also measured based on the proposed GF and GC fiber amplifier.