Browsing by Issue Date, starting with "2011-05-03"

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Ultrafast thermoelastic dynamics of HoMnO3 single crystals derived from femtosecond optical pump-probe spectroscopy
(2011-05-03)
Shih, H. C.
;
Chen, L. Y.
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Luo, C. W.
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Wu, K. H.
;
Lin, J-Y
In this paper, the photo-induced ultrafast thermoelastic dynamics of hexagonal HoMnO3 single crystals has been studied by using optical pump-probe spectroscopy. The thermoelastic effect in the ab-plane of hexagonal HoMnO3, associated with giant magnetoelastic coupling around the Neel temperature (T-N), is intimately correlated to the emergence of a negative component in the transient reflectivity changes (Delta R/R) obtained in temperature-dependent pump-probe experiments. Moreover, the variation in the oscillation period in Delta R/R caused by a strain pulse propagating along the c-axis exhibits an abrupt drop around T-N, presumably due to the antiferromagnetic-ordering-induced changes in ferroelectricity.
Ultrafast thermoelastic dynamics of HoMnO(3) single crystals derived from femtosecond optical pump-probe spectroscopy
(2011-05-03)
Shih, H. C.
;
Chen, L. Y.
;
Luo, C. W.
;
Wu, K. H.
;
Lin, J-Y
In this paper, the photo-induced ultrafast thermoelastic dynamics of hexagonal HoMnO(3) single crystals has been studied by using optical pump-probe spectroscopy. The thermoelastic effect in the ab-plane of hexagonal HoMnO3, associated with giant magnetoelastic coupling around the Neel temperature (T(N)), is intimately correlated to the emergence of a negative component in the transient reflectivity changes (Delta R/R) obtained in temperature-dependent pump-probe experiments. Moreover, the variation in the oscillation period in Delta R/R caused by a strain pulse propagating along the c-axis exhibits an abrupt drop around T(N), presumably due to the antiferromagnetic-ordering-induced changes in ferroelectricity.
Tube bundle heat exchanger of constant temperature gradient for thermophoretic deposition of aerosol particles
(2011-05-03)
Tsai Chuen-Jinn
;
Huang Shih-Hsuan
;
Chien Chih-Liang
This invention is a tube bundle heat exchanger for thermophoretic deposition of aerosol particles. It has a housing with an internal chamber, and several cold and hot tubes. The cold and hot tubes are arranged in a staggered manner in the internal chamber of the housing. Low and high temperature fluids flow inside the cold and hot tubes, respectively. When the exhaust gas passes through the chamber, temperature gradient between the cold and hot tubes causes aerosol particles suspended in the exhaust gas to deposit on the surface of cold tubes to achieve the treatment of exhaust gas. Staggered arrangement of cold and hot tubes can maintain nearly constant temperature gradient in the direction of the gas flow thereby enhances the overall removal efficiency of particles.
Dynamics of stock market integration between the US and the BRIC
(2011-05-04)
Sheu, Her-Jiun
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Liao, Chun-Huang
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管理科學系
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Department of Management Science
This study investigates the evolving pattern of integration and Granger-causality relationships between the developed US and developing BRIC stock markets. The study uses both the linear Engle-Granger cointegration test and the nonlinear Enders-Siklos cointegration test for comparative analysis, and it expands the consistent momentum threshold autoregressive model and the threshold error correction model by time-varying approaches for dynamic analysis. The evidence demonstrates that both long-run time-varying nonlinear cointegration relationships and short-run time-varying Granger-causality relationships exist between the stock markets of US-Brazil, US-India, US-Russia and US-China (US-BRIC). Furthermore, these relationships were altered in the short-run during 2007/2008, when the subprime mortgage financial crisis in the US occurred. The empirical results demonstrate that the stock markets of Brazil, Russia and China have begun exerting significant influences on the Dow Jones to some extent after 2006, and the Dow Jones index continues to play a dominant role and increasingly, Granger-causing shifts in the emerging markets of Russia, India and China. The findings demonstrate the time-varying nature of the nonlinear cointegration and Granger-causality relationships, and also indicate that the potential benefits from international risk diversification may have gradually diminished between these studied markets.
Ferromagnetic Enhancement of CE-Type Spin Ordering in (Pr, Ca)MnO(3)
(2011-05-04)
Zhou, S. Y.
;
Zhu, Y.
;
Langner, M. C.
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Chuang, Y. -D.
;
Yu, P.
