Browsing by Issue Date, starting with "2012-01-02"

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Ultrafast coherent dynamics of nonadiabatically coupled quasi-degenerate excited states in molecules: Population and vibrational coherence transfers
(2012-01-02)
Mineo, H.
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Kanno, M.
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Kono, H.
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Chao, S. D.
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Lin, S. H.
Results of a theoretical study of ultrafast coherent dynamics of nonadiabatically coupled quasi-degenerate pi-electronic excited states of molecules were presented. Analytical expressions for temporal behaviors of population and vibrational coherence were derived using a simplified model to clarify the quantum mechanical interferences between the two coherently excited electronic states, which appeared in the nuclear wavepacket simulations [M. Kanno, H. Kono, Y. Fujimura, S. H. Lin, Phys. Rev. Lett 104 (2010) 108302]. The photon-polarization direction of the linearly polarized laser, which controls the populations of the two quasi-degenerate electronic states, determines constructive or destructive interference. Features of the vibrational coherence transfer between the two coupled quasi-electronic states through nonadiabatic couplings are also presented. Information on both the transition frequency and nonadiabatic coupling matrix element between the two states can be obtained by analyzing signals of two kinds of quantum beats before and after transfer through nonadiabatic coupling. (C) 2011 Elsevier B. V. All rights reserved.
Chemical Synthesis of the Englerins
(2012-01-02)
Pouwer, Rebecca H.
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Richard, Jean-Alexandre
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Tseng, Chih-Chung
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Chen, David Y. -K.
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應用化學系
In the long lasting battle against cancer, Nature sometimes gives a helping hand to researchers to find new drugs for the treatment of diseases and improvement of patients' well-being. Englerin A has emerged as a promising anticancer candidate as well as being an exciting synthetic challenge for organic chemists. This focus review summarizes the total syntheses reported to date and the synthetic approaches toward analogues of this fascinating natural product.
Efficiency enhancement of silicon solar cells using a nano-scale honeycomb broadband anti-reflection structure
(2012-01-02)
Huang, C. K.
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Sun, K. W.
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Chang, W-L.
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應用化學系
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Department of Applied Chemistry
This experiment demonstrates the process for manufacturing a ZnO honeycomb sub-wavelength structure using nanosphere lithography technology exhibiting excellent anti-reflection properties from the UV to NIR wavelength regions. This honeycomb nanostructure, combined with commercially available crystalline Si solar cells, show substantially improved conversion efficiency from 15.6% to 16.6% using optimized honeycomb sizes and precursor concentrations of ZnO. The present work develops an unsophisticated and economical technique suitable for industrial applications in producing a uniform and low-reflective texture. (C)2011 Optical Society of America
2 x 2 MIMO radio-over-fiber system at 60 GHz employing frequency domain equalization
(2012-01-02)
Lin, Chun-Ting
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Ng'oma, Anthony
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Lee, Wei-Yuan
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Wei, Chia-Chien
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Wang, Chih-Yun
This work experimentally demonstrates the efficacy of the 2 x 2 multiple-input multiple-output (MIMO) technique for capacity improvement of a 60-GHz radio-over-fiber (RoF) system employing single-carrier modulation format. We employ frequency domain equalization (FDE) to estimate the channel response, including frequency response of the 60 GHz RoF system and the MIMO wireless channel. Using FDE and MIMO techniques, we experimentally demonstrate the doubling the of wireless data capacity of a 60 GHz RoF system to 27.15 Gb/s using 16-QAM modulation format, with transmission over 25 km of standard single-mode fiber and 3 m wireless distance. (C) 2011 Optical Society of America
