Adaptive k-means clustering algorithms have been used in several artificial neural network architectures, such as radial basis function networks or feature-map classifiers, for a competitive partitioning of the input ...
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Adaptive k-means clustering algorithms have been used in several artificial neural network architectures, such as radial basis function networks or feature-map classifiers, for a competitive partitioning of the input domain. This paper presents an enhancement of the traditional k-means algorithm. It approximates an optimal clustering solution with an efficient adaptive learning rate, which renders it usable even in situations where the statistics of the problem task varies slowly with time. This modification is based on the optimality criterion for the k-means partition stating that: all the regions in an optimal k-means partition have the same variations if the number of regions in the partition is large and the underlying distribution for generating input patterns Is smooth. The goal of equalizing these variations is introduced in the competitive function that assigns each new pattern vector to the ''appropriate'' region. To evaluate the optimal k-means algorithm, we first compare it to other k-means variants on several simple tutorial examples, then we evaluate it on a practical application: vector quantization of image data.
The IoT and Artificial intelligence, the amount of information generated on the Web site is increasing. The rise of the Hadoop distributed cloud computing platform (HDCCP) makes it possible to use multiple computing n...
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The IoT and Artificial intelligence, the amount of information generated on the Web site is increasing. The rise of the Hadoop distributed cloud computing platform (HDCCP) makes it possible to use multiple computing nodes for parallel computing to solve the performance problems of traditional serial algorithms. The purpose of this paper is to study data design based on cloud computing and improved k-means algorithm (kMA). This paper deeply researches Hadoop distributed cloud computing platform and clustering algorithm and other related technologies, and designs and implements a cluster analysis system (CAS) based on HP. And through an in-depth analysis of the problems existing in the kMA, an improved scheme based on the HDP is designed. The experimental environment was conFig.d with the cluster analysis system implemented. Finally, the improved kMPA was tested experimentally from four directions: convergence speed, acceleration ratio, initialization sampling rate, and accuracy rate. We can see the experimental results that the CAS based on the HDCCP designed in this paper can provide efficient and configurable cluster analysis services. In this paper, the correct rate is 90.7%.
In this paper, a weight selection procedure in the W-k-means algorithm is proposed based on the statistical variation viewpoint. This approach can solve the W-k-means algorithm's problem that the clustering qualit...
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In this paper, a weight selection procedure in the W-k-means algorithm is proposed based on the statistical variation viewpoint. This approach can solve the W-k-means algorithm's problem that the clustering quality is greatly affected by the initial value of weight. After the statistics of data, the weights of data are designed to provide more information for the character of W-k-means algorithm so as to improve the precision. Furthermore, the corresponding computational complexity is analyzed as well. We compare the clustering results of the W-k-means algorithm with the different initialization methods. Results from color image segmentation illustrate that the proposed procedure produces better segmentation than the random initialization according to Liu and Yang's (1994) evaluation function. (C) 2011 Elsevier Ltd. All rights reserved.
The k-means algorithm and its variations are known to be fast clustering algorithms. However, they are sensitive to the choice of starting points and are inefficient for solving clustering problems in large datasets. ...
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The k-means algorithm and its variations are known to be fast clustering algorithms. However, they are sensitive to the choice of starting points and are inefficient for solving clustering problems in large datasets. Recently, incremental approaches have been developed to resolve difficulties with the choice of starting points. The global k-means and the modified global k-means algorithms are based on such an approach. They iteratively add one cluster center at a time. Numerical experiments show that these algorithms considerably improve the k-means algorithm. However, they require storing the whole affinity matrix or computing this matrix at each iteration. This makes both algorithms time consuming and memory demanding for clustering even moderately large datasets. In this paper, a new version of the modified global k-means algorithm is proposed. We introduce an auxiliary cluster function to generate a set of starting points lying in different parts of the dataset. We exploit information gathered in previous iterations of the incremental algorithm to eliminate the need of computing or storing the whole affinity matrix and thereby to reduce computational effort and memory usage. Results of numerical experiments on six standard datasets demonstrate that the new algorithm is more efficient than the global and the modified global k-means algorithms. (C) 2010 Elsevier Ltd. All rights reserved.
Block truncation coding (BTC) is an efficient image compression method which finds application in diverse fields. The basic problem can be viewed as a two-level quantization process. However, efficient ways for optima...
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Block truncation coding (BTC) is an efficient image compression method which finds application in diverse fields. The basic problem can be viewed as a two-level quantization process. However, efficient ways for optimal threshold determination have not been discovered so far. We propose a fast BTC algorithm based on a truncated k-means algorithm, utilizing the image inter-block correlation and the fact that k-means algorithm converges very fast in this case. This produces near-optimum solution with significantly improved speed over other methods. Simulation results confirm such advantages. (C) 2010 Elsevier GmbH. All rights reserved.
