Browsing by Issue Date, starting with "2008-04-16"

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A distributed computation algorithm for solving portfolio problems with integer variables
(2008-04-16)
Li, Han-Lin
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Tsai, Jung-Fa
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資訊管理與財務金融系註：原資管所+財金所
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Department of Information Management and Finance
A portfolio problem with integer variables can facilitate the use of complex models, including models containing discrete asset values, transaction costs, and logical constraints. This study proposes a distributed algorithm for solving a portfolio program to obtain a global optimum. For a portfolio problem with n integer variables, the objective function first is converted into an ellipse function containing n separated quadratic terms. Next, the problem is decomposed into m equal-size separable programming problems solvable by a distributed computation system composed of rn personal computers linked via the Internet. The numerical examples illustrate that the proposed method can obtain the global optimum effectively for large scale portfolio problems involving integral variables. (c) 2007 Elsevier B.V. All rights reserved.
Electrogenerated chemiluminescence of a spirobifluorene-linked bisanthracene: A possible simultaneous, two-electron transfer
(2008-04-16)
Sartin, Matthew M.
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Shu, Chingfong
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Bard, Allen J.
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應用化學系
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資訊工程學系
We report the electrogenerated Chemiluminescence (ECL) of 2,2'-bis(10-phenylanthracen-9-yl)-9,9'-spirobifluorene (spiro-FPA), a dichromophoric molecule composed of two phenylanthracenes linked by a spirobifluorene moiety (PA similar to X similar to PA). The results are compared to those for 9,10-diphenylanthracene (DPA), a related molecule with a single chromophore. Cyclic voltammetry (CV) of spiro-FPA shows two reversible, closely spaced, one-electron transfers on both reduction and oxidation, occurring at E-1,E-red degrees = -2.02, E-2red degrees = -2.07 V vs SCE and E-1,E-OX degrees = 1.14, E-2,E-OX degrees = 1.20 V vs SCE. The potentials for each pair are close enough to appear as a single peak in CV, indicating that the spirobifluorene moiety interrupts conjugation between the redox centers. The potentials observed are similar to those of DPA, which shows E-red degrees = -2.06 V vs SCE and E-OX degrees = 1.15 V vs SCE. The absorbance spectrum of spiro-FPA shows lambda(max,abs) 377 nm, with epsilon(377) = 25 700 M-1 s(-1), while DPA exhibited lambda(max,abs) = 374 nm, with epsilon(374) = 13 800 M-1 s(-1), demonstrating that spiro-FPA has twice the available chromophores as DPA. Photoluminescence (PL) data for spiro-FPA shows lambda(max,PL) = 434 nm, with Phi(PL) = 0.74, while DPA fluoresces at 420 nm with Phi(PL) 0.91; thus, there is greater solvent or structural relaxation in the spiro-FPA excited state, which may account for the greater internal conversion. Unlike DPA, the ECL spectrum of spiro-FPA exhibits long-wavelength emission not observed in the PL. We attribute this emission to excimers formed during annihilation ECL. Steric hindrance prevents DPA from forming excimers, even in ECL, but spiro-FPA annihilation can occur between pairs of di-ions (PA(center dot-)similar to X similar to PA(center dot-) and PA(center dot+)similar to X similar to PA(center dot+)), which are electrostatically more strongly attracted to one another than the mono-ions. This greater electrostatic attraction may be sufficient to overcome the steric hindrance to excimer formation. Lowering the electrolyte concentration decreases the electrostatic shielding of the ions from one another; thus, the increase in longer wavelength ECL accompanying a decrease in electrolyte concentration supports the role of the di-ions in excimer formation. Additionally, simulations show, consistent with experiment, a more rapid decrease in excimer concentration than in excited monomer concentration as a function of time after each potential pulse. This is probably due to the greater number of scavenging reactions available for di-ions. The simulations are confirmed experimentally when lower potential pulsing frequencies yield lower relative excimer emission. Since an excited state created by one-electron transfer between two di-ions should be rapidly quenched via electron transfer by the other PA moiety, the existence of excimers suggests the possibility of simultaneous, two-electron transfer to generate the excimer.
