• 제목/요약/키워드: Setup cost

검색결과 222건 처리시간 0.028초

MAINTENANCE SETUP AND SETUP PERFORMANCE IMPROVEMENT IN AN UNRELIABLE PRODUCTION SYSTEM

  • Lee, Chang-Hwan
    • Management Science and Financial Engineering
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    • 제3권1호
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    • pp.57-74
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    • 1997
  • An EOQ-like inventory model for a manufacturing process is studied. The system is assumed to deteriorate during the production process. The results are either the production of a number of defective items, or the breakdown of the production machine. The optimal production lot size is derived. The model is extended to the case in which the probabilities of making defective items and machine breakdowns are a function of both the quantity (amount) and quality (performance) of the consumed setup cost (including the preventive maintenance cost). We further assume that the setup performance can be improved by investing in the performance improvement program. Hence, the same or a better setup outcome can be achieved with a lower setup cost. We then investigate the optimal setup cost and investment policy simultaneously, thereby achieving a better process quality and setup cost reduction concurrently.

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다종제품의 동적 로트크기결정 모형에서의 생산준비비용 절감효과에 관한 연구 (Setup Cost Reduction in a Multi-Product Dynamic Lot-Sizing Model)

  • 이운식;주철민
    • 산업공학
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    • 제13권2호
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    • pp.217-224
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    • 2000
  • This paper analyzes the effects of setup cost reduction in a dynamic lot-sizing model for a single-facility multi-product problem. In the model, demands for each product are known, no backlogging is allowed, and a single resource is employed. Also, setup cost is defined as a function of capital expenditure to invest in setup cost reduction. Furthermore, in each production period the facility (or plant) produces many products, each representing a fixed part of the involved production activity (or input resource quantity). In this paper, the structure of the optimal solution is characterized and an efficient algorithm is proposed for simultaneously determining the optimal lot size with reduced setup cost and the optimal investment in setup cost reduction. Also, the proposed algorithm is illustrated by a numerical example with a linear and an exponential setup reduction functions.

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Designing a Coordinated Setup Cost Reduction Program of a Supply Chain

  • Lee, Chang-Hwan;Pae, Jae-H.
    • Management Science and Financial Engineering
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    • 제13권2호
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    • pp.117-139
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    • 2007
  • This paper contributes by incorporating works addressing supply chain coordination and investing in setup reduction program. Consider a two-echelon, EOQ-like inventory system consisting of a supplier and a buyer. We assume that both the supplier and the buyer can invest in setup cost reduction programs in order to benefit from small order sizes. However, the costs of investing in setup cost reduction programs are different for the two parties, leading to mismatches in individually optimal setup costs and order cycle times. We propose a supply chain coordination contract that makes use of quantity discount as an incentive transfer scheme for supply chain coordination.

통합 주문 및 가동준비단축 모형 (An Integrated Ordering and Setup Cost Reduction Model)

  • 이창환
    • 한국경영과학회지
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    • 제25권3호
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    • pp.49-64
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    • 2000
  • A vendor supplies a product to a sole/major buyer on a lot-for-lot basis under deterministic inventory control conditions. The basic premise is that the setup cost reduction technologies are available to both the buyer and the vendor, and that the vendor's inventory and setup reduction investment costs differ from the buyer's. Therefore, an individually designed ordering and setup cost reduction policy will likely cause mismatches between the vendor's and the buyer's optimal cycle times. For this situation, we show that a joint optimal setup cost reduction and ordering policy, together with an appropriate side payment(quantity discount or premium price) schedule, can be designed in a spirit in a spirit of coordination to eliminate mismatches in individual optimal cycle times.

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Heuristic Approach for Lot Sizing and Scheduling Problem with State Dependent Setup Time

  • Han, Jung-Hee
    • Industrial Engineering and Management Systems
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    • 제10권1호
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    • pp.74-83
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    • 2011
  • In this paper, we consider a new lot-sizing and scheduling problem (LSSP) that minimizes the sum of production cost, setup cost and inventory cost. Setup carry-over, setup overlapping, state dependent setup time as well as demand splitting are considered. For this LSSP, we develop a mixed integer programming (MIP) model, of which the size does not increase even if we divide a time period into a number of micro time periods. Also, we develop an efficient heuristic algorithm by combining a decomposition scheme with a local search procedure. Test results show that the developed heuristic algorithm finds a good quality (in practice, even better) feasible solution using far less computation time compared with the CPLEX, a competitive MIP solver.

