• Title/Summary/Keyword: Heuristic search

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A Novel Binary Ant Colony Optimization: Application to the Unit Commitment Problem of Power Systems

  • Jang, Se-Hwan;Roh, Jae-Hyung;Kim, Wook;Sherpa, Tenzi;Kim, Jin-Ho;Park, Jong-Bae
    • Journal of Electrical Engineering and Technology
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    • v.6 no.2
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    • pp.174-181
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    • 2011
  • This paper proposes a novel binary ant colony optimization (NBACO) method. The proposed NBACO is based on the concept and principles of ant colony optimization (ACO), and developed to solve the binary and combinatorial optimization problems. The concept of conventional ACO is similar to Heuristic Dynamic Programming. Thereby ACO has the merit that it can consider all possible solution sets, but also has the demerit that it may need a big memory space and a long execution time to solve a large problem. To reduce this demerit, the NBACO adopts the state probability matrix and the pheromone intensity matrix. And the NBACO presents new updating rule for local and global search. The proposed NBACO is applied to test power systems of up to 100-unit along with 24-hour load demands.

Solution Methods for Reliability Optimization of a Series System with Component Choices (부품선택이 존재하는 직렬시스템의 신뢰성 최적화 해법)

  • Kim, Ho-Gyun;Bae, Chang-Ok;Kim, Jae-Hwan;Son, Joo-Young
    • Journal of Korean Institute of Industrial Engineers
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    • v.34 no.1
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    • pp.49-56
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    • 2008
  • Reliability has been considered as an important design measure in various industrial systems. We discuss a reliability optimization problem with component choices (ROP-CC) subject to a budget constraint. This problem has been known as a NP-hard problem in the reliability design fields. Several researchers have been working to find the optimal solution through different heuristic methods. In this paper, we describe our development of simulated annealing (SA) and tabu search (TS) algorithms and a reoptimization procedure of the two algorithms for solving the problem. Experimental results for some examples are shown to evaluate the performance of these methods. We compare the results with the solutions of a previous study which used ant system (AS) and the global optimal solution of each example obtained through an optimization package, CPLEX 9.1. The computational results indicate that the developed algorithms outperform the previous results.

Adaptive Clustering Algorithm for Recycling Cell Formation An Application of the Modified Fuzzy ART Neural Network

  • Park, Ji-Hyung;Seo, Kwang-Kyu
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 1999.03a
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    • pp.253-260
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    • 1999
  • The recycling cell formation problem means that disposal products are classified into recycling part families using group technology in their end of life phase. Disposal products have the uncertainties of product status by usage influences during product use phase and recycling cells are formed design, process and usage attributes. In order to treat the uncertainties, fuzzy set theory and fuzzy logic-based neural network model are applied to recycling cell formation problem for disposal products. In this paper, a heuristic approach for fuzzy ART neural network is suggested. The modified Fuzzy ART neural network is shown that it has a great efficiency and give an extension for systematically generating alternative solutions in the recycling cell formation problem. We present the results of this approach applied to disposal refrigerators and the comparison of performances between other algorithms. This paper introduced a procedure which integrates economic and environmental factors into the disassembly of disposal products for recycling in recycling cells. A qualitative method of disassembly analysis is developed and its aim is to improve the efficiency of the disassembly and to generated an optimal disassembly which maximize profits and minimize environmental impact. Three criteria established to reduce the search space and facilitate recycling opportunities.

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Optimal and Approximate Solutions of Object Functions for Base Station Location Problem (기지국 위치 문제를 위한 목적함수의 최적해 및 근사해)

  • Sohn, Surg-Won
    • The KIPS Transactions:PartC
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    • v.14C no.2
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    • pp.179-184
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    • 2007
  • The problem of selecting base station location in the design of mobile communication system has been basically regarded as a problem of assigning maximum users in the cell to the minimum base stations while maintaining minimum SIR. and it is NP hard. The objective function of warehouse location problem, which has been used by many researchers, is not proper function in the base station location problem in CDMA mobile communication, The optimal and approximate solutions have been presented by using proposed object function and algorithms of exact solution, and the simulation results have been assessed and analyzed. The optimal and approximate solutions are found by using mixed integer programming instead of meta-heuristic search methods.

Cost-based Optimization of Composite Web Service Executions Using Intensional Results (내포 결과를 이용한 복합 웹 서비스 실행의 비용 기반 최적화)

  • Park, Chang-Sup
    • Journal of KIISE:Databases
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    • v.33 no.7
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    • pp.715-726
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    • 2006
  • Web service technologies provide a standard means for interoperation and integration of heterogeneous applications distributed over the Internet. For efficient execution of hierarchically interacting composite web services, this paper proposes an approach to distribute web service invocations over peer systems effectively, exploiting intensional XML data embedding external service calls as a result of well services. A cost-based optimization problem on the execution of web services using intensional results was formalized, and a heuristic search method to find an optimal solution and a greedy algorithm to generate an efficient invocation plan quickly were suggested in this paper. Experimental evaluation shows that the proposed greedy algorithm provides near-optimal solutions in an acceptable time even for a large number of Web services.

