Browsing by Issue Date, starting with "2006-06-15"

Now showing 1 - 20 of 63166

Common stabilizers for linear control systems in the presence of actuators outage
(2006-06-15)
Liang, Yew-Wen
;
Liaw, Der-Cherng
;
電控工程研究所
;
Institute of Electrical and Control Engineering
Issue concerning the existence of common stabilizers for a linear control system experiences actuators. outage are presented. The possible outage of actuators examined in this study are not restricted to a pre-specified set. By finding Common quadratic-type Lyapunov functions. we obtain sufficient conditions for the existence of common stabilizers. For cases of which all the possible failed actuators belonged to a pre-specified set. the results presented in this paper agree with those obtained by Veillette in 1995. The control gain of common stabilizer for non-nested case is explicitly derived to guarantee system stability. A simplified checking condition for the existence of common stabilizers is also obtained for the extreme case when only single actuator can normally operate. (c) 2005 Elsevier Inc. All rights reserved.
管管作品三首
(2006-06-15)
管管
Epoxy/polyhedral oligomeric silsesquioxane nanocomposites from octakis(glycidyidimethylsiloxy)octasilsesquioxane and small-molecule curing agents
(2006-06-15)
Liu, YL
;
Chang, GP
;
Hsu, KY
;
Chang, FC
;
應用化學系
Epoxy/polyhedral oligomeric silsesquioxane (POSS) nanocomposites were obtained from octakis(glycidyldimethylsiloxy)octasilsesquioxane (OG) and diglycidyl ether of bisphenol A cured with small-molecule curing agents of diethylphosphite (DEP) and dicyandiamide (DICY). An increase in the POSS contents of the nanocomposites and an improvement in the nanocomposite homogeneity were observed with the use of the small-molecule curing agents. Phosphorus in DEP and nitrogen in DICY also performed synergism with POSS for thermal stability enhancement and flammability improvement in the nanocomposites. The nanocomposites possessing high OG contents exhibited good thermal stability, improved flammability, and high storage moduli. (c) 2006 Wiley Periodicals, Inc.
管管作品三首
(2006-06-15)
管管
Tool replacement for production with a low fraction of defectives
(2006-06-15)
Pearn, WL
;
Hsu, YC
;
Wu, CW
;
工業工程與管理學系
;
Department of Industrial Engineering and Management
In manufacturing industry, the tool replacement cost is, in many cases, a significant portion of the production cost. Early tool replacement increases the production cost. Overdue tool replacement, however, results in poor production quality. Accordingly, improving production quality while maintaining a low production cost is essential. The index C-pk is regarded as a yield-based index. For a fixed C-pk value, the production yield and fraction of defectives can be calculated. In this paper, we present an analytical approach using C-pk to determine the optimal tool replacement time. An accurate process capability must be calculated, particularly when the data contain assignable cause variation. Tool wear is a dominant and inseparable component in many machining processes (a systematic assignable cause), and ordinary capability measures become inaccurate because process data are contaminated by the assignable cause variation. Considering process capability changes dynamically, an estimator of C-pk is investigated. The closed form of the exact sampling distribution is derived. An effective tool management procedure for determining the optimal tool replacement time is presented for processes with a low fraction of defectives. For illustrative purposes, an application example involving tool wear is presented.
管管作品三首
(2006-06-15)
管管
管管作品三首
(2006-06-15)
管管
Fast solvers for 3D Poisson equations involving interfaces in a finite or the infinite domain
(2006-06-15)
Lai, MC
;
Li, ZL
;
Lin, XB
;
應用數學系
;
Department of Applied Mathematics
In this paper, numerical methods are proposed for Poisson equations defined in a finite or infinite domain in three dimensions. In the domain, there can exists an interface across which the source term, the flux, and therefore the solution may be discontinuous. The existence and uniqueness of the solution are also discussed. To deal with the discontinuity in the source term and in the flux, the original problem is transformed to a new one with a smooth solution. Such a transformation can be carried out easily through an extension of the jumps along the normal direction if the interface is expressed as the zero level set of a three-dimensional function. An auxiliary sphere is used to separate the infinite region into an interior and exterior domain. The Kelvin's inversion is used to map the exterior domain into an interior domain. The two Poisson equations defined in the interior and the exterior written in spherical coordinates are solved simultaneously. By choosing the mesh size carefully and exploiting the fast Fourier transform, the resulting finite difference equations can be solved efficiently. The approach in dealing with the interface has also been used with the artificial boundary condition technique which truncates the infinite domain. Numerical results demonstrate second order accuracy of our algorithms. (c) 2005 Elsevier B.V. All rights reserved.
