• Title/Summary/Keyword: Planning Problems

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A comprehensive approach for managing feasible solutions in production planning by an interacting network of Zero-Suppressed Binary Decision Diagrams

  • Takahashi, Keita;Onosato, Masahiko;Tanaka, Fumiki
    • Journal of Computational Design and Engineering
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    • v.2 no.2
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    • pp.105-112
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    • 2015
  • Product Lifecycle Management (PLM) ranges from design concepts of products to disposal. In this paper, we focus on the production planning phase in PLM, which is related to process planning and production scheduling and so on. In this study, key decisions for the creation of production plans are defined as production-planning attributes. Production-planning attributes correlate complexly in production-planning problems. Traditionally, the production-planning problem splits sub-problems based on experiences, because of the complexity. In addition, the orders in which to solve each sub-problem are determined by priorities between sub-problems. However, such approaches make solution space over-restricted and make it difficult to find a better solution. We have proposed a representation of combinations of alternatives in production-planning attributes by using Zero-Suppressed Binary Decision Diagrams. The ZDD represents only feasible combinations of alternatives that satisfy constraints in the production planning. Moreover, we have developed a solution search method that solves production-planning problems with ZDDs. In this paper, we propose an approach for managing solution candidates by ZDDs' network for addressing larger production-planning problems. The network can be created by linkages of ZDDs that express constraints in individual sub-problems and between sub-problems. The benefit of this approach is that it represents solution space, satisfying whole constraints in the production planning. This case study shows that the validity of the proposed approach.

A Study on Integration of Process Planning and Scheduling Using AND/OR Graph (AND/OR 그래프를 이용한 공정계획과 일정계획의 통합에 관한 연구)

  • Kim, Ki-Dong;Jeong, Han-Il;Chung, Dae-Young;Park, Jin-Woo
    • Journal of Korean Institute of Industrial Engineers
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    • v.23 no.2
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    • pp.323-341
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    • 1997
  • Traditionally, the Process Planning problems and the Scheduling problems have been considered as independent ones. However, we can take much advantages by solving the two problems simultaneously. In this paper, we deal with the enlarged problem that takes into account both the process planning and the scheduling problems. And we present a solution algorithm for the problem assuming that the given process plan data is represented by AND/OR graph. A mathematical model(mixed ILP model) whose objective is the minimization of the makespan, is formulated. We found that we can get the optimal solutions of the small-size problems within reasonable time limits, but not the large-size problems. So we devised an algorithm based on the decomposition strategy to solve the large-scale problems (realistic problems) within practical time limits.

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Algorithms for Production Planning and Scheduling in an Assembly System Operating on a Make-to-Order Basis (주문생산방식을 따르는 조립시스템에서의 생산계획 및 일정계획을 위한 알고리듬)

  • Park, Moon-Won;Kim, Yeong-Dae
    • Journal of Korean Institute of Industrial Engineers
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    • v.24 no.3
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    • pp.345-357
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    • 1998
  • This paper focuses on production planning and scheduling problems in an assembly system operating on a make-to-order basis. Due dates are considered as constraints in the problems, that is, tardiness is not allowed. Since the planning problem is a higher-level decision making than the scheduling problem, the scheduling problem is solved using a production plan obtained by solving the planning problem. We suggest heuristic procedures in which aggregated information is used when the production planning problem is solved while more detailed information is used when the scheduling problem is solved. Since a feasible schedule may not be obtained from a production plan, an iterative approach is employed in the two procedures to obtain a solution that is feasible for both the production planning and scheduling problems. Computational tests on randomly generated test problems are done to show the performance of these algorithms, and results are reported.

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Action Costs-based Heuristics for Optimal Planning (최적 계획생성을 위한 동작비용 기반의 휴리스틱)

  • Kim, Wantae;Kim, Hyunsik
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.13 no.2
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    • pp.27-34
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    • 2017
  • Highly informative admissible heuristics can help to conduct more efficient search for optimal solutions. However, in general, more informative ones of heuristics from planning problems requires lots of computational effort. To address this problem, we propose an Delete Relaxation based Action Costs-based Planning Graph(ACPG) and Action Costs-based Heuristics for solving optimal planning problems more efficiently. The ACPG is an extended one to be applied to can find action costs between subgoal & goal conditions from the Relaxed Planning Graph(RPG) which is a common means to get heuristics for solving the planning problems, Action Costs-based Heuristics utilizing ACPG can find action costs difference between subgoal & goal conditions in an effective way, and then consider them to estimate the goal distance. In this paper, we present the heuristics algorithm to compute Action Costs-based Heuristics, and then explain experimental analysis to investigate the efficiency and the accuracy of the Action Costs-based Heuristics.

The Examming of the Problems in Flexible House Planning (가변형 주거계획의 문제점에 관한 문헌적 연구)

  • 김순경
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 1994.10a
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    • pp.73-78
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    • 1994
  • In this study, we are to exam the flexibility of the house planning in Korean situation. For this, not only the study of literature but the analysis of occupant's behavior are needed. This paper is limited in the research of literature. As results, 4 dimensions of the problems in the flexible house planning are extracted. They are, choice and partispation of occupants, reinvestment of a supplementay expenditures, occupant's preference of flexible house, and the problems of exisitin planning of apartment house.

