Browsing by Issue Date, starting with "2009-09-21"

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交大e-News第056期
(2009-09-21)
Secretariat
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國立交通大學秘書室
Voltage-tunable two-color quantum-dot infrared photodetectors
(2009-09-21)
Lin, Shih-Yen
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Lin, Wei-Hsun
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Tseng, Chi-Che
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Chao, Kuang-Ping
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Mai, Shu-Cheng
A two-terminal quantum-dot infrared photodetector with stacked five-period InAs/GaAs and InGaAs-capped InAs/GaAs quantum-dot (QD) structures is investigated. The device has exhibited distinct responses at mid-wavelength and long-wavelength infrared regions under positive and negative biases, respectively. The results suggest that the QD confinement states near the anode side are completely filled, such that selective responses at different wavelength ranges would be observed for the stacked structure under different voltage polarities. Also observed are the similar absorption ratios of the device under different incident light polarizations at the two response regions. (C) 2009 American Institute of Physics. [doi: 10.1063/1.3236543]
Wave properties of an annular periodic multilayer structure containing the single-negative materials
(2009-09-21)
Chen, Mei-Soong
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Wu, Chien-Jang
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Yang, Tzong-Jer
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電子物理學系
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Department of Electrophysics
The optical properties of an annular periodic multilayer structure containing two kinds of single-negative materials are theoretically investigated based on the transfer matrix method of the cylindrical waves. At the azimuthal mode number m >= 1 and near the magnetic plasma frequency and the electronic plasma frequency for the TE wave and TM wave, respectively. we find that there is an additional high-reflectance band and some reflection dips exist when the plasma frequency is located in the photonic band gap. These two special features arising from the higher order azimuthal mode of the cylindrical waves are not seen in the planar one-dimensional Bragg reflector consisting of the single-negative materials. Such filtering responses provide a feasible way of designing a narrowband resonator without physically introducing any defect layer in the structure. (C) 2009 Elsevier B.V. All rights reserved.
An Unprecedentedly Huge Square-Grid Copper(II)-Organic Framework Material Built from a Bulky Pyrene-Derived Elongated Cross-Shaped Scaffold
(2009-09-21)
Tsai, Chen-Chuan
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Luo, Tzuoo-Tsair
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Yin, Jen-Fu
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Lin, Hong-Cheu
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Lu, Kuang-Lieh
A new bulky pyrene-derived elongated cross-shaped organic scaffold was successfully incorporated into a highly porous, non-interpenetrated square-grid copper(II)-organic framework material with the unprecedentedly huge dimensions of 25.5 x 25.5 angstrom(2), while the layer-to-layer NH center dot center dot center dot N interaction leads to a unique hydrogen-bonded 6(4).8(2)-nbo net.
Application of secondary electron potential contrast on junction leakage isolation
(2009-09-21)
Liu, Po-Tsun
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Lee, Jeng-Han
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Huan, Y. S.
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Su, David
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光電工程學系
Secondary electron potential contrast (SEPC) technology with an in situ dynamic trigger was studied to inspect P(+)/N-well junction leakage arising from P-well misalignment in a static random access memory cell. Combining SEPC with scanning electron microscopy observations allows direct identification of the junction shift. Furthermore, an in situ negative bias applied to the P-well can create a wider depletion region and eliminate the leakage path in P(+)/N-well contacts, allowing the P(+)/N well to operate normally. This proposed in situ dynamic trigger method is a promising and effective approach to investigating device physics under a dynamic scope. (C) 2009 American Institute of Physics. [doi:10.1063/1.3233963]
Structural and optical properties of buried InAs/GaAs quantum dots on GaAsSb buffer layer
(2009-09-21)
Wu, Y. H.
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Chang, Li
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Lin, P. Y.
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Chiang, C. H.
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Chen, J. F.
In this work, we investigated the effect of a 1 nm thick GaAs(94.3)Sb(0.57) buffer layer on structural and optical properties of buried InAs quantum dots (QDs) and wetting layers (WLs) in GaAs using photoluminescence (PL) and transmission electron microscopy (TEM). The density and emission wavelength of the QDs on the buffer were increased due to the size and the shape modification in comparison with those without a buffer. PL analysis of the ground-state (GS) peak of the QDs on the buffer showed a red-shift of 18 meV with an enhanced intensity. In addition, PL and TEM show that the buffer has a weak effect on the WLs and no apparent changes occur for the buffer during QD deposition and the capping process.
