K-Means and EM algorithms are the most well-known clustering algorithms because they are simple, easy to understand and implement. However, both algorithms are sensitive to initial seeds which are randomly selected le...
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ISBN:
(纸本)9781450366427
K-Means and EM algorithms are the most well-known clustering algorithms because they are simple, easy to understand and implement. However, both algorithms are sensitive to initial seeds which are randomly selected leading to slow convergence and less reliable clustering results. In this paper, an improved initialization method adopted the concept of light intensity and firefly movement to search for better initial seeds. Numerical experiments were conducted to evaluate the performance of the Enhanced K-Means and EM using faculty performance evaluation ratings as the dataset. The experiments showed that the implementation of the improved initialization method before the clustering process resulted in a higher intra-cluster and lower inter-cluster similarity. Also, there are fifty-nine percent (59%) and sixty-three percent (63%) decrease in the runtime execution while there are forty-four percent (44%) and twenty-seven percent (27%) fewer number of iterations recorded in the implementation of the enhanced KMeans and EM algorithms respectively.
An adaptive soft sensor modeling method based on weighted supervised latent factor analysis is proposed. In conventional moving window based adaptive soft sensor, predictive model is constructed only with the latest p...
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An adaptive soft sensor modeling method based on weighted supervised latent factor analysis is proposed. In conventional moving window based adaptive soft sensor, predictive model is constructed only with the latest process information. To fully take advantage of the past windows, a set of recent local models are integrated by the Hayes' rule for quality estimation However, the former built models may contain similar information about the process, and the redundancy would increase the calculation with a low-efficient accuracy improvement. Then a selecting method is proposed through a statistical hypothesis testing to determine whether a window dataset should be retained or not. In this way, the mostly informative models are left to integrate an efficient predictive model. A real industrial case demonstrates the feasibility and efficiency of the proposed adaptive soft sensor. (C) 2017, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved.
A Remote Sensing image change detection method based on contexture information is proposed. The difference image is constructed by PCA and subtraction operation. Firstly, the Hidden Markov Random Field (HMRF) model is...
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ISBN:
(纸本)9783642319181;9783642319198
A Remote Sensing image change detection method based on contexture information is proposed. The difference image is constructed by PCA and subtraction operation. Firstly, the Hidden Markov Random Field (HMRF) model is applied to characterize the contexture-dependent information, and the Energy function of system is defined. Secondly, the Greedy EM algorithm is used to overcome the disadvantage of the EM algorithm that assumed the number of the mixture components is a known priori, the performance of the overall parameter estimation process depends on the given good initial settings excessively, and the estimated parameter can be resulted from some local optimum points. The distribution model structure and parameters are learned accurately to finds the best fit of the given data. Finally the changed area is obtained by using Iterated Conditional Modes (ICM) to optimize the energy function. Experiments show that the proposed method has virtues of preserving structural change and filtering noises.
Incremental expectationmaximization (EM) algorithms were introduced to design EM for the large scale learning framework by avoiding the full data set to be processed at each iteration. Nevertheless, these algorithms ...
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ISBN:
(纸本)9781728157672
Incremental expectationmaximization (EM) algorithms were introduced to design EM for the large scale learning framework by avoiding the full data set to be processed at each iteration. Nevertheless, these algorithms all assume that the conditional expectations of the sufficient statistics are explicit. In this paper, we propose a novel algorithm named Perturbed Prox-Preconditioned SPIDER (3P-SPIDER), which builds on the Stochastic Path Integral Differential EstimatoR EM (SPIDER-EM) algorithm. The 3P-SPIDER algorithm addresses many intractabilities of the E-step of EM;it also deals with non-smooth regularization and convex constraint set. Numerical experiments show that 3P-SPIDER outperforms other incremental EM methods and discuss the role of some design parameters.
In this paper, we present a new system to segment and label document images by combining statistical and multiscale view of different image components. Texture of text, halftone and images are characterized by modelin...
