• 제목/요약/키워드: simulated annealing method

검색결과 301건 처리시간 0.028초

Real Protein Prediction in an Off-Lattice BLN Model via Annealing Contour Monte Carlo

  • Cheon, Soo-Young
    • 응용통계연구
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    • 제22권3호
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    • pp.627-634
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    • 2009
  • Recently, the general contour Monte Carlo has been proposed by Liang (2004) as a space annealing version(ACMC) for optimization problems. The algorithm can be applied successfully to determine the ground configurations for the prediction of protein folding. In this approach, we use the distances between the consecutive $C_{\alpha}$ atoms along the peptide chain and the mapping sequences between the 20-letter amino acids and a coarse-grained three-letter code. The algorithm was tested on the real proteins. The comparison showed that the algorithm made a significant improvement over the simulated annealing(SA) and the Metropolis Monte Carlo method in determining the ground configurations.

Cauchy와 Gaussian 확률 분포를 이용한 Simulated Annealing 알고리즘 (Simulated Annealing Algorithm Using Cauchy-Gaussian Probability Distributions)

  • 이동주;이창용
    • 산업경영시스템학회지
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    • 제33권3호
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    • pp.130-136
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    • 2010
  • In this study, we propose a new method for generating candidate solutions based on both the Cauchy and the Gaussian probability distributions in order to use the merit of the solutions generated by these distributions. The Cauchy probability distribution has larger probability in the tail region than the Gaussian distribution. Thus, the Cauchy distribution can yield higher probabilities of generating candidate solutions of large-varied variables, which in turn has an advantage of searching wider area of variable space. On the contrary, the Gaussian distribution can yield higher probabilities of generating candidate solutions of small-varied variables, which in turn has an advantage of searching deeply smaller area of variable space. In order to compare and analyze the performance of the proposed method against the conventional method, we carried out experiments using benchmarking problems of real valued functions. From the result of the experiment, we found that the proposed method based on the Cauchy and the Gaussian distributions outperformed the conventional one for most of benchmarking problems, and verified its superiority by the statistical hypothesis test.

Development of a novel reconstruction method for two-phase flow CT with improved simulated annealing algorithm

  • Yan, Mingfei;Hu, Huasi;Hu, Guang;Liu, Bin;He, Chao;Yi, Qiang
    • Nuclear Engineering and Technology
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    • 제53권4호
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    • pp.1304-1310
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    • 2021
  • Two-phase flow, especially gas-liquid two-phase flow, has a wide application in industrial field. The diagnosis of two-phase flow parameters, which directly determine the flow and heat transfer characteristics, plays an important role in providing the design reference and ensuring the security of online operation of two-phase flow system. Computer tomography (CT) is a good way to diagnose such parameters with imaging method. This paper has proposed a novel image reconstruction method for thermal neutron CT of two-phase flow with improved simulated annealing (ISA) algorithm, which makes full use of the prior information of two-phase flow and the advantage of stochastic searching algorithm. The reconstruction results demonstrate that its reconstruction accuracy is much higher than that of the reconstruction algorithm based on weighted total difference minimization with soft-threshold filtering (WTDM-STF). The proposed method can also be applied to other types of two-phase flow CT modalities (such as X(𝛄)-ray, capacitance, resistance and ultrasound).

A modified simulated annealing search algorithm for scheduling of chemical batch processes with CIS policy