Topology, shape, and size optimization of truss structures using modified teaching-learning based optimization

  • Tejani, Ghanshyam G.;Savsani, Vimal J.;Patel, Vivek K.;Bureerat, Sujin
    • Advances in Computational Design
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    • v.2 no.4
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    • pp.313-331
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    • 2017
  • In this study, teaching-learning based optimization (TLBO) is improved by incorporating model of multiple teachers, adaptive teaching factor, self-motivated learning, and learning through tutorial. Modified TLBO (MTLBO) is applied for simultaneous topology, shape, and size optimization of space and planar trusses to study its effectiveness. All the benchmark problems are subjected to stress, displacement, and kinematic stability constraints while design variables are discrete and continuous. Analyses of unacceptable and singular topologies are prohibited by seeing element connectivity through Grubler's criterion and the positive definiteness. Performance of MTLBO is compared to TLBO and state-of-the-art algorithms available in literature, such as a genetic algorithm (GA), improved GA, force method and GA, ant colony optimization, adaptive multi-population differential evolution, a firefly algorithm, group search optimization (GSO), improved GSO, and intelligent garbage can decision-making model evolution algorithm. It is observed that MTLBO has performed better or found nearly the same optimum solutions.

Development of an Educational Simulator of Particle Swarm Optimization: Application to Economic Dispatch Problems (교육용 PSO 시뮬레이터의 개발: 경제급전에의 적용)

  • Lee, Woo-Nam;Jeong, Yun-Won;Lee, Joo-Won;Park, Jong-Bae;Shin, Joong-Rin
    • Proceedings of the KIEE Conference
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    • 2006.11a
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    • pp.198-200
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    • 2006
  • This paper presents a development of an educational simulator of particle swarm optimization (PSO) and application for solving the test functions and economic dispatch (ED) problems with nonsmooth cost functions. A particle swarm optimization is one of the most powerful methods for solving global optimization problems. It is a population-based search algorithm and searches in parallel using a group of particles similar to other AI-based heuristic optimization techniques. In developed simulator, lecturers and students can select the functions for simulation and set the parameters that have an influence on PSO performance. To improve searching capability for ED problems, a crossover operation is proposed to the position update of each individual (CR-PSO). To verify the feasibility of CR-PSO method, numerical studies have been performed for two different sample systems. The proposed CR-PSO method outperforms other algorithms in solving ED problems.

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Task Scheduling and Multiple Operation Analysis of Multi-Function Radars (다기능 레이더의 임무 스케줄링 및 복수 운용 개념 분석)

  • Jeong, Sun-Jo;Jang, Dae-Sung;Choi, Han-Lim;Yang, Jae-Hoon
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.42 no.3
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    • pp.254-262
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    • 2014
  • Radar task scheduling deals with the assignment of task to efficiently enhance the radar performance on the limited resource environment. In this paper, total weighted tardiness is adopted as the objective function of task scheduling in operation of multiple multi-function radars. To take into account real-time implementability, heuristic index-based methods are presented and investigated. Numerical simulations for generic search and track scenarios are performed to evaluate the proposed methods, in particular investigating the effectiveness of multi-radar operation concepts.

Path Planning of Autonomous Guided Vehicle Using fuzzy Control & Genetic Algorithm (유전자 알고리즘과 퍼지 제어를 적용한 자율운송장치의 경로 계획)

  • Kim, Yong-Gug;Lee, Yun-Bae
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.4 no.2
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    • pp.397-406
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    • 2000
  • Genetic algorithm is used as a means of search, optimization md machine learning, its structure is simple but it is applied to various areas. And it is about an active and effective controller which can flexibly prepare for changeable circumstances. For this study, research about an action base system evolving by itself is also being considered. There is to have a problem that depended entirely on heuristic knowledge of expert forming membership function and control rule for fuzzy controller design. In this paper, for forming the fuzzy control to perform self-organization, we tuned the membership function to the most optimal using a genetic algorithm(GA) and improved the control efficiency by the self-correction and generation of control rules.

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A Ring-Mesh Topology Optimization in Designing the Optical Internet (생존성을 보장하는 링-그물 구조를 가진 광 인터넷 WDM 망 최적 설계)

  • 이영호;박보영;박노익;이순석;김영부;조기성
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.4B
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    • pp.455-463
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    • 2004
  • In this paper, we deal with a ring-mesh network design problem arising from the deployment of WDM for the optical internet. The ring-mesh network consists of ring topology and full mesh topology for satisfying traffic demand while minimizing the cost of OAOMs and OXCs. The problem seeks to find an optimal clustering of traffic demands in the network such that the total number of node assignments is minimized, while satisfying ring capacity and node cardinality constraints. We formulate the problem as a mixed-integer programming model and prescribe a tabu search heuristic procedure Promising computational results within 3% optimality gap are obtained using the proposed method.