Browsing by Author "Sun, CT"

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A neural network model of hysteresis
(1996)
Wei, JD
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Sun, CT
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交大名義發表
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資訊工程學系
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National Chiao Tung University
Hysteresis is an effect of memory, which is frequently observed in the realm of nature. The purpose of this paper is trying to understand more of it, such that we may achieve better performance from the systems which are hysteresis-embedded. A hypothesis-based neural network model is offered in this paper. We name it the Synchronous Delay Network (SDN) model. It can be realized as a feed-forward neural network. We also discuss the possible applications in this paper.
A novel small-world model: Using social mirror identities for epidemic simulations
(2005-10-01)
Huang, CY
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Sun, CT
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Hsieh, JL
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Chen, YMA
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Lin, HL
The authors propose a small-world network model that combines cellular automata with the social mirror identities of daily-contact networks for purposes of performing epidemiological simulations. The social mirror identity concept was established to integrate human long-distance movement and daily visits to fixed locations. After showing that the model is capable of displaying such small-world effects as low degree of separation and relatively high degree of clustering on a societal level, the authors offer proof of its ability to display R-o properties-considered central to all epidemiological studies. To test their model, they simulated the 2003 severe acute respiratory syndrome (SARS) outbreak.
Comments on "A computational evolutionary approach to evolving game strategies and cooperation"
(2004-06-01)
Wu, HC
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Sun, CT
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資訊工程學系
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Department of Computer Science
Azuaje offers an approach to the co-evolution of competing virtual creatures and a model for the evolution of game strategies and their emerging behaviors [1]. This model can be greatly simplified and optimal solutions can be obtained more quickly and easily by using an analytical approach. We emphasize the importance of performing a model analysis before choosing an evolutionary or analytical approach to a problem. Furthermore, Azuaje's model is derived from the Prisoner's Dilemma, a classical model in game theory; some results have already been discussed in the literature. We discuss his model from the perspective of game theorists.
Comments on "Constraining the optimization of a fuzzy logic controller"
(2001-08-01)
Wu, MD
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Sun, CT
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資訊工程學系
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Department of Computer Science
Genetic algorithms (GAs) are a highly effective and efficient means of solving optimization problems. Gene encoding, fitness landscape and genetic operations are vital to successfully developing a GA. Cheong and Lai(1) described a novel method, which employed an enhanced genetic algorithm with multiple populations, to optimize a fuzzy controller, and the experimental results revealed that their method was effective in producing a well-formed fuzzy rule-base. However, their encoding method and fitness function appear unnatural and inefficient. This study proposes an alternative method of concise genetic encoding and fitness design.
Constructing a cooperative distance learning system: The CORAL experience
(1996)
Chou, C
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Sun, CT
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傳播研究所
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資訊工程學系
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Institute of Communication Studies
This article focuses on the Cooperative Remotely Accessible Learning (CORAL) system to promote cooperative constructive distance learning currently under development at National Chiao Tung University in Taiwan. The CORAL system is a collective and collaborative project intended to integrate four major components in concept and construction: an interactive learning environment, educational foundations and implications, domain knowledge, and research efforts. The CORAL system provides the first comprehensive and networked courseware written in Chinese, The development process of CORAL including analysis, design, development, and evaluation is reported. Research issues are also addressed.
Constructing hysteretic memory in neural networks
(2000-08-01)
Wei, JD
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Sun, CT
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資訊工程學系
;
Department of Computer Science
Hysteresis is a unique type of dynamic, which contains an important property, rate-independent memory. In addition to other memory-related studies such as time delay neural networks, recurrent networks, and reinforcement learning, rate-independent memory deserves further attention owing to its potential applications. In this work, we attempt to define hysteretic memory (rate-independent memory) and examine whether or not it could be modeled in neural networks. Our analysis results demonstrate that other memory-related mechanisms are not hysteresis systems. A novel neural cell, referred to herein as the propulsive neural unit, is then proposed. The proposed cell is based on a notion related the submemory pool, which accumulates the stimulus and ultimately assists neural networks to achieve model hysteresis. In addition to training by backpropagation, a combination of such cells can simulate given hysteresis trajectories.
