• 제목/요약/키워드: Fuzzy approximate reasoning

검색결과 46건 처리시간 0.025초

An Exponential Representation Form for Fuzzy Logic

  • Shen, Zuliang;Ding, Liya
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1993년도 Fifth International Fuzzy Systems Association World Congress 93
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    • pp.1281-1284
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    • 1993
  • By the exponential representation form (EF) for fuzzy logic, any fuzzy value a (in fuzzy valued logic or fuzzy linguistic valued logic) can be represented as Bc, where B is called the truth base and C the confidence exponent. This paper will propose the basic concepts of this form and discuss its interesting properties. By using a different truth base, the exponential form can be used to represent the positive and the negative logic in fuzzy valued logic as well as in fuzzy linguistic valued logic. Some Simple application examples of EF for approximate reasoning are also illustrated in this paper.

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퍼지 전문가 시스템을 이용한 강관 하이드로포밍의 성형성 예측에 관한 연구 (Optimization of tube hydroforming process by using fuzzy expert system)

  • 박광수;김동규;이동활;문영훈
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2004년도 춘계학술대회 논문집
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    • pp.194-197
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    • 2004
  • In the tube hydroforming process, a tube is placed into the die cavity and the ends of the tube are sealed by fixing the axial cylinder piston into the ends. Then the tube is pressurized with a hydraulic fluid and simultaneously the axial cylinders move to feed the material into the expansion zone. Therefore, the quantitative relationship between process parameters such as internal pressure and feeding amount and hydroformabillity, is hard to establish because of their high complexity and many unknown factors. In this study, the empirical and the quantitative relationship between process parameters and hydroformabillity are analyzed by fuzzy rules. Fuzzy expert system is an advanced expert system which uses fuzzy rule and approximate reasoning. Many process parameters are converted to the quantitative relationship by use of approximate reasoning of fuzzy expert system. The comparison between experimentally measured hydroformabillity from hydroforming experiments and the predicted values by fuzzy expert system shows a good agreement.

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A Hybrid Approach Using Case-based Reasoning and Fuzzy Logic for Corporate Bond Rating

  • Kim, Hyun-jung;Shin, Kyung-shik
    • 한국지능정보시스템학회:학술대회논문집
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    • 한국지능정보시스템학회 2003년도 춘계학술대회
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    • pp.474-483
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    • 2003
  • A number of studies for corporate bond rating classification problems have demonstrated that artificial intelligence approaches such as Case-based reasoning (CBR) can be alternative methodologies to statistical techniques. CBR is a problem solving technique in that the case specific knowledge of past experience is utilized to find a most similar solution to the new problems. To build a successful CBR system to deal with human information processing, the representation of knowledge of each attribute is an important key factor We propose a hybrid approach of using fuzzy sets that describe the approximate phenomena of the real world because it handles inexact knowledge represented by common linguistic terms in a similar way as human reasoning compared to the other existing techniques. Integration of fuzzy sets with CBR is important to develop effective methods for dealing with vague and incomplete knowledge to statistical represent using membership value of fuzzy sets in CBR.

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건설공사의 위험도 분석평가 및 모델개발 (Development of a Risk Analysis Assessment Models for the Construction Projects)

  • 이정식
    • 한국구조물진단유지관리공학회 논문집
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    • 제3권2호
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    • pp.233-240
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    • 1999
  • Even though the recent construction safety disasters not only result in the loss inside construction sites but also become to a large public disasters, safety activities are managed in an irrational way and safety rules are ignored in the construction sites which leads to occur same type of disasters repeatedly. In this paper, a fuzzy set theoretic approach to risk analysis is proposed as an alternative to the techniques currently used in the general construction projects safety. Then the concept of risk evaluation using linguistic representation of the likelihood, exposure and consequences is introduced. A risk assessment model using approximate reasoning technique base on fuzzy logic is presented to drive fuzzy values of risk and numerical example for risk analysis is also presented to illustrate the results.

