• Title/Summary/Keyword: fuzzy modeling

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자동변속기의 본드선도 모델링 및 제어 (Bond Graph Modeling and Control for an Automatic Transmission)

  • 강민수;강조웅;김종식
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 추계학술대회 논문집
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    • pp.425-430
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    • 2002
  • An automatic transmission model using the bond graph techniques is developed for analyzing shift characteristics of vehicles. Bond graph models can be systemically manipulated to yield state space equations of standard form. Bond graph techniques are applied for modeling overall automatic transmission systems and shift models. A fuzzy controller is synthesized for the verification of a shifting model in the ${1^st} gear to the {2^nd}$ gear. Simulation results show the fitness of models by the bond graph techniques.

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분산 기반의 Gradient Based Fuzzy c-means 에 의한 MPEG VBR 비디오 데이터의 모델링과 분류 (Modeling and Classification of MPEG VBR Video Data using Gradient-based Fuzzy c_means with Divergence Measure)

  • 박동철;김봉주
    • 한국통신학회논문지
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    • 제29권7C호
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    • pp.931-936
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    • 2004
  • GPDF(Gaussian Probability Density Function)을 효율적으로 군집화할 수 있는 GBFCM(DM)(Gradient Based Fuzzy c_means with Divergence Measure) 알고리즘이 본 논문에서 제안되었다. 제안된 GBFCM(DM)은 데이터 사이의 거리 척도로 발산거리(Divergence measure)를 적용한 새로운 형태의 FCM으로, 기존의 GBFCM에 기반을 두는 알고리즘이다. 본 논문에서는 MPEG VBR 비디오 데이터를 GPDF형태의 다차원 데이터로 변형시켜 모델링 하고, 모델링 한 MPEG VBR 비디오 데이터를 영화 또는 스포츠 형태로 분류하는데 응용되었다. 본 논문의 실험에서 기존의 FCM, GBFCM과 새롭게 제안된 GBFCM(DM)을 사용하여 모델링 및 분류결과를 상호 비교하였다. 비교결과 GBFCM(DM)이 오분류율의 기준에서 기존의 다른 알고리즘들에 비해 약 5∼l5%의 향상된 성능을 보였다.

DNA 코딩 기법을 이용한 웨이브렛 기반 퍼지 모델링 (Wavelet-Based Fuzzy Modeling Using a DNA Coding Method)

  • 주영훈;이영우;유진영
    • 한국지능시스템학회논문지
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    • 제13권6호
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    • pp.737-742
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    • 2003
  • 본 논문에서는 DNA 코딩 방법을 이용하여 새로운 웨이블렛 기반 퍼지 모델링 방법을 제안한다. DNA 코딩 방법은 기존의 유전 알고리즘에 비해 지식 표현에 있어서 더 다양하고, 최적화 수행에 있어서 더 좋다고 알려져 있다 그 이유는 DNA 코딩 방법은 생물학적 DNA에 기반하여 더 풍부한 유전 정보를 암호화할 수 있기 때문이다. 제안한 방법은 웨이블렛 변환 기법을 사용함으로써 퍼지 모델을 생성한다. 여기서, 계수들은 DNA 코딩 방법을 이용하여 동정된다. 즉, 웨이블렛 변환과 DNA 코딩 방법의 장점들을 사용함으로써 더 좋은 퍼지 모델을 생성한다. 제안된 방법의 우수성을 증명하기 위해서 기존지 유전알고리즘과 그 결과를 비교한다.

The Application of Fuzzy Logic to Assess the Performance of Participants and Components of Building Information Modeling

  • Wang, Bohan;Yang, Jin;Tan, Adrian;Tan, Fabian Hadipriono;Parke, Michael
    • Journal of Construction Engineering and Project Management
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    • 제8권4호
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    • pp.1-24
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    • 2018
  • In the last decade, the use of Building Information Modeling (BIM) as a new technology has been applied with traditional Computer-aided design implementations in an increasing number of architecture, engineering, and construction projects and applications. Its employment alongside construction management, can be a valuable tool in helping move these activities and projects forward in a more efficient and time-effective manner. The traditional stakeholders, i.e., Owner, A/E and the Contractor are involved in this BIM system that is used in almost every activity of construction projects, such as design, cost estimate and scheduling. This article extracts major features of the application of BIM from perspective of participating BIM components, along with the different phrases, and applies to them a logistic analysis using a fuzzy performance tree, quantifying these phrases to judge the effectiveness of the BIM techniques employed. That is to say, these fuzzy performance trees with fuzzy logic concepts can properly translate the linguistic rating into numeric expressions, and are thus employed in evaluating the influence of BIM applications as a mathematical process. The rotational fuzzy models are used to represent the membership functions of the performance values and their corresponding weights. Illustrations of the use of this fuzzy BIM performance tree are presented in the study for the uninitiated users. The results of these processes are an evaluation of BIM project performance as highly positive. The quantification of the performance ratings for the individual factors is a significant contributor to this assessment, capable of parsing vernacular language into numerical data for a more accurate and precise use in performance analysis. It is hoped that fuzzy performance trees and fuzzy set analysis can be used as a tool for the quality and risk analysis for other construction techniques in the future. Baldwin's rotational models are used to represent the membership functions of the fuzzy sets. Three scenarios are presented using fuzzy MEAN, AND and OR gates from the lowest to intermediate levels of the tree, and fuzzy SUM gate to relate the intermediate level to the top component of the tree, i.e., BIM application final performance. The use of fuzzy MEAN for lower levels and fuzzy SUM gates to reach the top level suggests the most realistic and accurate results. The methodology (fuzzy performance tree) described in this paper is appropriate to implement in today's construction industry when limited objective data is presented and it is heavily relied on experts' subjective judgment.

