• 제목/요약/키워드: Fuzzy Set-Fuzzy Systems

검색결과 667건 처리시간 0.023초

Optimal design of the PID Controller using a predictive control method

  • Kim, Sang-Joo;Lee, Jang-Myung
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • 제5권1호
    • /
    • pp.69-75
    • /
    • 2005
  • This paper is concerned with the design of a predictive PID controller, which has similar features to the model-based predictive controller. A PID type control structure is defined which includes prediction of the outputs and the recalculation of new set points using the future set point data. The optimal values of the PID gains are pre-calculated using the values of gains calculated from an unconstrained generalized predictive control algorithm. Simulation studies demonstrate the performance of the proposed controller and the results are compared with generalized predictive controller and the results are compared with generalized predictive control solutions.

Univector Field Method based Multi-Agent Navigation for Pursuit Problem

  • Viet, Hoang Huu;An, Sang-Hyeok;Chung, Tae-Choong
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • 제12권1호
    • /
    • pp.86-93
    • /
    • 2012
  • This paper presents a new approach to solve the pursuit problem based on a univector field method. In our proposed method, a set of eight agents works together instantaneously to find suitable moving directions and follow the univector field to pursue and capture a prey agent by surrounding it from eight directions in an infinite grid-world. In addition, a set of strategies is proposed to make the pursuit problem more realistic in the real world environment. This is a general approach, and it can be extended for an environment that contains static or moving obstacles. Experimental results show that our proposed algorithm is effective for the pursuit problem.

Cluster-based Information Retrieval with Tolerance Rough Set Model

  • Ho, Tu-Bao;Kawasaki, Saori;Nguyen, Ngoc-Binh
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • 제2권1호
    • /
    • pp.26-32
    • /
    • 2002
  • The objectives of this paper are twofold. First is to introduce a model for representing documents with semantics relatedness using rough sets but with tolerance relations instead of equivalence relations (TRSM). Second is to introduce two document hierarchical and nonhierarchical clustering algorithms based on this model and TRSM cluster-based information retrieval using these two algorithms. The experimental results show that TRSM offers an alterative approach to text clustering and information retrieval.

Intelligent Test Plan Metrics on Adaptive Use Case Approach

  • Kim, R. Young Chul;Lee, Jaehyub
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • 제2권1호
    • /
    • pp.70-77
    • /
    • 2002
  • This paper describes a design driven approach to drive intelligent test plan generation based on adaptive use case (3,5). Its foundation is an object-oriented software design approach which partitions design schema into design architecture of functional components called “design component”. A use case software development methodology of adaptive use case approach developed in I.I .T is employed which preserves this unit architecture on through to the actual code structure. Based on the partition design schema produced during the design phase of this methodology, a test plan is generated which includes a set of component and scenario based test. A software metric is introduced which produces an ordering of this set to enhance productivity and both promote and capitalize on test case reusability, This paper contains an application that illustrates the proposed approach.

The Classification of the Software Quality by the Rough Tolerance Class

  • Choi, Wan-Kyoo;Lee, Sung-Joo
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • 제4권2호
    • /
    • pp.249-253
    • /
    • 2004
  • When we decide the software quality on the basis of the software measurement, the transitive property which is a requirement for an equivalence relation is not always satisfied. Therefore, we propose a scheme for classifying the software quality that employs a tolerance relation instead of an equivalence relation. Given the experimental data set, the proposed scheme generates the tolerant classes for elements in the experiment data set, and generates the tolerant ranges for classifying the software quality by clustering the means of the tolerance classes. Through the experiment, we showed that the proposed scheme could product very useful and valid results. That is, it has no problems that we use as the criteria for classifying the software quality the tolerant ranges generated by the proposed scheme.

Efficient Extraction of Hierarchically Structured Rules Using Rough Sets

  • Lee, Chul-Heui;Seo, Seon-Hak
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • 제4권2호
    • /
    • pp.205-210
    • /
    • 2004
  • This paper deals with rule extraction from data using rough set theory. We construct the rule base in a hierarchical granulation structure by applying core as a classification criteria at each level. When more than one core exist, the coverage is used for the selection of an appropriate one among them to increase the classification rate and accuracy. In Addition, a probabilistic approach is suggested so that the partially useful information included in inconsistent data can be contributed to knowledge reduction in order to decrease the effect of the uncertainty or vagueness of data. As a result, the proposed method yields more proper and efficient rule base in compatability and size. The simulation result shows that it gives a good performance in spite of very simple rules and short conditionals.

