• Title/Summary/Keyword: Fuzzy Functions

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Intuitionistic Fuzzy δ-continuous Functions

  • Eom, Yeon Seok;Lee, Seok Jong
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.13 no.4
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    • pp.336-344
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    • 2013
  • In this paper, we characterize the intuitionistic fuzzy ${\delta}$-continuous, intuitionistic fuzzy weakly ${\delta}$-continuous, intuitionistic fuzzy almost continuous, and intuitionistic fuzzy almost strongly ${\theta}$-continuous functions in terms of intuitionistic fuzzy ${\delta}$-closure and interior or ${\theta}$-closure and interior.

Fuzzy Linearity of the Seminormed Fuzzy Integrals of Interval-valued Functions (구간 값을 갖는 함수의 준 노름 적분의 선형성)

  • Kim, Mi-Hye;Kim, Mi-Suk;Lee, Seok Jong
    • Journal of the Korean Institute of Intelligent Systems
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    • v.14 no.3
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    • pp.262-266
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    • 2004
  • In general, the fuzzy integral lacks some important properties that Lebesgue integral possesses. One of them is linearity. In this paper, we introduce fuzzy linearity in which we use the supremum and the infimum instead of additon and scalar multiplication in the expression of linearity and show that the fuzzy linearity of the seminormed fuzzy integrals of interval-valued functions when the fuzzy measure g is fuzzy additive, the continuous t-seminorm is saturated and measurable functions satisfy the condition[Max].

Backward Control Simulation of Tractor-Trailer Using Fuzzy Logic and Genetic Algorithms (퍼지논리와 유전알고리즘을 이용한 트랙터-트레일러의 후진제어 시뮬레이션)

  • 조성인;기노훈
    • Journal of Biosystems Engineering
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    • v.20 no.1
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    • pp.87-94
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    • 1995
  • When farmer loads and unloads farm products with a trailer, linked to a tractor, the tractor-trailer is backed up to the loading duck. However, travelling backward is not easy and takes a time for even skilled operators. Therefore, unmanned backing up is necessary to save the effort. A backward controller of tractor-trailer was simulated using fuzzy logic and genetic algorithms. Operators drive the tractor-trailer back and forth several times for backing up to the loading duck. As the operators did it, a backward controller was designed using fuzzy logic. And genetic algorithms was applied to improve the performance of the backward controller. With the strings coded with the fuzzy membership functions, genetic operations were carried out. After 30 generations, the best fitted fuzzy membership functions were found. Those membership functions were used in the fuzzy backward controller. The fuzzy controller combined with genetic algorithms showed the better results than the fuzzy controller did alone.

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Fuzzy Rules and Membership Functions Tunning of Fuzzy Controller Applying Genetic Algorithms of Speed Control of DC Motor (퍼지 제어기의 퍼지규칙 및 멤버쉽 함수 튜닝에 유전알고리즘을 적용한 직류 모터의 속도제어)

  • Hwang, G.H.;Kim, H.S.;Park, J.H.;Hwang, C.S.;Kim, J.K.
    • Proceedings of the KIEE Conference
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    • 1996.07b
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    • pp.1021-1023
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    • 1996
  • This paper proposes a design of self-tuning fuzzy rules and membership functions based on genetic algorithms. Sub-optimal fuzzy rules and membership functions are found by using genetic algorithms. Genetic algorithms are used for tuning fuzzy rules and membership functions. A arbitrary speed trajectories are selected for the reference input of the proposed methods. Experimental results show the good performance in the DC motor control system with the self-tuning fuzzy controller based on genetic algorithms.

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On some properties of vague bi-groups and fuzzy bi-functions (애매 bi-군과 퍼지 bi-함수의 성질에 관한 연구)

  • Jang, Lee-Chae;Kim, Tae-Kyun;Lee, Byung-Je;Kim, Won-Joo
    • Journal of the Korean Institute of Intelligent Systems
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    • v.20 no.3
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    • pp.356-361
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    • 2010
  • M. Demirci[Vague groups, J. math. Anal. Appl. vol.230, pp. 142-156, 1999] studied the vague group operation on a crisp set as a fuzzy function and estabished the vague group structure on a crisp set. In this paper we consider bi-groups which are studied by A.A.A. Agboola and L.S. Akinola. And we also will define vague bi-groups and fuzzy bi-functions and we investigate some basic operations on the vague bi-group and fuzzy bi-functions.

