• Title/Summary/Keyword: branch-and-bound

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Branch and Bound Algorithm for the Facility Layout Problem Without Shape Distortion

  • Kim, Chae-Bogk;Kim, Yung-Sik;Lee, Dong-Hoon
    • Journal of the Korean Operations Research and Management Science Society
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    • v.21 no.2
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    • pp.59-70
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    • 1996
  • Given the flow matrix, plant size (rectangle shape) and department sizes, the algorithm in this paper provides the plant layout with rectilinear distance measure. To construct automated facility design, eigenvector approach is employed. A branch and bound computer code developed by Tillinghast is modified to find the feasible fits of departments without shape distortion (see [1])in the plant rectangle. The computational results compared with CRAFT are shown.

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A Branch and Bound Algorithm for the Transportation Problem under Limited Company Owned Vehicles (제한된 수의 자가차량을 이용한 수송문제의 분지한계법)

  • 진희채;박순달
    • Korean Management Science Review
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    • v.10 no.1
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    • pp.207-216
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    • 1993
  • The purpose of this paper is to develop a branch and bound algorithm for the transportation problem with a limited number of company owned vehicles. First, we find an initial solution by solving quasi-assignment subproblem induced by relaxing constraints of the vehicle capacity and illegal tours elimination equations. Second, we build routing from the assignment, and if there is a routings which violates relaxed constraints, we introduce branches of the subproblem in order to remove it. After all branches are searched, we get the optimal solution.

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A Branch-and-Bound Algorithm for the Optimal Vehicle Routing (최적차량운행을 위한 분지한계기법)

  • Song Seong-Heon;Park Sun-Dal
    • Journal of the military operations research society of Korea
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    • v.9 no.1
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    • pp.75-85
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    • 1983
  • This study is concerned with the problem of routing vehicles stationed at a central depot to supply customers with known demands, in such a way as to minimize the total distance travelled. The problem is referred to as the vehicle routing problem and is a generalization of the multiple traveling salesmen problem that has many practical applications. A branch-and-bound algorithm for the exact solution of the vehicle routing problem is presented. The algorithm finds the optimal number of vehicles as well as the minimum distance routes. A numerical example is given.

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An On-line Algorithm for Machine Layout Problem (기계 배치 문제의 온라인 알고리즘)

  • Wang, Gi-Nam
    • Journal of the Korean Society for Precision Engineering
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    • v.12 no.6
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    • pp.27-36
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    • 1995
  • This paper covers algorithms to determine a machine assignment strategy to locations on a single straight track by minimizing the total backtrack distance. Three different algorithms ar presented: an efficient heuristic procedure, the branch-and-bound algorithm, and the nerual network approach. Simulation results show that the proposed algorithms have potential power to design an on-line optimizer.

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Layup Optimization for Composite Laminates with Discrete Ply Angles (이산 섬유 배열각을 이용한 복합재료 적층 평판의 최적 설계)

  • Kim, Tae-Uk
    • Proceedings of the KSME Conference
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    • 2001.06a
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    • pp.734-739
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    • 2001
  • In this paper, an algorithm for stacking sequence optimization which deals with discrete ply angles is used for optimization of composite laminated plates. To handle discrete ply angles, the branch and bound method is modified. Numerical results show that the optimal stacking sequence is found with fewer evaluations of objective function than expected with the size of feasible region, which shows the algorithm can be effectively used for layup optimization of composite laminates..

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Factory Layout and Aisle Structure Design Considering Dimension Constraints and Door Locations (형태 제약과 출입구를 고려한 설비 배치 및 복도 구조 디자인)

  • Chae-Bogk Kim
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.26 no.3
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    • pp.58-66
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    • 2003
  • The cut tree approach of Montreuil and Ratliff [16] and eigenvector approach [10] are used to automatically draw a feasible facility layout with aisle structure. The department arrangement can minimize an aisle distance criterion considering door locations and dimension constraints. The aisle distance is measured by the door to door distance between departments. An eigenvector and cut tree approaches [1] are implemented based on the branch and bound technique in Kim et al. [2] in order to obtain feasible layouts. Then, the algorithm to fix the door location of each department is developed. After the door locations are determined, the factory layout is evaluated in terms of aisle distance. The aisle structure is obtained by expanding the original layout. The solution is kept until we will find better factory layout. The proposed approach based on the branch and bound technique, in theory, will provide the optimal solution. If the runs are time and/or node limited, the proposed method is a strong heuristic. The technique is made further practical by the fact that the solution is constrained such that the rectangular shape dimensions length(l) and width(w) are fixed and a perfect fit is generated if a fit is possible.