Extended spectral response in organic photomultiple photodetectors using multiple near-infrared dopants
(2012-01-02)
Chuang, Shao-Tang
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Chien, Shang-Chieh
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Chen, Fang-Chung
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光電工程學系
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顯示科技研究所
We demonstrate highly sensitive polymer photodetectors (OPDs) with spectral response extending from the ultraviolet to the near-infrared (NIR) region (similar to 1200 nm). After doping two NIR dopants, high external quantum efficiencies (similar to 5500%) and high responsivities (23.0 A/W) are achieved under a low reverse bias (-3.7 V). The high gains could be attributed to unbalanced carrier transport in the photoactive layer arising from the electron traps at the NIR dopants. This approach allows the ready preparation of OPDs exhibiting broad spectral responses and high quantum efficiencies simultaneously. (C) 2012 American Institute of Physics. [doi:10.1063/1.3675573]
Wireless communication receiving system and apparatus and method for deciding a transmitted signal corresponding to a received signal thereof
(2012-01-03)
Wu Wen-Rong
;
Wu Jiun-Ying
A wireless communication receiving system and an apparatus and a method for deciding a transmitted signal corresponding to a received signal thereof are provided. The transmitted signal comprises a plurality of sub-transmitted signals. The system selects at least one of the sub-transmitted signals as a reference signal group, wherein each of a plurality of candidate values of the reference signal group forms a candidate geometric space respectively. The received signal is projected to each of the candidate geometric spaces to generate a projection signal respectively. In each of the candidate geometric space, the corresponding projection signal is quantized to generate a quantized projection signal having a projection distance to the corresponding projection signal. Finally, the transmitted signal is decided according the quantized projection signal and the candidate signal value corresponding to the shortest projection distance.
Displacement measurement system and method thereof
(2012-01-03)
Hsu Kuei-Chu
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Chen Chii-Chang
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Chan Chia-Hua
;
Lai Yin-Chieh
A displacement measurement system including a coherent light source, a two-dimensional grating, a photo sensor, and a signal processing apparatus is provided. After the coherent light beam enters the two-dimensional grating, a zero-order light beam and a plurality of first-order diffraction beams are generated. The zero-order light beam interferes with two of the first-order beams in different directions, so that corresponding interference fringes are formed on the photo sensor. Accordingly, when the two-dimensional grating moves, displacements of the two-dimensional grating in the different directions are obtained by calculating phase differences of the interference fringes in the corresponding directions. Besides, when the two-dimensional grating rotates, the rotational angle of the two-dimensional grating is obtained from the corresponding rotational angle of a diffraction pattern of the first-order diffraction beams.
Power monitoring device for identifying state of electric appliance and power monitoring method thereof
(2012-01-04)
Tsao, Shiao-Li
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Lai, Yi-Sheng
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Lin, Ming-Chun
;
Chen, Yung-Chi
A power monitoring device for identifying the state of an electric appliance based on user feedbacks and a power monitoring method thereof are provided. The power monitoring device includes a measurement module, a variation detection and search module, and an electric appliance signature database established based on user feedbacks. When the measurement module detects a variation of a power consumption feature, the variation detection and search module searches the electric appliance signature database according to the variation to obtain electric appliances similar to the variation and the states thereof. A user contributes data to the electric appliance signature database by confirming the search result, or selecting the correct electric appliance and the state thereof. When the user confirms the search result, the power monitoring device establishes an association between the electric appliance and its electric appliance signatures and updates the electric appliance signature database.
