Browsing by Issue Date, starting with "2003-10-01"

Now showing 1 - 20 of 72311

Realization of transmission zeros in combline filters using an auxiliary inductively coupled ground plane
(2003-10-01)
Tang, CW
;
Lin, YC
;
Chang, CY
;
電信工程研究所
;
Institute of Communications Engineering
The out-band transmission zeros of the multilayer low-temperature co-fired ceramic bandpass filter are studied in this paper. The design target of this filter, with the passband between 2.3-2.65 GHz (the true application is 2.4-2.483 GHz), is to reject the local oscillator and image signals and, in the mean time, to suppress the harmonic frequency. This filter is a modified three-pole combline filter, which can easily achieve a high rejection rate and low insertion loss. The source-load coupling capacitor incorporation with cross-coupling grounding inductors can generate three transmission zeros. By properly adjusting the inductance values of the inductors between three resonators and ground can easily manipulate the transmission zero at a high-side skirt to suppress the harmonic frequency. The measured results match well with the electromagnetic simulation that evidences the feasibility of the proposed design.
Relationship between protein structures and disulfide bonding patterns
(2003-10-01)
Chuang, CC
;
Chen, CY
;
Yang, JM
;
Lyu, PC
;
Hwang, JK
We found that that disulfide-bonding patterns can be used to discriminate structure similarity. Our method, based on the hierarchical clustering scheme, is applicable to proteins with two or more disulfide bonds and is able to detect the structural similarities of proteins of low sequence identities (<25%). Our results show the surprisingly close relationship between disulfide-bonding patterns and proteins structures. Our findings should be useful in protein structure modeling. (C) 2003 Wiley-Liss, Inc.
Synthesis and characterization of needlelike apatitic nanocomposite with controlled aspect ratios
(2003-10-01)
Liou, SC
;
Chen, SY
;
Liu, DM
;
材料科學與工程學系
;
Department of Materials Science and Engineering
Calcium-deficient apatitic (cd-HA) crystals with core-shell nanostructure with needlelike shape, 5-10nm in diameter and 2080 nm in length. were prepared via an in situ formation in the presence of polyacrylic acid (PAA) under aqueous solution of different pH values. ranging from 9 to 11. Nanostructure of the resulting crystals showing a core-shell configuration with a thin layer of PAA shell of about I rim thickness was investigated. Aspect ratio (AR) of the needlelike composite was found to depend on the concentration of the PAA and solution pH. At lower solution pH crystal growth was inhibited, i.e., leading to a decreased AR, with increase of PAA concentration. while an increased AR was detected at higher solution pH, suggesting a preferential growth of the cd-HA nanocrystals. Mechanism of such preferential growth was tentatively proposed and is suggested to correct PAA adsorption alone the long axis of the needlelike nanoparticles. (C) 2003 Elsevier Science Ltd. All rights reserved.
管管作品六首
(2003-10-01)
管管
A histogram-based moment-preserving clustering algorithm for video segmentation
(2003-10-01)
Lo, CC
;
Wang, SJ
;
資訊管理與財務金融系註：原資管所+財金所
;
Department of Information Management and Finance
Video segmentation is the first step of creating video indices for a video retrieval system. A segmentation algorithm is used to identify shots from video data. In this paper, we propose a histogram-based moment-preserving (HBMP) clustering algorithm for segmenting video data. This algorithm is a hybrid of the shot change detection approach and the clustering approach. The computational results indicate that the proposed algorithm is both effective and efficient with respect to various types of video sequence. (C) 2003 Elsevier B.V. All rights reserved.
Three-frequency chaotic instability in soft-aperture Kerr-lens mode-locked laser around 1/3-degenerate cavity configuration
(2003-10-01)
Lin, JH
;
Hsieh, WF
;
光電工程學系
;
Department of Photonics
The quasi-periodic route to chaos from a three-frequency interaction was experimentally observed when the soft-aperture Kerr-lens mode-locked Ti:sapphire laser was operated in a cavity configuration that was around 1/3-degenerate, with non-zero group velocity dispersion. When the pump beam was smaller than the cold cavity beam, the laser oscillated among three frequencies, resulting in the modulation of phase-locked longitudinal modes. Increasing the pump power caused the nonlinear interaction of the three frequencies to induce a combination tones due to nonlinear gain and Kerr nonlinearity. Further secondary beating of these combinations tones at even higher pumping caused the system to become chaotic. Starting from the period-3 pulses in the 1/3-degenerate configuration, the quasi-periodic route to chaos was also observed when the configuration was tuned slightly away from degeneracy. (C) 2003 Elsevier B.V. All rights reserved.
