• Title/Summary/Keyword: MAKESPAN

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A Scheduling Method for the m-Machine n-Job Flow-Shop Problem by Gantt Chart (간트 차아트를 이용한 m-기계(機械) n-제품(製品)의 최적(最適) 흐름작업(作業) 순서결정(順序決定))

  • Kim, Nam-Su;Lee, Sang-Yong
    • Journal of Korean Institute of Industrial Engineers
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    • v.12 no.1
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    • pp.13-18
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    • 1986
  • This paper is concerned with flow-shop permutation scheduling problem. This paper presents an algorithm for the minimum makespan sequence. The efficiency of proposed algorithm is demonstrated by comparisons with the existing algorithms: Johnson's, branch & bound method, and heuristic algorithms. The proposed algorithm is more effective than the other algorithms. A numerical example is given to illustrate the procedure.

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Integrated Process Planning and Scheduling in Multiple Plants Chain (다중 플랜트 체인 구조에서 공정계획과 일정계획의 통합)

  • Moon, Chi-Ung;Kim, Kyu-Woong;Kim, Jong-Soo;Hur, Sun
    • IE interfaces
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    • v.13 no.3
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    • pp.388-395
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    • 2000
  • In this paper, we propose an approach for integrated process planning and scheduling through analysis of the alternative operations sequences and machine selection in supply chain with multiple plants. It takes into account such factors alternative machine, alternative operations sequences, setup time, transportation time between plants, along with other manufacturing factors. The objective of the model is to minimize makespan of machine schedules for all parts, determines operations sequence for each part, and selects a machine for each operation simultaneously. Examples are presented to demonstrate the effectiveness of the proposed approach.

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Selection of Assembly Sequences Based on Flexible Assembly Systems Performance

  • Jeong, Bong-Ju
    • Management Science and Financial Engineering
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    • v.1 no.1
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    • pp.67-90
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    • 1995
  • In planning an assembly system, choosing the proper assembly sequence is one of the most important decisions because it significantly affects the costs associated with the assembly process. This paper deals with the selection of assembly sequences in flexible assembly systems. The selection criterion is the minimization of makespan to complete all assembly products. This problem is formulated as a "modified FAS scheduling problem" (MFASSP) and its scheduling procedure is described. The experimental results show that the procedure is very efficient for both quality of solution and computation time.

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Parallel Machines Scheduling with GoS Eligibility Constraints : a Survey (GoS 상황에서의 스케줄링 문제 : 문헌 조사)

  • Lim, Kyung-Kuk
    • Journal of Korean Institute of Industrial Engineers
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    • v.36 no.4
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    • pp.248-254
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    • 2010
  • In this paper, we survey the parallel machines scheduling problem with GoS eligibility constraints so as to minimize the makespan. Our survey covers off-line, online and semi-online scheduling problems. In the case of online scheduling, we only focus on online scheduling one by one. Hence we give an introduction to the problem and present important results of the problem.

Loading and Routing Problems for Schedulability in a Flexible Manufacturing Environment

  • 정병희;송관우
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1998.10a
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    • pp.304-308
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    • 1998
  • With the advances in concurrent engineering, schedulability has become an important design issue in machine loading and routing procedure. In this paper, four rules to improve schedulability of loading and routing are formulated as a mixed-integer programming model based on machine, routing and tool flexibilities. In this model, these rules are represented as an objective function or constraints. The impact of rules on the quality of schedules for the result of loading and routing is measured with makespan, throughput and average machine utilization.

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A rounding algorithm for altemate machine scheduling (대안기계 스케쥴링 문제에 대한 라운딩 알고리듬)

  • Hwang, Hak-Jin
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2006.11a
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    • pp.147-157
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    • 2006
  • In this paper we consider alternate m machine scheduling problem in which each job having at most two eligible machines should be assigned with the objective of makespan minimization. For this problem, we propose a $O(m2^m)$ time rounding algorithm with performance ratio at most 1.5. For a little general problem where each job can be processed at most three machines, we prove that there cannot exist a polynomial time algorithm with performance ratio less than 1.5.

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A Study for Scheduling Jobs on Unrelated Parallel Processors

  • Kang, Suk-Ho;Park, Sung-Soo
    • Journal of the military operations research society of Korea
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    • v.9 no.1
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    • pp.51-61
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    • 1983
  • Lagrangian relaxation is used to the problem of scheduling jobs on unrelated parallel processors with the objective of minimizing makespan. The implicit condition for optimality is drawn out explicitly in order to apply the subgradient algorithm. To obtain the optimal solution, branch-and-bound-search method is devised. In the search, the special structure of the problem is exploited effectively, Some computational experiences with the algorithm are presented, and comparisons are made with the Land and Doig method.

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A PTAS for nonsimultaneous parallel machine scheduling (가용시간이 서로 다른 병렬기계 스케줄링 문제에 대한 PTAS)

  • Hwang Hark-Chin
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2003.05a
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    • pp.145-150
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    • 2003
  • The parallel machine scheduling problem or assigning n jobs on m identical machines with the objective of minimizing makespan is considered. In this note, we apply the PTAS (Polynomial Time Approximation Scheme) or Hochbaum and Shmoys to our problem and show that it is still a PTAS for our problem.

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Production Scheduling for a Flexible Manufacturing Cell

  • 최정상
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1998.03a
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    • pp.209-213
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    • 1998
  • This study considers flowshop scheduling problem related to flexible maufacturing cell in which consists of two machining centers, robots for loading/unloading, and an automated guided vehicle(AGV) for material handling between two machining centers. Because no machinng center has buffer storage for work in process, a machining center can not release a finished job until the empty AGV is available at that machining center. While the AGV cannot tranfer an unfinished job to a machining center until the machining center empty. In this paper, an new heuristic algorithm is given to find the sequence that minimize their makespan.

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A Study on Operator Allocation Problem in Cellular Manufacturing Systems (셀 생산방식 시스템에서 작업자 할당문제에 관한 연구)

  • 홍상우
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.23 no.61
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    • pp.23-31
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    • 2000
  • This paper addresses the static operator allocation problem in celluar manufacturing systems(CMS). An assembly environment is considered where each component going into the final product is manufactured in an individual cell. There are m such cells and it is required to manufacture n varieties of products where n>m. An mathematical model and two heuristic algorithms for static operators allocation to the cells to balance workload for minimizing makespan are developed and tested.

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