• Title/Summary/Keyword: Deterministic Annealing

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Medoid Determination in Deterministic Annealing-based Pairwise Clustering

  • Lee, Kyung-Mi;Lee, Keon-Myung
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.11 no.3
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    • pp.178-183
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    • 2011
  • The deterministic annealing-based clustering algorithm is an EM-based algorithm which behaves like simulated annealing method, yet less sensitive to the initialization of parameters. Pairwise clustering is a kind of clustering technique to perform clustering with inter-entity distance information but not enforcing to have detailed attribute information. The pairwise deterministic annealing-based clustering algorithm repeatedly alternates the steps of estimation of mean-fields and the update of membership degrees of data objects to clusters until termination condition holds. Lacking of attribute value information, pairwise clustering algorithms do not explicitly determine the centroids or medoids of clusters in the course of clustering process or at the end of the process. This paper proposes a method to identify the medoids as the centers of formed clusters for the pairwise deterministic annealing-based clustering algorithm. Experimental results show that the proposed method locate meaningful medoids.

Segmentation of Color Image Using the Deterministic Anneanling EM Algorithm (결정적 어닐링 EM 알고리즘을 이용한 칼라 영상의 분할)

  • 박종현;박순영;조완현
    • Proceedings of the IEEK Conference
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    • 1999.11a
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    • pp.569-572
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    • 1999
  • In this paper we present a color image segmentation algorithm based on statistical models. A novel deterministic annealing Expectation Maximization(EM) formula is derived to estimate the parameters of the Gaussian Mixture Model(GMM) which represents the multi-colored objects statistically. The experimental results show that the proposed deterministic annealing EM is a global optimal solution for the ML parameter estimation and the image field is segmented efficiently by using the parameter estimates.

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Convergence of MAP-EM Algorithms with Nonquadratic Smoothing Priors

  • Lee, Soo-Jin
    • Proceedings of the KOSOMBE Conference
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    • v.1997 no.11
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    • pp.361-364
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    • 1997
  • Bayesian MAP-EM approaches have been quite useful or tomographic reconstruction in that they can stabilize the instability of well-known ML-EM approaches, and can incorporate a priori information on the underlying emission object. However, MAP reconstruction algorithms with expressive priors often suffer from the optimization problem when their objective unctions are nonquadratic. In our previous work [1], we showed that the use of deterministic annealing method greatly reduces computational burden or optimization and provides a good solution or nonquadratic objective unctions. Here, we further investigate the convergence of the deterministic annealing algorithm; our experimental results show that, while the solutions obtained by a simple quenching algorithm depend on the initial conditions, the estimates converged via deterministic annealing algorithm are consistent under various initial conditions.

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A Development of SDS Algorithm for the Improvement of Convergence Simulation (실시간 계산에서 수령속도 개선을 위한 SDS 알고리즘의 개발)

  • Lee, Young-J.;Jang, Yong-H.;Lee, Kwon-S.
    • Proceedings of the KIEE Conference
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    • 1997.07b
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    • pp.699-701
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    • 1997
  • The simulated annealing(SA) algorithm is a stochastic strategy for search of the ground state and a powerful tool for optimization, based on the annealing process used for the crystallization in physical systems. It's main disadvantage is the long convergence time. Therefore, this paper proposes a stochastic algorithm combined with conventional deterministic optimization method to reduce the computation time, which is called SDS(Stochastic-Deterministic-Stochastic) method.

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Global Optimization of Clusters in Gene Expression Data of DNA Microarrays by Deterministic Annealing

  • Lee, Kwon Moo;Chung, Tae Su;Kim, Ju Han
    • Genomics & Informatics
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    • v.1 no.1
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    • pp.20-24
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    • 2003
  • The analysis of DNA microarry data is one of the most important things for functional genomics research. The matrix representation of microarray data and its successive 'optimal' incisional hyperplanes is a useful platform for developing optimization algorithms to determine the optimal partitioning of pairwise proximity matrix representing completely connected and weighted graph. We developed Deterministic Annealing (DA) approach to determine the successive optimal binary partitioning. DA algorithm demonstrated good performance with the ability to find the 'globally optimal' binary partitions. In addition, the objects that have not been clustered at small non­zero temperature, are considered to be very sensitive to even small randomness, and can be used to estimate the reliability of the clustering.

Bayesian Image Restoration Using a Continuation Method (연속방법을 사용한 Bayesian 영상복원)

  • Lee, Soo-Jin
    • The Journal of Engineering Research
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    • v.3 no.1
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    • pp.65-73
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    • 1998
  • One approach to improved image restoration methods has been the incorporation of additional source information via Gibbs priors that assume a source that is piecewise smooth. A natural Gibbs prior for expressing such constraints is an energy function defined on binary valued line processes as well as source intensities. However, the estimation of both continuous variables and binary variables is known to be a difficult problem. In this work, we consider the application of the deterministic annealing method. Unlike other methods, the deterministic annealing method offers a principled and efficient means of handling the problems associated with mixed continuous and binary variable objectives. The application of the deterministic annealing method results in a sequence of objective functions (defined only on the continuous variables) whose sequence of solutions approaches that of the original mixed variable objective function. The sequence is indexed by a control parameter (the temperature). The energy functions at high temperatures are smooth approximations of the energy functions at lower temperatures. Consequently, it is easier to minimize the energy functions at high temperatures and then track the minimum through the variation of the temperature. This is the essence of a continuation method. We show experimental results, which demonstrate the efficacy of the continuation method applied to a Bayesian restoration model.