Designing a networked-sharing construction environment
(2002-09-01)
Lin, S
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Sun, CT
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Kao, G
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教育研究所
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Institute of Education
Energy, matter, and entropy in evolutionary computation
(1996)
Yang, SMA
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Sun, CT
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Hsu, CH
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資訊工程學系
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Department of Computer Science
Experiencing CORAL: Design and implementation of distant cooperative learning
(1996-08-01)
Sun, CT
;
Chou, C
;
傳播研究所
;
資訊工程學系
;
Institute of Communication Studies
This paper describes application of information technologies to education, outlines the educational foundations and design strategies of the applications, and addresses related research issues, In this paper, we introduce the CORAL (COoperative Remotely Accessible Learning) system, currently under development at National Chiao Tung University in Taiwan, as an example of how information technologies are being used in science and engineering education.
Experiencing CORAL: Design and implementation of distant cooperative learning
(1996-08-01)
Sun, CT
;
Chou, C
;
傳播研究所
;
資訊工程學系
;
Institute of Communication Studies
This paper describes application of information technologies to education, outlines the educational foundations and design strategies of the applications, and addresses related research issues, In this paper, we introduce the CORAL (COoperative Remotely Accessible Learning) system, currently under development at National Chiao Tung University in Taiwan, as an example of how information technologies are being used in science and engineering education.
Fuzzy modeling employing fuzzy polyploidy genetic algorithms
(2002-03-01)
Wu, MD
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Sun, CT
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資訊工程學系
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Department of Computer Science
Fuzzy modeling generally comprises structure identification and parameter identification. The former determines the structure of a rule-base, whereas the latter determines the contents of each rule. Applying neural networks or genetic algorithms to identify the parameter sets and structures of a fuzzy system is increasingly popular owing to their ability to learn and adapt. However, most conventional approaches cannot integrate structure identification and parameter identification efficiently. This work presents a general approach to fuzzy modeling, i.e. fuzzy polyploidy genetic algorithms which integrate structure identification and parameter identification in a single evolution process. Capable of simulating the structural adaptation process of natural evolution, the proposed model is a generalized model for simultaneously optimizing both structure and parameters of fuzzy rule-bases. The structural adaptation proposed herein provides complete structural operations to simulate structural variation process and simple to complex life form of natural evolution. Illustrative examples involving typical FLCs, such as Mamdani and TSK models, demonstrate the effectiveness of applying the polyploidy scheme.
Influence of local information on social simulations in small-world network models
(2005-10-01)
Huang, CY
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Sun, CT
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Lin, HC
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資訊工程學系
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Department of Computer Science
As part of Watts and Strogatz's small-world model of complex networks, local information mechanisms such as landscape properties are used to approximate real-world conditions in social simulations. The authors investigated the influence of local information on social simulations based on the small-world network model, using a cellular automata variation with added shortcuts as a test platform for simulating the spread of an epidemic disease or cultural values/ideas. Results from experimental simulations show that the percentage of weak individuals should be considered significant local information, but vertex degree influences and the distribution patterns of weak individuals should not. When exploring contagion problems, the results encourage a future emphasis on setting and the proportions of specific values of local information related to infection strength or resistance, and a reduced emphasis on the detailed topological structure of small-world network models and the distribution patterns of specific values of local information.
Influence of local information on social simulations under the small-world model
(2004)
Lin, HC
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Huang, CY
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Sun, CT
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資訊工程學系
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Department of Computer Science
Watts and Strogatzs "small world model" of disordered networks is becoming an increasingly popular research tool for modeling human society. As part of this approach, local information mechanisms (landscape properties) are used to approximate real-world conditions in social simulations. The authors investigate the influence of local information on social simulations that are performed using the small world model. In addition to defining local information, we use a cellular automata variation with added shortcuts as a test platform for simulating the spread of an epidemic and examining various influences. We believe our results will help future researchers determine appropriate simulation parameters.