Automatic Generation of Fuzzy Rules using the Fuzzy-Neural Networks

  • Ahn, Taechon;Oh, Sungkwun;Woo, Kwangbang
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1993년도 Fifth International Fuzzy Systems Association World Congress 93
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    • pp.1181-1186
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    • 1993
  • In the paper, a new design method of rule-based fuzzy modeling is proposed for model identification of nonlinear systems. The structure indentification is carried out, utilizing fuzzy c-means clustering. Fuzzy-neural networks composed back-propagation algorithm and linear fuzzy inference method, are used to identify parameters of the premise and consequence parts. To obtain optimal linguistic fuzzy implication rules, the learning rates and momentum coefficients are tuned automatically using a modified complex method.

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Job Scheduling Problem Using Fuzzy Numbers and Fuzzy Delphi Method

  • Park, Seung-Hun;Chang, In-Seong
    • 대한산업공학회지
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    • 제22권4호
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    • pp.607-617
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    • 1996
  • This paper shows that fuzzy set theory can be useful in modeling and solving job scheduling problems with uncertain processing times. The processing times are considered as fuzzy numbers(fuzzy intervals or time intervals) and the fuzzy Delphi method is used to estimate a reliable time interval of each processing time. Based on these time estimates, we then propose an efficient methodology for calculating the optimal sequence and the fuzzy makespan.

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쓰레기 소각 플랜트 연소 제어를 위한 다변수 퍼지 모델링 (Multi-variable Fuzzy Modeling for Combustion Control of Refuse Incineration Plant)

  • 박종진;최규석;안인석
    • 한국인터넷방송통신학회논문지
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    • 제9권5호
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    • pp.191-197
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    • 2009
  • 본 논문에서는 쓰레기 소각로의 효율적인 연소 제어를 위해 쓰레기 소각 플랜트의 다변수 퍼지 모델을 구한다. 먼저 복잡하고 비선형 시스템인 소각로의 모델을 구하기 위해 다변수 퍼지 모델링을 수행한다. 얻어진 다변수 퍼지 모델은 주어지는 입력에 대해 소각로의 출력을 정확하게 예측한다. 그리고 얻어진 퍼지 모델은 시뮬레이터 구현에 사용되어 소각로의 출력예측에 의한 제어전략의 구축 및 운전자의 훈련 등에 사용되는 운전보조 시뮬레이션 시스템을 구현할 수 있다.

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Modeling of Bank Asset Management System based on Intelligent Agent

  • Kim, Dae-Su;Kim, Chang-Suk
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제1권1호
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    • pp.81-86
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    • 2001
  • In this paper, we investigated the modeling of Bank Asset Management System(BAME) based on intelligent agent. To achieve this goal, we introduced several kinds of agents that show intelligent features. BAMS is a user friendly system and adopts fuzzy converting system and fuzzy matching system that returns reasonable similarity matching results. Generation function of the proximity degree is suggested. Fuzzification of investment type categories and feature values are defined, and generation of proximity degree is also derived. An example of bank asset management system is introduced and simulated. Investment type matching utilizing fuzzy measure is tested and it showed quite reasonable similarity matching results.

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Hybrid Multi-layer Perceptron with Fuzzy Set-based PNs with the Aid of Symbolic Coding Genetic Algorithms

  • Roh, Seok-Beom;Oh, Sung-Kwun;Ahn, Tae-Chon
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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    • pp.155-157
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    • 2005
  • We propose a new category of hybrid multi-layer neural networks with hetero nodes such as Fuzzy Set based Polynomial Neurons (FSPNs) and Polynomial Neurons (PNs). These networks are based on a genetically optimized multi-layer perceptron. We develop a comprehensive design methodology involving mechanisms of genetic optimization and genetic algorithms, in particular. The augmented genetically optimized HFPNN (namely gHFPNN) results in a structurally optimized structure and comes with a higher level of flexibility in comparison to the one we encounter in the conventional HFPNN. The GA-based design procedure being applied at each layer of HFPNN leads to the selection of preferred nodes (FPNs or PNs) available within the HFPNN. In the sequel, two general optimization mechanisms are explored. First, the structural optimization is realized via GAs whereas the ensuing detailed parametric optimization is carried out in the setting of a standard least square method-based learning. The performance of the gHFPNNs quantified through experimentation where we use a number of modeling benchmarks-synthetic and experimental data already experimented with in fuzzy or neurofuzzy modeling.

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웨이브렛 변환과 유전 알고리듬을 이용한 퍼지 모델링 (Fuzzy Modeling Using Wavelet Transform and Genetic Algorithm)

  • 이승준;주영훈;박진배
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 D
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    • pp.2327-2329
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    • 2000
  • This paper addresses the use of a nonlinear modeling procedure which construct a wavelet-based fuzzy model using genetic algorithm. A fuzzy inference system has the functional equivalence with a wavelet transform. Therefore, a wavelet-based fuzzy model using GA inherits the advantage of wavelet transform. Hereby, its performance is promoted. By help of the ability of GA to search the optimum globally, parameters of wavelet transform is determined closely to the optimal point. The feasibility of the proposed fuzzy model is proved by modelling a highly nonlinear function and comparing it with previous research.

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