Closure to "Passive earth pressure with critical state concept" by Yung-Show Fang, Ying-Chieh Ho, and Tsang-Jiang Chen
(2003-10-01)
Fang, YS
;
Ho, YC
;
Chen, TJ
;
土木工程學系
;
Department of Civil Engineering
A case study in the design of BTO/CTO shop floor control system
(2003-10-01)
Chen, RS
;
Lu, KY
;
Yu, SC
;
Tzeng, HW
;
Chang, CC
Although computerized information systems are conventionally used to control production, applying a manual approach and improper logistical assignments typically reduces operating efficiency and increases customer service response time. Satisfying the requirements of remaining competitiveness in the current marketplace, such as offering build-to-order (BTO) or configuration-to-order (CTO) services is difficult. This study presents an integrated information system for use in shop floor controlling systems (SFCS) for kitting parts, producing goods, packing finished goods and distributing them, to enhance the performance of the BTO/CTO production system. Several information technologies and devices, such as barcode system, the electronic pick-to-light picking system, electronic Kanban (eKanban), and others are adopted to support the relevant logistics. A personal computer (PC) manufacturer is used to demonstrate the proposed system. The findings of the study reveal that the proposed information system can respond to the status of the production line in real time. This responsiveness can help the production controller to make a suitable decision and quickly meet the requirements of the BTO/CTO production system. (C) 2003 Elsevier Science B.V. All rights reserved.
Wide-sense nonblocking multicast Log(2) (N, m, p) networks
(2003-10-01)
Hwang, FK
;
Lin, BC
;
應用數學系
;
Department of Applied Mathematics
Recently, Tscha and Lee proposed a fixed-size window algorithm for the multicast Log(2) (N, 0, p) network and expressed a desire to see its extension to the Log(2) (N, m, p) network. Later, Kabacinski and Danilewiez generalized the fixed-size window to variable size to improve the results. In this paper, we further. extend the variable-size results from the Log(2) (N, 0, p) network to Log(2) (N, m, p). Note that this extension is difficult since each link in the channel graph of Log(2) (N, 0, p) has the same blocking effect, but not so in Log(2) (N, m, p). We also determine the optimal window size and optimal m.
Simulation analysis and experimental verification of UV-LIGA process for high-aspect-ratio Ni-Fe micro-mold insert
(2003-10-01)
Yeh, YM
;
Tu, GC
;
Fu, MN
;
材料科學與工程學系
;
Department of Materials Science and Engineering
UV (ultra violet)-LIGA (a German acronym for lithographic, gavanoformung, abformung), a low-cost microcomponent manufacturing technology for micro-electromechanical systems (MEMS), combines the UV patterning of thick photoresist layers with the molding of the resulting patterns by electroforming. It enables mass production of microcomponents using microinjection molding or hot embossing technology. This paper addresses the characteristics of the flow field and the mass transfer effect during micro-electroforming processes. A micro-electroforming experiment is conducted and a simulation is performed to determine optimal conditions for fine surface forming by micro-electroforming. Results show that a smaller diameter of a hole corresponds to poorer plating bath transfer. Plating bath can be replenished by increasing the rotation speed of the electrodes. However, mass transfer is still limited in holes with a high aspect ratio. The theoretical results of simulation analysis were verified by conducting practical electroforming experiments.
High reflectivity distributed Bragg reflectors for 1.55 mu m VCSELs using InP/airgap
(2003-10-01)
Tsai, JY
;
Lu, TC
;
Wang, SC
;
光電工程學系
;
Department of Photonics
A high reflecting InP/airgap distributed Bragg reflector (DBR) using InGaAs as sacrificial layers is demonstrated. The 3-pair InP/airgap DBR is formed by etching the InGaAs layers of the MOCVD grown InP/InGaAs structure using H2SO4 solution. A rigid and stable InP/airgap DBR with a peak reflectivity of 99.9% at 1.54 mum and a stopband width of about 200 nm is achieved. (C) 2003 Elsevier Ltd. All rights reserved.