We present resonant soft x-ray scattering results from small bandwidth manganites (Pr, Ca)MnO(3), which show that the CE-type spin ordering (SO) at the phase boundary is stabilized only below the canted antiferromagnetic transition temperature and enhanced by ferromagnetism in the macroscopically insulating state (FM-I). Our results reveal the fragility of the CE-type ordering that underpins the colossal magnetoresistance effect in this system, as well as an unexpected cooperative interplay between FM-I and CE-type SO which is in contrast to the competitive interplay between the ferromagnetic metallic state and CE-type ordering.
Adaptive second-order control of transmitter power in wireless communication systems
(2011-05-04)
Wu, C. -H.
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Lin, C. -A.
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電控工程研究所
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Institute of Electrical and Control Engineering
The authors consider transmitter power control of wireless communication systems. They propose an adaptive second-order distributed power control algorithm in which the relaxation factors are adaptively adjusted to improve the rate of convergence. The algorithm updates power using a weighted combination of the distributed power control algorithm and the second-order power control (SOPC) algorithm. Simulation results show performance improvement over distributed constrained power control and constrained SOPC.
從唐宋詩詞看中國人的審美觀
(2011-05-04)
呂正惠
;
開放教育推動中心
;
Open Education Office
課程首頁本課程是由交通大學新文藝復興閱讀計畫提供。 96 年 8 月當各大學紛紛摩拳擦掌準備迎接新生的同時，交通大學校長吳重雨則因為一則來自於七月份泰晤士報，有關於英國首相布朗公布其夏日讀書清單的新聞中，看到了他對知識的尊重。在這同時，吳重雨校長也思考著，要如何為學生準備追求知識的環境和激發他們對知識的尊重與喜愛。台積電張忠謀董事長曾陳述他 18 歲進入哈佛那一年，博覽文史哲理工經典群籍，至此奠定了他求知的基礎，並借海明威名言，將其改為「哈佛這一年為人生可帶走的盛宴。」吳重雨校長以張董事長的學習為借鏡，認為學生固然能藉由自我閱讀的方式學習到豐沛的知識，但透過名人、大師親臨現場地介紹經典書籍，更能加深學子們對於書籍的認識與興趣，這也是「新文藝復興閱讀計劃」 ( 以下簡稱 : 「經典名著選讀」 ) 活動展開籌劃的緣由。於是，吳重雨校長便積極敦請「交大通識教育委員會」，接手籌備本計劃的相關活動，而該中心也成為實際施行本計畫的策動、開課以及認證單位。至此，期許交大學子藉由閱讀、聽講來提昇人文素養、開拓視野的「新文藝復興閱讀計劃」，就此展開。
Plasma-made silicon nanograss and related nanostructures
(2011-05-04)
Shieh, Jiann
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Ravipati, Srikanth
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Ko, Fu-Hsiang
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Ostrikov, Kostya (Ken)
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材料科學與工程學系
Plasma-made nanostructures show outstanding potential for applications in nanotechnology. This paper provides a concise overview on the progress of plasma-based synthesis and applications of silicon nanograss and related nanostructures. The materials described here include black silicon, Si nanotips produced using a self-masking technique as well as self-organized silicon nanocones and nanograss. The distinctive features of the Si nanograss, two-tier hierarchical and tilted nanograss structures are discussed. Specific applications based on the unique features of the silicon nanograss are also presented.
Ferromagnetic Enhancement of CE-Type Spin Ordering in (Pr, Ca)MnO3
(2011-05-04)
Zhou, S. Y.
;
Zhu, Y.
;
Langner, M. C.
;
Chuang, Y. -D.
;
Yu, P.
We present resonant soft x-ray scattering results from small bandwidth manganites (Pr, Ca)MnO3, which show that the CE-type spin ordering (SO) at the phase boundary is stabilized only below the canted antiferromagnetic transition temperature and enhanced by ferromagnetism in the macroscopically insulating state (FM-I). Our results reveal the fragility of the CE-type ordering that underpins the colossal magnetoresistance effect in this system, as well as an unexpected cooperative interplay between FM-I and CE-type SO which is in contrast to the competitive interplay between the ferromagnetic metallic state and CE-type ordering.
LIGHTING CONTROL MODULE, VIDEO CAMERA COMPRISING THE SAME AND CONTROL METHOD OF THE SAME
(2011-05-05)
Chuang Jen-Hui
;
Lo Kuo-Hua
;
Hung Pang-Chan
The present invention provides a lighting control module, a video camera comprising the same and a control method of the same. The video camera of the invention includes a sensing module, a light-emitting module and a control module. The sensing module receives a reflected light beam from a recording direction of the video camera, and generates an image of a scene in the recording direction. The light-emitting module emits a light toward the recording direction. Additionally, the lighting control module is connected to the light-emitting module for controlling the light-emitting module to periodically emit the light from a first brightness to a second brightness.
