• Title/Summary/Keyword: Deterministic Algorithm

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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.

Autonomous control of bicycle using Deep Deterministic Policy Gradient Algorithm (Deep Deterministic Policy Gradient 알고리즘을 응용한 자전거의 자율 주행 제어)

  • Choi, Seung Yoon;Le, Pham Tuyen;Chung, Tae Choong
    • Convergence Security Journal
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    • v.18 no.3
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    • pp.3-9
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    • 2018
  • The Deep Deterministic Policy Gradient (DDPG) algorithm is an algorithm that learns by using artificial neural network s and reinforcement learning. Among the studies related to reinforcement learning, which has been recently studied, the D DPG algorithm has an advantage of preventing the cases where the wrong actions are accumulated and affecting the learn ing because it is learned by the off-policy. In this study, we experimented to control the bicycle autonomously by applyin g the DDPG algorithm. Simulation was carried out by setting various environments and it was shown that the method us ed in the experiment works stably on the simulation.

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A ROUTE-BASED SOLUTION ALGORITHM FOR DYNAMIC USER EQUILIBRIUM ASSIGNMENT (경로기반 해법알고리즘을 이용한 동적통행배분모형의 개발)

  • Sangjin Han
    • Proceedings of the KOR-KST Conference
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    • 2002.02a
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    • pp.97-139
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    • 2002
  • The aim of the present study is to find a good quality user equilibrium assignments under time varying condition. For this purpose, this study introduces a dynamic network loading method that can maintain correct flow propagation as well as flow conservation, and it develops a novel solution algorithm that does not need evaluation of the objective function by modifying the Schittenhelm (1990)'s algorithm. This novel algorithm turns out to be efficient and convenient compared to the conventional Frank-Wolfe (1956) algorithm because the former finds solutions based on routes rather than links so that it can maintain correct flow propagation intrinsically in the time-varying network conditions. The application of dynamic user equilibrium (DUE) assignment model with this novel solution algorithm to test networks including medium-sized one shows that the present DUE assignment model gives rise to high quality discrete time solutions when we adopt the deterministic queuing model for a link performance function, and we associate flows and costs in a proper way.

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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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Deterministic Disturbance Rejection for Model Reference Adaptive Control (결정론적 외란에 대한 적응제어 알고리즘의 연구)

  • Kim, Yong-Sei;Feng, G.;Lee, Kwon-S.
    • Proceedings of the KIEE Conference
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    • 1993.07a
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    • pp.341-344
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    • 1993
  • This paper presents the general MRAC algorithm design, it's real time implementation and investigates the effect of purely deterministic disturbances to adaptive control algorithm. The design of adaptive control algorithm to reject the disturbances properly is also presented. In real time application, adaptive control algorithm is considered to investigate its performance by using DC motor. Disturbance rejection algorithm is investigated in simulation.

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Optimization Algorithm for Real-time Load Dispatch Problem Using Shut-off and Swap Method (발전정지와 교환방법을 적용한 실시간급전문제 최적화 알고리즘)

  • Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.17 no.4
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    • pp.219-224
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    • 2017
  • In facing the lack of a deterministic algorithm for economic load dispatch optimization problem, only non-deterministic heuristic algorithms have been suggested. Worse still, there is a near deficiency of research devoted to real-time load dispatch optimization algorithm. In this paper, therefore, I devise a shut-off and swap algorithm to solve real-time load dispatch optimization problem. With this algorithm in place, generators with maximum cost-per-unit generation power are to be shut off. The proposed shut-off criteria use only quadratic function in power generation cost function without valve effect nonlinear absolute function. When applied to the most prevalent economic load dispatch benchmark data, the proposed algorithm is proven to largely reduce the power cost of known algorithms.

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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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 Study on the File Allocation in Distributed Computer Systems (분산 컴퓨터 시스템에서 파일 할당에 관한 연구)

  • 홍진표;임재택
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.27 no.4
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    • pp.571-579
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    • 1990
  • A dynamic relocation algorithm for non-deterministic process graph in distributed computer systems is proposed. A method is represented for determining the optimal policy for processing a process tree. A general database query request is modelled by a process tree which represent a set of subprocesses together with their precedence relationship. The process allocation model is based on operating cost which is a function fo selection of site for processing operation, data reduction function and file size. By using expected values of parameters for non-deterministic process tree, the process graph and optimal policy that yield minimum operating cost are determined. As process is relocated according to threshold value and new information of parameters after the execution of low level process for non-deterministic process graph, the assigned state that approximate to optiaml solution is obtained. The proposed algorihtm is heuristic By performing algorithm for sample problems, it is shown that the proposed algorithm is good in obtaining optimal solution.

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