Browsing by Issue Date, starting with "2008-07-01"

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楓葉造反
(2008-07-01)
管管
AHP- and simulation-based budget determination procedure for public building construction projects
(2008-07-01)
Lai, Yu-Ting
;
Wang, Wei-Chih
;
Wang, Han-Hsiang
;
土木工程學系
;
Department of Civil Engineering
Public construction project budgets account for a high percentage of annual government budgets. Thus, objectively determining project budgets is of priority concern for effectively allocating these budgets by government officers. However, Taiwanese regulations for setting construction project budgets only qualitatively describe the governmental administration process. Without a systematic quantitative method, government officers typically determine project budgets based on their personal experience; thus, budgeting results can be unreliable. This study presents a novel procedure for determining construction project budgets. The proposed procedure integrates an analytical hierarchy process (AHP)-based multi-criteria evaluation model with a simulation-based cost model. The AHP reflects officer evaluations with respect to budget determination criteria. Cost items are variables. The cost model generates a cumulative cost distribution for establishing project budget boundaries. The merits of the proposed procedure are demonstrated through its application to a Taiwanese project. (C) 2007 Elsevier B.V. All rights reserved.
記憶裝置及其資料提供方法
(2008-07-01)
楊惠親
;
鍾崇斌
;
單智君
本發明係揭露一種記憶裝置及其資料提供方法,此記憶裝置接收一處理器所發送之初始指令位址之後,便可動態預測及產生下一個指令之位址,並以所產生之位址至記憶單元陣列提取指令,將此指令傳送予處理器。藉此,記憶裝置可自主性地向處理器傳送指令,不需等待處理器提供指令位址,因此本發明之記憶裝置及其資料提供方法可大幅地減少指令位址傳輸量。
Novel narrow-band-gap conjugated copolymers containing phenothiazine-arylcyanovinyl units for organic photovoltaic cell applications
(2008-07-01)
Li, Kuang-Chieh
;
Hsu, Ying-Chan
;
Lin, Jiann-T'Suen
;
Yang, Chang-Chung
;
Wei, Kung-Hwa
A series of novel narrow-band-gap copolymers (P1-P12) composed of alkyl-substituted fluorene (FO) units and six analogous mono- and bis(2-aryl-2-cyano-vinyl)- 10-hexylphenothiazine monomers (M1-M6) were synthesized by a palladium-catalyzed Suzuki coupling reaction with two different feed in ratios of FO to M1-M6 (molar ratio = 3:1 and 1:1). The absorption spectra of polymers P1-P12 exhibited broad peaks located in the UV and visible regions from 400 to 800 nm with optical band gaps at 1.55-2.10 eV, which fit near the wavelength of the maximum solar photon reflux. Electrochemical experiments displayed that the reversible p- and n-doping processes of copolymers were partially reversible, and the proper HOMO/LUMO levels enabled a high photovoltaic open-circuit voltage. As blended with [6,6]-phenyl C-61 butyric acid methyl ester (PCBM) as an electron acceptor in bulk heterojunction photovoltaic devices, narrow-band-gap polymers P1-P12 as electron donors showed significant photovoltaic performance which varied with the intramolecular donor-acceptor interaction and their mixing ratios to PCBM. Under 100 mW/cm(2) of AM 1.5 white-light illumination, the device of copolymer P12 produced the highest preliminary result having an open-circuit voltage of 0.64 V, a short-circuit current of 2.70 mA/cm(2), a fill factor of 0.29, and an energy conversion efficiency of 0.51%. (c) 2008 Wiley Periodicals, Inc.
Establishing an invar leveling calibration system
(2008-07-01)
Chen, Chun-Sung
;
Wu, Chien-Ting
;
Chang, Ming-Wei
;
Chang, Wei-Chen
;
土木工程學系
Precise height systems are widely utilized in civil engineering projects Such as high-speed railroads, and highways and bridge construction. However, highly precise height data is obtained using precise leveling. An extremely precise invar leveling rod is necessary for obtaining precise results. In this study, an automatic calibration system for invar leveling has been established by the National Measurement Laboratory (NML). The content belongs to the long scales calibration system of D17 of the NML. This system utilizes a steady frequency laser interferometer, a CCD microscopic monitor, and a precise moving mechanism. With this system, an invar rod and a mark invar leveling rod are applied to estimate uncertainty with a 95% confidence level. Uncertainty results are 22 mu m and 21 mu m for the invar leveling rods and mark invar leveling rods, respectively.