Recently a modified k-means algorithm for vector quantization design has been proposed where the codevector updating step is as follows: new codevector = current codevector + scale factor (new centroid - current codev...
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Recently a modified k-means algorithm for vector quantization design has been proposed where the codevector updating step is as follows: new codevector = current codevector + scale factor (new centroid - current codevector), This algorithm uses a fixed value for the scale factor. In this paper, we propose the use of a variable scale factor which is a function of the iteration number. For the vector quantization of image data, we show that it offers faster convergence than the modified k-means algorithm with a fixed scale factor, without affecting the optimality of the codebook.
Conventional algorithms fail to obtain satisfactory background segmentation results for underwater images. In this study, an improved k-means algorithm was developed for underwater image background segmentation to add...
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Conventional algorithms fail to obtain satisfactory background segmentation results for underwater images. In this study, an improved k-means algorithm was developed for underwater image background segmentation to address the issue of improper k value determination and minimize the impact of initial centroid position of grayscale image during the gray level quantization of the conventional k-means algorithm. A total of 100 underwater images taken by an underwater robot were sampled to test the aforementioned algorithm in respect of background segmentation validity and time cost. The k value and initial centroid position of grayscale image were optimized. The results were compared to the other three existing algorithms, including the conventional k-means algorithm, the improved Otsu algorithm, and the Canny operator edge extraction method. The experimental results showed that the improved k-means underwater background segmentation algorithm could effectively segment the background of underwater images with a low color cast, low contrast, and blurred edges. Although its cost in time was higher than that of the other three algorithms, it none the less proved more efficient than the time-consuming manual segmentation method. The algorithm proposed in this paper could potentially be used in underwater environments for underwater background segmentation.
In order to overcome the low accuracy of the traditional method, a fast identification method based on the improved k-mean algorithm is proposed. Spatial grid block model is constructed to extract the fingerprint text...
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In order to overcome the low accuracy of the traditional method, a fast identification method based on the improved k-mean algorithm is proposed. Spatial grid block model is constructed to extract the fingerprint texture features and then the fingerprint profile features are detected using the edge outline extraction method. The kalman fusion method is used to reconstruct fingerprint information. Using the neighbourhood distributed retrieval method, fingerprint image feature fusion is realised and the texture feature extraction model for forged fingerprints is established. The k-means clustering method is used for fingerprint feature clustering to realise fast identification of forged fingerprints. Experimental results show that the identification accuracy of this method is higher than 0.85, and the identification stability is good. The signal-to-noise ratio of fingerprint images is always between 25.3 dB and 82.3 dB, and the imaging quality is high, indicating that this method can realise fast and accurate identification of forged fingerprints.
In this paper, we aim to compare empirically four initialization methods for the k-means algorithm: random, Forgy, MacQueen and kaufman. Although this algorithm is known for its robustness, it is widely reported in th...
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In this paper, we aim to compare empirically four initialization methods for the k-means algorithm: random, Forgy, MacQueen and kaufman. Although this algorithm is known for its robustness, it is widely reported in the literature that its performance depends upon two key points: initial clustering and instance order. We conduct a series of experiments to draw up tin terms of mean, maximum, minimum and standard deviation) the probability distribution of the square-error values of the final clusters returned by the k-means algorithm independently on any initial clustering and on any instance order when each of the four initialization methods is used. The results of our experiments illustrate that the random and the kaufman initialization methods outperform the rest of the compared methods as they make the k-means more effective and more independent on initial clustering and on instance order. In addition, we compare the convergence speed of the k-means algorithm when using each of the four initialization methods. Our results suggest that the kaufman initialization method induces to the k-means algorithm a more desirable behaviour with respect to the convergence speed than the random initialization method. (C) 1999 Elsevier Science B.V. All rights reserved.
The paper presents assumptions and results recorded thanks to the application of a novel method to identify juvenile and mature wood zones in stems of forest trees based on a k-means algorithm. The algorithm showed th...
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The paper presents assumptions and results recorded thanks to the application of a novel method to identify juvenile and mature wood zones in stems of forest trees based on a k-means algorithm. The algorithm showed the boundary between analysed types of wood on the basis of input data based on macroscopic structure of wood, i.e. the width of the annual ring, the proportion of late wood in the annual ring and the length of the ray of the annual ring (the location of the annual ring on the ray). Analyses conducted using this method indicated that juvenile wood in 24 European larches covers from 9 to 22 annual rings located around the pith (on average 13). The applied method was verified by changing the degree of crystallinity of cellulose determined at breast height of 3 mean sample trees. Boundaries indicated by the algorithm coincided with high accuracy with places where the course of changes in values of the degree of crystallinity at successive annual rings started to be similar.
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