• Title/Summary/Keyword: Hard C-Means Clustering

Search Result 42, Processing Time 0.025 seconds

Nonlinear Process Modeling Using Hard Partition-based Inference System (Hard 분산 분할 기반 추론 시스템을 이용한 비선형 공정 모델링)

  • Park, Keon-Jun;Kim, Yong-Kab
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
    • /
    • v.7 no.4
    • /
    • pp.151-158
    • /
    • 2014
  • In this paper, we introduce an inference system using hard scatter partition method and model the nonlinear process. To do this, we use the hard scatter partition method that partition the input space in the scatter form with the value of the membership degree of 0 or 1. The proposed method is implemented by C-Means clustering algorithm. and is used for the initial center values by means of binary split. by applying the LBG algorithm to compensate for shortcomings in the sensitive initial center value. Hard-scatter-partitioned input space forms the rules in the rule-based system modeling. The premise parameters of the rules are determined by membership matrix by means of C-Means clustering algorithm. The consequence part of the rules is expressed in the form of polynomial functions and the coefficient parameters of each rule are determined by the standard least-squares method. The data widely used in nonlinear process is used to model the nonlinear process and evaluate the characteristics of nonlinear process.

Partially Evaluated Genetic Algorithm based on Fuzzy Clustering (퍼지 클러스터링 기반의 국소평가 유전자 알고리즘)

  • Yoo Si-Ho;Cho Sung-Bae
    • Journal of KIISE:Software and Applications
    • /
    • v.31 no.9
    • /
    • pp.1246-1257
    • /
    • 2004
  • To find an optimal solution with genetic algorithm, it is desirable to maintain the population sire as large as possible. In some cases, however, the cost to evaluate each individual is relatively high and it is difficult to maintain large population. To solve this problem we propose a novel genetic algorithm based on fuzzy clustering, which considerably reduces evaluation number without any significant loss of its performance by evaluating only one representative for each cluster. The fitness values of other individuals are estimated from the representative fitness values indirectly. We have used fuzzy c-means algorithm and distributed the fitness using membership matrix, since it is hard to distribute precise fitness values by hard clustering method to individuals which belong to multiple groups. Nine benchmark functions have been investigated and the results are compared to six hard clustering algorithms with Euclidean distance and Pearson correlation coefficients as fitness distribution method.

Optimal Identification of IG-based Fuzzy Model by Means of Genetic Algorithms (유전자 알고리즘에 의한 IG기반 퍼지 모델의 최적 동정)

  • Park, Keon-Jun;Lee, Dong-Yoon;Oh, Sung-Kwun
    • Proceedings of the KIEE Conference
    • /
    • 2005.05a
    • /
    • pp.9-11
    • /
    • 2005
  • We propose a optimal identification of information granulation(IG)-based fuzzy model to carry out the model identification of complex and nonlinear systems. To optimally identity we use genetic algorithm (GAs) sand Hard C-Means (HCM) clustering. An initial structure of fuzzy model is identified by determining the number of input, the selected input variables, the number of membership function, and the conclusion inference type by means of GAs. Granulation of information data with the aid of Hard C-Means(HCM) clustering algorithm help determine the initial parameters of fuzzy model such as the initial apexes of the membership functions and the initial values of polynomial functions being used in the premise and consequence part of the fuzzy rules. And the initial parameters are tuned effectively with the aid of the genetic algorithms(GAs) and the least square method. Numerical example is included to evaluate the performance of the proposed model.

  • PDF

Genetically Optimized Information Granules-based FIS (유전자적 최적 정보 입자 기반 퍼지 추론 시스템)

  • Park, Keon-Jun;Oh, Sung-Kwun;Lee, Young-Il
    • Proceedings of the KIEE Conference
    • /
    • 2005.10b
    • /
    • pp.146-148
    • /
    • 2005
  • In this paper, we propose a genetically optimized identification of information granulation(IG)-based fuzzy model. To optimally design the IG-based fuzzy model we exploit a hybrid identification through genetic alrogithms(GAs) and Hard C-Means (HCM) clustering. An initial structure of fuzzy model is identified by determining the number of input, the seleced input variables, the number of membership function, and the conclusion inference type by means of GAs. Granulation of information data with the aid of Hard C-Means(HCM) clustering algorithm help determine the initial paramters of fuzzy model such as the initial apexes of the membership functions and the initial values of polyminial functions being used in the premise and consequence part of the fuzzy rules. And the inital parameters are tuned effectively with the aid of the genetic algorithms and the least square method. And also, we exploite consecutive identification of fuzzy model in case of identification of structure and parameters. Numerical example is included to evaluate the performance of the proposed model.

  • PDF

Design of Hard Partition-based Non-Fuzzy Neural Networks

  • Park, Keon-Jun;Kwon, Jae-Hyun;Kim, Yong-Kab
    • International journal of advanced smart convergence
    • /
    • v.1 no.2
    • /
    • pp.30-33
    • /
    • 2012
  • This paper propose a new design of fuzzy neural networks based on hard partition to generate the rules of the networks. For this we use hard c-means (HCM) clustering algorithm. The premise part of the rules of the proposed networks is realized with the aid of the hard partition of input space generated by HCM clustering algorithm. The consequence part of the rule is represented by polynomial functions. And the coefficients of the polynomial functions are learned by BP algorithm. The number of the hard partition of input space equals the number of clusters and the individual partitioned spaces indicate the rules of the networks. Due to these characteristics, we may alleviate the problem of the curse of dimensionality. The proposed networks are evaluated with the use of numerical experimentation.