  • Kim, Hyung-Joon;Jung, Jae-Hak
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1995년도 Proceedings of the Korea Automation Control Conference, 10th (KACC); Seoul, Korea; 23-25 Oct. 1995
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    • pp.319-322
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    • 1995
  • As a trend toward multi-product batch processes is increasing in Chemical Process Industry (CPI), multi-product batch scheduling has been actively studied. But the optimal production scheduling problems for multi-product batch processes are known as NP-complete. Recently Ku and Karimi [5] have studied Simulated Annealing(SA) and Jung et al.[6] have developed Modified Simulated Annealing (MSA) method which was composed of two stage search algorithms for scheduling of batch processes with UIS and NIS. Jung et al.[9] also have studied the Common Intermediate Storage(CIS) policy which have accepted as a high efficient intermediate storage policy. It can be also applied to pipeless mobile intermediate storage pacilities. In spite of these above researches, there have been no contribution of scheduling of CIS policy for chemical batch processes. In this paper, we have developed another MSA for scheduling chemical batch processes with searching the suitable control parameters for CIS policy and have tested the this algorithm with randomly generated various scheduling problems. From these tests, MSA is outperformed to general SA for CIS batch process system.

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이웃해 탐색 기법을 이용한 Maximal Covering 문제의 해결 (Neighborhood Search Algorithms for the Maximal Covering Problem)

  • 황준하
    • 한국컴퓨터정보학회논문지
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    • 제11권1호
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    • pp.129-138
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    • 2006
  • 지금까지 maximal covering문제를 해결하기 위해 다양한 기법들이 적용되어 왔다. 타부 탐색 역시 그 중의 하나이다. 그러나 기존 연구에서는 타부 탐색을 비롯한 언덕오르기 탐색이나 시뮬레이티드 어닐링과 같은 이웃해 탐색 기법들에 대한 종합적인 분석과 성능 향상을 위한 노력이 부족하였다. 본 논문에서는 다양한 실험과 분석을 통해 이웃해 탐색 기법들의 성능을 향상시키기 위한 방안을 소개한다. 기본적으로 모든 이웃해 탐색 기법들은 k-exchange 이웃해 생성 방법을 사용하고 있으며 다양한 파라미터 설정에 따라 각 기법의 성능이 어떻게 달라지는가를 분석하였다. 실험 결과 단순 언덕오르기 탐색과 시뮬레이티드 어닐링이 다른 기법들에 비해 훨씬 우수한 탐색 성능을 보였으며, 일반적인 경우와는 달리 단순 언덕오르기 탐색이 시뮬레이티드 어닐링과 비슷한 성능을 보임을 확인하였다.

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Simulated Annealing 방법을 이용한 온라인 벡터 양자화기 설계 (On-line Vector Quantizer Design Using Simulated Annealing Method)

  • 송근배;이행세
    • 정보처리학회논문지B
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    • 제8B권4호
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    • pp.343-350
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    • 2001
  • 백터 양자화기 설계는 다차원의 목적함수를 최소화하는 학습 알고리즘을 필요로 한다. 일반화된 Lloyd 방법(GLA)은 벡터 양자화기 설계를 위해 오늘날 가장 널리 사용되는 알고리즘이다. GLA 는 일괄처리(batch) 방식으로 코드북을 생성하며 목적함수를 단조 감소시키는 강하법(descent algorithm)의 일종이다. 한편 Kohonen 학습법(KLA)은 학습벡터가 입력되는 동안 코드북이 갱신되는 온라인 벡터 양자화기 설계 알고리즘 이다. KLA는 원래 신경망 학습을 위해 Kohonen에 의해 제안되었다. KLA 역시 GLA와 마찬가지로 강하법의 일종이라 할 수 있다. 따라서 이들 두 알고리즘은, 비록 사용하기 편리하고 안정적으로 동작을 하지만, 극소(local minimum) 점으로 수렴하는 문제를 안고 있다. 우리는 이 문제와 관련하여 simulated annealing(SA) 방법의 응용을 논하고자 한다. SA는 현재까지 극소에 빠지지 않고 최소(global minimum)로 수렴하면서, 해의 수렴이 (통계적으로) 보장되는 유일한 방법이라 할 수 있다. 우리는 먼저 GLA에 SA를 응용한 그 동안의 연구를 개괄한다. 다음으로 온라인 방식의 벡터 양자화가 설계에 SA 방법을 응용함으로써 SA 방법에 기초한 새로운 온라인 학습 알고리즘을 제안한다. 우리는 이 알고리즘을 OLVQ-SA 알고리즘이라 부르기로 한다. 가우스-마코프 소스와 음성데이터에 대한 벡터양자화 실험 결과 제안된 방법이 KLA 보다 일관되게 우수한 코드북을 생성함을 보인다.

