Browsing by Author "CHANG, CH"

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A CONNECTIONIST APPROACH FOR THRESHOLDING
(1992)
CHANG, CC
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CHANG, CH
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HWANG, SY
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資訊工程學系
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Department of Computer Science
A UNIFIED 3-D MOBILITY MODEL FOR THE SIMULATION OF SUBMICRON MOS DEVICES
(1993-04-01)
YANG, JJ
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CHUNG, SSS
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CHANG, CH
;
LEE, GH
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電子工程學系及電子研究所
A calibrated and physically based mobility model is developed for three-dimensional simulation of submicron metal-oxide-semiconductor (MOS) devices, in which the inversion layer mobility is emphasized. This inversion layer mobility can be generalized into a local form, i.e., expressed as functions of the local electric field at each grid point, so that it is well suited for device simulation. The resulting 3-D mobility model accurately characterizes the significant physical scattering effects including the Coulomb screening effect, quantum channel broadening effect, surface roughness scattering, structure-induced lateral surface scattering and velocity saturation limited effects. Results show that this new model can be incorporated into device simulators for accurately predicting drain currents of submicron LDD MOS devices. Moreover, the results compare more favorably with the experimental data than do those for other reported models.
GAIN MARGIN AND PHASE MARGIN ANALYSIS OF A NUCLEAR-REACTOR CONTROL-SYSTEM WITH MULTIPLE TRANSPORT LAGS
(1989-08-01)
CHANG, CH
;
HAN, KW
;
交大名義發表
;
電控工程研究所
;
National Chiao Tung University
GAIN MARGINS AND PHASE MARGINS FOR CONTROL-SYSTEMS WITH ADJUSTABLE-PARAMETERS
(1990-05-01)
CHANG, CH
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HAN, KW
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電控工程研究所
;
Institute of Electrical and Control Engineering
GAIN MARGINS AND PHASE MARGINS FOR MULTIVARIABLE CONTROL-SYSTEMS WITH ADJUSTABLE-PARAMETERS
(1991-08-01)
TAO, CS
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CHANG, CH
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HAN, KW
;
交大名義發表
;
National Chiao Tung University
This paper presents a method for finding the boundaries of gain margins and phase margins of multivariable control systems with adjustable parameters. The considered systems are first decomposed into the augmented open-loop transfer functions modified by adding an analytical gain-phase margin tester, then the characteristic equations are formulated, and finally the stability equations are used to find the boundaries of constant gain margins and phase margins. The main advantage of the proposed method is to obtain complete information about the effects of adjustable parameters on gain margins and phase margins; thus it is a useful tool for analysis and design of robust control systems.
GAIN MARGINS AND PHASE MARGINS FOR SAMPLED-DATA CONTROL-SYSTEMS WITH ADJUSTABLE-PARAMETERS
(1991-05-01)
CHANG, CH
;
HAN, KW
;
電控工程研究所
;
Institute of Electrical and Control Engineering
This paper presents a method for finding the boundaries of constant gain margin and phase margin of sampled-data control systems. The considered systems are first modified by adding a gain-phase margin tester, then the characteristic equations are formulated and factored into stability equations, and finally the parameter-plane method is used to find the boundaries of constant gain margin and phase margin. The main advantage of the presented method is to obtain complete information about effects of adjustable and/or variable parameters on gain margins and phase margins.
L(P) NORM BACK-PROPAGATION ALGORITHM FOR ADAPTIVE EQUALIZATION
(1995-09-01)
SIU, S
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CHANG, CH
;
WEI, CH
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
The l(p) norm back propagation algorithm for perceptron based adaptive equalization is analyzed taking account of possible numerical problem encountered when p < 1. Two methods are proposed to overcome the numerical problem. Computer simulations indicate that simultaneous improvement in convergence rate and bit-error-rate (BER) performance can be achieved by using p < 2.
L(P) NORM BACK-PROPAGATION ALGORITHM FOR ADAPTIVE EQUALIZATION
(1995-09-01)
SIU, S
;
CHANG, CH
;
WEI, CH
;
電控工程研究所
;
Institute of Electrical and Control Engineering
The l(p) norm back propagation algorithm for perceptron based adaptive equalization is analyzed taking account of possible numerical problem encountered when p < 1. Two methods are proposed to overcome the numerical problem. Computer simulations indicate that simultaneous improvement in convergence rate and bit-error-rate (BER) performance can be achieved by using p < 2.