A novel compact balanced-to-unbalanced low-temperature co-fired ceramic bandpass filter with three coupled lines configuration
(2008-07-01)
Chen, Kun-Tzu
;
Chung, Shyh-Jong
;
電信工程研究所
;
Institute of Communications Engineering
This paper proposes a novel compact balanced-to-unbalanced bandpass filter. Firstly, a pre-design circuit is presented, which is composed of an inductive coupled-line bandpass filter and an out-of-phase capacitive coupled-line bandpass filter. A novel compact circuit with three coupled lines configuration, derived from the pre-design circuit, is then proposed for miniaturizing the balanced-to-unbalanced bandpass filter. A 2.4-GHz multilayer ceramic chip type balanced-to-unbalanced bandpass filter with a size of 2.0 mm x 1.2 mm x 0.7 mm is developed to validate the feasibility of the proposed structure. The filter is designed by using circuit simulation, as well as full-wave electromagnetic simulation softwares, and fabricated by the use of low-temperature co-fired ceramic technology. The measured results agree quite well with the simulated. According to the measurement results, the maximum insertion loss is 1.65 dB, the maximum in-band phase imbalance is within 3 degrees, and the maximum in-band magnitude imbalance is less than 0.32 dB.
Impact of process-induced strain on Coulomb scattering mobility in short-channel n-MOSFETs
(2008-07-01)
Chen, William P. N.
;
Su, Pin
;
Goto, K.
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
This letter provides an experimental assessment of Coulomb scattering mobility for advanced short-channel strained devices. By accurate mobility extraction under various temperatures, we examine the impact of process-induced uniaxial strain on Coulomb mobility in short-channel nMOSFETs. This letter indicates that the Coulomb mobility has significant stress dependency. Moreover, the stress sensitivity of the Coulomb mobility shows strong temperature, dependence. Because it is the interface scattering that counteracts the stress sensitivity of the bulk-impurity-limited mobility, further reducing the interface charges will be crucial to future mobility scaling.
Interactions of host IL-6 and IFN-gamma and cancer-derived TGF-beta 1 on MHC molecule expression during tumor spontaneous regression
(2008-07-01)
Hsiao, Ya-Wen
;
Liao, Kuang-Wen
;
Chung, Tien-Fu
;
Liu, Chen-Hsuan
;
Hsu, Chia-Da
Many tumors down-regulate major histocompatibility complex (MHC) antigen expression to evade host immune surveillance. However, there are very few in vivo models to study MHC antigen expression during tumor spontaneous regression. In addition, the roles of transforming growth factor beta1 (TGF-beta 1), interferon gamma (IFN-gamma), and interleukin (IL)-6 in modulating MHC antigen expression are ill understood. We previously reported that tumor infiltrating lymphocyte (TIL)-derived IL-6 inhibits TGF-beta 1 and restores natural killing (NK) activity. Using an in vivo canine-transmissible venereal tumor (CTVT) tumor model, we presently assessed IL-6 and TGF-beta involvement associated with the MHC antigen expression that is commonly suppressed in cancers. IL-6, IFN-gamma, and TGF-beta 1, closely interacted with each other and modulated MHC antigen expression. In the presence of tumor-derived TGF-beta 1, host IFN-gamma from TIL was not active and, therefore, there was low expression of MHC antigen during tumor progression. TGF-beta 1-neutralizing antibody restored IFN-gamma-activated MHC antigen expression on tumor cells. The addition of exogenous IL-6 that has potent anti-TGF-beta 1 activity restored IFN-gamma activity and promoted MHC antigen expression. IFN-gamma and IL-6 in combination acted synergistically to enhance the expression of MHC antigen. Thus, the three cytokines, IL-6, TGF-beta 1, and IFN-gamma, closely interacted to modulate the MHC antigen expression. Furthermore, transcription factors, including STAT-1, STAT-3, IRF-1, NF-kappa B, and CREB, were significantly elevated after IL-6 and IFN-gamma treatment. We conclude that the host IL-6 derived from TIL works in combination with host IFN-gamma to enhance MHC molecule expression formerly inhibited by TGF-beta 1, driving the tumor toward regression. It is suggested that the treatment of cancer cells that constitutively secrete TGF-beta 1 should incorporate anti-TGF-beta activity. The findings in this in vivo tumor regression model have potential applications in cancer immunotherapy.