Low-temperature-processed polycrystalline silicon thin-film transistors using a new two-step crystallization technique
(2003-10-01)
Fan, CL
;
Chen, MC
;
Chang, Y
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
Low-temperature-processed (LTP) Polycrystalline silicon thin-film transistors (poly-Si TFTs) fabricated with a poly-Si film crystallized by a new two-step crystallization (NTSC) technique were investigated. The NTSC is characterized by the combination of excimer-laser-induced formation of nucleation centers and short-time low- temperature furnace annealing to create clear crystalline grains with very few in-grain defects. The LTP poly-Si TFTs fabricated with a NTSC poly-Si film not only exhibit better performance but also significantly shorten the crystallization time (about 6 h at 600degreesC) as compared to those fabricated using conventional solid phase crystallization (about 20 h or longer at 600degreesC).
管管作品六首
(2003-10-01)
管管
An empirical study of the Taiwan National Quality Award causal model
(2003-10-01)
Su, CT
;
Li, SC
;
Su, CH
;
工業工程與管理學系
;
Department of Industrial Engineering and Management
In this study, the Taiwan National Quality Award (TNQA) is discussed in terms of a modelling approach for the first time since it was founded in 1990. A survey instrument involving 105 questions extracted from the 2001 TNQA criteria serves to measure the content of the TNQA. A causal model is proposed to reveal the relationships among TNQA categories. Structural equation modelling (SEM) is used to analyse the model and estimate path coefficients among TNQA categories. The statistical results show that many of the hypothesized causal relationships in the TNQA model are statistically significant. From path coefficients, the category of Leadership has a strong influence on that of Information Management. Simultaneously, Information Management has impacts on other TNQA system categories. Information Management is confirmed as an internal driver of TNQA system categories. Both Leadership and Innovation and Strategic Management show direct influence on Business Results. Generally, several conclusions are made as follows. First, the assumption that the TNQA model is recursive is supported by statistical results. Secondly, the prior theory of this causal model that Leadership is a driver of the system, which creates results is confirmed. Thirdly, the final causal model also represents an excellent model of business performance, which can predict expected results through system paths. Other conclusions and findings are discussed in the study.
Direct observation of long-term durability of superconductivity in YBa2Cu3O7-Ag2O composites
(2003-10-01)
Lin, JJ
;
Lin, YH
;
Huang, SM
;
Lee, TC
;
Chen, TM
We report direct observation of long-term durability of superconductivity of several YBa2Cu3O7-Ag2O composites that were first prepared and studied almost fourteen years ago [J. J. Lin et al.: Jpn. J. Appl. Phys. 29 (1990) 497]. Remeasurements performed recently on both resistances and magnetizations indicate a sharp critical transition temperature at 91 K. We also find that such long-term environmental stability of high-temperature superconductivity can only be achieved in YBa2Cu3O7 with Ag2O addition, but not with pure Ag addition.
Nonlinear analysis of axially loaded concrete-filled tube columns with confinement effect
(2003-10-01)
Hu, HT
;
Huang, CS
;
Wu, MH
;
Wu, YM
;
土木工程學系
Proper material constitutive models for concrete-filled tube (CFT) columns are proposed and verified by the nonlinear finite element program ABAQUS against experimental data. The cross sections of the CFT columns in the numerical analysis are categorized into three groups, i.e., circular section, square section, and square section stiffened by reinforcing ties. Via the numerical analyses, it is shown that for circular CFT columns, the tubes can provide a good confining effect to the concrete especially when the width-to-thickness ratio D/t is small (say D/t<40). For square CFT columns, the tubes do not provide a large confining effect to the concrete especially when the width-to-thickness ratio B/t is large (say B/t>30). The confining effect of square CFT columns with reinforcing ties is enhanced by the use of reinforcing ties especially when the tie spacing is small and the tie number (or tie diameter) is large.
