• Title/Summary/Keyword: Fuzzy Knowledge Processing

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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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Development of Automated Analysis System for Model Plane Engine Using Fuzzy Knowledge Processing

  • Lee, Joon-Seong;Lee, Shin-Pyo
    • 한국지능시스템학회논문지
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    • 제12권2호
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    • pp.171-176
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    • 2002
  • This paper describes a new automated analysis system for model plane engine. An automatic finite element (FE) mesh generation technique, which is based on the fuzzy knowledge processing and computational geometry technique, is incorporated into the system, together with one of commercial FE analysis codes, ANSYS, and one of commercial solid modelers, Designbase, The system allows a geometry model of concern to be automatically converted to different FE models, depending on physical phenomena of plane engine to be analyzed, i.e. deformation analysis, thermal analysis and so on. The FE models are then automatically analyzed by the FE analysis code. Among a whole process of analysis, the definition of a geometry model, the designation of local node patterns, the assignment of material properties and boundary conditions onto the geometry model are only the interactive processes to be done by a user. The interactive operations can be processed in a few minutes. The other processes which are time consuming and labour-intensive in conventional CAE systems are fully automatically performed in a personal computer environment. The proposed analysis system is successfully applied to evaluate a model plane entwine.

FUZZY LOGIC KNOWLEDGE SYSTEMS AND ARTIFICIAL NEURAL NETWORKS IN MEDICINE AND BIOLOGY

  • Sanchez, Elie
    • 한국지능시스템학회논문지
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    • 제1권1호
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    • pp.9-25
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    • 1991
  • This tutorial paper has been written for biologists, physicians or beginners in fuzzy sets theory and applications. This field is introduced in the framework of medical diagnosis problems. The paper describes and illustrates with practical examples, a general methodology of special interest in the processing of borderline cases, that allows a graded assignment of diagnoses to patients. A pattern of medical knowledge consists of a tableau with linguistic entries or of fuzzy propositions. Relationships between symptoms and diagnoses are interpreted as labels of fuzzy sets. It is shown how possibility measures (soft matching) can be used and combined to derive diagnoses after measurements on collected data. The concepts and methods are illustrated in a biomedical application on inflammatory protein variations. In the case of poor diagnostic classifications, it is introduced appropriate ponderations, acting on the characterizations of proteins, in order to decrease their relative influence. As a consequence, when pattern matching is achieved, the final ranking of inflammatory syndromes assigned to a given patient might change to better fit the actual classification. Defuzzification of results (i.e. diagnostic groups assigned to patients) is performed as a non fuzzy sets partition issued from a "separating power", and not as the center of gravity method commonly employed in fuzzy control. It is then introduced a model of fuzzy connectionist expert system, in which an artificial neural network is designed to build the knowledge base of an expert system, from training examples (this model can also be used for specifications of rules in fuzzy logic control). Two types of weights are associated with the connections: primary linguistic weights, interpreted as labels of fuzzy sets, and secondary numerical weights. Cell activation is computed through MIN-MAX fuzzy equations of the weights. Learning consists in finding the (numerical) weights and the network topology. This feed forward network is described and illustrated in the same biomedical domain as in the first part.

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피지이론과 버블기법을 이용한 3차원 구조물의 유한요소해석을 위한 요소생성기법 (Mesh Generation Methodology for FE Analysis of 3D Structures Using Fuzzy Knowledge and Bubble Method)

  • 이준성;이은철
    • 한국지능시스템학회논문지
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    • 제19권2호
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    • pp.230-235
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    • 2009
  • 본 논문은 3차원구조물의 유한요소해석을 위한 자동 유한요소 생성에 관한 것으로 퍼지이론과 버블요소 생성기법, 상용 솔리드모델러로 구성되어진다. 새로운 요소생성과정은 (a) 해석모델인 형상모델링 정의, (b) 버블생성, 그리고 (c) 요소생성으로 이루어진다. 형상모델링에는 상용 솔리드모델러를 이용하였으며 버블은 각 지점에서의 버블간격함수에 의해 생성되어진다. 버블간격 함수는 지식처리수법에 의해 조절되어 진다. 요소생성을 위해서는 기본적으로 데로우니방법을 도입하였다. 이러한 3차원 구조물에 대한 유한요소의 자동생성은 해석을 위해 큰 잇점이 있다. 실제적인 현 시스템의 효용성을 검증하기위해 3차원 형상에 대한 예를 제시하였다.

A Construction of Fuzzy Inference Network based on Neural Logic Network and its Search Strategy

  • Lee, Mal-rey
    • 한국산업정보학회:학술대회논문집
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    • 한국산업정보학회 2000년도 추계공동학술대회논문집
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    • pp.375-389
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    • 2000
  • 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. For the search strategies to find out the belief value of a conclusion in the fuzzy inference network, we conduct a simulation to evaluate the search costs for searching sequentially and searching by means of search priorities.