A recursively construction scheme for super fault-tolerant hamiltonian graphs
(2006-06-15)
Chen, Y-Chuang
;
Hsu, Lih-Hsing
;
Tan, Jimmy J. M.
;
資訊工程學系
;
Department of Computer Science
For the interconnection network topology, it is usually represented by a graph. When a network is used. processors and/or links faults may happen. Thus, it is meaningful to consider faulty networks, We consider k-regular graphs in this paper. We define a k-regular hamiltonian and hamiltonian connected graph G is super fault-tolerant hamiltonian if G remains hamiltonian after removing at most k - 2 vertices and/or edges and remains hamiltonian connected after removing at most k - 3 vertices and/or edges. A Super fault-tolerant hamiltonian graph has a certain optimal flavor with respect to the fault tolerant hamiltonicity and fault-tolerant hamiltonian connectivity. The aim of this paper is to investigate a construction scheme to construct various super fault-tolerant hamiltonian graphs. Along the way. the recursire circulant graph is a special case of our construction scheme. and the super fault-tolerant hamiltonian property of recursive circulant graph is obtained. (c) 2005 Elsevier Inc. All rights reserved.
管管作品三首
(2006-06-15)
管管
Architecture of an embedded internet robot system controlled by brain waves
(2006-06-15)
Wu, Li-Wei
;
Liao, Hsien-Cheng
The present invention discloses an architecture of an embedded internet robot system controlled by brain waves, wherein the brain-computer interface and the internet robot system cooperate with the alertness level detection technology and the instruction translation technology, and thereby, the user can control a distal-end robot purely via consciousness activities and can interact with the environment as if there were an entity representing the user's consciousness appearing in the distal end. The seriously disabled person can regain his expressive ability via the present invention. Further, the present invention can also be applied to a multi-player interactive game system.
Bicriteria scheduling in a two-machine permutation flowshop
(2006-06-15)
Lin, BMT
;
Wu, JM
;
資訊管理與財務金融系註：原資管所+財金所
;
Department of Information Management and Finance
In this paper we consider a production scheduling problem in a two-machine flowshop. The bicriteria objective is a linear combination or weighted sum of the makespan and total completion time. This problem is computationally hard because the special case concerning the minimization of the total completion time is already known to be strongly NP-hard. To find an optimal schedule, we deploy the Johnson algorithm and a lower bound scheme that was previously developed for total completion time scheduling. Computational experiments are presented to study the relative performance of different lower bounds. While the best known bound for the bicriteria problem can successfully solve test cases of 10 jobs within a time limit of 30 min, under the same setting our branch-and-bound algorithm solely equipped with the new scheme can produce optimal schedules for most instances with 30 or less jobs. The results demonstrate the convincing capability of the lower bound scheme in curtailing unnecessary branching during problem-solving sessions. The computational experience also suggests the practical significance and potential implications of this scheme.
Effect of growth rate on the composition fluctuation of InGaAsN/GaAs single quantum wells
(2006-06-15)
Chen, JF
;
Hsiao, RS
;
Hsieh, PC
;
Wang, JS
;
Chi, JY
Effect of growth rate on the composition fluctuation is investigated in In0.34Ga0.66As0.98N0.02/GaAs single quantum wells (QWs) by photoluminescence (PL), transmission electron microscopy, and admittance spectroscopy. In an InGaAsN layer grown at a normal growth rate, the PL spectra show a low-energy bump at the tail of an InGaAsN emission, suggesting the presence of composition fluctuation. Lowering the growth rate degrades the composition fluctuation by segregating into bimodal phases of an InGaAsN and InGaAs-rich phase. Further lowering the growth rate leads to a three-dimensional growth and enhances the InGaAs-rich phase. The carrier distribution for the InGaAsN layer grown at the normal rate shows a carrier bump at the tail of a strong accumulation peak, suggesting the presence of an electron state below the QW ground state. The admittance spectroscopy shows that the activation energy (32 meV) of this electron state is comparable to the energy separation (30 meV) between the InGaAsN emission and the low-energy bump, and thus it is possible that the composition fluctuation actually induces an electron state closely below the QW ground state. (c) 2006 American Institute of Physics.
