• Title/Summary/Keyword: SA(Simulated Annealing)

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Simulated-Annealing Improvement Technique Using Compaction and Reverse Algorithm for Floorplanning with Sequence-Pair Model (Sequence-Pair 모델 기반의 블록 배치에서 압축과 배치 역변환을 이용한 Simulated-Annealing 개선 기법)

  • Seong, Young-Tae;Hur, Sung-Woo
    • Proceedings of the Korean Information Science Society Conference
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    • 2008.06b
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    • pp.598-603
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    • 2008
  • Sequence-Pair(SP)는 플로어플랜을 표현하는 모델 중 하나로써, 일반적으로 SP 모델을 사용하는 플로 어프래너 (floorplanner)는 Simulated-Annealing (SA) 알고리즙을 통해 해 탐색 과정을 수행한다. SP 모델을 이용한 다양한 논문에서 플로어플랜 성능 향상을 위해 평가함수의 개선과 스케줄링 기법 향상을 모색하였으며, 평가함수의 경우 O(nlogn) 시간 알고리즘이 존재한다. 본 논문에서는 SP 모델을 이용한 SA 기법에서 SA의 해 탐색 과정 중 초기 해 탐색 시점에서 좋은 해를 빠르게 찾을 수 있는 방법을 제안한다. 제안 기법은 기존의 SA 프레임펙을 수정한 2단계 SA 알고리즘으로써 SP에 대응하는 배치를 압축하고 압축한 배치를 역변환하는 과정으로 구성된다. 실험과 결과를 통해 제안기법의 효과를 보이며, 평균적으로 동일한 SA 환경 하에서 제안기법이 최종결과 면에서 우수함을 보인다.

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A Proposal of Combined Iterative Algorithm for Optimal Design of Binary Phase Computer Generated Hologram (최적의 BPCGH 설계를 위한 합성 반복 알고리듬 제안)

  • Kim Cheol-Su
    • Journal of Korea Society of Industrial Information Systems
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    • v.10 no.4
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    • pp.16-25
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    • 2005
  • In this paper, we proposed a novel algorithm combined simulated annealing and genetic algorithms for designing optimal binary phase computer generated hologram. In the process of genetic algorithm searching by block units, after the crossover and mutation operations, simulated annealing algorithm searching by pixel units is inserted. So, the performance of BPCGH was improved. Computer simulations show that the proposed combined iterative algorithm has better performance than the simulated annealing algorithm in terms of diffraction efficiency

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The Real-time Path Planning Using Artificial Potential Field and Simulated Annealing for Mobile Robot (Artificial Potential Field 와 Simulated Annealing을 이용한 이동로봇의 실시간 경로계획)

  • 전재현;박민규;이민철
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.256-256
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    • 2000
  • In this parer, we present a real-time path planning algorithm which is integrated the artificial potential field(APF) and simulated annealing(SA) methods for mobile robot. The APF method in path planning has gained popularity since 1990's. It doesn't need the modeling of the complex configuration space of robot, and is easy to apply the path planning with simple computation. However, there is a major problem with APF method. It is the formation of local minima that can trap the robot before reaching its goal. So, to provide local minima recovery, we apply the SA method. The effectiveness of the proposed algorithm is verified through simulation.

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Makespan Minimization Problem for A Job - Multiple Machines Using Simulated Annealing (Simulated Annealing을 이용한 한 작업-다중 기계문제에서의 Makespan 최소화)

  • 이동주;황인극;김진호
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.5 no.2
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    • pp.137-140
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    • 2004
  • 다중 프로세서 시스템이 개발됨에 따라, 새로운 일정계획문제, 하나의 작업이 하나이상의 기계에 의해 동시에 처리되어야 하는 문제가 대두되었다. 이 연구에서는 선행관계를 가진 이러한 다중 프로세서 일정계획문제에 대해 다루어 보았다. 이 연구의 목적은 makespan을 최소화하는 일정계획을 찾는 것이다. 일반적으로 Branch and Bound 기법을 이용하여 선행관계를 가진 다중 프로세서 일정계획문제의 최적해를 찾았는데, 해의 탐색시간이 너무 오래 걸린다는 단점이 있었다. 본 연구에서는 짧은 시간 내에 최적해와 가까운 근사해를 simulated annealing(SA)방법을 이용하여 구해보았다. SA의 성능을 측정하기 위하여, SA의 CPU 처리시간과 구한 근사해를 40개의 예제문제를 통하여 Kramer의 방법의 CPU 처리시간과 최적해와 비교해 보았다.

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An Enhanced Simulated Annealing Algorithm for the Set Covering Problem (Set Covering 문제의 해법을 위한 개선된 Simulated Annealing 알고리즘)

  • Lee, Hyun-Nam;Han, Chi-Geun
    • IE interfaces
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    • v.12 no.1
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    • pp.94-101
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    • 1999
  • The set covering(SC) problem is the problem of covering all the rows of an $m{\times}n$ matrix of ones and zeros by a subset of columns with a minimal cost. It has many practical applications of modeling of real world problems. The SC problem has been proven to be NP-complete and many algorithms have been presented to solve the SC problem. In this paper we present hybrid simulated annealing(HSA) algorithm based on the Simulated Annealing(SA) for the SC problem. The HSA is an algorithm which combines SA with a crossover operation in a genetic algorithm and a local search method. Our experimental results show that the HSA obtains better results than SA does.

