• Title/Summary/Keyword: fuzzy reasoning

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Weighted Fuzzy Reasoning Using Certainty Factors as Heuristic Information in Weighted Fuzzy Petri Net Representations (가중 퍼지 페트리네트 표현에서 경험정보로 확신도를 이용하는 가중 퍼지추론)

  • Lee, Moo-Eun;Lee, Dong-Eun;Cho, Sang-Yeop
    • Journal of Information Technology Applications and Management
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    • v.12 no.4
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    • pp.1-12
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    • 2005
  • In general, other conventional researches propose the fuzzy Petri net-based fuzzy reasoning algorithms based on the exhaustive search algorithms. If it can allow the certainty factors representing in the fuzzy production rules to use as the heuristic information, then it can allow the reasoning of rule-based systems to perform fuzzy reasoning in more effective manner. This paper presents a fuzzy Petri net(FPN) model to represent the fuzzy production rules of a rule-based system. Based on the fuzzy Petri net model, a weighted fuzzy reasoning algorithm is proposed to Perform the fuzzy reasoning automatically, This algorithm is more effective and more intelligent reasoning than other reasoning methods because it can perform fuzzy reasoning using the certainty factors which are provided by domain experts as heuristic information

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Interval-Valued Fuzzy Set Backward Reasoning Using Fuzzy Petri Nets (퍼지 페트리네트를 이용한 구간값 퍼지 집합 후진추론)

  • 조상엽;김기석
    • Journal of Korea Multimedia Society
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    • v.7 no.4
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    • pp.559-566
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    • 2004
  • In general, the certainty factors of the fuzzy production rules and the certainty factors of fuzzy propositions appearing in the rules are represented by real values between zero and one. If it can allow the certainty factors of the fuzzy production rules and the certainty factors of fuzzy propositions to be represented by interval -valued fuzzy sets, then it can allow the reasoning of rule-based systems to perform fuzzy reasoning in more flexible manner. This paper presents fuzzy Petri nets and proposes an interval-valued fuzzy backward reasoning algorithm for rule-based systems based on fuzzy Petri nets Fuzzy Petri nets model the fuzzy production rules in the knowledge base of a rule-based system, where the certainty factors of the fuzzy propositions appearing in the fuzzy production rules and the certainty factors of the rules are represented by interval-valued fuzzy sets. The algorithm we proposed generates the backward reasoning path from the goal node to the initial nodes and then evaluates the certainty factor of the goal node. The proposed interval-valued fuzzy backward reasoning algorithm can allow the rule-based systems to perform fuzzy backward reasoning in a more flexible and human-like manner.

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Multistage Fuzzy Production Systems Modeling and Approximate Reasoning Based on Fuzzy Petri Nets (다단계 퍼지추론 시스템의 퍼지 페트리네트 모델링과 근사추론)

  • 전명근
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.12
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    • pp.84-94
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    • 1996
  • In this work, a fuzzy petri net model for modeling a general form of fuzzy production system which consists of chaining fuzzy production rules and so requires multistage reasoning process is presented. For the obtained fuzzy petri net model, the net will be transformed into some matrices, and also be systematically led to an algebraic form of a state equation. Since it is fond that the approximate reasoning process in fuzzy systems corresponds to the dynamic behavior of the fuzzy petri net, it is further shown that the multistage reasoning process can be carried out by executing the state equation.

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Fuzzy Pr/T Net Representation of Interval-valued Fuzzy Set Reasoning (구간값 퍼지집합 추론의 퍼지 Pr/T 네트 표현)

  • Cho, Sang-Yeop
    • The KIPS Transactions:PartB
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    • v.9B no.6
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    • pp.783-790
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    • 2002
  • This paper proposes a fuzzy Pr/T net representation of interval-valued fuzzy set reasoning, where fuzzy production rules are used for knowledge representation, and the belief of fuzzy production rules are represented by interval-valued fuzzy sets. The presented interval-valued fuzzy reasoning algorithm is much closer to human intuition and reasoning than other methods because this algorithm uses the proper belief evaluation functions according to fuzzy concepts in fuzzy production rules.

