Browsing by Issue Date, starting with "2007-12-24"

Now showing 1 - 20 of 58418

Size dependence of the electronic structures and electron-phonon coupling in ZnO quantum dots
(2007-12-24)
Ray, S. C.
;
Low, Y.
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Tsai, H. M.
;
Pao, C. W.
;
Chiou, J. W.
The electronic structures and optical properties of various sizes of ZnO quantum dots (QDs) were studied using x-ray absorption, photoluminescence, and Raman spectroscopy. The increase in the intensity ratio of the second-order Raman spectra of longitudinal optical mode and its fundamental mode, which is related to the strength of the electron-phonon coupling (EPC), is found to increase with the size of QD. The trend of EPC also correlates with the increase of the intensity ratio of the O 2p(pi) (I(pi)) and 2p(sigma) (I(sigma)) orbital features in the O K-edge x-ray absorption near-edge structure (XANES) as the size of QD increases. The EPC and XANES results suggest that the crystal orientations of ZnO QDs are approximately aligned with the c axis parallel with the polarization of x-ray photons. (c) 2007 American Institute of Physics.
Triple-wavelength erbium fiber ring laser based on compound-ring scheme
(2007-12-24)
Yeh, Chien Hung
;
Shih, Fu Yuan
;
Chen, Chang Tai
;
Chi, Sien
;
光電工程學系
A triple-wavelength erbium-doped compound ring fiber laser using the fiber-based triple-ring filter (TRF) is proposed and experimentally investigated. Using the fiber-based TRF laser scheme, the proposed laser can lase three wavelengths simultaneously. The fiber laser retrieve the optical side-mode suppression ratios (SMSRs) of 40.2, 40.4 and 41.6 dB and the output powers of -9, -8.8 and -7.6 dBm at the wavelengths 1555.89, 1556.77 and 1557.66 nm, respectively. The mode spacing of the triple-wavelength fiber laser is nearly 0.9 nm. Moreover, the output power stability of the ring laser has also been measured and analyzed. (c) 2007 Optical Society of America.
Wideband tunable wavelength-selective coupling in asymmetric side-polished fiber coupler with dispersive interlayer
(2007-12-24)
Chen, Nan-Kuang
;
Lee, Cheng-Ling
;
Chi, Sien
;
光電工程學系
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Department of Photonics
We demonstrate tunable highly wavelength-selective filter based on a 2 x 2 asymmetric side-polished fiber coupler with dispersive interlayer in one of the coupling arms. The asymmetric fiber coupler is made of two side-polished fibers using identical single-mode fibers and one of the polished fibers is further chemically etched at the central evanescent coupling region to gain closer to the core. An optical liquid with different dispersion characteristics than that of silica fiber is used to fill up the etched hollow and therefore the propagation constant for the polished fiber with dispersive liquid becomes more dispersive and crosses with that of another untreated polished fiber. The location of the cross point and the cross angle between two propagation constant curves determine the coupling wavelength and coupling bandwidth as well as channel wavelength separation, respectively. The coupling wavelength can be tuned at least wider than 84 nm (1.326-1.410 mu m) under index variation of 0.004 and with coupling ratios of higher than 30 dB. (c) 2007 Optical Society of America.
Cerium oxide nanocrystals for nonvolatile memory applications
(2007-12-24)
Yang, Shao-Ming
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Chien, Chao-Hsin
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Huang, Jiun-Jia
;
Lei, Tan-Fu
;
Tsai, Ming-Jinn
The characteristics of silicon-oxide-nitride-oxide-silicon-type memories embedded with cerium oxide nanocrystals were demonstrated. They were fabricated by depositing a thin CeO(2) film on the SiO(2) tunneling layer and subsequently rapid-thermal annealing process. The mean size and aerial density of the CeO(2) nanocrystals embedded in SiO(2) are estimated to be about 8-10 nm and (3-7)x10(11)/cm(-2) after a high-temperature annealing with different ambients on 900 degrees C. The program/erase behaviors and data retention characteristics were described to demonstrate its advantages for nonvolatile memory device applications. (c) 2007 American Institute of Physics.
A new solution for a partially penetrating constant-rate pumping well with a finite-thickness skin
(2007-12-25)
Chiu, Pin-Yuan
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Yeh, Hund-Der
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Yang, Shaw-Yang
;
環境工程研究所
;
Institute of Environmental Engineering
A mathematical model describing the constant pumping is developed for a partially penetrating well in a heterogeneous aquifer system. The Laplace-domain solution for the model is derived by applying the Laplace transforms with respect to time and the finite Fourier cosine transforms with respect to vertical co-ordinates. This solution is used to produce the curves of dimensionless drawdawn versus dimensionless time to investigate the influences of the patch zone and well partial penetration on the drawdown distributions. The results show that the dimensionless drawdown depends on the hydraulic properties of the patch and formation zones. The effect of a partially penetrating well on the drawdown with a negative patch zone is larger than that with a positive patch zone. For a single-zone aquifer case, neglecting the effect of a well radius will give significant error in estimating dimensionless drawdown, especially when dimensionless distance is small. The dimensionless drawdown curves for cases with and without considering the well radius approach the Hantush equation (Advances in Hydroscience. Academic Press: New York, 1964) at large time and/or large distance away from a test well. Copyright (C) 2007 John Wiley & Sons, Ltd.