Information Granulation-based Fuzzy Inference Systems by Means of Genetic Optimization and Polynomial Fuzzy Inference Method

  • Park Keon-Jun;Lee Young-Il;Oh Sung-Kwun
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • v.5 no.3
    • /
    • pp.253-258
    • /
    • 2005
  • In this study, we introduce a new category of fuzzy inference systems based on information granulation to carry out the model identification of complex and nonlinear systems. Informal speaking, information granules are viewed as linked collections of objects (data, in particular) drawn together by the criteria of proximity, similarity, or functionality. To identify the structure of fuzzy rules we use genetic algorithms (GAs). Granulation of information with the aid of Hard C-Means (HCM) clustering algorithm help determine the initial parameters of fuzzy model such as the initial apexes of the membership functions and the initial values of polynomial functions being used in the premise and consequence part of the fuzzy rules. And the initial parameters are tuned effectively with the aid of the genetic algorithms and the least square method (LSM). The proposed model is contrasted with the performance of the conventional fuzzy models in the literature.

Selection of Optimal Sensor Locations for Thermal Error Model of Machine tools (공작기계 열오차 모델의 최적 센서위치 선정)

  • 안중용
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
    • /
    • 1999.10a
    • /
    • pp.345-350
    • /
    • 1999
  • The effectiveness of software error compensation for thermally induced machine tool errors relies on the prediction accuracy of the pre-established thermal error models. The selection of optimal sensor locations is the most important in establishing these empirical models. In this paper, a methodology for the selection of optimal sensor locations is proposed to establish a robust linear model which is not subjected to collinearity. Correlation coefficient and time delay are used as thermal parameters for optimal sensor location. Firstly, thermal deformation and temperatures are measured with machine tools being excited by sinusoidal heat input. And then, after correlation coefficient and time delays are calculated from the measured data, the optimal sensor location is selected through hard c-means clustering and sequential selection method. The validity of the proposed methodology is verified through the estimation of thermal expansion along Z-axis by spindle rotation.

  • PDF

Design of improved Mulit-FNN for Nonlinear Process modeling

  • Park, Hosung;Sungkwun Oh
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2002.10a
    • /
    • pp.102.2-102
    • /
    • 2002
  • In this paper, the improved Multi-FNN (Fuzzy-Neural Networks) model is identified and optimized using HCM (Hard C-Means) clustering method and optimization algorithms. The proposed Multi-FNN is based on FNN and use simplified and linear inference as fuzzy inference method and error back propagation algorithm as learning rules. We use a HCM clustering and genetic algorithms (GAs) to identify both the structure and the parameters of a Multi-FNN model. Here, HCM clustering method, which is carried out for the process data preprocessing of system modeling, is utilized to determine the structure of Multi-FNN according to the divisions of input-output space using I/O process data. Also, the parame...

  • PDF

The Design of Fuzzy Controller by Means of Genetic Optimization and Estimation Algorithms

  • Oh, Sung-Kwun;Rho, Seok-Beom
    • KIEE International Transaction on Systems and Control
    • /
    • v.12D no.1
    • /
    • pp.17-26
    • /
    • 2002
  • In this paper, a new design methodology of the fuzzy controller is presented. The performance of the fuzzy controller is sensitive to the variety of scaling factors. The design procedure is based on evolutionary computing (more specifically, a genetic algorithm) and estimation algorithm to adjust and estimate scaling factors respectively. The tuning of the soiling factors of the fuzzy controller is essential to the entire optimization process. And then we estimate scaling factors of the fuzzy controller by means of two types of estimation algorithms such as HCM (Hard C-Means) and Neuro-Fuzzy model[7]. The validity and effectiveness of the proposed estimation algorithm for the fuzzy controller are demonstrated by the inverted pendulum system.

  • PDF

Analysis of Saccharomyces Cell Cycle Expression Data using Bayesian Validation of Fuzzy Clustering (퍼지 클러스터링의 베이지안 검증 방법을 이용한 발아효모 세포주기 발현 데이타의 분석)

  • Yoo Si-Ho;Won Hong-Hee;Cho Sung-Bae
    • Journal of KIISE:Software and Applications
    • /
    • v.31 no.12
    • /
    • pp.1591-1601
    • /
    • 2004
  • Clustering, a technique for the analysis of the genes, organizes the patterns into groups by the similarity of the dataset and has been used for identifying the functions of the genes in the cluster or analyzing the functions of unknown gones. Since the genes usually belong to multiple functional families, fuzzy clustering methods are more appropriate than the conventional hard clustering methods which assign a sample to a group. In this paper, a Bayesian validation method is proposed to evaluate the fuzzy partitions effectively. Bayesian validation method is a probability-based approach, selecting a fuzzy partition with the largest posterior probability given the dataset. At first, the proposed Bayesian validation method is compared to the 4 representative conventional fuzzy cluster validity measures in 4 well-known datasets where foray c-means algorithm is used. Then, we have analyzed the results of Saccharomyces cell cycle expression data evaluated by the proposed method.