컨베이어 시스템 분기점에서의 셋업 최소화 문제 (Setup Minimization Problem in a Diverging Point of the Conveyor System)

  • 김형태;한용희
    • 산업경영시스템학회지
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    • 제36권3호
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    • pp.95-108
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    • 2013
  • The problem of constrained sequencing of a set of jobs on a conveyor system with the objective of minimizing setup cost is investigated in this paper. A setup cost is associated with extra material, labor, or energy required due to the change of attributes in consecutive jobs at processing stations. A finite set of attributes is considered in this research. Sequencing is constrained by the availability of conveyor junctions. The problem is motivated by the paint purge reduction problem at a major U.S. automotive manufacturer. We first model a diverging junction with a sequence-independent setup cost and predefined attributes as an assignment problem and this model is then extended for a more general situation by relaxing the initial assumptions in various ways.

입찰 평가 문제의 배정-변경 최적화 (Assignment-Change Optimization for the Problem of Bid Evaluation)

  • 이상운
    • 한국인터넷방송통신학회논문지
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    • 제21권4호
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    • pp.171-176
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    • 2021
  • 본 논문은 설비 설치비용과 판매단가로 구성된 다수의 구매처 입찰정보로부터 구성품을 구매함에 있어 최소의 비용으로 구매하기 위해 구매처와 구매 물량을 선정하는 입찰평가 문제를 다룬다. 이 문제에 대해 기존에 알려진 방법은 분기한정 법(BB)과 분기절단 법(BC)이 알려져 있다. 그러나 이들 방법으로 얻은 해가 최적 해가 되지 않는 문제점이 있다. 본 논문에서는 판매단가 순위 또는 설치비용 순위 우선 구매물량 배정원칙을 적용하여 초기 실현 가능 해를 얻고, 판매단가 또는 설치비용을 고려하여 물량을 이동(구매업체 변경)시키는 최적화를 수행하는 방법을 제시하였다. 제안된 방법을 실험 데이터에 적용한 결과 BB와 BC에 비해 구매비용을 크게 절감할 수 있었다.

프로세스 품질 개선과 셋업 절감을 고려한 연속 및 불연속 배송 환경에서의 최적 불완전 품질 재고 모형 (Optimal Imperfect-Quality Inventory Models for Continuous and Discrete Shipping with Process Improvement and Setup Reduction)

  • 김대수;유승호
    • 한국경영과학회지
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    • 제34권1호
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    • pp.11-28
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    • 2009
  • Intelligent investment in setup cost reduction and process reliability improvement is crucial to an emerging integrated lean six sigma practice today. This study examines a cost-minimizing problem of jointly determining production lot size, setup cost reduction, and process reliability improvement decisions for a manufacturer with an imperfect production process. We develop models for previously untapped discrete shipping in a supply chain context as well as continuous shipping and solve them optimally using differential calculus and nonlinear programming. We also conduct analytic and numerical sensitivity analyses to provide various important managerial insights into practices.

Setup cost와 Backorder rate를 고려한 확률적 재고모형에 관한 연구 (The study of stochastic inventory model with setup cost and backorder rate)

  • 유승우;서창현;김경섭
    • 한국시뮬레이션학회:학술대회논문집
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    • 한국시뮬레이션학회 2003년도 춘계학술대회논문집
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    • pp.129-134
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    • 2003
  • In this paper, we determine optimal reduction in the lead time and setup cost for some stochastic inventory models. And we propose more general model that allow the backorder rate as a control variable. We first assume that the lead time demand follows a normal distribution. And we assume that the backorder rate is dependent on the length of lead time through the amount of shortages. The stochastic models analyzed in this paper are the classical continuous and periodic review policy models with a mixture of backorders and lost sales. For each of these models, we provide a sufficient conditions for the uniqueness of the optimal operating policy. We also develop algorithms for solving these models and provide illustrative numerical examples.

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안정화기간을 고려한 최적생산량의 결정 (Determination of the Economic Production Quantity for a Manufacturing Process with Stabilization Period)

  • 함주호;김승한;이건호
    • 대한산업공학회지
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    • 제20권3호
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    • pp.93-104
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    • 1994
  • One of the typical assumptions of the studies to determine economic production quantity is that yield rate of a given manufacturing process is 100% or constant after setup. However, in the real world, there are many manufacturing processes of which yield rates are quite low just after setup and then increasing with time until they reach the target rates which are set strategically. This period is usually called "stabilization period". During the stabilization period, defectives are produced, which incur cost (defective cost). In this study, an optimal production quantity for this situation is presented. Also, it is shown that defective cost acts like setup cost and therefore, increases the economic production quantity.

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