Modeling and design of the high performance step SOI-LIGBT power devices by partition mid-point method
(2003-10-01)
Chang, FL
;
Lin, MJ
;
Lee, GY
;
Chen, YS
;
Liaw, CW
In this paper, a partition method is proposed to Study the high voltage devices with the step doping profile for the first time. It has been proposed that its breakdown voltage can be approached to that of the linearly graded devices with similar forward voltage drop (V-cc). In addition, by this method, the breakdown voltage can be deduced and its corresponding issue location is also fingered out in the step drift region. Furthermore. in order to reduce the undesirable additional masks, the degraded factor (D) is developed to obtain better performance with the least number of frames. Eventually, a 660 V step analytical results are compared with a 606.6 V MEDICI Simulation and this shows that the partition method is very effective. (C) 2003 Elsevier Ltd. All rights reserved.
The role of nitrogen in carbon nanotube formation
(2003-10-01)
Lin, CH
;
Chang, HL
;
Hsu, CM
;
Lo, AY
;
Kuo, CT
To examine the role of nitrogen, Co- and Ni-coated substrates were pretreated with three different gas compositions to compare the pretreated catalyst surfaces; the Fe, Co and Ni foils were subjected to carbon nanotube (CNT) growth experiments with CH4/H-2 and CH4/N-2 as source gases; the catalyst pretreatment plus the CNT growth experiments on Co- and Ni-coated Si substrates were carried out using both microwave plasma chemical vapor deposition and electron cyclotron resonance chemical vapor deposition (ECR-CVD) under different nitrogen-containing gases. The results show that the role of nitrogen may be summarized as follows: by comparing with hydrogen plasma, the bombardment energy of nitrogen plasma is greater. Therefore, the presence of nitrogen during CNT growth can keep the front catalyst surface clean and active to prolong surface passivation to enhance carbon bulk diffusion. The higher temperature due to higher bombardment energy of nitrogen plasma can promote agglomeration effects during catalyst pretreatment and the initial stage of CNT growth to produce larger size nano-particles. The presence of nitrogen is a favorable condition for formation of the bamboo-like CNTs, but not a necessary condition. Another favorable condition for formation of the bamboo-like CNTs is to deposit CNTs by ECR-CVD. (C) 2003 Elsevier Science B.V. All rights reserved.
Design and implementation of new object-oriented rule base management system
(2003-10-01)
Lin, YT
;
Tseng, SS
;
Tsai, CF
;
資訊工程學系
;
Department of Computer Science
In this work, a knowledge model, new object-oriented rule model (NORM), is proposed based on the concept of learning and thinking behaviors of human. It provides high maintainability and reusability through the object-oriented concept. There are four basic relations between knowledge concepts defined in NORM: Reference, Extension-of, Trigger and Acquire. These relations are helpful in describing the cooperation of the different knowledge concepts. In addition, we describe how to construct and maintain a knowledge base under this model. A NORM knowledge modeled rule base system platform, DRAMA, is also introduced and applied in this paper. In order to illustrate the capability of NORM knowledge model, a learning management system using DRAMA to infer the knowledge for selecting appropriate learning content for different student is designed and implemented. (C) 2003 Elsevier Ltd. All rights reserved.
Characterization of temperature dependence for HfO2 gate dielectrics treated in NH3 plasma
(2003-10-01)
Wang, JC
;
Shie, DC
;
Lei, TF
;
Lee, CL
;
電子工程學系及電子研究所
For the first time, the characteristics and temperature dependence of electrical properties for ultrathin HfO2 gate dielectrics treated in NH3 plasma after deposition were investigated. After this treatment, significant nitrogen incorporation at the HfO2/silicon interface (interfacial layer) was examined by Auger electron spectroscopy. Moreover, the formation of Hf-N bonding and the suppression of Hf-Si bonding were observed from electron spectroscopy for chemical analysis spectra. The activation energy of charge trapping reflected in the current-voltage characteristics was effectively reduced, which led to improved hysteresis and its weaker temperature dependence in HfO2 gate dielectrics treated in NH3 plasma. (C) 2003 The Electrochemical Society.