• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2000년도 봄 학술발표회논문집
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• pp.458-465
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• 2000

In the field of structural optimization simulated annealing (SA) algorithm has widely been adopted as an optimizer with the positive features of SA such as simplicity of the algorithm and possibility of finding global solution However, annealing process of SA algorithm based on random generator with the zeroth order structural information requires a large of number of iterations highly depending on cooling schedules and stopping criteria. In this paper, MSA algorithm is presented in the form of two phase annealing process with the effective cooling schedule and stopping criteria. With the application to optimal seismic design of steel structures, the performance of the proposed MSA algorithm has been demonstrated with respect to stability and global convergence of the algorithm

• 대한전기학회논문지:전력기술부문A
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• 제53권8호
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• pp.477-483
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• 2004

In competitive electricity markets, maintenance schedule is submitted by generation companies (GENCOs) and transmission companies (TRANSCOs), and coordinated by Independent System Operator (ISO) with the adequacy criterion. This paper presents an alternative coordination procedure by ISO on the maintenance schedule. In this paper, it is focused on modeling a coordination algorithm by ISO for the maintenance schedule based on the Simulated Annealing algorithm. The proposed model employs the minimum information such as generator capacity, forced outage rate and generator maintenance schedules. The objective function of this model represents minimization of adjustment on schedules submitted by GENCOs.

• 동력기계공학회지
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• 제2권3호
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• pp.60-67
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• 1998

Edge detection is the first step and very important step in image analysis. We cast edge detection as a problem in cost minimization. This is achieved by the formulation of a cost function that evaluates the quality of edge configurations. The cost function can be used as a basis for comparing the performances of different detectors. This cost function is made of desirable characteristics of edges such as thickness, continuity, length, region dissimilarity. And we use a simulated annealing algorithm for minimum of cost function. Simulated annealing are a class of adaptive search techniques that have been intensively studied in recent years. We present five strategies for generating candidate states. Experimental results(building image and test image) which verify the usefulness of our simulated annealing approach to edge detection are better than other operator.

• 한국컴퓨터정보학회논문지
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• 제6권1호
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• pp.25-30
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• 2001

본 논문에서는 Rural Postman Problem(RPP) 해법을 위한 향상된 Simulated Annealing(SA) 알고리즘을 제안한다. SA 알고리즘에서는 냉각 스케줄을 어떻게 설정하느냐에 따라 알고리즘의 성능에 영향을 준다. 따라서, 본 논문에서는 RPP를 위한 냉각 스케줄을 제안하고, 기존에 많이 적용되는 냉각스케줄을 적용한 결과와 비교하여 SA 알고리즘의 성능을 분석한다 실험 결과에서는 본 논문에서 제안한 알고리즘이 기존의 SA 알고리즘에 비해 문제의 크기가 클수록 좋은 결과를 얻는다는 것을 알 수 있었다.

• 산업공학
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• 제15권4호
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• pp.338-348
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• 2002

In this paper, we present a restricted tabu search(RTS) algorithm that schedules jobs on identical parallel machines in order to minimize the maximum lateness of jobs. Jobs have release times and due dates. Also, sequence-dependent setup times exist between jobs. The RTS algorithm consists of two main parts. The first part is the MATCS(Modified Apparent Tardiness Cost with Setups) rule that provides an efficient initial schedule for the RTS. The second part is a search heuristic that employs a restricted neighborhood generation scheme with the elimination of non-efficient job moves in finding the best neighborhood schedule. The search heuristic reduces the tabu search effort greatly while obtaining the final schedules of good quality. The experimental results show that the proposed algorithm gives better solutions quickly than the existing heuristic algorithms such as the RHP(Rolling Horizon Procedure) heuristic, the basic tabu search, and simulated annealing.