無線網路熱點中動態負載均衡之裝置與方法
(2008-04-16)
曹孝櫟
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徐誌謙
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余泰興
本發明揭露一種無線網路熱點中動態負載均衡之裝置與方法。此裝置包含一資源分配模組和一負載調整單元。此資源分配模組先建立此無線網路熱點中存取點與用戶間的資源模型和關係,並尋找可能的負載均衡轉移路徑,從中選出一負載均衡轉移路徑。根據此路徑,負載調整單元重新分配網路資源並動態調整此無線網路熱點中多個存取點間的負載。本發明適用於集中式與分散式無線通訊系統。
「從科技島到加值島」施振榮專題演講
(2008-04-20)
謝甄芳
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Department of Communication and Technology
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傳播與科技學系
適逢國立交通大學在台建校50週年，4月11日於校內舉辦的校慶相關活動「全球校友商界領袖峰會」中，特地請到『台灣50、影響50』傑出校友名單中的電子產業界菁英─宏碁（Acer）電腦創辦人施振榮先生發表演說，並邀請世界各地菁英校友共襄盛舉，一同分享產業經驗。
拷秋勤唸歌　台灣好嘻哈
(2008-04-20)
賴奕如
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Department of Communication and Technology
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傳播與科技學系
「台灣正宗唸歌團」拷秋勤，秉持以台灣文化及精神為出發點的理念，結合了台灣傳統的音樂素材與新的外來音樂形式，展現出多元的文化可能，不但成功地將外來音樂本土化，讓自己的作品充滿了台灣人的氣息與聲音，更藉由音樂傳達他們的想法與意念。
電子工程學系校慶活動實錄
(2008-04-20)
黃夙蓮
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Department of Communication and Technology
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傳播與科技學系
電工系開幕
薪火相傳曾郁文的台灣原味
(2008-04-20)
鄭瑋津
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Department of Communication and Technology
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傳播與科技學系
藝術家曾郁文為交通大學製作的風動藝術在校慶時舉行剪綵。
《三國之見龍卸甲》
(2008-04-20)
姚翔
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Department of Communication and Technology
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傳播與科技學系
影評
總編輯的話
(2008-04-20)
陳惠玟
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Department of Communication and Technology
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傳播與科技學系
總編輯的話
交大五校校友分享
(2008-04-20)
謝佳慧
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Department of Communication and Technology
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傳播與科技學系
五校校友談交大
書評《燦爛千陽》
(2008-04-20)
李怡萱
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Department of Communication and Technology
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傳播與科技學系
《燦爛千陽》阿富汗悲歌
愛心義賣愛恆二手商店
(2008-04-20)
吳念慈
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Department of Communication and Technology
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傳播與科技學系
為了訓練身心障礙者工作能力，愛恆啟能中心於今年一月份成立「愛恆二手商店」。
校友漫談成功在校學子取經
(2008-04-20)
陳貞儒
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Department of Communication and Technology
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傳播與科技學系
為慶祝交通大學在台建校五十週年，原先預定於西南交大舉辦的「全球校友商業峰會」，今年度特別移師新竹交大舉辦。畢業於兩岸五所交大的傑出校友，紛紛從世界各地前來新竹，參與此次盛會。為了促進交大的在校同學與校友間的交流，校友會特地在峰會首日規劃座談，邀請兩位成功校友前來，讓交大同學與之認識，並挖取兩位前輩的人生經驗。
徐子晨苦練乃致勝關鍵　
(2008-04-20)
汪承漢
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Department of Communication and Technology
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傳播與科技學系
目前就讀國立政治大學外交系大三的徐子晨，其實在大學才開始接觸西洋劍，靠著勤奮的練習，仍憑著短短三年的資歷勇奪九十六年度大專盃個人組及團體組冠軍。
溪州部落　迫遷部落盼聲援
(2008-04-20)
蘇芳儀
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Department of Communication and Technology
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傳播與科技學系
北縣政府因為「大碧潭再造計畫」，必須重整新店溪行水區，被畫如範圍的溪洲部落也面臨拆遷的命運，在許多團體的聲援下，他們自發性舉辦了一些活動，希望透過行動的力量，保留原住地。
馬上現象媒體「周」邊效應
(2008-04-20)
姜建亨
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Department of Communication and Technology
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傳播與科技學系
從馬英九當選後，媒體不斷將焦點放在周美青身上讓人不免摸不著頭緒到底是馬英九當選還是周美青當選？？類似議題層出不窮到底是媒體在大似炒作還是真的有這樣討論的必要？
走在「安全」與「方便」的十字路口中
(2008-04-20)
沈昭邦
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Department of Communication and Technology
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傳播與科技學系
沒有斑馬線卻人人穿越的清夜十字路口
Green Day 龐克搖滾希望
(2008-04-20)
蔡昇峰
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Department of Communication and Technology
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傳播與科技學系
Green day，龐克樂復興最重要的樂團之一，被喻為「九O年代龐克新希望」。繼承了七O年代Sex Pistol等龐克始祖，並突破了流行的限制，用滿滿的能量與精力，以及最簡單易懂的三和弦，將對世俗的不滿完全表現在歌曲上，讓粗糙的龐克搖滾留下了深度，並帶動了後龐克、金屬龐克、ska龐克等的復興。
交大e-News第023期
(2008-04-21)
Secretariat
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國立交通大學秘書室
Ultrafast carrier dynamics of InGaAsN and InGaAs single quantum wells
(2008-04-21)
Hsu, Chih-Chang
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Lin, Ja-Hon
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Chen, Ying-Shu
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Lin, Ying-Hsiu
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Kuo, Hao-Chung
Striking differences in differential reflectance and carrier relaxation in In(0.4)Ga(0.6)As and In(0.4)Ga(0.6)As(0.98)N(0.02) single quantum wells (SQWs) were studied using ultrafast time-resolved photoreflectance. Even with extremely thin SQW of only 60 angstrom within 3000 angstrom wide GaAs confining layers, negative and positive differential reflectance was observed for the excitation photon energy far above the bandgaps at 820 and 880 nm for both samples. Due to absorption by the GaAs confining layer, the peak differential reflectance pumped at 820 nm is an order of magnitude larger than that pumped at 880 nm; and it is larger for InGaAs SQWs than for InGaAsN SQWs. The shorter carrier lifetimes of these samples result from carrier - carrier scattering as pumped at both wavelengths. The longer carrier lifetime as pumped at 880 nm is due to hot phonon decay in InGaAs but may be due to stimulated emission in InGaAsN. The results reveal that the carrier dynamics is strongly affected by N incorporation that causes local defects in InGaAsN SQWs to reduce the carrier relaxation.