• 제목/요약/키워드: Precedence Operations

검색결과 41건 처리시간 0.022초

분해우선작업을 가지는 페트리 넷 기반의 분해순서계획모델 (A Petri Net based Disassembly Sequence Planning Model with Precedence Operations)

  • 서광규
    • 한국산학기술학회논문지
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    • 제9권5호
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    • pp.1392-1398
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    • 2008
  • 본 논문에서는 분해우선작업을 가지는 페트리 넷 기반의 분해순서계획모델을 제안한다. 모든 가능한 분해순서는 분해트리에 의해 생성되고, 분해우선순위와 분해가치 행렬을 이용하여 분해순서를 결정한다. 분해작업의 우선순위는 분해트리를 통하여 결정하고 분해작업의 가치는 제품의 마지막 수명단계의 경제적 분석에 의해 유도된다. 분해우선작업을 가지는 분해계획모델을 해결하기 위하여, 본 연구에서는 페트리 넷 기반의 휴리스틱 알고리듬을 개발한다. 개발된 알고리듬은 페트리 넷 모델의 전이순서에 기반을 두어 도달할 수 있는 모든 그래프의 노드를 탐색하여 최적의 혹은 근사최적의 분해순서를 생성한다. 본 연구에서는 냉장고를 대상으로 제안모델의 유효성을 입증한다.

이분할성 우선순위제약을 갖는 배낭문제에 대한 다면체적 절단평면 (Facets of Knapsack Polytopes with Bipartite Precedence Constraints)

  • 이경식;박성수;박경철
    • 한국경영과학회지
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    • 제23권4호
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    • pp.1-10
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    • 1998
  • We consider the precedence-constrained knapsack problem. which is a knapsack problem with precedence constraints imposed on the set of variables. Especially, we focus on the case where the precedence constraints cir be represented as a bipartite graph, which occurs most frequently in applications. Based on the previous studios for the general case, we specialize the polyhedral results on the related polytope and derive stronger results on the facet-defining properties of the inequalities.

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선후행 관계제약을 갖는 TSP 문제의 유전알고리즘 해법 (Traveling Salesman Problem with Precedence Relations based on Genetic Algorithm)

  • 문치웅;김규웅;김종수;허선
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 2000년도 춘계공동학술대회 논문집
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    • pp.48-51
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    • 2000
  • The traveling salesman problem with precedence relations (TSPPR) is harder than general traveling salesman problem. In this paper we propose an efficient genetic algorithm (GA) to solve the TSPPR. The key concept of the proposed genetic algorithm is a topological sort (TS). The results of numerical experiments show that the proposed GA approach produces an optimal solution for the TSPPR.

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Line balancing using a Hopfield network

  • Hashimoto, Yasunori;Nishikawa, Ikuko;Watanabe, Tohru;Tokumaru, Hidekatu
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국제학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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    • pp.391-394
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    • 1993
  • A new approach using a Hopfield type neural network to solve line balancing problems for manufacturing planning is proposed. The energy function of the network to evaluate solutions is composed of three terms;(a) an operation should be processed at one and only one workstation, (b) the precedence-relationship between two operations shoud be satisfied, and (c) the cycle-time of operations should be minimized. It is shown that the network can solve the line balancing problems but not always because of the difficulty to keep the precedence-relationship. Therefore, a method to keep the precedence-relationship by software logic is proposed and it is verified that the line-balancing prblems can be solved with high probability.

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Projections of Extended Formulations with precedence Variables for the Asymmetric Traveling Salesman Problem

  • Myung, Young-Soo
    • Management Science and Financial Engineering
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    • 제7권2호
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    • pp.1-11
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    • 2001
  • Gouveia and Pires (European Journal of Operations Research 112(1999) 134-146) have proposed four extended formulations having precedence variables as extra variables and characterized the projections of three of the four formulations into the natural variable space. In Gouveia and Pires (Discrete Applied Mathematics 112 (2001)), they also have introduced some other extended formulations with the same extra variables and conjectured that the projection of one of the proposed formulations is equivalent to the one proposed by Dantzig, Fulkerson, and Johnson (Operations Research 2(1954) 393-410). In this paper, we provide a unifying framework based on which we give alternative proofs on the projections of three extended formulations and new proofs on those of two formulations appeared in Gouveia and Pires(1999, 2001).

