clustering is an important unsupervised learning technique to discover the inherent structure of a given data set. In this paper, we propose a novel method to determine optimal classes and select optimal samples in da...
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ISBN:
(纸本)9789814324694
clustering is an important unsupervised learning technique to discover the inherent structure of a given data set. In this paper, we propose a novel method to determine optimal classes and select optimal samples in data sets, the novel method is based on fuzzy c-means algorithm and the k-meansalgorithm. An illustrate example shows that our method is simple and valid for clustering and pattern recognition.
Automated image detection of white matter changes of the brain is essentially helpful in providing a quantitative measure for studying the association of white matter lesions with other types of biomedical data. Such ...
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ISBN:
(纸本)9781424441242
Automated image detection of white matter changes of the brain is essentially helpful in providing a quantitative measure for studying the association of white matter lesions with other types of biomedical data. Such study allows the possibility of several medical hypothesis validations which lead to therapeutic treatment and prevention. This paper presents a new clustering-based segmentation approach for detecting white matter changes in magnetic resonance imaging with particular reference to cognitive decline in the elderly. The proposed method is formulated using the principles of fuzzy.. meansalgorithm and geostatistics.
In this paper, we propose a novel objective function called the adaptive fuzzy Weighted Sum Validity Function (FWSVF), which is a merged weight of the several fuzzycluster validity functions, including XB, PE, Pc...
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In this paper, we propose a novel objective function called the adaptive fuzzy Weighted Sum Validity Function (FWSVF), which is a merged weight of the several fuzzycluster validity functions, including XB, PE, Pc and PBMF. The improved validity function is more efficient than others. Furthermore, we present a Mixed Strategy Evolutionary clustering algorithm based adaptive validity function (AMSEcA), which is merged from Evolutionary algorithm along with Mixed Strategy and fuzzy c-means algorithm. Moreover, in the experiments, we show the effectiveness of AMSEcA, AMSEcA could find the proper number of clusters automatically as well as appropriate partitions of the data set and avoid local optima.
There are two problems for clustering algorithm of classicfuzzyc-means (FcM). First, the algoritbm of FcM often obtains different clustering results with the different initial cluster centers because it is over...
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There are two problems for clustering algorithm of classicfuzzyc-means (FcM). First, the algoritbm of FcM often obtains different clustering results with the different initial cluster centers because it is over-dependent on the initial cluster centers. Second, the algorithm needs to know the actual number of clusters in advance, but in fact the number of clusters is unknown. Tbis paper proposes a solution that we determine a reasonable number and centers of clusters using a weighted Euclidean clustering method, and then use the classical FcM algorithm. It can be significantly reduced the number of algorithm iterations. This method was proved feasibility and effectiveness through the emulation experiment.
This paper presents a formal definition of stable peers, a novel method to separate stable peers from all peers and an analysis of the session sequences of stable peers in P2P (Peer-to-Peer) systems. This study uses t...
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This paper presents a formal definition of stable peers, a novel method to separate stable peers from all peers and an analysis of the session sequences of stable peers in P2P (Peer-to-Peer) systems. This study uses the KAD, a P2P file sharing system with several million simultaneous users, as an example and draws some significant conclusions: (1) large numbers of peers with very short session time usually possess few sessions;(2) the stable peers is about 0.6% of all peers;(3) the 70% of stable peers possess very long total session time ensured by a large number of sessions, and possess large difference between session time;(4) the 30% of stable peers, whose average session time is 1.8 times of the former, possess long total session time, a small number of sessions and high availability. We believe that these two types of stable peers can be used for different functions to solve the churn problem in the hierarchical P2P systems.
In this paper, a fuzzyclustering method based on evolutionary programming (EPFcM) is proposed. The algorithm benefits from the global search strategy of evolutionary programming, to improve fuzzy c-means algorithm (F...
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In this paper, a fuzzyclustering method based on evolutionary programming (EPFcM) is proposed. The algorithm benefits from the global search strategy of evolutionary programming, to improve fuzzy c-means algorithm (FcM). The cluster validity can be measured by some cluster validity indices. To increase the convergence speed of the algorithm, we exploit the modified algorithm to change the number of cluster centers dynamically. Experiments demonstrate EPFcM can find the proper number of clusters, and the result of clustering does not depend critically on the choice of the initial cluster centers. The probability of trapping into the local optima will be very lower than FcM. (c) 2009 Elsevier Ltd. All rights reserved.