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A Discussion on the National Land Planning and Use Act from the Rural Planning of View (농촌계획 관점에서 본 국토계획법의 개선방안)

  • Hwang, Han-Cheol
    • Journal of Korean Society of Rural Planning
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    • v.10 no.2 s.23
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    • pp.51-60
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    • 2004
  • Through the fast economic growth since the 1960s, Korea has experienced various problems on land such as urban sprawl, the rapid increase in land prices, land speculation, privatization of the betterment, and so on. To prevent such problems and to enhance harmonious development and conservation, the National Land Planning and Use Act(NLPUA) was established in 2003. The NLPUA which was revised and combined two existing planning laws i.e. the National Land Use Management Act and Urban Planning Act, has an eye to preventing disorderly spatial development, to pursuing environmentally friendly spatial planning, and to following up planned development in non-urbanized area like rural area. This study aims to discuss what should be considered the pending issues after the application of the NLPUA in rural area. On the basis of reviewing the NLPUA in a viewpoint of the rural planning, this study suggests some improvement policy such as considering various rural conditions, securing excellent agricultural land, applying the District Plan II system effectively, reorganizing the planning administrative, and so on.

Factory Planner Application for Planning and Scheduling of Factory on Supply Chain (Supply Chain상에서 공장내의 생산 계획 및 스케줄링을 위한 Factory Planner 적용)

  • 오형술;박경종;이충수
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.25 no.4
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    • pp.8-15
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    • 2002
  • This paper proposes a case study to treat planning and scheduling in factory of supply chain. In fact, the planning and the scheduling of a factory are not easily solved because of constraints of facility resources, material requirements, allowed planning times, and so on. However many packages are developed by vendors in Advanced Planning and Scheduling(APS) aspects to solve these problems. Therefore, in this paper, we analyze problems of an electronic company and apply the tool, Factory Planner(FP), to solve problems. The FP, which was developed by if technologies, is very popular planning and scheduling tool in the world. Also, the tool is successfully applied to many fields.

Information Systems Planning Problems in Not-for-Profit Organisations: The Case of Western Australia

  • Maka Siwale;John Venable
    • Asia pacific journal of information systems
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    • v.30 no.3
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    • pp.664-694
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    • 2020
  • Much has been written on Information Systems Planning in the for-profit organisations, but little is known about it in the Not-for-Profit sector, particularly in the Australian context. This paper has attempted to conceptualise the problem of Information Systems planning in the Not-for-Profit organisations. It provides insight into Information Systems Planning practices in Not-for-Profit-Organisations and the problems of current Information Systems Planning practices in Not-for-Profit-Organisations. The contribution of this paper is two folds, theoretically and for practitioners. Theoretically, it has provided a model that enables people to understand why or why not Not-for-Profit-Organisations do or do not conduct Information Systems Planning. Regarding practitioners, the factors identified in this study would help planners, managers and executives to understand the key areas and plan accordingly and for donors they would be able to understand where are their contributions needed the most and be able to follow up and ensure that their donations/contributions are utilised in the right areas hence increase Not-for-Profit-Organisations accountability with regards to planning for Information Systems.

Decision-making Problems for the Operation of Container Terminals (컨테이너터미널 운영을 위한 의사결정문제의 소개)

  • Kim, Kap Hwan
    • Journal of Korean Institute of Industrial Engineers
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    • v.33 no.3
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    • pp.290-302
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    • 2007
  • This paper introduces several decision-making problems that need to be solved in order to facilitate the efficient operation of container terminals. These decision-making problems include the berth planning problem, the quay crane scheduling problem, the unload/load sequencing problem, the yard allocation problem, and the short-term scheduling of transporters and yard cranes. These problems can be classified into strategic decision problems, tactical decision problems, and real time operational decision problems. This paper proposes definitions of the problems that can be used to develop mathematical models for the problems.

A Study on Propulsion system of Rural Development Program in Chungnam Province (지방정부의 농촌개발사업 추진체계의 문제점과 개선과제 - 충청남도를 중심으로 -)

  • Cho, Young-Jae
    • Journal of Korean Society of Rural Planning
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    • v.16 no.1
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    • pp.35-47
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    • 2010
  • With the cognition of the problems on propulsion system of rural development program, the requirement for accurate diagnosis of the problems and for reform scheme is increasing. This study was performed to solve the above requirement especially on the level of a local government, Chungnam province as an instance. For accurate diagnosis of the problems, the present situation of propulsion system, i.e. organization and governance, planning and policy making, implementation and supervision of rural development program was investigated, and the cognition of public officials and specialists was surveyed. From the study, it showed that the problems of propulsion system for rural development program in Chungnam province are duplication of work sphere among departments, formal administration of governance, an absence of long-term plan with vision and strategy, and absence of department in charge of comprehensive supervision and so on. As a result of the study 9 reform schemes to solve the problems were suggested.