이펙트 집합에서 확률측도로서 시그마 모르피즘 개념 (The concept of σ-morphism as a probability measure on the set of effects)

  • 윤용식;강경훈;박진원
    • 한국지능시스템학회논문지
    • /
    • 제19권3호
    • /
    • pp.371-374
    • /
    • 2009
  • 이 논문에서는 사건과 확률변수를 각각 일반화한 이펙트와 옵저버블을 소개하였다. 그리고 $\sigma$-함수의 개념을 소개하고 이펙트 집합위에서의 확률측도로서의 $\sigma$-함수의 성질을 조사하였다.

Biosign Recognition based on the Soft Computing Techniques with application to a Rehab -type Robot

  • Lee, Ju-Jang
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2001년도 ICCAS
    • /
    • pp.29.2-29
    • /
    • 2001
  • For the design of human-centered systems in which a human and machine such as a robot form a human-in system, human-friendly interaction/interface is essential. Human-friendly interaction is possible when the system is capable of recognizing human biosigns such as5 EMG Signal, hand gesture and facial expressions so the some humanintention and/or emotion can be inferred and is used as a proper feedback signal. In the talk, we report our experiences of applying the Soft computing techniques including Fuzzy, ANN, GA and rho rough set theory for efficiently recognizing various biosigns and for effective inference. More specifically, we first observe characteristics of various forms of biosigns and propose a new way of extracting feature set for such signals. Then we show a standardized procedure of getting an inferred intention or emotion from the signals. Finally, we present examples of application for our model of rehabilitation robot named.

  • PDF

퍼지이론을 이용한 색채계획 시스템에 관한 연구 (A Study on the Color Planning System Based on Fuzzy Set Theory)

  • 엄진섭;이준환
    • 한국지능시스템학회논문지
    • /
    • 제7권3호
    • /
    • pp.55-64
    • /
    • 1997
  • 본 논문에서는 퍼지이론을 이용하여 방이나 사무실 등의 색채공간을 사용자가 원하는 분위기로 조화로운 색채공간으로 설계해 가는 의사결정 보조 시스템을 구현하였다. 여기서 사용자가 원하는 분위기란 색채공간이 주는 여러 가지 감정효과를 의미하고 이는 '낭만적인','우아한' 등의 형용사로 표현되며 조화로운 배색이란 원하는 분위기를 유지하면서 전체적인 색채계획이 조화를 이루는 배색을 의미한다. 개발된 색채계획 시스템은 색채공간을 그리기 위한 2차원 그래픽 툴, 사용자가 원하는 분위기를 입력하는 입력부, 사용자의 입력에 따라 주색을 결정하는 주색 결정부, 주색과 조화를 이루는 조화색 결정부, 추천된 색을 수정하는 미세 색조정부 등의 5가지 부시스템으로 구성되어 있다. 이 색채계획 시스템은 인테리어 디자인의 색채계획에 있어서 일반사람들이나 디자이너들에게 도움을 줄 수 있으며, 패션 디자인, 상품 디자인 등의 유사한 색채계획에도 유용하게 활용될 수 있을 거으로 기대된다.

  • PDF

Motion Planning of an Autonomous Mobile Robot in Flexible Manufacturing Systems

  • Kim, Yoo-Seok-;Lee, Jang-Gyu-
    • 한국지능시스템학회:학술대회논문집
    • /
    • 한국퍼지및지능시스템학회 1993년도 Fifth International Fuzzy Systems Association World Congress 93
    • /
    • pp.1254-1257
    • /
    • 1993
  • Presented in this paper is a newly developed motion planning method of an autonomous mobile robot(MAR) which can be applied to flexible manufacturing systems(FMS). The mobile robot is designed for transporting tools and workpieces between a set-up station and machines according to production schedules of the whole FMS. The proposed method is implemented based on an earlier developed real-time obstacle avoidance method which employs Kohonen network for pattern classification of sonar readings and fuzzy logic for local path planning. Particulary, a novel obstacle avoidance method for moving objects using a collision index, collision possibility measure, is described. Our method has been tested on the SNU mobile robot. The experimental results show that the robot successfully navigates to its target while avoiding moving objects.

  • PDF