Infrared Electroabsorption Spectroscopy of N,N-Dimethyl-p-nitroaniline in Acetonitrile/C(2)Cl(4): Solvation of the Solute and Self-Association of Acetonitrile
(2011-05-05)
Wang, Wei-Chieh
;
Shigeto, Shinsuke
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應用化學系
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應用化學系分子科學碩博班
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Department of Applied Chemistry
Solvated structures of N,N-dimethyl-p-nitroaniline (DMPNA), an analog of p-nitroaniline (PNA), and self-associated structures of acetonitrile (ACN) in mixed solvents of ACN and C(2)Cl(4) were studied using infrared (IR) electroabsorption and FTIR spectroscopies. IR electroabsorption spectroscopy measures changes in IR absorption intensity upon application of external electric field modulation, which are a sensitive probe for permanent dipole moments. In ACN/CCl(4), PNA has been shown to occur as two distinct solvated forms, namely, 1:1 and 1:2 forms, which have one and two ACN molecule(s), respectively, associated with PNA. The IR electroabsorption and FTIR measurements on DMPNA show that, unlike PNA, DMPNA occurs as a monomer in ACN/C(2)Cl(4) rather than as specific solvated structures analogous to the 1:1 and 1:2 forms because of the substitution effect. Not only does the N, N-dimethyl substitution in DMPNA hamper solvation of ACN at the N(CH(3))(2) group, but it also indirectly blocks strong interactions with ACN at the NO(2) group. Furthermore, by using the AA signal of DMPNA as an internal intensity standard, it was found that the dipole moment of ACN in the DMPNA/ACN/C(2)Cl(4) system is about 1.5 times larger than that of the ACN monomer in dilute CCl(4) solution. This large value of the dipole moment in the solution studied here is attributable to the formation of a head-to-tail linear dimer of ACN, whereas the antiparallel dimer is energetically more favorable in the gas phase.
Infrared Electroabsorption Spectroscopy of N,N-Dimethyl-p-nitroaniline in Acetonitrile/C2Cl4: Solvation of the Solute and Self-Association of Acetonitrile
(2011-05-05)
Wang, Wei-Chieh
;
Shigeto, Shinsuke
;
應用化學系
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應用化學系分子科學碩博班
;
Department of Applied Chemistry
Solvated structures of N,N-dimethyl-p-nitroaniline (DMPNA), an analog of p-nitroaniline (PNA), and self-associated structures of acetonitrile (ACN) in mixed solvents of ACN and C2Cl4 were studied using infrared (IR) electroabsorption and FTIR spectroscopies. IR electroabsorption spectroscopy measures changes in IR absorption intensity upon application of external electric field modulation, which are a sensitive probe for permanent dipole moments. In ACN/CCl4, PNA has been shown to occur as two distinct solvated forms, namely, 1:1 and 1:2 forms, which have one and two ACN molecule(s), respectively, associated with PNA. The IR electroabsorption and FTIR measurements on DMPNA show that, unlike PNA, DMPNA occurs as a monomer in ACN/C2Cl4 rather than as specific solvated structures analogous to the 1:1 and 1:2 forms because of the substitution effect. Not only does the N, N-dimethyl substitution in DMPNA hamper solvation of ACN at the N(CH3)(2) group, but it also indirectly blocks strong interactions with ACN at the NO2 group. Furthermore, by using the AA signal of DMPNA as an internal intensity standard, it was found that the dipole moment of ACN in the DMPNA/ACN/C2Cl4 system is about 1.5 times larger than that of the ACN monomer in dilute CCl4 solution. This large value of the dipole moment in the solution studied here is attributable to the formation of a head-to-tail linear dimer of ACN, whereas the antiparallel dimer is energetically more favorable in the gas phase.
