• Title/Summary/Keyword: fuzzy C-means clustering

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MRI Data Segmentation Using Fuzzy C-Mean Algorithm with Intuition (직관적 퍼지 C-평균 모델을 이용한 자기 공명 영상 분할)

  • Kim, Tae-Hyun;Park, Dong-Chul;Jeong, Tai-Kyeong;Lee, Yun-Sik;Min, Soo-Young
    • Journal of IKEEE
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    • v.15 no.3
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    • pp.191-197
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    • 2011
  • An image segmentation model using fuzzy c-means with intuition (FCM-I) model is proposed for the segmentation of magnetic resonance image in this paper. In FCM-I, a measurement called intuition level is adopted so that the intuition level helps to alleviate the effect of noises. A practical magnetic resonance image data set is used for image segmentation experiment and the performance is compared with those of some conventional algorithms. Results show that the segmentation method based on FCM-I compares favorably to several conventional clustering algorithms. Since FCM-I produces cluster prototypes less sensitive to noises and to the selection of involved parameters than the other algorithms, FCM-I is a good candidate for image segmentation problems.

An eigenspace projection clustering method for structural damage detection

  • Zhu, Jun-Hua;Yu, Ling;Yu, Li-Li
    • Structural Engineering and Mechanics
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    • v.44 no.2
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    • pp.179-196
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    • 2012
  • An eigenspace projection clustering method is proposed for structural damage detection by combining projection algorithm and fuzzy clustering technique. The integrated procedure includes data selection, data normalization, projection, damage feature extraction, and clustering algorithm to structural damage assessment. The frequency response functions (FRFs) of the healthy and the damaged structure are used as initial data, median values of the projections are considered as damage features, and the fuzzy c-means (FCM) algorithm are used to categorize these features. The performance of the proposed method has been validated using a three-story frame structure built and tested by Los Alamos National Laboratory, USA. Two projection algorithms, namely principal component analysis (PCA) and kernel principal component analysis (KPCA), are compared for better extraction of damage features, further six kinds of distances adopted in FCM process are studied and discussed. The illustrated results reveal that the distance selection depends on the distribution of features. For the optimal choice of projections, it is recommended that the Cosine distance is used for the PCA while the Seuclidean distance and the Cityblock distance suitably used for the KPCA. The PCA method is recommended when a large amount of data need to be processed due to its higher correct decisions and less computational costs.

Optimization of Fuzzy Learning Machine by Using Particle Swarm Optimization (PSO 알고리즘을 이용한 퍼지 Extreme Learning Machine 최적화)

  • Roh, Seok-Beom;Wang, Jihong;Kim, Yong-Soo;Ahn, Tae-Chon
    • Journal of the Korean Institute of Intelligent Systems
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    • v.26 no.1
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    • pp.87-92
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    • 2016
  • In this paper, optimization technique such as particle swarm optimization was used to optimize the parameters of fuzzy Extreme Learning Machine. While the learning speed of conventional neural networks is very slow, that of Extreme Learning Machine is very fast. Fuzzy Extreme Learning Machine is composed of the Extreme Learning Machine with very fast learning speed and fuzzy logic which can represent the linguistic information of the field experts. The general sigmoid function is used for the activation function of Extreme Learning Machine. However, the activation function of Fuzzy Extreme Learning Machine is the membership function which is defined in the procedure of fuzzy C-Means clustering algorithm. We optimize the parameters of the membership functions by using optimization technique such as Particle Swarm Optimization. In order to validate the classification capability of the proposed classifier, we make several experiments with the various machine learning datas.

Improved Fuzzy Clusteirng (개선된 퍼지 클러스터링)

  • Kim Sung-Suk;Kim Sung-Soo;Ryu Jeong-Woong
    • Journal of the Korean Institute of Intelligent Systems
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    • v.15 no.1
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    • pp.6-11
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    • 2005
  • In this paper, we propose a new fuzzy clustering scheme that optimizes the initial structure and the parameters to improve the performance of a intelligent systems. The proposed method keeps the good properties of clustering, and improves the total systems' performance at the same time, Especially, the proposed algorithm not only keeps robust to change threshold value in the optimization process, but also improves the performance of a system through the process of the self-organizing and the converging intelligent systems in its structure of cluster. In experiments, the superiority of the proposed scheme is presented by comparing its performance with other methods.