This letter presents a new inter-cluster proximity index for fuzzy partitions obtained from the fuzzy c-means algorithm. It is defined as the average proximity of all possible pairs of clusters. The proximity of each ...
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This letter presents a new inter-cluster proximity index for fuzzy partitions obtained from the fuzzy c-means algorithm. It is defined as the average proximity of all possible pairs of clusters. The proximity of each pair of clusters is determined by the overlap and the separation of the two clusters. The former is quantified by using concepts of fuzzy Rough sets theory and the latter by computing the distance between cluster centroids. Experimental results indicate the efficiency of the proposed index.
We discuss the clustering of 234 environmental samples resulting from an extensive monitoring program concerning soil lead content, plant lead content, traffic density, and distance from the road at different sampling...
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We discuss the clustering of 234 environmental samples resulting from an extensive monitoring program concerning soil lead content, plant lead content, traffic density, and distance from the road at different sampling locations in former East Germany. considering the structure of data and the unsatisfactory results obtained applying classical clustering and principal component analysis, it appeared evident that fuzzyclustering could be one of the best solutions. In the following order we used different fuzzyclustering algorithms, namely, the fuzzyc-means (FcM) algorithm, the Gustafson-Kessel (GK) algorithm, which may detect clusters of ellipsoidal shapes in data by introducing an adaptive distance norm for each cluster, and the fuzzyc-varieties (FcV) algorithm, which was developed for recognition of r-dimensional linear varieties in high-dimensional data (lines, planes or hyperplanes). fuzzyclustering with convex combination of point prototypes and different multidimensional linear prototypes is also discussed and applied for the first time in analytical chemistry (environmetrics). The results obtained in this study show the advantages of the FcV and GK algorithms over the FcM algorithm. The performance of each algorithm is illustrated by graphs and evaluated by the values of some conventional cluster validity indices. The values of the validity indices are in very good agreement with the quality of the clustering results.
Unsupervised fuzzyclustering algorithms are one of many approaches used in image segmentation. The fuzzy c-means algorithm (FcM) and the Possibilisticc-meansalgorithm (PIcA) have been widely used. There is also the...
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Unsupervised fuzzyclustering algorithms are one of many approaches used in image segmentation. The fuzzy c-means algorithm (FcM) and the Possibilisticc-meansalgorithm (PIcA) have been widely used. There is also the generalized possibilisticalgorithm (GPcA). GPcA was proposed recently and is a general form of the previous algorithms. These clustering algorithms can be trapped to the local optimal solutions. Hence, optimization techniques are often used in conjunction with algorithms to improve the performance. Some of optimization techniques have been inspired by nature such as swarm behavior. Particle Swarm Optimization (PSO) is one such technique. In this paper, PSO heuristics were combined with FcM, PIcA, and GPcA algorithms to improve the overall clustering accuracy of these algorithms. To test the improvement with the PSO, these algorithms were tested on images. The overall effect of adding unique PSO methods was a higher percentage of satisfactory image segmentations.
The traditional fuzzy: c-means (FcM) algorithm has some disadvantages in optimization method, which makes the algorithm liable to fall into local optimum, thus failing to get the optimal clustering results. According ...
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ISBN:
(纸本)9783540877332
The traditional fuzzy: c-means (FcM) algorithm has some disadvantages in optimization method, which makes the algorithm liable to fall into local optimum, thus failing to get the optimal clustering results. According to the defect of FcM algorithm, a new fuzzyclustering algorithm based on chaos Optimization (FccO) is proposed in this paper, which combines mutative scale, chaos optimization strategy acid gradient method together. Moreover, a fuzzycluster validity index (PBMF) is introduced to make the FccO algorithmcapable of clustering automatically. Three other fuzzycluster validity indices, namely XB, Pc and PE, are utilized to compare the performances of FccO, MINI and another algorithm, when applied to artificial and real data sets classification. Experiment results show FccO algorithm is more likely to obtain the global optimum and achieve Better performances on validity indices than other algorithms.
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