Browsing by Issue Date, starting with "2009-11-01"

Now showing 1 - 20 of 49544

Effects of a Modulated Electric Field on the Optical Absorption Spectra in a Single-Layer Graphene
(2009-11-01)
Chiu, Yu-Huang
;
Ho, Jon-Hsu
;
Ho, Yen-Hung
;
Chuu, Der-San
;
Lin, Ming-Fa
The optical absorption spectra of a graphene monolayer in the presence of a modulated electric field are investigated by the gradient approximation with tight-binding model. Such a field could strongly affect the low-energy electronic and optical properties. The low-energy bands exhibit two kinds of band-edge states (mu and nu), which lead to many prominent asymmetric peaks in the density of states (DOS). The finite DOS at omega = 0 implies that a single layer graphene in the presence of modulated electric fields would become a semimetallic one. The low-frequency optical absorption spectra display rich peaks and they vanish at omega = 0. Such absorption peaks mainly result from the two kinds of band-edge states and could be divided into two groups. However, they could not be ascribed to an obvious selection rule. It is worth noting that the optical absorption spectra could show anisotropic features in different modulated directions. The predicted results could be verified by the experimental measurements.
Process and properties of the carbon nanotube assisted LiCoO(2) thin-film battery electrode by pulsed laser deposition
(2009-11-01)
Lo, An-Ya
;
Sun, Chuan-Shu
;
Tseng, Wen-Shou
;
Kuo, Cheng-Tzu
;
材料科學與工程學系
In this study, a pulsed laser deposition process was developed to deposit a carbon nanotube (CNT) assisted LiCoO(2) electrode to improve its power density. The electrodes were deposited on Pt-coated Si substrates with Ar and O(2) as sputtering gases and LiCoO(2)+C as the target. The results indicate that the working pressure is the most important parameter to control the composition of the electrode. Therefore, electrodes with a three-layer structure (i.e., LiCoO(2)-rich/CNT-rich/LiCoO(2)-rich) were fabricated by a three-step deposition process by varying the pressures from 13 to 1.3x10(4) Pa and then 13 Pa again, and it was found that the charge/discharge capacity became approximately 1.5 times greater than that in the corresponding electrode without a CNT-rich layer. The results also indicate that a higher substrate temperature is favorable for improving the crystallinity of the electrode to approach LiCoO(2) crystals.
Fault-Tolerant Hamiltonian Connectivity and Fault-Tolerant Hamiltonicity of the Fully Connected Cubic Networks
(2009-11-01)
Ho, Tung-Yang
;
Lin, Cheng-Kuan
;
資訊工程學系
;
Department of Computer Science
Many papers on the fully connected cubic networks have been published for the past several years due to its favorite properties. In this paper, we consider the fault-tolerant hamiltonian connectivity and fault-tolerant hamiltonicity of the fully connected cubic network. We use FCCN(n) to denote the fully connected cubic network of level n. Let G = (V, E) be a graph. The fault-tolerant hamiltonian connectivity H(f)(k) (G) is defined to be the maximum integer l such that G - F remains hamiltonian connected for every F subset of V(G) boolean OR E(G) with vertical bar F vertical bar <= l. The fault-tolerant hamiltonicitly H(f)(G) is defined to be the maximum integer l such that G - F remains hamiltonian for every F subset of V(G) boolean OR E(G) with vertical bar F vertical bar <= l. We prove that H(f)(k) (FCCN(n)) = 0 and H(f)(FCCN(n)) = 1 if n >= 2.
Predicting protein subnuclear localization using GO-amino-acid composition features
(2009-11-01)
Huang, Wen-Lin
;
Tung, Chun-Wei
;
Huang, Hui-Ling
;
Ho, Shinn-Ying
;
生物科技學系
The nucleus guides life processes of cells. Many of the nuclear proteins participating in the life processes tend to concentrate on subnuclear compartments. The subnuclear localization of nuclear proteins is hence important for deeply understanding the construction and functions of the nucleus. Recently, Gene Ontology (GO) annotation has been used for prediction of subnuclear localization. However, the effective use of GO terms in solving sequence-based prediction problems remains challenging, especially when query protein sequences have no accession number or annotated GO term. This study obtains homologies of query proteins with known accession numbers using BLAST to retrieve GO terms for sequence-based subnuclear localization prediction. A prediction method PGAC, which involves mining informative GO terms associated with amino acid composition features, is proposed to design a support vector machine-based classifier. PGAC yields 55 informative GO terms with training and test accuracies of 85.7% and 76.3%, respectively, using a data set SNL-35 (561 proteins in 9 localizations) with 35% sequence identity. Upon comparison with Nuc-PLoc, which combines amphiphilic pseudo amino acid composition of a protein with its position-specific scoring matrix, PGAC using the data set SNL_80 yields a leave-one-out cross-validation accuracy of 81.1%, which is better than that of Nuc-PLoc, 67.4%. Experimental results show that the set of informative GO terms are effective features for protein subnuclear localization. The prediction server based on PGAC has been implemented at http://iclab.life.nctu.edu.tw/prolocgac. (C) 2009 Elsevier Ireland Ltd. All rights reserved.