Minimum Fuzzy Membership Function Extraction for Automatic Premature Ventricular Contraction Detection (자동 조기심실수축 탐지를 위한 최소 퍼지소속함수의 추출)

  • Lim, Joon-Shik
    • Journal of Internet Computing and Services
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    • v.8 no.1
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    • pp.125-132
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    • 2007
  • This paper presents an approach to detect premature ventricular contractions(PVC) using the neural network with weighted fuzzy membership functions(NEWFM), NEWFM classifies normal and PVC beats by the trained weighted fuzzy membership functions using wavelet transformed coefficients extracted from the MIT-BIH PVC database. The eight most important coefficients of d3 and d4 are selected by the non-overlap area distribution measurement method. The selected 8 coefficients are used for 3 data sets showing reliable accuracy rates 99,80%, 99,21%, and 98.78%, respectively, which means the selected input features are less dependent to the data sets. The ECG signal segments and fuzzy membership functions of the 8 coefficients enable input features to interpret explicitly.

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Extracting Wisconsin Breast Cancer Prediction Fuzzy Rules Using Neural Network with Weighted Fuzzy Membership Functions (가중 퍼지 소속함수 기반 신경망을 이용한 Wisconsin Breast Cancer 예측 퍼지규칙의 추출)

  • Lim Joon Shik
    • The KIPS Transactions:PartB
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    • v.11B no.6
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    • pp.717-722
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    • 2004
  • This paper presents fuzzy rules to predict diagnosis of Wisconsin breast cancer using neural network with weighted fuzzy membership functions (NNWFM). NNWFM is capable of self-adapting weighted membership functions to enhance accuracy in prediction from the given clinical training data. n set of small, medium, and large weighted triangular membership functions in a hyperbox are used for representing n set of featured input. The membership functions are randomly distributed and weighted initially, and then their positions and weights are adjusted during learning. After learning, prediction rules are extracted directly from the enhanced bounded sums of n set of weighted fuzzy membership functions. Two number of prediction rules extracted from NNWFM outperforms to the current published results in number of rules and accuracy with 99.41%.

Multiobjective Nonlinear Decision Making with Fuzzy Parameters and Fuzzy Equal Goals (퍼지모수들과 퍼지항등목표들을 가지는 다목적 비선형 의사결정)

  • 윤연근;남현우;이상완
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.20 no.41
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    • pp.41-50
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    • 1997
  • In this paper, we presents the method for finding the compensatory solution for fuzzy multiobjective nonlinear programming problem with fuzzy parameters involved in the problem-formulation process and fuzzy equal goals of the decision maker for each of the objective functions. The fuzzy parameters in the objective functions and the constraints characterized by fuzzy numbers. The proposed method can be applied to case with multiobjective problems and guarantee an efficient solution. An illustrative numerical example is presented.

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TIETZE EXTENSION THEOREM FOR ORDERED FUZZY PRE-EXTREMALLY DISCONNECTED SPACES

  • Uma, M.K.;Roja, E.;Balasubramanian, G.
    • East Asian mathematical journal
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    • v.24 no.3
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    • pp.213-221
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    • 2008
  • In this paper, a new class of fuzzy topological spaces called ordered fuzzy pre-extremally disconnected spaces is introduced. Tietze extension theorem for ordered fuzzy pre-extremally disconnected spaces has been discussed as in [9] besides proving several other propositions and lemmas.

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Fuzzy Model of Semiconductor Devices (반도체 소자의 퍼지모델)

  • 강근택;권태하
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.26 no.12
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    • pp.2001-2009
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    • 1989
  • This study suggests the use of fuzzy model in the semiconductor devices modeling as a black box approach. When membership functions of fuzzy sets used in a fuzzy model are simple piecewise-linear functions, the fuzzy model can be reresented in a simple equation. To show that the fuzzy model can be very realistic and simple when used in semiconductor devices modeling, we construct fuzzy models for bipolar transistor, MOSFET and GaAs FET, and compare those with canonical piecewise-linear models.

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