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퍼지추론에 의한 PID제어기의 파라미터 Tuning의 구성 (Self -Tuning Scheme for Parameters of PID Controllers by Fuzzy Inference)

  • 이요섭;홍순일
    • 융합신호처리학회논문지
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    • 제4권4호
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    • pp.52-57
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    • 2003
  • PID제어기의 파라미터의 조정 방법이 전문가의 경험적 지식과 플랜트 스텝응답 파형 모양에 기초하여 퍼지 싱글톤 추론에 의해 행하는 방법을 나타내었다. 파라미터 조정방법은 두 레벨이 있다. 높은 레벨은 모델링 할 수 없는 플랜트 특성에 대하여 전문가의 Know-how에 기초하여 제어기의 수정계수를 결정하는 것이다. 저 단계는 Ziegler-Nichol 의 한계 감도법의 응답 특성에 의해 특정 계수를 결정한다. 마지막 단계는 량과 제어응답 파형의 면적법에서 얻은 특정량에서 조정 규칙으로 취하고 퍼지추론에 수정 계수와 특정계수로 조정규칙을 만들어 퍼지 싱글톤 추론에 의해 PID제어기의 각 파라미터를 적정한 값으로 자동조정 하는 법을 나타내었다.

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Mobile User Interface Pattern Clustering Using Improved Semi-Supervised Kernel Fuzzy Clustering Method

  • Jia, Wei;Hua, Qingyi;Zhang, Minjun;Chen, Rui;Ji, Xiang;Wang, Bo
    • Journal of Information Processing Systems
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    • 제15권4호
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    • pp.986-1016
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    • 2019
  • Mobile user interface pattern (MUIP) is a kind of structured representation of interaction design knowledge. Several studies have suggested that MUIPs are a proven solution for recurring mobile interface design problems. To facilitate MUIP selection, an effective clustering method is required to discover hidden knowledge of pattern data set. In this paper, we employ the semi-supervised kernel fuzzy c-means clustering (SSKFCM) method to cluster MUIP data. In order to improve the performance of clustering, clustering parameters are optimized by utilizing the global optimization capability of particle swarm optimization (PSO) algorithm. Since the PSO algorithm is easily trapped in local optima, a novel PSO algorithm is presented in this paper. It combines an improved intuitionistic fuzzy entropy measure and a new population search strategy to enhance the population search capability and accelerate the convergence speed. Experimental results show the effectiveness and superiority of the proposed clustering method.

Fuzzy Petri-net Approach to Fault Diagnosis in Power Systems Using the Time Sequence Information of Protection System

  • Roh, Myong-Gyun;Hong, Sang-Eun
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.1727-1731
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    • 2003
  • In this paper we proposed backward fuzzy Petri-net to diagnoses faults in power systems by using the time sequence information of protection system. As the complexity of power systems increases, especially in the case of multiple faults or incorrect operation of protective devices, fault diagnosis requires new and systematic methods to the reasoning process, which improves both its accuracy and its efficiency. The fuzzy Petri-net models of protection system are composed of the operating process of protective devices and the fault diagnosis process. Fault diagnosis model, which makes use of the nature of fuzzy Petri-net, is developed to overcome the drawbacks of methods that depend on operator knowledge. The proposed method can reduce processing time and increase accuracy when compared with the traditional methods. And also this method covers online processing of real-time data from SCADA (Supervisory Control and Data Acquisition)

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

  • 이말례
    • 한국멀티미디어학회논문지
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    • 제4권2호
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    • pp.189-196
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    • 2001
  • 퍼지 논리의 추론과정에서 일부의 정보가 무시되어 적절하지 못한 추론 결과를 초래 할 수 있다. 한편 신경망은 패턴 처리에는 적합하지만 인간의 지식을 모델링하기 위해서 필요한 논리적인 추론에는 부적합하다. 그러나 신경망의 변형인 신경 논리망을 이용하면 논리적인 추론이 가능하다. 따라서 본 논문에서는 기존의 신경 논리망을 기반으로 하는 추론네트워크를 확장하여 퍼지 추론 네트워크를 구성한다. 그리고 기존의 추론 네트워크에서 사용되는 전파규칙을 보완하여 적용한다. 퍼지 추론 네트워크상에서 퍼지 규칙의 실행부에 해당하는 명제의 믿음 값을 결정하기 위해서는 추론하고자 하는 명제에 연결된 노드들을 탐색해야 한다.

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

  • 조상엽
    • 정보처리학회논문지B
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    • 제9B권6호
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    • pp.783-790
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    • 2002
  • 본 논문에서는 구간값 퍼지집합 추론의 퍼지 Pr/T 네트 표현을 제안한다. 여기에서 퍼지생성규칙은 지식표현을 위해 사용하고, 퍼지생성규칙의 믿음값은 구간값 퍼지집합으로 표현한다. 제안한 구간값 퍼지집합 추론 알고리즘은 퍼지생성규칙의 전제부와 결론부에 있는 퍼지개념에 따라서 적절한 믿음값평가함수를 사용하기 때문에 다른 방법보다 사람이 사용하는 직관과 추론에 더 가깝다.