• 제목/요약/키워드: Simulated-Annealing

검색결과 634건 처리시간 0.037초

시뮬레이티드 어닐링을 이용한 배전계통 선로 재구성에 관한 연구 (A Study on Distribution System Reconfiguration using Simulated Annealing)

  • 전영재;최승규;이승윤;김재철
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 C
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    • pp.1085-1087
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    • 1998
  • A distribution systems loss minimum reconfiguration method by simulated annealing is proposed. The problem is a complex mixed integer programming problem and is very difficult to solve by a mathematical programming approach. Simulated annealing generates feasible solutions randomly and moves among these solutions using a strategy leading to a global minimum with high probabilities. The solution algorithm has been implemented in developed software package and tested on 32-bus system.

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A New Hybrid Genetic Algorithm for Nonlinear Channel Blind Equalization

  • Han, Soowhan;Lee, Imgeun;Han, Changwook
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제4권3호
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    • pp.259-265
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    • 2004
  • In this study, a hybrid genetic algorithm merged with simulated annealing is presented to solve nonlinear channel blind equalization problems. The equalization of nonlinear channels is more complicated one, but it is of more practical use in real world environments. The proposed hybrid genetic algorithm with simulated annealing is used to estimate the output states of nonlinear channel, based on the Bayesian likelihood fitness function, instead of the channel parameters. By using the desired channel states derived from these estimated output states of the nonlinear channel, the Bayesian equalizer is implemented to reconstruct transmitted symbols. In the simulations, binary signals are generated at random with Gaussian noise. The performance of the proposed method is compared with those of a conventional genetic algorithm(GA) and a simplex GA. In particular, we observe a relatively high accuracy and fast convergence of the method.

Reduction of Reconstruction Errors in Kinoform CGHs by Modified Simulated Annealing Algorithm

  • Yang, Han-Jin;Cho, Jeong-Sik;Won, Yong-Hyub
    • Journal of the Optical Society of Korea
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    • 제13권1호
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    • pp.92-97
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    • 2009
  • In this paper, a conventional simulated annealing (SA) method for optimization of a kinoform computer generated hologram (CGH) is analyzed and the SA method is modified to reduce a reconstruction error rate (ER) of the CGH. The dependences of the quantization level of the hologram pattern and the size of the data on the ER are analyzed. To overcome saturation of the ER, the conventional SA method is modified as it magnifies a Fourier-transformed pattern in the intermediate step. The proposed method can achieve a small ER less than 1%, which is impossible in the conventional SA method.

Simulated Annealing기법을 이용한 초음파의 계면 반사 특성평가 (Evaluation of ultrasonic reflection characteristics on an interface surface using Simulated Annealing)

  • 은길수;김노유;나환선
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2002년도 봄 학술발표회 논문집
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    • pp.395-400
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    • 2002
  • Epoxy coating and sealing used in nuclear plants for the protection of radiation degrades with aging and hazardous atmosphere. In order to evaluate the degradation of the epoxy, dependence of the acoustic impedance on the change of mechanical properties has been used. Unlike metals, the surface of the epoxy coating on a concrete liner is so wavy that the acoustic impedance is difficult to measure by using the reflectivity of the ultrasound on the interface surface because of the irregular reflection and propagation from the epoxy surface. SA(simulated annealing) algorithm is applied to calculate the acoustic impedance using a reflection wave from the rough epoxy surface. The surface waviness and acoustic impedance are taken into account and determined by SA method to evaluate the state of degradation quantitatively.

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구조물 최적설계를 위한 메타휴리스틱 알고리즘의 비교 연구 (An Comparative Study of Metaheuristic Algorithms for the Optimum Design of Structures)

  • 류연선;조현만
    • 수산해양교육연구
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    • 제29권2호
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    • pp.544-551
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    • 2017
  • Metaheuristic algorithms are efficient techniques for a class of mathematical optimization problems without having to deeply adapt to the inherent nature of each problem. They are very useful for structural design optimization in which the cost of gradient computation can be very expensive. Among them, the characteristics of simulated annealing and genetic algorithms are briefly discussed. In Metropolis genetic algorithm, favorable features of Metropolis criterion in simulated annealing are incorporated in the reproduction operations of simple genetic algorithm. Numerical examples of structural design optimization are presented. The example structures are truss, breakwater and steel box girder bridge. From the theoretical evaluation and numerical experience, performance and applicability of metaheuristic algorithms for structural design optimization are discussed.