Large simulation of hysteresis systems using a piecewise polynomial function
(2002-07-01)
Wei, JD
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Sun, CT
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資訊工程學系
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Department of Computer Science
Hysteresis is a memory effect frequently observed in physical research. The output of a hysteresis system is independent of input speed. This property, known as rate independence, significantly distinguishes hysteresis from short-term memory effects. This work conducts a numerical simulation to demonstrate that conventional models with short-term memories cannot properly simulate hysteresis trajectories. Subsequently, a novel model is developed to contribute to the field of system modeling. Experimental results confirm that the proposed model can model hysteresis behavior precisely.
Network tournament pedagogical approach involving game playing in artificial intelligence
(2003-07-01)
Wu, MD
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Liao, YH
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Sun, CT
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資訊工程學系
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Department of Computer Science
Game playing and genetic algorithms (GAs) are two important topics in artificial intelligence (AI). In this work we employ network tournament to assist in teaching these concepts associated with AI. Three exercises that implement a game-playing program are designed to help students learn relevant topics in AI. The first exercise involves game theory, e.g. mini-max search and alpha-beta pruning. The second exercise helps students understand the critical nature of a good heuristic function in game playing. And, the third exercise introduces GAs to learn a heuristic function. In addition to these exercises, this work also designs several programming toolkits to help students complete their exercises, such as a network tournament interface, a graphical man-machine interface, and a genetic algorithm based game-playing engine. These exercises encompass pertinent topics involving artificial intelligence and the network tournament. The network tournament provides a relatively easy means of Othello competition, and has merit in improving students' motivation for learning relevant topics.
Parameter adaptation within co-adaptive learning classifier systems
(2004)
Huang, CY
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Sun, CT
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資訊工程學系
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Department of Computer Science
The authors propose a co-adaptive approach to controlling parameters for coevolution-based learning classifier systems. By taking advantage of the on-line incremental learning capability of such systems, solutions can be produced that completely cover a target problem. The system combines the advantages of both adaptive and self-adaptive parameter-control approaches. Using a coevolution model means that two learning classifier systems can operate in parallel to simultaneously solve target and parametersetting problems. Furthermore, the approach needs very little time to become efficient in terms of latent learning, since it only requires small amounts of information on performance metrics during early run-time stages. Our experimental results show that the proposed system outperforms comparable models regardless of a problem's stationary/non-stationary status.
Self-adaptive genetic algorithm learning in game playing
(1995)
Sun, CT
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Wu, MD
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資訊工程學系
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Department of Computer Science
Special issue on e-learning - Foreword
(2005-09-01)
Lewis, R
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Chan, TW
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Chou, C
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Sun, CT
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資訊工程學系
Special section on bioinformatics - Foreword
(2003-11-01)
Hwang, JK
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Kao, MY
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Sun, CT
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Hsu, WL
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生物科技學系
Strain rate effect on in-plane shear strength of unidirectional polymeric composites
(2005-10-01)
Tsai, JL
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Sun, CT
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機械工程學系
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Department of Mechanical Engineering
The strain rate effect on the in-plane shear strength of unidirectional composites was investigated. Off-axis S2/8552 glass epoxy block specimens were employed to produce in-plane shear failure. In order to determine the strain rate effect, specimens were tested in compression at various strain rates. For strain rates less than 1/s, experiments were conducted on an MTS machine. For higher strain rates, they were performed using a Hopkinson pressure bar. Experimental observations indicated that, for composite specimens with off-axis angles less than 10 degrees, fiber microbuckling is the dominant failure mechanism. However, for the specimens with off-axis angles between 15 degrees and 45 degrees, in-plane sharing is the major failure mode. If the off-axis angle is greater than 45 degrees, out of plane shear failure would take place. Only the in-plane shear failure mechanism was concerned in this study. The shear strain rate was obtained from the uniaxial strain rate by relating the effective plastic strain rate to the plastic shear strain rate with the aid of a viscoplasticity model. Through coordinate transformation law, the uniaxial failure stresses were then converted to a plot of shear stress versus transverse normal stress from which the shear strength in the absence of transverse normal stress (sigma(22) = 0) was obtained. Experimental results showed that the shear strength of the composite is quite sensitive to strain rate and the shear strength increases as strain rate increases. In contrast, the shear failure strain decreases as strain rate increases. (c) 2005 Elsevier Ltd. All rights reserved.