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Classification of Magnetic Resonance Imagery Using Deterministic Relaxation of Neural Network (신경망의 결정론적 이완에 의한 자기공명영상 분류)

  • 전준철;민경필;권수일
    • Investigative Magnetic Resonance Imaging
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    • v.6 no.2
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    • pp.137-146
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    • 2002
  • Purpose : This paper introduces an improved classification approach which adopts a deterministic relaxation method and an agglomerative clustering technique for the classification of MRI using neural network. The proposed approach can solve the problems of convergency to local optima and computational burden caused by a large number of input patterns when a neural network is used for image classification. Materials and methods : Application of Hopfield neural network has been solving various optimization problems. However, major problem of mapping an image classification problem into a neural network is that network is opt to converge to local optima and its convergency toward the global solution with a standard stochastic relaxation spends much time. Therefore, to avoid local solutions and to achieve fast convergency toward a global optimization, we adopt MFA to a Hopfield network during the classification. MFA replaces the stochastic nature of simulated annealing method with a set of deterministic update rules that act on the average value of the variable. By minimizing averages, it is possible to converge to an equilibrium state considerably faster than standard simulated annealing method. Moreover, the proposed agglomerative clustering algorithm which determines the underlying clusters of the image provides initial input values of Hopfield neural network. Results : The proposed approach which uses agglomerative clustering and deterministic relaxation approach resolves the problem of local optimization and achieves fast convergency toward a global optimization when a neural network is used for MRI classification. Conclusion : In this paper, we introduce a new paradigm to classify MRI using clustering analysis and deterministic relaxation for neural network to improve the classification results.

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Latent class analysis with multiple latent group variables

  • Lee, Jung Wun;Chung, Hwan
    • Communications for Statistical Applications and Methods
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    • v.24 no.2
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    • pp.173-191
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    • 2017
  • This study develops a new type of latent class analysis (LCA) in order to explain the associations between one latent variable and several other categorical latent variables. Our model postulates that the prevalence of the latent variable of interest is affected by another latent variable composed of other several latent variables. For the parameter estimation, we propose deterministic annealing EM (DAEM) to deal with local maxima problem in the proposed model. We perform simulation study to demonstrate how DAEM can find the set of parameter estimates at the global maximum of the likelihood over the repeated samples. We apply the proposed LCA model in an investigation of the effect of and joint patterns for drug-using behavior to violent behavior among US high school male students using data from the Youth Risk Behavior Surveillance System 2015. Considering the age of male adolescents as a covariate influencing violent behavior, we identified three classes of violent behavior and three classes of drug-using behavior. We also discovered that the prevalence of violent behavior is affected by the type of drug used for drug-using behavior.

An Application of Simulated Annealing Combining Deterministic Search to Optimal Design of Interior Permanent Magnet Synchronous Motors (매입형 영구자석 동기전동기의 최적설계를 위한 시뮬레이티드 애닐링과 결정론적 탐색법의 혼합적용)

  • Sim, Dong-Joon;Jung, Hyun-Kyo;Hahn, Song-Yop;Won, Jong-Soo
    • Proceedings of the KIEE Conference
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    • 1994.07a
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    • pp.159-161
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    • 1994
  • This paper presents a combined algorithm of simulated annealing and determinstic method which overcomes the defects of two methods and guarantees the fast convergence to the global optimum. This optimization method is applied to optimal design of Interior Permanent Magnet Synchronous Motor. And the result of the proposed algorithm is compared with that of simulated annealing alone.

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Generation of Robotic Assembly Aequences with Consideration of Line Balancing Using a Simulated Annealing (조립라인의 밸런싱을 고려한 자동 조립 순서 추론)

  • Hong, Dae-Seon;Jo, Hyeong-Seok
    • Journal of Institute of Control, Robotics and Systems
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    • v.1 no.2
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    • pp.112-118
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    • 1995
  • In designing assembly lines, it is required that the lines should not only meet the demand of the product, but also minimize the assembly cost associated with the line. For such a purpose, numerous research efforts have been made on either the assembly sequence generation or the assembly line balancing. However, the works dealing with both the research problems have been seldom reported in literature. When assembly sequences are generated without consideration of line balancing, additional cost may be incurred, because the sequences may not guarantee the minimum number of workstations. Therefore, it is essential to consider line balancing in the generation of cost-effective assembly sequences. To incorporate the two research problems into one, this paper treats a single-model and deterministic (SMD) assembly line balancing (ALB) problem, and proposes a new method for generating line-balanced robotic assembly sequences by using a simulated annealing. In this method, an energy function is derived in consideration of the satisfaction of assembly constraints, and the minimization of both the assembly cost and the idle time. Then, the energy function is iteratively minimized and occasionally perturbed by the simulated annealing. When no further change in energy occurs, an assembly sequence with consideration of line balancing is finally found. To show the effectiveness of the proposed scheme, a case study for an electrical relay is presented.

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