低密度合金材料及其製法
(2009-11-01)
劉增豐
;
李堅瑋
一種低密度之合金材料及其製法，其主要組成以重量百分比計，此合金材料含有重量百分比大於等於15小於等於22.5的錳，大於等於7.2小於等於9.0的鋁，大於等於5.1小於等於7.8的鉻，大於等於0.6小於等於1.2的碳及其餘比例為鐵所組合而成。上述揭示之合金成分之合金材料製作高爾夫球桿頭時，不需任何鍛造及軋延等熱作和冷作塑性加工，即可使高爾夫球桿頭具有極佳的延伸性、強度、吸震性及抗蝕性等特性，大幅降低目前的生產成本。
Protein purification involving a unique auto-cleavage feature of a repeated EAAAK peptide
(2009-11-01)
Wu, Yue-Jin
;
Fan, Chia-Ying
;
Li, Yaw-Kuen
;
交大名義發表
;
National Chiao Tung University
A network-based approach for increasing discrimination in data envelopment analysis
(2009-11-01)
Liu, J. S.
;
Lu, W-M
;
Yang, C.
;
Chuang, M.
;
交大名義發表
Data envelopment analysis (DEA) is known to produce more than one efficient decision-making unit (DMU). This paper proposes a network-based approach for further increasing discrimination among these efficient DMUs. The approach treats the system under study as a directed and weighted network in which nodes represent DMUs and the direction and strength of the links represent the relative relationship among DMUs. In constructing the network, the observed node is set to point to its referent DMUs as suggested by DEA. The corresponding lambda values for these referent DMUs are taken as the strength of the network link. The network is weaved by not only the full input/output model, but also by models of all possible input/output combinations. Incorporating these models into the system basically introduces the merits of each DMU under various situations into the system and thus provides the key information for further discrimination. Once the network is constructed, the centrality concept commonly used in social network analysis-specifically, eigenvector centrality-is employed to rank the efficient DMUs. The network-based approach tends to rank high the DMUs that are not specialized and have balanced strengths.
撫慰人心的溫暖
(2009-11-01)
吳雨璇
;
Department of Communication and Technology
;
傳播與科技學系
大二那年的暑假跟表姊在阿里山第一次看到的日出，到現在還歷歷在目，還清楚記得當時那個撼動我心的日出。明明是暑假，太陽出來前的阿里山上卻冷的像十二月的寒冬，坐上小火車一路從沼平搖到祝山，在沒有路燈的山路上往前跑，直到擠上山頭，擠到人群的最前面，和擁擠的人潮一起等待難得的朝陽。時間一分一秒的過去，興奮期待的心情在太陽升起的一瞬間爆發，我們心裡再也容不下別的事情，有的只是暖暖的感動，當下彷彿再也沒有什麼事難得倒我，得到太陽無窮無盡的力量。
Confinement-enhanced dots-in-a-well QDIPs with operating temperature over 200 K
(2009-11-01)
Ling, H. S.
;
Wang, S. Y.
;
Lee, C. P.
;
Lo, M. C.
;
電子工程學系及電子研究所
LWIR InAs/Al(0.3)Ga(0.7)As/In(0.15)Ga(0.85)As confinement-enhanced DWELL (CE-DWELL) QDIPs with operation temperatures higher than 200 K are reported. A thin Al(0.3)Ga(0.7)As barrier layer was inserted above the InAs QDs to improve the confinement of QD states in the In(0.15)Ga(0.85)As DWELL structure and the device performance. The better confinement of the electronic states increases the oscillator strength of the infrared absorption. The higher excited state energy also improves the escape probability of the photoelectrons. Compared with the conventional DWELL QDIPs, the quantum efficiency increases for more than 20 times and the detectivity is an order of magnitude higher at 77 K. With better device parameters of CE-DWELL, it is possible to achieve high quantum efficiency, high operating temperature and long wavelength detection at the same time. (C) 2009 Elsevier B.V. All rights reserved.