Synthesis of Photoisomerizable Block Copolymers by Atom Transfer Radical Polymerization
(2009-09-22)
Huang, Chih-Feng
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Chen, Wei
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Russell, Thomas P.
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Balazs, Anna C.
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Chang, Feng-Chih
A series of polystyrene-block-poly(n-butyl methacrylate) (PS-b-PnBMA) diblock copolymers (di-BCPs) with an azobenzene moiety [trans-4-methacryloyloxyazobenzene (MOAB)] in the PnBMA segment was prepared by atom transfer radical polymerization (ATRP). P(nBMA-co-MOAB) macroinitiators were prepared by activators regenerated by electron transfer (ARGET) ATRP. The MOAB was slightly more reactive than nBMA, resulting in a weak gradient fashion of copolymer. The macroinitiators were subsequently chain-extended with styrene. Acceleration of the ATRP rate was observed in the presence of a reducing agent. P(nBMA-co-MOAB)-b-PS di-BCPs were obtained with relatively narrow molecular weight distributions ((M) over bar (w)(M) over bar (n) = 1.16-1.49) and the molecular weights were in good agreement with the theoretical values. The efficiency of photoisomerization of the MOAB units was above 80%. DSC traces showed a single T(g) suggesting the block copolymers were miscible before UV irradiation. After UV irradiation, the X-ray reflectivity measurements showed the beating of two frequencies, indicating the formation of island-hole structure.
Method for modulating refractive indices of optical fiber gratings
(2009-09-22)
Hsu
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Kuei Chu
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Lai
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Yin Chieh
The present invention proposes a method for modulating refractive indices of optical fiber gratings, wherein the UV exposure on a least one assigned location of an optical fiber grating is divided into to two UV shots, and the intensities or phases of the two UV shots, which expose the location sequentially, are controlled to make the total exposure intensity of one assigned location maintained at a fixed value, whereby the interference fringes, which are created by a superposition of the two UV shots, have fixed phases and adjustable intensities, and whereby the dc index of the optical fiber grating maintains fixed and the ac index independently adjustable.
一個全人的大學教育經驗：服務學習
(2009-09-23)
程萬里
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開放教育推動中心
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Open Education Office
課程日期： 2009年09月23日(三) 演講人：中原大學程萬里內容摘要：程萬里校長先以探討大學教育的內涵作為開端，引用了數位先哲對於教育的見解，將大學教育與全人教育作連結。大學生應該期待在大學生涯中，能夠得到教學、研究與服務的經驗。內容：影音實況影音(*.flv檔)
Compact single-to-balanced bandpass filter
(2009-09-24)
Chung, Shyh-Jong
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Chen, Kun-Tzu
A compact single-to-balanced bandpass filter is proposed in this invention. Firstly, a pre-design circuit is presented, which is composed of an inductive coupled-line (ICL) bandpass filter and an out-of-phase capacitive coupled-line (CCL) bandpass filter. A novel compact circuit with three coupled lines configuration, derived from the pre-design circuit, is then proposed for miniaturizing the single-to-balanced bandpass filter. In order to verify the feasibility of the proposed structure, a 2.4 GHz multilayer ceramic chip type single-to-balanced bandpass filter with size of 2.0 mm×1.2 mm×0.7 mm is developed. The filter is designed by using circuit simulation as well as full-wave electromagnetic (EM) simulation softwares, and fabricated by the use of low-temperature co-fire ceramic (LTCC) technology. The measured results agree quite well with the simulated. According to the measurement results, the maximum insertion loss is 1.65 dB, the maximum in-band phase imbalance is within 3 degrees, and the maximum in-band magnitude imbalance is less than 0.32 dB.
