• Title/Summary/Keyword: random search

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Optimum Allocation of Pipe Support Using Combined Optimization Algorithm by Genetic Algorithm and Random Tabu Search Method (유전알고리즘과 Random Tabu 탐색법을 조합한 최적화 알고리즘에 의한 배관지지대의 최적배치)

  • 양보석;최병근;전상범;김동조
    • Journal of the Korean Institute of Intelligent Systems
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    • v.8 no.3
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    • pp.71-79
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    • 1998
  • This paper introduces a new optimization algorithm which is combined with genetic algorithm and random tabu search method. Genetic algorithm is a random search algorithm which can find the global optimum without converging local optimum. And tabu search method is a very fast search method in convergent speed. The optimizing ability and convergent characteristics of a new combined optimization algorithm is identified by using a test function which have many local optimums and an optimum allocation of pipe support. The caculation results are compared with the existing genetic algorithm.

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Nonlinear control system using universal learning network with random search method of variable search length

  • Shao, Ning;Hirasawa, Kotaro;Ohbayashi, Masanao;Togo, Kazuyuki
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10a
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    • pp.235-238
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    • 1996
  • In this paper, a new optimization method which is a kind of random searching is presented. The proposed method is called RasVal which is an abbreviation of Random Search Method with Variable Seaxch Length and it can search for a global minimum based on the probability density functions of searching, which can be modified using informations on success or failure of the past searching in order to execute intensified and diversified searching. By applying the proposed method to a nonlinear crane control system which can be controlled by the Universal Learning Network with radial basis function(R.B.P.), it has been proved that RasVal is superior in performance to the commonly used back propagation learning algorithm.

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Development and Testing of a New Area Search Model with Partially Overlapping Target and Searcher Patrol Area

  • Kim, Gi-Young;Eagle, James N.;Kang, Sung-Jin
    • Journal of the military operations research society of Korea
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    • v.35 no.1
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    • pp.21-32
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    • 2009
  • In this study, the author uses a MATLAB simulation to develop and test a generalization of the traditional Random Search model which allows both the searcher and target to move and to be in different, but overlapping, areas. Also the best evasion speed for a randomly moving target against a Systematic Search is studied.

Linear Inversion of Heat Flow Data (지각열류량(地殼熱流量)의 선형(線型) 반전(反轉))

  • Han, Wook
    • Economic and Environmental Geology
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    • v.17 no.3
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    • pp.163-169
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    • 1984
  • A linear inversion of heat flow values using heat production data with reliable value is studied in this work. To evaluate 2-D problem, a thin vertical sheet model is considered. Making use of a relation based on potential theory, a new relation between $q_{rad}$ and $A_0$ is derived. The forward calculations with noise and without noise are shown. The inversion of random search is comparable to that of ridge regression method. The agreements between the computed and best fit after inversion suggest the importance of random search method in the inversion technique.

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High Order Template Scheme for Rapid Acquisition in the UWB Communication System (고차 모델을 사용한 광대역 통신 시스템의 새로운 고속 동기화 기법)

  • Baasantseren, Gansuren;Lin, Xiaoju;Lee, Hae-Kee;Kim, Sung-Soo
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.59 no.1
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    • pp.47-52
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    • 2010
  • The low power of ultra-wideband (UWB) signal makes the acquisition of UWB signal be a more challenging task. In this paper, we propose the method of high order template signal technique that reduces the synchronization time. Experimental results are presented to show the improvements of performance in the mean acquisition time (MAT) and the probability of detection. The performance compared with the serial search, the truly random search and the random permutation search. It is shown that over typical UWB multipath channels, a random permutation search scheme may yield lower MAT than serial search.

Ooptimum Design Damping Plate by Combined Method of Genetic Algorithm and Random Tabu Search Method (유전알고리즘과 Tabu탐색법에 의한 제진판의 최적설계)

  • 양보석;전상범;유영훈;최병근
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1997.10a
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    • pp.184-189
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    • 1997
  • This paper introduces a new combined method by genetic algorithm and random tabu search method as optimization algorithm. Genetic algorithm can search the global optimum and tabu search method is very fast in speed. The optimizing ability of new combined method is identified by comparing other optimizing algorithm and used for optimum design of damping plate.

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Visual Search Models for Multiple Targets and Optimal Stopping Time (다수표적의 시각적 탐색을 위한 탐색능력 모델과 최적 탐색정지 시점)

  • Hong, Seung-Kweon;Park, Seikwon;Ryu, Seung Wan
    • Journal of Korean Institute of Industrial Engineers
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    • v.29 no.2
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    • pp.165-171
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    • 2003
  • Visual search in an unstructured search field is a fruitful research area for computational modeling. Search models that describe relationship between search time and probability of target detection have been used for prediction of human search performance and provision of ideal goals for search training. Until recently, however, most of models were focused on detecting a single target in a search field, although, in practice, a search field includes multiple targets and search models for multiple targets may differ from search models for a single target. This study proposed a random search model for multiple targets, generalizing a random search model for a single target which is the most typical search model. To test this model, human search data were collected and compared with the model. This model well predicted human performance in visual search for multiple targets. This paper also proposed how to determine optimal stopping time in multiple-target search.

Derivative Evaluation and Conditional Random Selection for Accelerating Genetic Algorithms

  • Jung, Sung-Hoon
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.5 no.1
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    • pp.21-28
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    • 2005
  • This paper proposes a new method for accelerating the search speed of genetic algorithms by taking derivative evaluation and conditional random selection into account in their evolution process. Derivative evaluation makes genetic algorithms focus on the individuals whose fitness is rapidly increased. This accelerates the search speed of genetic algorithms by enhancing exploitation like steepest descent methods but also increases the possibility of a premature convergence that means most individuals after a few generations approach to local optima. On the other hand, derivative evaluation under a premature convergence helps genetic algorithms escape the local optima by enhancing exploration. If GAs fall into a premature convergence, random selection is used in order to help escaping local optimum, but its effects are not large. We experimented our method with one combinatorial problem and five complex function optimization problems. Experimental results showed that our method was superior to the simple genetic algorithm especially when the search space is large.

Likelihood search method with variable division search

  • Koga, Masaru;Hirasawa, Kotaro;Murata, Junichi;Ohbayashi, Masanao
    • 제어로봇시스템학회:학술대회논문집
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    • 1995.10a
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    • pp.14-17
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    • 1995
  • Various methods and techniques have been proposed for solving optimization problems; the methods have been applied to various practical problems. However the methods have demerits. The demerits which should be covered are, for example, falling into local minima, or, a slow convergence speed to optimal points. In this paper, Likelihood Search Method (L.S.M.) is proposed for searching for a global optimum systematically and effectively in a single framework, which is not a combination of different methods. The L.S.M. is a sort of a random search method (R.S.M.) and thus can get out of local minima. However exploitation of gradient information makes the L.S.M. superior in convergence speed to the commonly used R.S.M..

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