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퍼지생성규칙을 위한 퍼지페트리네트표현에서 후진추론 (Backward Reasoning in Fuzzy Petri - net Representation for Fuzzy Production Rules)

  • 조상엽
    • 한국정보처리학회논문지
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    • 제5권4호
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    • pp.951-958
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    • 1998
  • 본 논문에서는 퍼지생성규칙을 표현한 퍼지페트리네트에서 사용할 수 있는 후진추론 알고리즘을 제안한다. 퍼지페트리 네트워크표현은 근사추론 시스템을 모형화하거나 퍼지추론엔진을 구현하는데 사용할 수 있다. 본 논문이 제안한 알고리즘은 단순히 min과 max 게산만을 하는 기존의 알고리즘과는 달리 퍼지생성규칙의 전제부와 결론부에 퍼지개념의 유무에 따라 적절한 믿음값평가함수을 사용하여 보다 더 인간적인 추론을 한다. 후진추론 알고리즘은 목표노드에서 시작노드까지의 후진추론 통로를 구한 후에 믿음값평가함수를 이용하여 목표노드의 믿음값을 구한다.

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구간 결정값을 갖는 의사결정시스템의 양방향 퍼지 추론망 (A bidirectional fuzy inference network for interval valued decision making systems)

  • 전명근
    • 전자공학회논문지C
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    • 제34C권10호
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    • pp.98-105
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    • 1997
  • In this work, we proesent a bidirectional approximate reasoning method and fuzzy inference network for interval valued decision making systems. For this, we propose a new type of similarity measure between two fuzzy vectors based on the Ordered Weighted Averaging (OWA) operator. Since the proposed similarity measure has a structure to give the extreme values by choosing a suitable weighting vector of the OWA operator, it can render an interval valued similarity value. From this property, we derive a bidirectional approximate reasoning method based on the similarity measure and show its fuzzy inference network implementation for the decision making systems requiring the interval valued decisions.

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Fuzzy Neural Controller with Additive Hybrid Operators

  • Hayashi, Yoichi;Keller, James M.;Chen, Zhihong
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1993년도 Fifth International Fuzzy Systems Association World Congress 93
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    • pp.1118-1120
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    • 1993
  • Fuzzy logic places a considerable burden on an inference engine for applications such as control or approximate reasoning. Various neural network architectures have been proposed to deal with the computational task, and yet, maintain flexibility in the desired traits of the final system. Recently, we introduced a trainable network architecture whose nodes implement weighted Yager additive hybrid operators for fuzzy logic inference in an approximate reasoning setting. In this paper we examine the utility of such networks for control situations. We show that they are capable of learning control functions which are piece-wise monotonic in each of the variables. The learning ability is demonstrated through an example.

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FUZZY HYPERCUBES: A New Inference Machines

  • Kang, Hoon
    • 한국지능시스템학회논문지
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    • 제2권2호
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    • pp.34-41
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    • 1992
  • A robust and reliable learning and reasoning mechanism is addressed based upon fuzzy set theory and fuzzy associative memories. The mechanism stores a priori an initial knowledge base via approximate learning and utilizes this information for decision-making systems via fuzzy inferencing. We called this fuzzy computer architecture a 'fuzzy hypercube' processing all the rules in one clock period in parallel. Fuzzy hypercubes can be applied to control of a class of complex and highly nonlinear systems which suffer from vagueness uncertainty. Moreover, evidential aspects of a fuzzy hypercube are treated to assess the degree of certainty or reliability together with parameter sensitivity.

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Psychological Jump in Vague Knowledge

  • Nakatsuyama, Mikio
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1998년도 The Third Asian Fuzzy Systems Symposium
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    • pp.343-346
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    • 1998
  • This paper deals with the decision in vague knowledge, One method is a classic theory. That is to say, constraints and goals in the vague knowledge. Another method is the fuzzy catastrophe. If there exist two fuzzy variables, there may be a discontinuity which plays an important role in decision.

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