面具前與後狂歡嘉年華
(2009-11-01)
林穎瑄
;
Department of Communication and Technology
;
傳播與科技學系
三公尺高的人偶、彩色旗幟的服裝、普天歡騰的鼓聲，和你覺對不會想錯過的 ─義大利嘉年華。
First Principles Calculations of Linear and Second-Order Optical Responses in Rhombohedrally Distorted Perovskite Ternary Halides, CsGeX3 (X = Cl, Br, and I)
(2009-11-01)
Tang, Li-Chuan
;
Chang, Yia-Chung
;
Huang, Jung-Yau
;
Lee, Ming-Hsien
;
Chang, Chen-Shiung
Systematic studies based on first-principles calculations of second. order optical susceptibilities as well as the dielectric function of CsGeX3 (X = Cl Br, and I, CGX) are presented The relationship between structural properties and optoelectronic responses are examined The structural factors Delta alpha, and d(Ge), d(x) are proposed to describe the degree of distortion from an ideal perovskite structure. Delta alpha and dGe increase when halide anions are changed from Cl to I, while halide anion displacement, dx, decreases. The structural distortion effect on these rhombohedral CGX crystals is analyzed by first-principles calculations The dielectric function and the second harmonic generation (SHG) response coefficient also increase with increasing Delta alpha and d(Ge). The direct band gaps (E-c) of CsGeX3 ail occur at the R-point, Delta E-R The experimental band gaps of CGX crystals become smaller. i e, E-G(CGI) (= 3 67eV) > E-G(CGB) (=2 32 eV) > E-G(CGI) (= 1 53eV), as Delta alpha and el increase, i e. d(Ge)(CGC) < d(Ge)(CGR) < d(GB)(CGI) Partial density of states (PDOS) analysis revealed that the valence band maximum (VBM) and conduction band minimum (CBM) are mainly contributed by the p-orbitals of germanium. The calculated magnitudes of chi((2))(ijk) are close to some reported experimental values near the band gap (C) 2009 The Japan Society of Applied Physics
劃不下的句點
(2009-11-01)
蔡欣穎
;
Department of Communication and Technology
;
傳播與科技學系
我與他的故事，不知道何時有結局，我希望快點知道結果，但是，我知道的，會捨不得。
Using fuzzy TOPSIS method for evaluating the competitive advantages of shopping websites
(2009-11-01)
Sun, Chia-Chi
;
Lin, Grace T. R.
;
科技管理研究所
;
Institute of Management of Technology
Taking into consideration technology acceptance factors, website service quality and specific holdup cost factors, this research explores how shopping websites to establish their competitive advantages through these dimensions. We begin with an examination of the literature on shopping websites about its competitive advantages upon which we propose a conceptual framework. Then this research adopts the fuzzy TOPSIS as the analytical tool that determines the weights of each criterion. Fuzzy theory provides a proper tool to encounter with uncertainties and complex environment. The purpose of this paper is to use the fuzzy TOPSIS method based on fuzzy sets in solving MCDM problems. From our research results, the security and trust are the most important factors for improving the competitive advantage of shopping website. Moreover, the PCHome and Yahoo Taiwan rank the first two positions for shopping websites. This paper draws on the research results for implications of managerial practice, and then suggests some empirical tactics in order to enhance management performance for the website shopping industry. (C) 2009 Elsevier Ltd. All rights reserved.
The transition mechanisms of quantum-dot/quantum-well mixed-mode infrared photodetectors
(2009-11-01)
Lin, Shih-Yen
;
Chou, Shu-Ting
;
Lin, Wei-Hsun
;
光電工程學系
;
Department of Photonics
The transition mechanisms of a 10-period quantum-dot (QD)/quantum-well (QW) mixed-mode infrared photodetector is investigated in this paper. Both mid-wavelength infrared (MWIR) and long-wavelength infrared (LWIR) responses are observed for the device. The lower normal incident absorption of the LWIR peak suggests that the QW intra-band transition is responsible for the response while the QD intra-band transition for the MWIR response. Due to the coexistence of MWIR and LWIR responses, the MWIR response should be resulted from one-photon transition while the LWIR response from the two-photon transition. To explain the transition mechanisms of the MMIP device, a model is proposed in this paper. The increases of both MWIR and LWIR responses with increasing measurement temperatures observed for the device are attributed to the increase of electrons in the QW ground state/wetting layer state resulted from the increase of one-photon absorption process with increasing temperatures. (C) 2009 Elsevier B.V. All rights reserved.