PERTURBATION RESULTS RELATED TO PALINDROMIC EIGENVALUE PROBLEMS
(2008-07-01)
Chu, E. K. -W.
;
Lin, W. -W.
;
Wang, C. -S.
;
應用數學系
;
Department of Applied Mathematics
We investigate the perturbation of the palindromic eigenvalue problem for the matrix quadratic P(lambda) = lambda(2) A(1)* + lambda A(0) + A(1) with A(0), A(1) is an element of C(nxn) and A(0)* = A(0) (where * = T or H). The perturbation of eigenvalues in the context of general matrix polynomials, palindromic pencils, (semi-Schur) anti-triangular canonical forms and differentiation is discussed.
Duty phase control for single-phase boost-type SMR
(2008-07-01)
Chen, Hung-Chi
;
電控工程研究所
;
Institute of Electrical and Control Engineering
In this paper, a novel duty phase control (DPC) for single-phase boost-type switching-mode-rectifier (SMR) is developed and digitally implemented in DSP-based system. Compared to the conventional multiloop control structure with inner current loop and outer voltage loop, it is noted that there is only one voltage loop tuning the phase of predefined duty pattern (i.e. duty phase) in the proposed DPC. Due to no current loop, sampling inductor current and tracking current are unnecessary when SMRs are operated to shape the current waveform and regulate the output voltage. It implies that the single-loop DPC is simple and adaptable to the implementation with digital and analog integrated circuits. In this paper, first, the effect of the duty phase on the input current is analyzed and modeled. It shows that the sinusoidal current waveform can be naturally generated by the predefined duty pattern and the current amplitude is roughly proportional to the controllable duty phase. Then, a voltage controller is designed to regulate the dc output voltage by tuning this duty phase. Finally, some simulated and experimental results have been given to illustrate the performances of the proposed DPC.
Shallow-water gravity anomalies from satellite altimetry: Case studies in the East China Sea and Taiwan Strait
(2008-07-01)
Hwang, Cheinway
;
Hsu, Hsin-Ying
;
土木工程學系
;
Department of Civil Engineering
The differences between two global satellite altimeter-derived gravity anomaly grids over the East China Sea and the Taiwan Strait are investigated and the causes of the differences are discussed. Difference of gravity anomaly is correlated with tide model error, standard deviation of sea surface heights (SSHs) and ocean depth. We present two new SSH-derived observations of altimetry (differenced height and height slope) for gravity derivation. An iterative method for removing altimeter data outliers is used, and differenced height is found to be most sensitive to this method. For altimeter-gravity conversion, we used three altimeter-derived observations, i.e., deflection of the vertical, differenced height and height slope, in two conversion methods, i.e., the least-squares collocation (LSC) and the inverse Vening Meinesz method. Use of differenced heights in LSC produces the best result when comparing altimeter-derived and shipborne gravity anomalies. Use of land gravity data in the vicinity of coasts enhances the accuracy of altimeter-derived gravity anomalies.