Weighted Fuzzy Backward Reasoning Using Weighted Fuzzy Petri-Nets (가중 퍼지 페트리네트를 이용한 가중 퍼지 후진추론)

  • Cho Sang Yeop;Lee Dong En
    • Journal of Internet Computing and Services
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    • v.5 no.4
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    • pp.115-124
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    • 2004
  • This paper presents a weighted fuzzy backward reasoning algorithm for rule-based systems based on weighted fuzzy Petri nets. The fuzzy production rules in the knowledge base of a rule-based system are modeled by weighted fuzzy Petri nets, where the truth values of the propositions appearing in the fuzzy production rules and the certainty factors of the rules are represented by fuzzy numbers. Furthermore, the weights of the propositions appearing in the rules are also represented by fuzzy numbers. The proposed weighted fuzzy backward reasoning generates the backward reasoning path from the goal node to the initial nodes and then evaluates the certainty factor of the goal node. The algorithm we proposed can allow the rule-based systems to perform weighted fuzzy backward reasoning in more flexible and human-like manner.

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Optimazation of Fuzzy Systems by Switching Reasoning Methods Dynamically

  • Smith, Michael H.;Takagi, Hideyuki
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1993.06a
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    • pp.1354-1357
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    • 1993
  • This paper proposes that the best reasoning(i.e. rule evaluation) method which should be used in a fuzzy system significantly depends on the reasoning environment. It is shown that allowing for dynamic switching of reasoning methods leads to better performance, even when only two different reasoning methods are considered. This paper discusses DSFS (Dynamic Switching Fuzzy System) which dynamically switches and finds the best reasoning method (from among 80 different possible reasoning methods) to use depending on the reasoning situation. To overcome the reasoning speed and memory problem of DSFS due to its computational requirements, the DSFS Switching Reasoning Table method is proposed and its higher performance as compared to a conventional fuzzy system is shown. Finally, efforts to obtain general relationships between the characteristics of different reasoning methods and the actual control surface/environment is discussed.

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Interval-valued Fuzzy Set Reasoning Using Fuzzy Petri Nets (퍼지 페트리네트를 이용한 구간간 퍼지집합 추론)

  • 조경달;조상엽
    • Journal of KIISE:Software and Applications
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    • v.31 no.5
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    • pp.625-631
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    • 2004
  • In general, the certainty factors of the fuzzy production rules and the certainty factors of fuzzy Propositions appearing in the rules are represented by real values between zero and one. If it can allow the certainty factors of the fuzzy production rules and the certainty factors of fuzzy propositions to be represented by interval-valued fuzzy sets, then it can allow the reasoning of rule-based systems to perform fuzzy reasoning in more flexible manner(15). This paper presents a fuzzy Petri nets and proposes an interval-valued fuzzy reasoning algorithm for rule-based systems based on fuzzy Petri nets. Fuzzy Petri nets model the fuzzy production rules in the knowledge base of a rule-based system, where the certainty factors of the fuzzy Propositions appearing in the furry production rules and the certainty factors of the rules are represented by interval-valued fuzzy sets. The proposed interval-valued fuzzy set reasoning algorithm can allow the rule-based systems to perform fuzzy reasoning in a more flexible manner.

Modelling Method of Road Choice using Fuzzy Reasoning (퍼지추론을 이용한 도로경로선택 모델화 수법)

  • 남궁문;성수련;김경태;서승환
    • Journal of the Korean Institute of Intelligent Systems
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    • v.5 no.3
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    • pp.92-100
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    • 1995
  • Fuzzy reasoning has been applied to analysis of traffic problems on urban arterial road. As the analysis on factors of route choice has been already carried out, its result can be used for construction of the model. Route choice rate estimation by fuzzy reasoning was discussed from its structure and accuracy. The major objective of the study is to introduce some kinds of methods with fuzzy reasoning and to make their feature obvious. First, the production system model is introduced with consideration of reality to actual travel behavior. Second, overlapping areas of fuzzy language function are investigated. Finally, process of fuzzy reasoning was also considered. Five kinds of Fuzzy reasoning are compared to investigate in relation between shapes of membership function and estimation validity.

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INTERPOLATIVE REASONING FOE COMPUTATIONALLY EFFICIENT OPTIMAL FUZZY CONTROL

  • Kacprzyk, Janusz
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1993.06a
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    • pp.1270-1273
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    • 1993
  • Fuzzy optimal control is considered. An optimal sequence of controls is sought best satisfying fuzzy constraints on the controls and fuzzy goals on the states (outputs), with a fuzzy system under control Control over a fixed and specified, implicitly specified, fuzzy, and infinite termination time is discussed. For computational efficiency a small number of reference fuzzy staters and controls is to be assumed by which fuzzy controls and stated are approximated. Optimal control policies reference fuzzy states are determined as a fuzzy relation used, via the compositional rule of inference, to derive an optimal control. Since this requires a large number of overlapping reference fuzzy controls and states implying a low computational efficiency, a small number of nonoverlapping reference fuzzy states and controls is assumed, and then interpolative reasoning is used to infer an optimal fuzzy control for a current fuzzy state.

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