Branch-and-Bound Based Heuristic Scheduling for the Single-Hoist and Multiple-Products Production System (단일 호이스트 생산시스템에서 다양한 주문을 처리하기 위한 분지한계 기반의 휴리스틱 일정계획)

  • Lee, Jungkoo;Kim, Jeongbae;Koh, Shiegheun
    • Journal of Korean Institute of Industrial Engineers
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    • v.42 no.3
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    • pp.173-181
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    • 2016
  • This paper deals with the single-hoist and multiple-products scheduling problem. Although a mixed integer linear programming model for the problem was developed earlier, a branch-and-bound based heuristic algorithm is proposed in this paper to solve the big-size problems in real situation. The algorithm is capable of handling problems incorporating different product types, jobs in the process, and tank capacities. Using a small example problem the procedure of the heuristic algorithm is explained. To assess the performance of the heuristic we generate a bigger example problem and compare the results of the algorithm proposed in this paper with the optimal solutions derived from the mathematical model of earlier research. The comparison shows that the heuristic has very good performance and the computation time is sufficiently short to use the algorithm in real situation.

A branch and bound algorithm for solving a capacitated subtree of a tree problem in local access telecommunication network

  • Cho, Geon
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1995.09a
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    • pp.202-210
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    • 1995
  • Given a tree T with a root node 0 having the capacity H and a profit $c_{v}$ and a demand $d_{v}$ on each node v of T, the capacitated subtree of a tree problem(CSTP) is to find a subtree of T containing the root that has the maximum total profit, the sum of profits over the subtree, and also satisfies the constraint of which the sum of demands over the subtree must be less than or equal to H. We first define the so-called critical item for CSTP and find an upper bound on the linear programming relaxation of CSTP. We then present our branch and bound algorithm for solving CSTP and finally report the computational results on a set of randomly generated test problems.s.s.

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An Improvement of Algorithms for Assembly-type Flowshop Scheduling Problem with Outsourcing (부품외주를 고려한 조립형 Flowshop 일정계획 해법 개선)

  • Yoon, Sang-Hum;Juhn, Jae-Ho
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.31 no.2
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    • pp.80-93
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    • 2008
  • This paper improves algorithms for an assembly-type flowshop scheduling problem in which each job is to assemble two types of components and makespan is the objective measure. For the assembly, one type of the components is outsourced with job-dependent lead time but the other type is fabricated in-house. When both components for a job are prepared, the assembly operation for the job can be started. This problem had been proved to be NP-Complete, so branch-and-bound (B&B) and heuristic algorithms have already been developed. In this paper, we suggest other dominance rules, lowerbound and heutistic algorithms. Also, we develop a new B&B algorithm using these improved bound and dominance rules. The suggested heuristics and B&B algorithm are compared with existing algorithms on randomly-generated test problems.

Two-sided assembly line balancing using a branch-and-bound method (분지한계법을 이용한 양면조립라인 밸런싱)

  • Kim, Yeo-Keun;Lee, Tae-Ok;Shin, Tae-Ho
    • Journal of Korean Institute of Industrial Engineers
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    • v.24 no.3
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    • pp.417-429
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    • 1998
  • This paper considers two-sided (left and right side) assembly lines which are often used, especially in assembling large-sized products such as trucks and buses. A large number of exact algorithms and heuristics have been proposed to balance one-sided lines. However, little attention has been paid to balancing two-sided assembly lines. We present an efficient algorithm based on a branch and bound for balancing two-sided assembly lines. The algorithm involves a procedure for generating an enumeration tree. To efficiently search for the near optimal solutions to the problem, assignment rules are used in the method. New and existing bound strategies and dominance rules are else employed. The proposed algorithm can find a near optimal solution by enumerating feasible solutions partially. Extensive computational experiments are carried out to make the performance comparison between the proposed algorithm and existing ones. The computational results show that our algorithm is promising and robust in solution quality.

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