產品知識、焦慮與購後失調之關係研究
(2008-07-01)
廖子賢
;
陳亭羽
;
Tze-Hsien Liao
;
Ting-Yu Chen
;
Institute of Business and Management
自1957年Festinger提出認知失調理論後，許多學者便將之應用於消費者行爲領域，從事消費者購後失調研究。由於購後失調對滿意度、品牌評價與再購意願有負面影響，因之降低購後失調是重要議題。彙整過去文獻，降低購後失調方法有：提高品牌知名度、增加購後溝通、降低消費者焦慮與提高消費者產品知識，然本研究發現，其中產品知識、焦慮、購後失調三者關係，需進一步探討。本研針對台灣北部地區某3C、家電量販店四家分店之消費者進行固定樣本兩階段問卷調查，共得有效問卷185份。經階層迴歸分析發現：情境焦慮對購後失調有顯著正向影響；特質焦慮對購後失調有顯著正向影響；特質焦慮亦會干擾情境焦慮對購後失調之影響。經簡單迴歸與複迴歸分析發現：產品知識對購後失調有顯著負向影響；產品知識對情境焦慮有顯著負向影響；情境焦慮爲產品知識與購後失調之中介變數（完全中介），換言之產品知識是透過情境焦慮，進而對購後失調有負向影響。此外，本研究亦發現，購買決策涉入對購後失調有顯著正向影響；消費者之產品知覺價值、品牌知名度對購後失調有顯著負向影響。
Talk burst control for Push-to-talk over Cellular
(2008-07-01)
Tsai, Meng-Hsun
;
Lin, Yi-Bing
;
資訊工程學系
;
Department of Computer Science
Push-to-talk over Cellular (PoC) is a "walkie-talkie"-like service designed for mobile networks. In this service, the speak permission is arbitrated through the talk burst control (TBC) mechanism. This paper proposes an analytic model to study the performance of the TBC mechanism with queueing and without queueing. This analytic model is validated against simulation experiments. Through numerical examples, our study provides guidelines to set up the parameters for PoC service.
楓葉造反
(2008-07-01)
管管
RNALogo: a new approach to display structural RNA alignment
(2008-07-01)
Chang, Tzu-Hao
;
Horng, Jorng-Tzong
;
Huang, Hsien-Da
;
生物科技學系
;
生物資訊及系統生物研究所
Regulatory RNAs play essential roles in many essential biological processes, ranging from gene regulation to protein synthesis. This work presents a web-based tool, RNALogo, to create a new graphical representation of the patterns in a multiple RNA sequence alignment with a consensus structure. The RNALogo graph can indicate significant features within an RNA sequence alignment and its consensus RNA secondary structure. RNALogo extends Sequence logos, and specifically incorporates RNA secondary structures and mutual information of base-paired regions into the graphical representation. Each RNALogo graph is composed of stacks of letters, with one stack for each position in the consensus RNA secondary structure. RNALogo provides a convenient and high configurable logo generator. An RNALogo graph is generated for each RNA family in Rfam, and these generated logos are accumulated into a gallery of RNALogo. Users can search or browse RNALogo graphs in this gallery to receive additional perspectives of known RNA families. RNALogo is now available at: http://rnalogo.mbc.nctu.edu.tw/.
Productive public expenditures, expectation formations and nonlinear dynamics
(2008-07-01)
Chen, Hung-Ju
;
Li, Ming-Chia
;
應用數學系
;
Department of Applied Mathematics
In this paper, we investigate the dynamic properties of an overlapping generations' model with capital accumulation and publicly funded inventions under three different expectations: perfect foresight, myopic expectations and adaptive expectations. We show that considering productive public expenditures in the model will increase the dimension of the dynamical system. To study the dynamic behavior of a high-dimensional dynamical system, we focus on the case when the elasticity of publicly funded invention to output is small and approximate the system by using a one-dimensional dynamical system. This approximation method provides an efficient way to rigorously prove the existence of chaos in high-dimensional dynamical systems. We show that when agents are perfectly foresighted, there exists a unique, nontrivial steady state which is a global attractor. Cycles or even chaos may occur under myopic and adaptive expectations when the inter-temporal elasticity of substitution of consumption is large enough. Furthermore, we find that the impact of fiscal policy is sensible to the expectation formation. (C) 2008 Elsevier B.V. All rights reserved.