A minimal energy tracking method for non-radially symmetric solutions of coupled nonlinear Schrodinger equations
(2009-11-01)
Kuo, Yueh-Cheng
;
Lin, Wen-Wei
;
Shieh, Shih-Feng
;
Wang, Weichung
;
應用數學系
We aim at developing methods to track minimal energy solutions of time-independent m-component coupled discrete nonlinear Schrodinger (DNLS) equations. We first propose a method to find energy minimizers of the 1-component DNLS equation and use it as the initial point of the m-component DNLS equations in a continuation scheme. We then show that the change of local optimality occurs only at the bifurcation points. The fact leads to a minimal energy tracking method that guides the choice of bifurcation branch corresponding to the minimal energy solution curve. By combining all these techniques with a parameter-switching scheme, we successfully compute a non-radially symmetric energy minimizer that can not be computed by existing numerical schemes straightforwardly. (C) 2009 Elsevier Inc. All rights reserved.
OSNP: Secure wireless authentication protocol using one-time key
(2009-11-01)
Huang, Y. L.
;
Lu, P. H.
;
Tygar, J. D.
;
Joseph, A. D.
;
電控工程研究所
Handover security and efficiency have become more and more important in modern wireless network designs. In this paper, we propose a new protocol using the one-time key for user authentication. The proposed protocol can support both intra-domain and inter-domain authentications efficiently. Our protocol requires five messages for intra-domain initial authentication; three for subsequent authentication; and five for handover authentication. No authentication server is needed during handover, and our design reduces the computing load on the authentication server. We show an integration and implementation of EAP from 802.1X and our protocol, giving an easy way to apply our protocol on existing 802.11 wireless networks. The proposed protocol is realized and verified on the SWOON secure wireless testbed. (C) 2009 Elsevier Ltd. All rights reserved.
政治冷感成為青年風氣
(2009-11-01)
徐瑩峰
;
Department of Communication and Technology
;
傳播與科技學系
近來美國牛肉、兩岸經濟合作架構協議（ECFA）等議題，在各大媒體上引起沸沸揚揚的討論，但卻不見該話題在新一代年輕族群中，有任何生存的空間。野草莓學運、美國牛肉進口與ECFA這些議題都不是年輕族群政治冷感的特例。
鴨子與鴨子們的快樂生活
(2009-11-01)
黃艾如
;
Department of Communication and Technology
;
傳播與科技學系
一直到有一天，我發現我許久不見的朋友，用狐疑的眼光盯著我說：「這裡怎麼會有隻鴨子？好吵。」我才發現，原來我變成一隻鴨子了。
Toward the Human-Robot Co-Existence Society: On Safety Intelligence for Next Generation Robots
(2009-11-01)
Weng, Yueh-Hsuan
;
Chen, Chien-Hsun
;
Sun, Chuen-Tsai
;
交大工研院聯合研發中心
;
NCTU/ITRI Joint Research Center
Technocrats from many developed countries, especially Japan and South Korea, are preparing for the human-robot co-existence society that they believe will emerge by 2030. Regulators are assuming that within the next two decades, robots will be capable of adapting to complex, unstructured environments and interacting with humans to assist with the performance of daily life tasks. Unlike heavily regulated industrial robots that toil in isolated settings, Next Generation Robots will have relative autonomy, which raises a number of safety issues that are the focus of this article. Our purpose is to describe a framework for a legal system focused on Next Generation Robots safety issues, including a Safety Intelligence concept that addresses robot Open-Texture Risk. We express doubt that a model based on Isaac Asimov's Three Laws of Robotics can ever be a suitable foundation for creating an artificial moral agency ensuring robot safety. Finally, we make predictions about the most significant Next Generation Robots safety issues that will arise as the human-robot co-existence society emerges.
Characterization of AC Hot-Carrier Effects in Poly-Si Thin-Film Transistors
(2009-11-01)
Lin, Horng-Chih
;
Chang, Kai-Hsiang
;
Huang, Tiao-Yuan
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
In this paper, we employed a new test structure to characterize the alternating-current (ac) hot-carrier (HC)induced degradation in poly-Si thin-film transistors. High sensitivity in detecting the damage and the capability of directly resolving the damage location are demonstrated due to the unique feature of the test structure. Our results indicate that the major degradation is induced in the turn-off stages of the ac-stress signal when applied to the gate and in the turn-on stages of the ac-stress signal when applied to the drain. The availability and energy relaxation of channel HCs are considered to explain the experimental findings.