Design of RBFNN-Based Pattern Classifier for the Classification of Precipitation/Non-Precipitation Cases (강수/비강수 사례 분류를 위한 RBFNN 기반 패턴분류기 설계)

  • Choi, Woo-Yong;Oh, Sung-Kwun;Kim, Hyun-Ki
    • Journal of the Korean Institute of Intelligent Systems
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    • v.24 no.6
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    • pp.586-591
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    • 2014
  • In this study, we introduce Radial Basis Function Neural Networks(RBFNNs) classifier using Artificial Bee Colony(ABC) algorithm in order to classify between precipitation event and non-precipitation event from given radar data. Input information data is rebuilt up through feature analysis of meteorological radar data used in Korea Meteorological Administration. In the condition phase of the proposed classifier, the values of fitness are obtained by using Fuzzy C-Mean clustering method, and the coefficients of polynomial function used in the conclusion phase are estimated by least square method. In the aggregation phase, the final output is obtained by using fuzzy inference method. The performance results of the proposed classifier are compared and analyzed by considering both QC(Quality control) data and CZ(corrected reflectivity) data being used in Korea Meteorological Administration.

The Design of Optimal Fuzzy-Neural networks Structure by Means of GA and an Aggregate Weighted Performance Index (유전자 알고리즘과 합성 성능지수에 의한 최적 퍼지-뉴럴 네트워크 구조의 설계)

  • Oh, Sung-Kwun;Yoon, Ki-Chan;Kim, Hyun-Ki
    • Journal of Institute of Control, Robotics and Systems
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    • v.6 no.3
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    • pp.273-283
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    • 2000
  • In this paper we suggest an optimal design method of Fuzzy-Neural Networks(FNN) model for complex and nonlinear systems. The FNNs use the simplified inference as fuzzy inference method and Error Back Propagation Algorithm as learning rule. And we use a HCM(Hard C-Means) Clustering Algorithm to find initial parameters of the membership function. The parameters such as parameters of membership functions learning rates and momentum weighted value is proposed to achieve a sound balance between approximation and generalization abilities of the model. According to selection and adjustment of a weighting factor of an aggregate objective function which depends on the number of data and a certain degree of nonlinearity (distribution of I/O data we show that it is available and effective to design and optimal FNN model structure with a mutual balance and dependency between approximation and generalization abilities. This methodology sheds light on the role and impact of different parameters of the model on its performance (especially the mapping and predicting capabilities of the rule based computing). To evaluate the performance of the proposed model we use the time series data for gas furnace the data of sewage treatment process and traffic route choice process.

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Multiobjective Space Search Optimization and Information Granulation in the Design of Fuzzy Radial Basis Function Neural Networks

  • Huang, Wei;Oh, Sung-Kwun;Zhang, Honghao
    • Journal of Electrical Engineering and Technology
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    • v.7 no.4
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    • pp.636-645
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    • 2012
  • This study introduces an information granular-based fuzzy radial basis function neural networks (FRBFNN) based on multiobjective optimization and weighted least square (WLS). An improved multiobjective space search algorithm (IMSSA) is proposed to optimize the FRBFNN. In the design of FRBFNN, the premise part of the rules is constructed with the aid of Fuzzy C-Means (FCM) clustering while the consequent part of the fuzzy rules is developed by using four types of polynomials, namely constant, linear, quadratic, and modified quadratic. Information granulation realized with C-Means clustering helps determine the initial values of the apex parameters of the membership function of the fuzzy neural network. To enhance the flexibility of neural network, we use the WLS learning to estimate the coefficients of the polynomials. In comparison with ordinary least square commonly used in the design of fuzzy radial basis function neural networks, WLS could come with a different type of the local model in each rule when dealing with the FRBFNN. Since the performance of the FRBFNN model is directly affected by some parameters such as e.g., the fuzzification coefficient used in the FCM, the number of rules and the orders of the polynomials present in the consequent parts of the rules, we carry out both structural as well as parametric optimization of the network. The proposed IMSSA that aims at the simultaneous minimization of complexity and the maximization of accuracy is exploited here to optimize the parameters of the model. Experimental results illustrate that the proposed neural network leads to better performance in comparison with some existing neurofuzzy models encountered in the literature.