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능동방음벽 시스템의 제어 음원 위치 선정에 미치는 최적화 기법 성능에 관한 고찰 (A Study on the Performance of Optimization Techniques on the Selection of Control Source Positions in an Active Noise Barrier System)

  • 임형진;백광현
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 추계학술대회논문집
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    • pp.1012-1015
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    • 2004
  • There have been several kinds of attempts to actively control the deflected noise behind the noise barrier. Omoto's work in 1993 would be one of the fundamental studies, where he placed the control sources uniformly parallel to the noise barrier. Following this study, Yang pointed that the average distance between the noise source and control sources is more important than the arrangement of control sources such as a straight line or an arc type distribution. In 2004, Baek tried to show optimal arrangement of control sources while keeping the average distance between the noise source and control sources. He used simulated annealing algorithm which is one of the natural algorithms for the selections of optimal control source positions, but the searching technique was a hybrid of the simulated annealing and the sequential searching to adapt to the vast amount of searching time. This study is about the performance comparison between the pure sequential searching and the hybrid one. The simulation results show very similar performance and a pure simulated annealing searching will be more beneficial for the noise reduction performance but at the cost of computing time.

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Image Reconstruction using Simulated Annealing Algorithm in EIT

  • Kim Ho-Chan;Boo Chang-Jin;Lee Yoon-Joon
    • International Journal of Control, Automation, and Systems
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    • 제3권2호
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    • pp.211-216
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    • 2005
  • In electrical impedance tomography (EIT), various image reconstruction algorithms have been used in order to compute the internal resistivity distribution of the unknown object with its electric potential data at the boundary. Mathematically, the EIT image reconstruction algorithm is a nonlinear ill-posed inverse problem. This paper presents a simulated annealing technique as a statistical reconstruction algorithm for the solution of the static EIT inverse problem. Computer simulations with 32 channels synthetic data show that the spatial resolution of reconstructed images by the proposed scheme is improved as compared to that of the mNR algorithm at the expense of increased computational burden.

Simulated Annealing 알고리즘에 의한 위상격자를 이용한 실시간 광 영상 생성 (Real time optical image generation using phase grating with simulated annealing algorithm)

  • 김철수;김정우;배장근;김수중
    • 전자공학회논문지B
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    • 제33B권6호
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    • pp.149-155
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    • 1996
  • In this paper, we designed binary phase grating with SA (simulated annealing) algorithm for image generation, and used LCTV(liquid crystal television) as phase modulator. We generated optical image using LCTV which controlled by personal computer in real time. Many parameters in SA algorithm are determined by average deviation of the cost function, not experimental method. It was confirmed that the LCTV could be used as a phase modulator through mach-zehnder interferometering experiment. The various optical images are generated in real itme by fourier transforming of the phase gratings on LCTV which is controlled by personal computer and they can be used for optical interconnection in a neural network and addressing information in a volume hologram etc.

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시뮬레이티드 어닐링 알고리즘을 이용한 기어열의 최적 기어비 분할법 개발 (A New Method to Find the Best Gear Ratio Using the Simulated Annealing Algorithm)

  • 배인호;정태형
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2002년도 춘계학술대회 논문집
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    • pp.687-692
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    • 2002
  • This paper reviews the existing methods to divide the gear ratios of a multi-stage gear train, and proposes a simulated annealing-based algorithm to find the best gear ratios. The existing methods have their own limitations to be used in practical design, and are also problematic to be automated in a design system. However, the proposed algorithm is a general one which can be applied to gear trains having any number of stages, and offers a satisfactory result in a very short time. It is expected to be useful as a design sub-module of the design system for multi-stage gear drives.

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