管管作品三首
(2006-06-15)
管管
Optical and electrical transport properties of facing-target sputtered Al doped ZnO transparent film
(2006-06-15)
Li, ZQ
;
Zhang, DX
;
Lin, JJ
;
電子物理學系
;
物理研究所
Al doped zinc oxide thin film was prepared by dc facing-target sputtering method and its structural, optical, and electrical transport properties have been investigated. The average transmittance of the films is greater than 90% in the wavelength region of 450-700 nm while the resistivity is as high as 3x10(-3) Omega cm. The band gap energy derived from the transmission data is 3.76 eV, which is higher than that of pure ZnO thin film. This band gap growth phenomenon cannot be explained in terms of the Burstein-Moss effect. The resistivity and Hall effect measurements suggest that the interaction between the charge carriers and phonons plays a key role in the electrical transport properties of the film between 60 and 300 K. The film exhibits negative magnetoresistance at low temperatures, which can be well described by a semiempirical expression that takes into account the third order s-d exchange Hamiltonians describing a negative part and a two-band model for positive contribution.
Development of a parallel Poisson's equation solver with adaptive mesh refinement and its application in field emission prediction
(2006-06-15)
Hsu, KH
;
Chen, PY
;
Hung, CT
;
Chen, LH
;
Wu, JS
A parallel electrostatic Poisson's equation solver coupled with parallel adaptive mesh refinement (PAMR) is developed in this paper. The three-dimensional Poisson's equation is discretized using the Galerkin finite element method using a tetrahedral mesh. The resulting matrix equation is then solved through the parallel conjugate gradient method using the non-overlapping subdomain-by-subdomain scheme. A PAMR module is coupled with this parallel Poisson's equation solver to adaptively refine the mesh where the variation of potentials is large. The parallel performance of the parallel Poisson's equation is studied by simulating the potential distribution of a CNT-based triode-type field emitter. Results with similar to 100 000 nodes show that a parallel efficiency of 84.2% is achieved in 32 processors of a PC-cluster system. The field emission properties of a single CNT triode- and tetrode-type field emitter in a periodic cell are computed to demonstrate their potential application in field emission prediction. (c) 2006 Elsevier B.V. All rights reserved.
隨機存取記憶體陣列結構
(2006-06-16)
鄭東栓
;
黃威
本發明提供一種隨機存取記憶體陣列結構，其係將一隨機存取記憶體陣列結構分成複數個資料區塊，每一資料區塊以陣列方式排列，且每一資料區塊連接有一及閘及電源閘，利用一編碼裝置使一數據資料進行儲存或讀取動作。本發明能有效使電路減少漏電流的產生，進而大幅降低動態功率之消耗。
助銲劑
(2006-06-16)
徐享文
;
黃和悅
;
曾光宏
;
林仁治
;
張肇芳
一種助銲劑，包含有一基質以及一活化添加物：基質係為氧化鉬，而活化添加物係選自氧化鐵、氧化矽，以及碳酸鎂所組成之群組；藉此，本發明可應用於碳鋼材料之銲接加工，提高銲接過程的銲道熔接深度，達到節省加工時間，減少整體製造成本之目的。
近紅外波段飛秒雷射在非晶矽退火的應用方法
(2006-06-16)
謝嘉民
;
陳尊豪
;
戴寶通
;
王怡超
;
潘犀靈
本發明提供一種近紅外波段飛秒雷射在非晶矽退火的應用方法，其係利用紅外波段的超快鈦藍寶石雷射(Ultrafast Ti：Sapphire Laser)進行非晶矽的飛秒雷射退火(Femtosecond Laser Annealing, FLA)，樣品表面被超短脈衝照射的時候，超高的瞬時功率使得樣品表面發生對光子能量的非線性吸收並產生高密度的電漿，使得非晶矽達到融熔狀態。飛秒雷射退火藉由連續掃瞄的幫助可以將非晶矽再結晶成多晶矽，所得到的晶粒尺寸約可達0.8μm，再結晶過程所需要的雷射能量密度僅約45mJ／cm^2。因此本發明提供一種近紅外波段飛秒雷射在非晶矽退火的應用，可得到晶粒尺寸大的多晶矽，較佳之表面平整度，再結晶過程所需雷射能量密度低，可增進製程效率及電晶體的載子遷移率。
以腦電波控制的嵌入式網路機器人架構
(2006-06-16)
吳立偉
;
廖憲正
本發明係揭露一種以腦電波控制的嵌入式網路機器人架構，其係使用腦機界面(BCI)技術以及網路機器人(Internet Robot Agent)架構為基礎，並配合腦電波警覺程度偵測與指令轉譯技術，讓使用者可以藉由單純的意識活動來控制遠端機器人，進而與環境達到互動，如同根據使用者意識在遠端建立一可代表使用者之實體。此一系統架構能使重度殘障者擁有對環境的表達能力，亦可應用於多人連線之互動遊戲系統中。