LEAPING ITERATIVE COMPOSITION METHOD OF COMPLICATED GRAPHIC AND STORAGE MEDIUM HAVING COMPUTER PROGRAM EXECUTING THE SAME
(2009-09-24)
CHEN, Ming-Jang
A leaping iterative composition method of a complicated graphic and a storage medium having a computer program executing the same are described. First, an initiator and generators are set. After several times of iterating, a transitional object is formed. Then, a leaping recursion is performed based on this transitional object. When performing the leaping recursion, a generator of each of the iterations is designed by a single pattern converted from a structural result of a previous iteration added with a base object. Since the result of each of the iterations keeps the original structure, the structure is used as the input initiator. The initiator of the first iteration can be a feature of different iteration objects. Since the input structure of iterations are the same, the advantage of reducing computing resources and avoid system overload are reachable.
Structure, Mechanistic Action, and Essential Residues of a GH-64 Enzyme, Laminaripentaose-producing beta-1,3-Glucanase
(2009-09-25)
Wu, Hsin-Mao
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Liu, Sheng-Wen
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Hsu, Ming-Tsung
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Hung, Chiu-Lien
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Lai, Chun-Chieh
Laminaripentaose-producing beta-1,3-glucanase (LPHase), a member of glycoside hydrolase family 64, cleaves a long-chain polysaccharide beta-1,3-glucan into specific pentasaccharide oligomers. The crystal structure of LPHase from Streptomyces matensis DIC-108 was solved to 1.62 angstrom resolution using multiple-wavelength anomalous dispersion methods. The LPHase structure reveals a novel crescent-like fold; it consists of a barrel domain and a mixed (alpha/beta) domain, forming a wide-open groove between the two domains. The liganded crystal structure was also solved to 1.80 angstrom, showing limited conformational changes. Within the wide groove, a laminaritetraose molecule is found to sit in an electronegatively charged central region and is proximal to several conserved residues including two carboxylates (Glu(154) and Asp(170)) and four other sugar-binding residues (Thr156, Asn(158), Trp(163), and Thr(167)). Molecular modeling using a laminarihexaose as a substrate suggests roles for Glu(154) and Asp(170) as acid and base catalysts, respectively, whereas the side chains of Thr(156), Asn(158), and Trp(163) demarcate subsite +5. Site-directed mutagenesis of Glu(154) and Asp(170) confirms that both carboxylates are essential for catalysis. Together, our results suggest that LPHase uses a direct displacement mechanism involving Glu(154) and Asp(170) to cleave a beta-1,3-glucan into specific alpha-pentasaccharide oligomers.
你的心，聽得見我嗎？
(2009-09-27)
許庭瑜
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Department of Communication and Technology
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傳播與科技學系
隨著聽傲的結束，聽說這部電影也真著水漲船高，2009年在台北舉辦的聽障奧運對我們來說是一個多麼大的光環，但是在這些虛榮之中，我們有真的去傾聽聽障朋友們的聲音嗎？讓聽說用另外一種角度帶你去了解這些聽障朋友們。
新手上路
(2009-09-27)
張雅晴
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Department of Communication and Technology
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傳播與科技學系
新手上路
98新手上路
(2009-09-27)
徐瑩峰
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Department of Communication and Technology
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傳播與科技學系
針對新學期電子報課程的期待，以及對版面字體的小小建議。
《熱帶魚》　夢想與現實的距離
(2009-09-27)
陳怡儒
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Department of Communication and Technology
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傳播與科技學系
簡介電影《熱帶魚》，評論電影裡探討的議題。
自由寫手　放牛班生命故事
(2009-09-27)
林穎瑄
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Department of Communication and Technology
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傳播與科技學系
一群被世人遺棄的劣等生，在閱讀與日記裡頭重新找回自己，再次看見這世界。
喀報觀後小感想
(2009-09-27)
林穎瑄
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Department of Communication and Technology
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傳播與科技學系
喀報觀後小感想
迷惘大學生　未來在哪裡？
(2009-09-27)
陳柏臻
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Department of Communication and Technology
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傳播與科技學系
關於大學生的心態與未來思考
三年後　陶喆69樂章再出發
(2009-09-27)
葉東瑜
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Department of Communication and Technology
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傳播與科技學系
睽違三年，陶喆再度發片，新專輯是否能有所突破？