交大e-News第093期
(2011-05-05)
Secretariat
;
國立交通大學秘書室
The influence of carbon addition on carbide characteristics and mechanical properties of CM-681LC superalloy using fine-grain process
(2011-05-05)
Wei, Chao-Nan
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Bor, Hui-Yun
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Chang, Li
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材料科學與工程學系
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Department of Materials Science and Engineering
This study investigates how carbon addition affects the carbide characteristics and mechanical properties of CM-681LC nickel-base superalloy with grain size of 80 mu m prepared using the fine-grain process. Experimental results indicate that carbon addition from 0.11 wt% to 0.15 wt% greatly increases the amount of carbides, but the shape and size of carbides are similar due to the short solidification time of the fine-grain process, which limits the growth of carbides. The increase of carbides by proper carbon addition effectively improves the tensile strength by about 5% and the tensile elongation by over 30% at room and moderate temperatures (21-760 degrees C). The fracture analyses reveal that the carbon addition in fine-grain CM-681LC superalloy can changes the fracture modes from typical intergranular fracture modes to transgranular and intergranular mixed modes. The better carbon content of CM-681LC superalloy applied in the fine-grain process is 0.15 wt%, which has better mechanical properties. (C) 2011 Elsevier B.V. All rights reserved.
Three-Component and Nonclassical Reaction of Phosphines with Enynes and Aldehydes: Formation of gamma-Lactones Featuring alpha-Phosphorus Ylides
(2011-05-06)
Deng, Jie-Cheng
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Chuang, Shih-Ching
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應用化學系
;
Department of Applied Chemistry
Inverted carbenoid species, generated from attack of phosphines at the alpha(delta')-carbon of hex-2-en-4-ynedioic acid dialkyl esters, react with aldehydes to give gamma-lactones possessing an alpha-phosphorus ylide moiety.
Arabidopsis Argonaute 2 Regulates Innate Immunity via miRNA393*-Mediated Silencing of a Golgi-Localized SNARE Gene, MEMB12
(2011-05-06)
Zhang, Xiaoming
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Zhao, Hongwei
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Gao, Shang
;
Wang, Wei-Chi
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Katiyar-Agarwal, Surekha
Argonaute (AGO) proteins are critical components of RNA silencing pathways that bind small RNAs and mediate gene silencing at their target sites. We found that Arabidopsis AGO2 is highly induced by the bacterial pathogen Pseudomonas syringae pv. tomato (Pst). Further genetic analysis demonstrated that AGO2 functions in antibacterial immunity. One abundant species of AGO2-bound small RNA is miR393b*, which targets a Golgi-localized SNARE gene, MEMB12. Pst infection downregulates MEMB12 in a miR393b*-dependent manner. Loss of function of MEMB12, but not SYP61, another intracellular SNARE, leads to increased exocytosis of an antimicrobial pathogenesis-related protein, PR1. Overexpression of miR393b* resembles memb12 mutant in resistance responses. Thus, AGO2 functions in antibacterial immunity by binding miR393b* to modulate exocytosis of antimicrobial PR proteins via MEMB12. Since miR393 also contributes to antibacterial responses, miR393*/miR393 represent an example of a miRNA*/miRNA pair that functions in immunity through two distinct AGOs: miR393* through AGO2 and miR393 through AGO1.
堅持正義　女工改變歷史
(2011-05-08)
張芳瑜
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Department of Communication and Technology
;
傳播與科技學系
1968年英國倫敦福特汽車工廠的罷工事件，引發全球性的影響。在汽車工廠縫製車椅的工廠女工，決定不再默默忍受一直以來性別造成的不公平待遇，勇敢站出來爭取自己的權利。她們所引發的一連串效應至今影響深遠…
何欣茹　在輪椅上舞動生命
(2011-05-08)
尹亭雅
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Department of Communication and Technology
;
傳播與科技學系
一個身為田徑選手的九歲小女孩，因為一場火車意外，粉碎了她的雙腿，也粉碎了她的夢想，但是身體的殘缺和內心的遺憾並沒有阻擋她挑戰生命的勇氣，她用輪椅替代雙腳，用舞蹈填補空缺，將人生活得加倍精彩。她是何欣茹，2004年世界輪標舞大賽第四名，亞洲第一名、第四屆全球熱愛生命獎章得主。
不老騎士　感動從何而來
(2011-05-08)
陳俐吟
;
Department of Communication and Technology
;
傳播與科技學系
追尋在旅行電影裡一直有著崇高的地位，而紀錄片《不老騎士》正是用對夢想的執著感動所有人，但，人們為什麼會被它感動呢？
工作犬懂了沒
(2011-05-08)
黃萱如
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Department of Communication and Technology
;
傳播與科技學系
狗兒在你心中的定義是甚麼呢?如果你腦中只浮現「可愛的寵物的代名詞」的話，趕緊來了解狗兒們的其他身分吧！