• 한국항공우주학회지
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• 제32권6호
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• pp.49-55
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• 2004

컴퓨터 성능의 향상으로 통계학적 최적화기법이 구조설계최적화에 시도되고 있다. 통계학적 최적화 가법 중 시뮬레이티드 애닐링 기법도 구조 최적화 분야에 적용되기 시작하였다. 시뮬레이티드 애닐링, 불쯔만 애닐링, 패스트 애닐링, 어댑티브 시뮬레이티드 애닐링을 적용하여, 트러스 구조물의 최적화에 적용시켜 목적함수를 향상시키고 함수계산량을 감소시키도록 하였다. 특히 알고리즘 중에서 수렴성과 목적함수의 우수성을 구현하기 위하여 어댑티브 시뮬레이티드 애닐링의 냉각스케줄의 냉각변수를 다양하게 적용하여 트러스 구조물을 최적화하였다. 또한 볼쯔만 애닐링과 어댑티브 시뮬레이티드 애닐링을 복합한 냉각스캐줄로 10부재와 25부재 트러스 구조물의 최적화도 수행하여 보았다.

• 산업공학
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• 제16권2호
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• pp.201-210
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• 2003

The purpose of this research is to develop a scheduling system for CAL (Continuous Annealing Line) in Cold Rolling Mill. Based on CSP (Constraint Satisfaction Problem) technique in artificial intelligence, appropriate algorithms to provide schedules satisfying all the constraints imposed on CAL are designed and developed. Performance tests show that the proposed scheduling system outperforms human operators in case of aggregating the same attributes and minimizing the thickness differences between two adjacent coils.

• Journal of Electrical Engineering and Technology
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• 제6권4호
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• pp.431-438
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• 2011

To ensure that equipment outages do not directly impact the reliability of the ISO-controlled grid, market participants request permission and receive approval for planned outages from the independent system operator (ISO) in competitive electricity markets. In the face of major generation outages, the ISO will make a critical decision as regards the scheduling of the essential maintenance for myriads of generating units over a fixed planning horizon in accordance with security and adequacy assessments. Mainly, we are concerned with a fundamental framework for ISO's maintenance coordination in order to determine precedence of conflicting outages. Simulated annealing, a powerful, general-purpose optimization methodology suitable for real combinatorial search problems, is used. Generally, the ISO will put forward its best effort to adjust individual generator maintenance schedules according to the time preferences of each power generator (GENCO) by taking advantage of several factors such as installed capacity and relative weightings assigned to the GENCOs. Thus, computer testing on a four-GENCO model is conducted to demonstrate the effectiveness of the proposed method and the applicability of the solution scheme to large-scale maintenance scheduling coordination problems.

• 한국초전도ㆍ저온공학회논문지
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• 제6권1호
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• pp.1-5
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• 2004

Long length of Bi-2223/Ag superconducting wives were fabricated by stacking and drawing process with advanced heat-treatment schedules. Intermediate annealing was carried out to increase the homogeneity and uniformity of the superconducting filaments embedded in the silver matrix. Phase modification from tetragonal to orthorhombic Bi-2212 by pre heat treatment(PHT) was executed to improve the texture and phase transformation of Bi-2223. Drawing stress was measured to predict the sausaging and stress limit. Rolling Parameters such as thickness. width and winding tension were investigated to roll the tape with uniformity. 1 km length of Bi-2223/Ag superconducting wires were fabricated without any breakage. Critical current (Je) of 270 m length of superconducting tapes was measured over than $70 A/cm^2$ continuously after final sintering.

• JSTS:Journal of Semiconductor Technology and Science
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• 제9권1호
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• pp.29-36
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• 2009

Power supply noise is fundamentally caused by large current peaks. Since large current peaks are induced by simultaneous switching of many circuit elements, power supply noise can be minimized by deliberate clock scheduling which utilizes nonzero clock skew. In this paper, nonzero skew clock scheduling is used to avoid the large peak current and consequently reduce power supply noise. While previous approaches require extra characterization efforts to acquire current waveform of a circuit, we approximate it only with existing cell library information to be easily adapted to conventional design flow. A simulated annealing based algorithm is performed, and the peak current values are estimated for feasible clock schedules found by the algorithm. The clock schedule with the minimum peak current is selected for a solution. Experimental results on ISCAS89 benchmark circuits show that the proposed method can effectively reduce the peak current.