Homogenization of the Maxwell's system for conducting media
(2008-07-01)
Jiang, Jiann-Sheng
;
Lin, Chi-Kun
;
Liu, Chi-Hua
;
應用數學系
;
Department of Applied Mathematics
This paper is devoted to the study of the memory effect induced by homogenization of the Maxwell system for conducting media. The memory kernel is described by the Volterra integral equation. Furthermore, it can be characterized explicitly in terms of Young's measure, and the kinetic formulation of the homogenized equation is also obtained. The kinetic formulation allows us to obtain the homogenization of the energy density and the associated conservation law with the Poynting vector. The interesting interaction phenomenon of the microscopic and macroscopic scales is also discussed and the memory effect explains qualitatively something about irreversibility.
Effect of yttria on interfacial reactions between titanium melt and hot-pressed yttria/zirconia composites at 1700 degrees C
(2008-07-01)
Lin, Chien-Cheng
;
Chang, Yao-Wen
;
Lin, Kun-Lin
;
Lin, Kun-Fung
;
材料科學與工程學系
Various Y(2)O(3)/ZrO(2) samples were fabricated by hot pressing, whereby Y(2)O(3) was mutually dissolved or reacted with ZrO(2) as a solid solution or Zr(3)Y(4)O(12). Hot-pressed samples were allowed to react with Ti melt at 1700 degrees C for 10 min in argon. Microstructural characterization was conducted using X-ray diffraction and analytical electron microscopy. The Y(2)O(3)/ZrO(2) samples became more stable with increasing Y(2)O(3) because Y(2)O(3) was hardly reacted and dissolved with Ti melt. The incorporation of more than 30 vol% Y(2)O(3) could effectively suppress the reactions in the Ti side, where only a very small amount of alpha-Ti and beta'-Ti was found. When ZrO(2) was dissolved into Ti on the zirconia side near the original interfaces, Y(2)O(3) reprecipitated in the samples containing 30%-70 vol% Y(2)O(3), because the solubility of Y(2)O(3) in Ti was very low. In the region far from the original interface, alpha-Zr, Y(2)O(3), and/or residual Zr(3)Y(4)O(12) were found in the samples containing more than 50 vol% Y(2)O(3) and the amount of alpha-Zr decreased with increasing Y(2)O(3).
Clarification and calibration of reflection coefficient for electrical conductivity measurement by time domain reflectometry
(2008-07-01)
Lin, C. -P.
;
Chung, C. -C.
;
Huisman, J. A.
;
Tang, S. -H.
;
土木工程學系
Measurement of electrical conductivity by time domain reflectometry (TDR) requires knowledge of the source step voltage, which is often implicitly accounted for in the measured reflection coefficient. Errors may arise, however, from imperfect amplitude calibration when transforming the voltage signal into the reflection coefficient signal. This instrument error was identified as a considerable source of error in addition to cable resistance for TDR electrical conductivity measurements. The effect of the instrument error due to imperfect amplitude calibration was theoretically examined by the direct current circuit model and experimentally verified. The instrument error resulted in an overestimation of electrical conductivity while the cable resistance led to an underestimation. We clarified that the series resistors model for correction of cable resistance is accurate if the measured reflection coefficient is corrected for the instrument error. A calibration (correction) method for the measured reflection coefficient was proposed to account for both the instrument error and the effect of cable resistance, leading to a simple, accurate, and theoretically sound procedure for TDR electrical conductivity measurements.
Temperature-dependent capacitance characteristics of RF LDMOS transistors with different layout structures
(2008-07-01)
Hu, Hsin-Hui
;
Chen, Kun-Ming
;
Huang, Guo-Wei
;
Chen, Ming-Yi
;
Cheng, Eric
In this letter, the capacitance characteristics of RF LDMOS transistors with different temperatures and layout structures were studied. In a conventional fishbone structure, the peaks in capacitances decrease with increasing temperature. For the ring structure, two peaks in a capacitance-voltage curve have been observed at high drain voltages due to the additional corner effect. in addition, peaks in gate-to-source/body capacitance decrease and peaks in gate-to-drain capacitance increase with increasing temperature at high drain voltages. By analyzing the effects of temperature on threshold voltage, quasi-saturation current, and drift depletion capacitance, the variations of capacitances with temperature were investigated.