New Low Bandgap Conjugated Polymer Derived from 2, 7-Carbazole and 5, 6-Bis(octyloxy)-4, 7-di(thiophen-2-yl) Benzothiadiazole: Synthesis and Photovoltaic Properties
(2012-01-05)
Ding, Ping
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Chu, Cheng-Che
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Zou, Yingping
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Xiao, Dequan
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Pan, Chunyue
To develop conjugated polymers with low bandgap, deep HOMO level, and good solubility, a new conjugated alternating copolymer PC-DODTBT based on N-9'-heptadecanyl-2,7-carbazole and 5, 6-bis(octyloxy)-4,7di(thiophen-2-yl) benzothiadiazole was synthesized by Suzuki cross-coupling polymerization reaction. The polymer reveals excellent solubility and thermal stability with the decomposition temperature (5% weight loss) of 327 degrees C. The HOMO level of PC-DODTBT is -5.11 eV, indicating that the polymer has relatively deep HOMO level. The hole mobility of PC-DODTBT as deduced from SCLC method was found to be 2.03 x 10(-4) cm(2)/Versus Polymer solar cells (PSCs) based on the blends of PC-DODTBT and [6,6]-phenyl-C(71)-butyric acid methyl ester (PC(71)BM) with a weight ratio of 1:2.5 were fabricated. Under AM 1.5 (AM, air mass), 100 mW/cm(-2) illumination, the devices were found to exhibit an open-circuit voltage (V(oc)) of 0.73 V, short-circuit current density (J(sc)) of 5.63 mA/cm(-2), and a power conversion efficiency (PCE) of 1.44%. This photovoltaic performance indicates that the copolymer is promising for polymer solar cells applications. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 123: 99-107, 2012
Quadrature current-reused divide-by-3 semi-dynamic frequency divider with active balun
(2012-01-05)
Lin, C. -Y.
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Rao, P. -Z.
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Lin, Y. -K.
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Chung, S. -J.
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傳播研究所
A divide-by-3 semi-dynamic frequency divider (SDFD) with active balun is presented using the current-reused technique. The proposed SDFD is composed of a Gilbert cell mixer, one stage of static divider and an active balun. The LO switching stage of the Gilbert cell mixer is also the current source of the static frequency divider to construct the current-reused architecture. At the incident power of 0 dBm, this frequency divider operates at the maximum bandwidth of 1100 MHz from 21.5 to 22.6 GHz. The power consumption of the divider is 12 mW at a 1.5 V supply voltage.
CONTROLLER APPARATUS FOR CONTROLLING A MULTIPHASE MULTILEVEL VOLTAGE SOURCE INVERTER AND A METHOD THEREOF
(2012-01-05)
HU Jwu-Sheng
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CHEN Keng-Yuan
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TANG Chi-Him
The present invention provides an apparatus for controlling a multiphase multilevel voltage source inverter. The apparatus includes a signal-generating unit and a converter. The signal-generating unit responds to an input signal to produce a switching strategy control signal and a duration timing control signal corresponding to the switching strategy control signal. The converting unit responds to the switching strategy control signal and the duration timing control signal to produce a switching signal. The voltage source inverter responds to the switching signal to generate a multiphase-and-multilevel AC voltage output.
POWER MONITORING DEVICE FOR IDENTIFYING STATE OF ELECTRIC APPLIANCE AND POWER MONITORING METHOD THEREOF
(2012-01-05)
Tsao Shiao-Li
;
Lai Yi-Sheng
;
Lin Ming-Chun
;
Chen Yung-Chi
A power monitoring device for identifying the state of an electric appliance based on user feedbacks and a power monitoring method thereof are provided. The power monitoring device includes a measurement module, a variation detection and search module, and an electric appliance signature database established based on user feedbacks. When the measurement module detects a variation of a power consumption feature, the variation detection and search module searches the electric appliance signature database according to the variation to obtain electric appliances similar to the variation and the states thereof. A user contributes data to the electric appliance signature database by confirming the search result, or selecting the correct electric appliance and the state thereof. When the user confirms the search result, the power monitoring device establishes an association between the electric appliance and its electric appliance signatures and updates the electric appliance signature database.