MONTE-CARLO SIMULATION FOR CORRELATED VARIABLES WITH MARGINAL DISTRIBUTIONS
(1994-03-01)
CHANG, CH
;
TUNG, YK
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YANG, JC
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土木工程學系
;
Department of Civil Engineering
As computation speed increases, Monte Carlo simulation is becoming a viable tool for engineering design and analysis. However, restrictions are often imposed on multivariate cases in which the involved stochastic parameters are correlated. In multivariate Monte Carlo simulation, a joint probability distribution is required that can only be derived for some limited cases. This paper proposes a practical multivariate Monte Carlo simulation that preserves the marginal distributions of random variables and their correlation structure without requiring the complete joint distribution. For illustration, the procedure is applied to the reliability analysis of a bridge pier against scouring.
OBJECT MOVEMENT IN DISTRIBUTED OBJECT-ORIENTED SYSTEMS
(1994-05-01)
LEE, YS
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WANG, FJ
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CHANG, CH
;
交大名義發表
;
資訊科學與工程研究所
In a distributed object-oriented system-a system containing more than one object-oriented system (OOS)-different OOSs may contain classes with different definitions, different definitions but the same name, or the same definition but different names. Moving an object between two OOSs includes locating a suitable class and creating an instance of the class with the value of the moved object in the destination system. This study discusses what is a suitable class for a moved object in the destination OOS and presents the algorithms for finding such a suitable class. It also discusses the activities of copying the value of the moved object into the instance of a located class in the destination site. A general object movement mechanism and its implementation for a domain specific model are then incorporated into a prototype of a distributed OOS, called DOOSPE.
ON THE CONVERGENCE OF THE L(P)-NORM ALGORITHM FOR POLYNOMIAL PERCEPTRON HAVING DIFFERENT ERROR SIGNAL DISTRIBUTIONS
(1995-03-01)
CHANG, CH
;
SIU, S
;
WEI, CH
;
電控工程研究所
;
Institute of Electrical and Control Engineering
The convergence property of the l(p)-norm algorithm for polynomial-perceptron having different error signal distributions will be analyzed in this paper. To see the effect of error signal on the convergence rate, two types of activation functions are considered in the analysis: one is of a linear type and the other is of a sigmoidal type. Different activation functions yield different ranges of output signal and, in turn, yield different error signal distributions. Linear activation function causes the error signal to be distributed in an uncertain way, while sigmoidal activation function causes it to be distributed in a tightly bounded region. Based on this difference the convergence property of the l(p)-norm algorithm, 1 less than or equal to p less than or equal to 2, is investigated in this paper. Expressions of average learning gains are obtained in terms of the power metric p, the error probability, and the upper bound bf the error signal distribution. Analytic results indicate that it is of particular value in using the l(p)-norm algorithm for the perceptron using sigmoidal activation functions. Computer simulation of an adaptive equalizer using this algorithm confirms the theoretical analysis.
Practical stability issues in CMAC neural network control systems
(1995)
CHEN, FC
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CHANG, CH
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電控工程研究所
;
Institute of Electrical and Control Engineering
PRACTICAL STABILITY ISSUES IN CMAC NEURAL-NETWORK CONTROL-SYSTEMS
(1994)
CHEN, FC
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CHANG, CH
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電控工程研究所
;
Institute of Electrical and Control Engineering
RELIABILITY-BASED PIER SCOUR ENGINEERING - DISCUSSION
(1994-02-01)
CHANG, CH
;
TUNG, YK
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土木工程學系
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Department of Civil Engineering
SENSITIVITY AND UNCERTAINTY ANALYSIS OF A SEDIMENT TRANSPORT MODEL - A GLOBAL APPROACH
(1993-12-01)
CHANG, CH
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YANG, JC
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TUNG, YK
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土木工程學系
;
Department of Civil Engineering
Computerized sediment transport models are frequently employed to quantitatively simulate the movement of sediment materials in rivers. In spite of the deterministic nature of the models, the outputs are subject to uncertainty due to the inherent variability of many input parameters in time and in space, along with the lack of complete understanding of the involved processes. The commonly used first-order method for sensitivity and uncertainty analyses is to approximate a model by linear expansion at a selected point. Conclusions from the first-order method could be of limited use if the model responses drastically vary at different points in parameter space. To obtain the global sensitivity and uncertainty features of a sediment transport model over a larger input parameter space, the Latin hypercubic sampling technique along with regression procedures were employed. For the purpose of illustrating the methodologies, the computer model HEC2-SR was selected in this study. Through an example application, the results about the parameters sensitivity and uncertainty of water surface, bed elevation and sediment discharge were discussed.