A New Fuzzy Clustering Algorithm (새로운 퍼지 군집화 알고리즘)

  • Kim, Jae-Young;Park, Dong-Chul;Han, Ji-Ho;Thuy, Huynh Thi Thanh;Song, Young-Soo
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.1905_1906
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    • 2009
  • 본 논문은 데이터의 군집화를 효율적으로 수행하기 위하여 새로운 군집화 알고리즘을 제안한다. 제안되는 군집화 알고리즘은 Fuzzy C-Means (FCM)에 기반을 두는데, FCM 알고리즘은 모든 데이터에 대한 거리에 기본을 둔 멤버쉽을 기초로 하기 때문에 잡음에 약한 제약을 지니고 있었다. 이를 개선하기 위하여, 제안되었던 PCM(Probabilistic C-Means), FPCM(Fuzzy PCM), PFCM(Probabilistic FCM) 등 여러가지 알고리즘이 제안 되었다. 그러나 이들 알고리즘들은 초기 파라미터값 설정과 과다한 계산양에 따른 문제가 증가하였으며, 또한 잡음에 어느 정도 민감한 문제점을 지니고 있었다. 이 논문에서는 잡음에 대해 효과적으로 대응할 수 있는 새로운 군집화 알고리즘을 제안하고, 전통적인 군집화를 위한 Iris 데이터에 대한 실험을 통하여 효용성을 확인하였다.

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Analysis of Combined Yeast Cell Cycle Data by Using the Integrated Analysis Program for DNA chip (DNA chip 통합분석 프로그램을 이용한 효모의 세포주기 유전자 발현 통합 데이터의 분석)

  • 양영렬;허철구
    • KSBB Journal
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    • v.16 no.6
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    • pp.538-546
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    • 2001
  • An integrated data analysis program for DNA chip containing normalization, FDM analysis, various kinds of clustering methods, PCA, and SVD was applied to analyze combined yeast cell cycle data. This paper includes both comparisons of some clustering algorithms such as K-means, SOM and furry c-means and their results. For further analysis, clustering results from the integrated analysis program was used for function assignments to each cluster and for motif analysis. These results show an integrated analysis view on DNA chip data.

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A new Design of Granular-oriented Self-organizing Polynomial Neural Networks (입자화 중심 자기구성 다항식 신경 회로망의 새로운 설계)

  • Oh, Sung-Kwun;Park, Ho-Sung
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.61 no.2
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    • pp.312-320
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    • 2012
  • In this study, we introduce a new design methodology of a granular-oriented self-organizing polynomial neural networks (GoSOPNNs) that is based on multi-layer perceptron with Context-based Polynomial Neurons (CPNs) or Polynomial Neurons (PNs). In contrast to the typical architectures encountered in polynomial neural networks (PNN), our main objective is to develop a methodological design strategy of GoSOPNNs as follows : (a) The 1st layer of the proposed network consists of Context-based Polynomial Neuron (CPN). In here, CPN is fully reflective of the structure encountered in numeric data which are granulated with the aid of Context-based Fuzzy C-Means (C-FCM) clustering method. The context-based clustering supporting the design of information granules is completed in the space of the input data while the build of the clusters is guided by a collection of some predefined fuzzy sets (so-called contexts) defined in the output space. (b) The proposed design procedure being applied at each layer of GoSOPNN leads to the selection of preferred nodes of the network (CPNs or PNs) whose local characteristics (such as the number of contexts, the number of clusters, a collection of the specific subset of input variables, and the order of the polynomial) can be easily adjusted. These options contribute to the flexibility as well as simplicity and compactness of the resulting architecture of the network. For the evaluation of performance of the proposed GoSOPNN network, we describe a detailed characteristic of the proposed model using a well-known learning machine data(Automobile Miles Per Gallon Data, Boston Housing Data, Medical Image System Data).