交大e-News第109期
(2012-01-05)
Secretariat
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國立交通大學秘書室
METHOD FOR RECORDING, RECOVERING, AND REPLAYING REAL TRAFFIC
(2012-01-05)
LIN YING DAR
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CHENG TSUNG HUAN
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LAI YUAN CHENG
;
CHEN I WEI
A recording, recovering, and replaying method for real traffic is used for processing a plurality of network packets of a plurality of network connections. A recording procedure of the method includes the following steps. A recording parameter (N, M, P) is received. A header and a payload of each network packet of the network connections are completely recorded, and a payload accumulation value of each network connection is accumulated. When one of the payload accumulation values exceeds N, the header of each network packet and first M bytes of the payload are recorded for P consecutive network packets corresponding to the payload accumulation value. When one of the payload accumulation values exceeds N and after the P consecutive network packets of the network connection corresponding to the payload accumulation value are recorded, the header of each network packet is recorded for the network connection corresponding to the payload accumulation value.
Rotational dynamics of solvated carbon dioxide studied by infrared, Raman, and time-resolved infrared spectroscopies and a molecular dynamics simulation
(2012-01-07)
Watanabe, Kaori
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Okajima, Hajime
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Kato, Takuya
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Hamaguchi, Hiro-o
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應用化學系
Rotational dynamics of solvated carbon dioxide (CO(2)) has been studied. The infrared absorption band of the antisymmetric stretch mode in acetonitrile is found to show a non-Lorentzian band shape, suggesting a non-exponential decay of the vibrational and/or rotational correlation functions. A combined method of a molecular dynamics (MD) simulation and a quantum chemical calculation well reproduces the observed band shape. The analysis suggests that the band broadening is almost purely rotational, while the contribution from the vibrational dephasing is negligibly small. The non-exponential rotational correlation decay can be explained by a simple rotor model simulation, which can treat large angle rotations of a relatively small molecule. A polarized Raman study of the symmetric stretch mode in acetonitrile gives a rotational bandwidth consistent with that obtained from the infrared analysis. A sub-picosecond time-resolved infrared absorption anisotropy measurement of the antisymmetric stretch mode in ethanol also gives a decay rate that is consistent with the observed rotational bandwidths. (C) 2012 American Institute of Physics. [doi:10.1063/1.3671998]
捍衛土地　都蘭青年覺醒
(2012-01-08)
鄭巧琪
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Department of Communication and Technology
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傳播與科技學系
都蘭村是位於台東縣東河鄉的原住民部落，為一具有長久歷史的阿美族區域。最近族裡的年輕人強烈意識到土地嚴重流失的問題。因此年輕族人們集合起來，要替族人爭取權益。
傳承感動　僑聯會長陳立忠
(2012-01-08)
楊廣培
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Department of Communication and Technology
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傳播與科技學系
滿足，可以只是看到別人開心的表情。每個人的定義皆不同，所以每個人的故事都不一樣。
灰色的雨　我愛過的1960
(2012-01-08)
蘇冠心
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Department of Communication and Technology
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傳播與科技學系
日本的1960年代，就像是一場永不停歇的雨，灰茫不安的氣氛籠罩了全國，當時年僅27歲的作者川本三郎任職於《朝日雜誌》，因為私下採訪嫌犯並湮滅證據遭到逮捕。事發二十年後，川本三郎將當年發生的事情寫成《我愛過的那個時代》一書，藉由筆下文字，放下心中桎梏已久的六零年代，與存在於那個時空的窒礙感。
機車騎士　三等公民
(2012-01-08)
陳建安
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Department of Communication and Technology
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傳播與科技學系
在台灣狹窄的都市環境裡，許多上班族必須面對擁擠的人潮，對於每天需要通勤的人而言，低油耗、簡便、經濟效益高的機車變成了第一選擇，但是台灣對於機車的路權制定卻非常不健全。這使得台灣一千五百萬以上的機車使用者，成為人數最多、卻也是最弱勢、最被打壓的一個族群。
泳池開幕　票價惹議
(2012-01-08)
楊佳靜
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Department of Communication and Technology
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傳播與科技學系
2011年十二月十二號，新建好的交大室內泳池正式售票營運。新泳池讓許多人躍躍欲試，但游泳池的收費標準，清大和交大學生卻存在不小差距，不少人紛紛表達不滿。