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서비스 전후 우선순위를 고려한 해군함정의 부두 할당에 관한 연구 (A Study on Berth Allocation for Navy Surface Vessel Considering Precedence Relationship among Services)

  • 정환식;김승권
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 2003년도 추계학술대회 및 정기총회
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    • pp.350-353
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    • 2003
  • Navy surface vessels require pier services such as emergency repair, oil supply, fm loading/unloading, crane, standby readiness, normal repair, gun arrangement, ammunition loading, and food loading during the period in port. The purpose of this study is to establish efficient berth allocation plan for navy surface vessels in home port under the limited resources of piers and equipments. The study suggests Mixed Integer Programing (MIP) model for bath allocation problem, considering precedence relationships among services. For a effective analysis, the model is implemented by ILOG OPL(Optimization Programming Language) Studio 3.1 and ILOG Cplex 7.0. The results of the model show reduction of berth shifts and increasement of service benefits. And thus, it would be a possibility of contribution in the improvement of fleet readiness.

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A resource-constrained job shop scheduling problem with general precedence constraints

  • Ahn, Jaekyoung
    • 경영과학
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    • 제10권1호
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    • pp.171-192
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    • 1993
  • In this paper, a rule for dispatching operations, named the Most Dissimilar Resources (MDR) dispatching rule is presented. The MDR dispatching rule has been designed to maximize utilization of resources in a resource-constrained job shop with general precedence constraints. In shown that solving the above scheduling problem with the MDR dispatching rule is equivalent to multiple solving of the maximum clique problem. A graph theoretic approach is used to model the latter problem. The pairwise counting heuristic of computational time complexity O(n$^{2}$) is developed to solve the maximum clique problem. An attempt is made to combine the MDR dispatching rule with the existing look-ahead dispatching rules. Computational experience indicates that the combined MDR dispatching rules provide solutions of better quality and consistency than the dispatching rules tested in a resource-constrained job shop.

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선행순서결정문제를 위한 Out-of-Kilter 해법의 적용과 부분순환로의 제거 (Elimination of Subtours Obtained by the Out-of-Kilter Algorithm for the Sequential Ordering Problem)

  • 권상호
    • 한국경영과학회지
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    • 제32권3호
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    • pp.47-61
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    • 2007
  • This paper presents two elimination methods of subtours, which is obtained by applying the Out-of-Kilter algorithm to the sequential ordering problem (SOP) to produce a feasible solution for the SOP. Since the SOP is a kind of asymmetric traveling salesman problem (ATSP) with precedence constraints, we can apply the Out-of-Kilter algorithm to the SOP by relaxing the precedence constraints. Instead of patching subtours, both of two elimination methods construct a feasible solution of the SOP by using arcs constructing the subtours, and they improve solution by running 3-opt and 4-opt at each iteration. We also use a perturbation method. cost relaxation to explore a global solution. Six cases from two elimination methods are presented and their experimental results are compared to each other. The proposed algorithm found 32 best known solutions out of the 34 instances from the TSPLIB in a reasonable time.

통합적인 공정순서와 가공기계 선정을 위한 유전 알고리즘 (Genetic Algorithm for Integrated Process Sequence and Machine Selection)

  • 문치웅;서윤호;이영해;최경현
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 2000년도 춘계공동학술대회 논문집
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    • pp.405-408
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    • 2000
  • The objective of this paper is to develop a model to integrate process planning and resource planning through analysis of the machine tool selection and operations sequencing problem. The model is formulated as a travelling salesman problem with precedence relations. To solve our model, we also propose an efficient genetic algorithm based on topological sort concept.

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