• Title/Summary/Keyword: fuzzy 추론

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Fast Fuzzy Inference Algorithm for Fuzzy System constructed with Triangular Membership Functions (삼각형 소속함수로 구성된 퍼지시스템의 고속 퍼지추론 알고리즘)

  • Yoo, Byung-Kook
    • Journal of the Korean Institute of Intelligent Systems
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    • v.12 no.1
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    • pp.7-13
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    • 2002
  • Almost applications using fuzzy theory are based on the fuzzy inference. However fuzzy inference needs much time in calculation process for the fuzzy system with many input variables or many fuzzy labels defined on each variable. Inference time is dependent on the number of arithmetic Product in computation Process. Especially, the inference time is a primary constraint to fuzzy control applications using microprocessor or PC-based controller. In this paper, a simple fast fuzzy inference algorithm(FFIA), without loss of information, was proposed to reduce the inference time based on the fuzzy system with triangular membership functions in antecedent part of fuzzy rule. The proposed algorithm was induced by using partition of input state space and simple geometrical analysis. By using this scheme, we can take the same effect of the fuzzy rule reduction.

MIMO Fuzzy Reasoning Method using Learning Ability (학습기능을 사용한 MIMO 퍼지추론 방식)

  • Park, Jin-Hyun;Lee, Tae-Hwan;Choi, Young-Kiu
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2008.10a
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    • pp.175-178
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    • 2008
  • Z. Cao had proposed NFRM(new fuzzy reasoning method) which infers in detail using relation matrix. In spite of the small inference rules, it shows good performance than mamdani's fuzzy inference method. But the most of fuzzy systems are difficult to make fuzzy inference rules in the case of MIMO system. The past days, We had proposed the MIMO fuzzy inference which had extended a Z. Cao's fuzzy inference to handle MIMO system. But many times and effort needed to determine the relation matrix elements of MIMO fuzzy inference by heuristic and trial and error method in order to improve inference performances. In this paper, we propose a MIMO fuzzy inference method with the learning ability witch is used a gradient descent method in order to improve the performances. Through the computer simulation studies for the inverse kinematics problem of 2-axis robot, we show that proposed inference method using a gradient descent method has good performances.

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Fuzzy Reasonings based on Fuzzy Petei Net Representations (퍼지페트리네트 표현을 기반으로 하는 퍼지추론)

  • 조상엽
    • Korean Journal of Cognitive Science
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    • v.10 no.4
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    • pp.51-62
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    • 1999
  • This paper proposes a fuzzy Petri net representation to represent the fuzzy production rules of a rule-based expert system. Based on the fuzzy Petri net representation. we present a fuzzy reasoning algorithms which consist of forward and b backward reasoning algorithm. The proposed algorithms. which use the proper belief evaluation functions according to fuzzy concepts in antecedent and consequent of a fuzzy production rule. are more closer to human intuition and reasoning than other methods. The forward reasoning algorithm can be represented by a reachability tree as a kind of finite directed tree. The backward reasoning algorithm generates the backward reasoning path from the goal to the initial nodes and then evaluates the belief value of the goal node using belief evaluation functions.

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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.

A study of MIMO Fuzzy system with a Learning Ability (학습기능을 갖는 MIMO 퍼지시스템에 관한 연구)

  • Park, Jin-Hyun;Bae, Kang-Yul;Choi, Young-Kiu
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.3
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    • pp.505-513
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    • 2009
  • Z. Cao had proposed NFRM(new fuzzy reasoning method) which infers in detail using relation matrix. In spite of the small inference rules, it shows good performance than mamdani's fuzzy inference method. But the most of fuzzy systems are difficult to make fuzzy inference rules in the case of MIMO system. The past days, We had proposed the MIMO fuzzy inference which had extended a Z. Cao's fuzzy inference to handle MIMO system. But many times and effort needed to determine the relation matrix elements of MIMO fuzzy inference by heuristic and trial and error method in order to improve inference performances. In this paper, we propose a MIMO fuzzy inference method with the learning ability witch is used a gradient descent method in order to improve the performances. Through the computer simulation studies for the inverse kinematics problem of 2-axis robot, we show that proposed inference method using a gradient descent method has good performances.

A Study of Fuzzy Reasoning in Expert System (전문가 대체 시스템에서의 퍼지 추론에 관한 연구)

  • 김성혁
    • Journal of the Korean Society for information Management
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    • v.7 no.1
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    • pp.68-78
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    • 1990
  • This paper shows the fuzzy reasoning process that is specifically designed to deal wit the inexactness or fuzziness in the expert systems. The impact of overall fuzzy reasoning reviewed when knowledge with certainty is provided. Also, the example of fuzzy reazoning used at probabilistic inference is presented.

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Fuzzy Inference Network and Search Strategy using Neural Logic Network (신경논리망을 이용한 퍼지추론 네트워크와 탐색전략)

  • 이말례
    • Journal of Korea Multimedia Society
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    • v.4 no.2
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    • pp.189-196
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    • 2001
  • Fuzzy logic ignores some information in the reasoning process. Neural networks are powerful tools for the pattern processing, but, not appropriate for the logical reasoning. To model human knowledge, besides pattern processing capability, the logical reasoning capability is equally important. Another new neural network called neural logic network is able to do the logical reasoning. Because the fuzzy inference is a fuzzy logical reasoning, we construct fuzzy inference network based on the neural logic network, extending the existing rule - inference network. and the traditional propagation rule is modified.

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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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Nonlinear Inference Using Fuzzy Cluster (퍼지 클러스터를 이용한 비선형 추론)

  • Park, Keon-Jung;Lee, Dong-Yoon
    • Journal of Digital Convergence
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    • v.14 no.1
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    • pp.203-209
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    • 2016
  • In this paper, we introduce a fuzzy inference systems for nonlinear inference using fuzzy cluster. Typically, the generation of fuzzy rules for nonlinear inference causes the problem that the number of fuzzy rules increases exponentially if the input vectors increase. To handle this problem, the fuzzy rules of fuzzy model are designed by dividing the input vector space in the scatter form using fuzzy clustering algorithm which expresses fuzzy cluster. From this method, complex nonlinear process can be modeled. The premise part of the fuzzy rules is determined by means of FCM clustering algorithm with fuzzy clusters. The consequence part of the fuzzy rules have four kinds of polynomial functions and the coefficient parameters of each rule are estimated by using the standard least-squares method. And we use the data widely used in nonlinear process for the performance and the nonlinear characteristics of the nonlinear process. Experimental results show that the non-linear inference is possible.

Modular Fuzzy Inference Systems for Nonlinear System Control (비선형 시스템 제어를 위한 모듈화 피지추론 시스템)

  • 권오신
    • Journal of the Korean Institute of Intelligent Systems
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    • v.11 no.5
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    • pp.395-399
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    • 2001
  • This paper describes modular fuzzy inference systems(MFIS) with adaptive capability to extract fuzzy inference modules from observation data through the learning process. The proposed MFIS is based on the structural similarity to Tagaki-Sugeno fuzzy models and a modular neural architecture. The learning of MFIS is done by assigning new fuzzy inference modules and by updating the parameters of existing modules. The fuzzy inference modules consist of local model network and fuzzy gating network. The parameters of the MFIS are updated by the standard LMS algorithm. The performance of the MFIS is illustrated with adaptive control of a nonlinear dynamic system.

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