베전 계통의 손실 최소화를 위한 시뮬레이티드 어닐링과 타부 탐색의 적용 (Application of Simulated Annealing and Tabu Search for Loss Minimization in Distribution Systems)

  • 전영재;김재철
    • 대한전기학회논문지:전력기술부문A
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    • 제50권1호
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    • pp.28-37
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    • 2001
  • This paper presents an efficient algorithm for the loss minimization of distribution system by automatic sectionalizing switch operation in large scale distribution systems. Simulated annealing is particularly well suited for large combinational optimization problem, but the use of this algorithm is also responsible for an excessive computation time requirement. Tabu search attempts to determine a better solution in the manner of a greatest-descent algorithm, but it can not give any guarantee for the convergence property. The hybrid algorithm of two methods with two tabu lists and the proposed perturbation mechanism is applied to improve the computation time and convergence property Numerical examples demonstrate the validity and effectiveness of the proposed methodology using a KEPCO's distribution system.

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Cold-formed steel channel columns optimization with simulated annealing method

  • Kripka, Moacir;Chamberlain Pravia, Zacarias Martin
    • Structural Engineering and Mechanics
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    • 제48권3호
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    • pp.383-394
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    • 2013
  • Cold-formed profiles have been largely used in the building industry because they can be easily produced and because they allow for a wide range of sections and thus can be utilized to meet different project requirements. Attainment of maximum performance by structural elements with low use of material is a challenge for engineering projects. This paper presents a numerical study aimed at minimizing the weight of lipped and unlipped cold-formed channel columns, following the AISI 2007 specification. Flexural, torsional and torsional-flexural buckling of columns was considered as constraints. The simulated annealing method was used for optimization. Several numerical simulations are presented and discussed to validate the proposal, in addition to an experimental example that qualifies its implementation. The ratios between lips, web width, and flange width are analyzed. Finally, it may be concluded that the optimization process yields excellent results in terms of cross-sectional area reduction.

시뮬레이티드 어닐링을 이용한 전기임픽던스단층촬영법의 영상복원 (A Image Reconstruction Uing Simulated Annealing in Electrical Impedance Tomograghy)

  • 김호찬;부창진;이윤준
    • 대한전기학회논문지:시스템및제어부문D
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    • 제52권2호
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    • pp.120-127
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    • 2003
  • 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 the 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 or genetic algorithm at the expense of increased computational burden.

정규화 기반 Adaptive Simulated Annealing을 이용한 마이크로어레이 데이터 분류 시스템 (The Classification System of Microarray Data Using Adaptive Simulated Annealing based on Normalization.)

  • 박수영;정채영
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2006년도 추계학술발표대회
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    • pp.69-72
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    • 2006
  • 최근 생명 정보학 기술의 발달로 마이크로 단위의 실험조작이 가능해짐에 따라 하나의 chip상에서 전체 genome의 expression pattern을 관찰할 수 있게 되었고, 동시에 수 만개의 유전자들 간의 상호작용도 연구가능하게 되었다. 이처럼 DNA 마이크로어레이 기술은 복잡한 생물체를 이해하는 새로운 방향을 제시해주게 되었다. 따라서 이러한 기술을 통해 얻어진 대량의 유전자 정보들을 효과적으로 분석하는 방법이 시급하다. 본 논문에서는 마이크로어레이 실험에서 다양한 원인에 의해 발생하는 잡음(noise)을 줄이거나 제거하는 과정인 정규화과정을 거쳐 특징 추출방법인 SVM(Support Vector Machine) 방법을 이용하여 데이터를 2개의 클래스로 나누고, 표준화 방법들의 성능 비교를 위해 Adaptive Simulated Annealing 알고리즘으로 정확도를 평가하는 분류 시스템을 설계 구현하였다.

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Hatch를 고려한 컨테이너 터미널 적재순서 최적화 연구 (A Study on the Optimization of Stowage Planning for Container Terminal Considered by Hatch)

  • 이상헌;김문규;안태호
    • 산업공학
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    • 제19권4호
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    • pp.270-280
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    • 2006
  • The shipping plan for an efficient augmentation of terminal is NP-hard problem which is subordinate to a shipping quantity. The load location problem and stowage planning problem are two important tactical problems for the efficient operations of container terminals. This paper is concerned with reduction of feasible region in constraints for stowage planning. After designing model which minimizes the number of shifting and the travel distance of the transfer crane, the simulated annealing algorithm is employed to search optimal solution quickly and accurately. In order to apply more realistic approach, the partial restriction through adding hatch is complemented to stowage planning decision problem applied in cluster. A variety of numerical experiments demonstrated that solutions by simulated annealing algorithm are useful and applicable in practice.