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ISBN:
(纸本)9780892082797
In this paper, we present a new system to segment and label document images by combining statistical and multiscale view of different image components. Texture of text, halftone and images are characterized by modeling the distribution of a novel intensity projection technique using a mixture of K Gaussians. Model parameters are then estimated using the expectationmaximization (EM) algorithm. Using the proposed algorithm, halftone areas were successfully differentiated from text regions
Two different types of measurements are often available for the key quality variables in process industries- (a) an accurate "slow-rate" laboratory measurements, and (b) a less accurate "fast-rate"...
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Two different types of measurements are often available for the key quality variables in process industries- (a) an accurate "slow-rate" laboratory measurements, and (b) a less accurate "fast-rate" online analyser measurements. Also, the analyser measurements are prone to fail due to hardware issues. Therefore, the main objective of this work is to present a novel approach for developing an accurate, fast-rate, inferential model of quality variables which is robust to outliers. For this purpose, we present a maximum likelihood based approach to integrate the multi-rate output data in the model building task, using expectation maximization algorithm. The efficacy of the proposed approach is demonstrated using a simulation example. (C) 2017, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved.
Two different types of measurements are often available for the key quality variables in process industries - (a) an accurate “slow-rate” laboratory measurements, and (b) a less accurate “fast-rate” online analyse...
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A statistical object detection and tracking mutual feedback scheme, combining Gaussian mixture model (GMM) based on principal component analysis (PCA) and expectationmaximization (EM) Kalman filter algorithm, is prop...
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ISBN:
(纸本)9781424435296
A statistical object detection and tracking mutual feedback scheme, combining Gaussian mixture model (GMM) based on principal component analysis (PCA) and expectationmaximization (EM) Kalman filter algorithm, is proposed in this paper. In space object detection stage, PCA provides compact and decorrelated feature space, the tracked object feature is statistically represented as GMM in RGB color space, objects are detected by maximum a posteriori (MAP) estimation. In temporal tracking stage, the tracked object is determined by the Bhattacharyya similarity measurement, the object position of consecutive frame is predicted by EM Kalman filter algorithm. The integration of object detection and tracking spatio-temporal mutual feedback scheme can decrease the accumulation error. We have applied the proposed method to object detection and tracking under the partial occlusion and the changes of moving speed with encouraging results.
We examine the state entropy optimization in both discounted and average Markov decision processes (MDPs). We suggest a total entropy optimization in a discounted setting, and solve both the entropy rate optimization ...
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ISBN:
(纸本)9798350358513;9798350358520
We examine the state entropy optimization in both discounted and average Markov decision processes (MDPs). We suggest a total entropy optimization in a discounted setting, and solve both the entropy rate optimization and the total discounted entropy optimization with iterative algorithms. An optimal solution to entropy maximization ensures that the system remains as unpredictable as possible. Previous works apply nonlinear programming methods to either the total entropy or entropy rate optimizations. We present both value iteration and policy iteration for synthesizing entropy optimizing policies in ergodic MDPs. For each state in each iteration, the action distribution is optimized with convex optimization in entropy maximization problems. We illustrate the validity of the proposed algorithms in a numerical experiment.
In this paper a study of several cluster validity indices for real-life data sets is presented. Moreover, a new version of validity index is also proposed. All these indices can be considered as a measure of data part...
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ISBN:
(数字)9783319590608
ISBN:
(纸本)9783319590608;9783319590592
In this paper a study of several cluster validity indices for real-life data sets is presented. Moreover, a new version of validity index is also proposed. All these indices can be considered as a measure of data partitioning accuracy and the performance of them is demonstrated for real-life data sets, where three popular algorithms have been applied as underlying clustering techniques, namely the Complete-linkage, expectationmaximization and K-means algorithms. The indices have been compared taking into account the number of clusters in a data set. The results are useful to choose the best validity index for a given data set.
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