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A Robust Design of Simulated Annealing Approach : Mixed-Model Sequencing Problem (시뮬레이티드 어닐링 알고리듬의 강건설계 : 혼합모델 투입순서 결정문제에 대한 적용)

  • Kim, Ho-Gyun;Paik, Chun-Hyun;Cho, Hyung-Soo
    • IE interfaces
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    • v.15 no.2
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    • pp.189-198
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    • 2002
  • Simulated Annealing(SA) approach has been successfully applied to the combinatorial optimization problems with NP-hard complexity. To apply an SA algorithm to specific problems, generic parameters as well as problem-specific parameters must be determined. To overcome the embedded nature of SA, long computational time, some studies suggested the parameter design methods of determining SA related parameters. In this study, we propose a new parameter design approach based on robust design method. To show the effectiveness of the proposed method, the extensive computation experiments are conducted on the mixed-model sequencing problems.

Acceleration of Simulated Annealing and Its Application for Virtual Path Management in ATM Networks (Simulated Annealing의 가속화와 ATM 망에서의 가상경로 설정에의 적용)

  • 윤복식;조계연
    • Journal of the Korean Operations Research and Management Science Society
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    • v.21 no.2
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    • pp.125-140
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    • 1996
  • Simulated annealing (SA) is a very promising general purpose algorithm which can be conveniently utilized for various complicated combinatorial optimization problems. But its slowness has been pointed as a major drawback. In this paper, we propose an accelerated SA and test its performance experimentally by applying it for two standard combinatorial optimization problems (TSP(Travelling Salesman Problem) and GPP(Graph Partitioning Problem) of various sizes. It turns out that performance of the proposed method is consistently better both in convergenge speed and the quality of solution than the conventional SA or SE (Stochastic Evolution). In the second part of the paper we apply the accelerated SA to solve the virtual path management problem encountered in ATM netowrks. The problem is modeled as a combinatorial optimization problem to optimize the utilizy of links and an efficient SA implementation scheme is proposed. Two application examples are given to demonstrate the validity of the proposed algorithm.

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Modified Simulated Annealing Algorithms for Optimal Seismic Design of Braced Frame Struvtures (2차원 가새골조의 최적내진설계를 위한 MSA 알고리즘)

  • Lee, Sang Kwan;Seong, Chang Won;Park, Hyo Seon
    • Journal of Korean Society of Steel Construction
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    • v.12 no.6
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    • pp.629-638
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    • 2000
  • With the positive features of simulated annealing algorithms such as simplicity of the algorithm and the possibility of finding global optimum solution, SA algorithm has been widely applied to structural optimization problems. However, the algorithms are far from practical applications in structural design or optimization of building structures due to requirement of a large number of iterations and dependency on cooling schedule and stopping criteria. In this paper, with the modification of annealing process and stopping criteria, a MSA algorithm is presented in the form of two phase annealing process for optimal seismic design of braced structures. The performance of the proposed algorithm has been illustrated in detail.

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An enhanced simulated annealing algorithm for topology optimization of steel double-layer grid structures

  • Mostafa Mashayekhi;Hamzeh Ghasemi
    • Advances in Computational Design
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    • v.9 no.2
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    • pp.115-136
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    • 2024
  • Stochastic optimization methods have been extensively studied for structural optimization in recent decades. In this study, a novel algorithm named the CA-SA method, is proposed for topology optimization of steel double-layer grid structures. The CA-SA method is a hybridized algorithm combining the Simulated Annealing (SA) algorithm and the Cellular Automata (CA) method. In the CA-SA method, during the initial iterations of the SA algorithm, some of the preliminary designs obtained by SA are placed in the cells of the CA. In each successive iteration, a cell is randomly chosen from the CA. Then, the "local leader" (LL) is determined by selecting the best design from the chosen cell and its neighboring ones. This LL then serves as the leader for modifying the SA algorithm. To evaluate the performance of the proposed CA-SA algorithm, two square-on-square steel double-layer grid structures are considered, with discrete cross-sectional areas. These numerical examples demonstrate the superiority of the CA-SA method over SA, and other meta-heuristic algorithms reported in the literature in the topology optimization of large-scale skeletal structures.

Synthesis of binary phase computer generated hologram by usngin an efficient simulated annealing algorithm (효율적인 Simulated Annealing 알고리듬을 이용한 이진 위상 컴퓨터형성 홀로그램의 합성)

  • 김철수;김동호;김정우;배장근;이재곤;김수중
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.32A no.2
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    • pp.111-119
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    • 1995
  • In this paper, we propose an efficient SA(simulated annealing) algorithm for the synthesis of binary phase computer generated hologram. SA algorithm is a method to find the optimal solution through iterative technique. It is important that selecting cost function and parameters within this algorithm. The aplications of converentional SA algorithm to synthesize parameters within this algorithm. The applications of conventional SA algorithm to synthesize binary hologram have many problems because of inappropriate paramters and cost function. So, we propose a new cost function and a calculation technique of proper parameters required to achieve the optimal solution. Computer simulation results show that the proposed method is better than conventional method in terms of diffraction efficiency and reconstruction error. Also, we show the reconstructed images by the proposed method through optical esperiment.

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