第十三期總編輯的話
(2007-12-30)
江柏廷
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Department of Communication and Technology
;
傳播與科技學系
第十三期總編輯的話
沒落的花煙巷弄-歸綏街
(2007-12-30)
謝佳慧
;
Department of Communication and Technology
;
傳播與科技學系
沒落的花煙巷弄-歸綏街
《被出賣的台灣》
(2007-12-30)
沈昭邦
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Department of Communication and Technology
;
傳播與科技學系
上周二（十二月二十五日）適逢聖誕佳節，在眾人享受聖誕晚餐的同時，在交大的另一角落正舉辦著一場演講，主講者正是最近新聞、風波不斷的新聞局局長－謝志偉。在這場主題為《從我留學經驗看台灣》的演講，筆者有幸的從謝志偉手中取得一本他極為推薦的書：《被出賣的台灣》（Formosa Betrayed）。
交大宅男宿舍介紹
(2007-12-30)
汪承漢
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Department of Communication and Technology
;
傳播與科技學系
交大宅男宿舍介紹
《手紙》：罪與罰
(2007-12-30)
林憶宏
;
Department of Communication and Technology
;
傳播與科技學系
電影《手紙》觀後感
「m-flo」混音再現，感動依舊
(2007-12-30)
林暐家
;
Department of Communication and Technology
;
傳播與科技學系
"Loves"熱愛系列最高傑作「COSMICOLOR 宇宙色彩」的完全混音版專輯
星光現象選秀節目一窩蜂
(2007-12-30)
陳惠玟
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Department of Communication and Technology
;
傳播與科技學系
探討現在台灣現有的文化現象
選舉面面觀
(2007-12-30)
陳貞儒
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Department of Communication and Technology
;
傳播與科技學系
立委選舉選期逼近，候選人如何利用各種方式想抓住選民注意呢?
被壓垮的草莓
(2007-12-30)
賴奕如
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Department of Communication and Technology
;
傳播與科技學系
社會不斷出現自殺事件，難道草莓族真的背負了過多的壓力嗎？生命對於他們來說已經不再重要？
我樂故我在阿雞的音樂聯合國
(2007-12-30)
蔡昇峰
;
Department of Communication and Technology
;
傳播與科技學系
一聽到「拷秋勤」這樣的樂團名稱，也許會覺得不知所云，不知道是什麼意思，甚至有的人會聯想到台語的「打手槍」這類粗鄙的用詞。但其實拷秋勤是有相當深刻、典雅意涵的。拷秋勤是指農業作息「春耕、夏耘、秋勤、冬藏」中的「秋勤」，意指農家辛勤收割稻米，「拷」字則代表農夫手持鐮刀收割的動作。
週末好去處
(2007-12-30)
張雅雯
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Department of Communication and Technology
;
傳播與科技學系
照片故事
MCHotdog─放蕩不羈的音樂狂想
(2007-12-30)
陳濡群
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Department of Communication and Technology
;
傳播與科技學系
台灣饒舌一哥聽看看他的音樂對台灣社會帶來甚麼衝擊
《不願面對的真相》不知道還是不願面對？
(2007-12-30)
姜建亨
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Department of Communication and Technology
;
傳播與科技學系
氣候變遷一直都是科學家所關注的問題但是卻一直被大眾所忽視這樣到底是大家不知道的真相還是大家不願面對的真相??
戲劇般的人生－李忠義
(2007-12-30)
姚翔
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Department of Communication and Technology
;
傳播與科技學系
窮小孩白手起家，一生大起大落的個人故事。
Edge-bipancyclicity of conditional faulty hypercubes
(2007-12-31)
Shih, Lun-Min
;
Tan, Jimmy J. M.
;
Hsu, Lih-Hsing
;
資訊工程學系
;
Department of Computer Science
Xu et al. showed that for any set of faulty edges F of an n-dimensional hypercube Q(n) with vertical bar F vertical bar <= n - 1, each edge of Q(n) - F lies on a cycle of every even length from 6 to 2(n), n >= 4, provided not all edges in F are incident with the same vertex. In this paper, we find that under similar condition, the number of faulty edges can be much greater and the same result still holds. More precisely, we show that, for up to vertical bar F vertical bar = 2n - 5 faulty edges, each edge of the faulty hypercube Q(n) - F lies on a cycle of every even length from 6 to 2(n) with each vertex having at least two healthy edges adjacent to it, for n >= 3. Moreover, this result is optimal in the sense that there is a set F of 2n - 4 conditional faulty edges in Q(n) such that Q(n) - F contains no hamiltonian cycle. (c) 2007 Elsevier B.V. All rights reserved.