• 한국건설관리학회논문집
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• 제12권1호
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• pp.33-42
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• 2011

자재 및 재고관리에 관한 부분은 전 산업 분야에서 기업의 이익을 위해 고려되는 주요 요소 중 하나이지만 국내 건설 프로젝트에서는 조달 관리의 중요성이 상대적으로 평가절하 되어왔고 기존의 재고관리에 관한 연구는 개별 요소로 한정되어 많이 연구되었으며 제조업의 이론을 도입하는 단계에 머물렀다. 따라서 건설 프로젝트의 자재 및 재고관리를 전체적인 프로세스 관점에서 바라보고 개선하며 기존 이론의 도입에 더하여 건설 프로젝트 특성 반영이 필요하다. 본 연구에서는 계획 단계의 현장 관점에서 야적장의 면적과 재고량을 이용하여 경제적주문량을 결정하는 자재관리 프로세스를 제안하고 이를 건설 현장의 기존 프로세스와 비교하여 그 유용성을 검증하였다.

• 경영과학
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• 제5권2호
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• pp.48-56
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• 1988

본 연구에서는 생산능력제약이 주어지는 경우에 있어서 가동준비시간의 절감효과 분석을 위한 모형을 수립하고 이 모형을 이용하여 여러가지 분석을 하고 마지막으로 알고리즘을 제시하였다. 특히 동적수요를 가정함으로써 기존의 EOQ모형연구에서 분석할 수 없었던 분석이 가능하였고, 수요가 변동하는 상황이라 하더도 생산능력제약이 없는 경우의 결과가 나올 수 있음을 보였다.

• 한국유통학회지:유통연구
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• 제2권1호
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• pp.143-174
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• 1997

The model applied in this paper is based on the theory of economic order quantity (EOQ). EOQ model is introduced to explain the improvement of the transaction efficiency through the cooperative purchase. We examine explicitly how horizontal cooperation affects vertical transactions. A result of the analysis is that a seller can prefer transacting with a cooperative rather than with each buyer separately, even if he reduces the selling price of the product. Without increasing the demand for the product, this result is that dealing with a cooperative, rather than separately with each buyer, decreases the transaction cost for the seller-buyers system, the cost reduction more than off-setting the effect of price decrease on the sellers profit. For a coopative consisting of any number of buyers, Pareto efficient ordering policies that maximize the joint cost saving for the seller-buyers system are identified. We then discuss the conditions under which a cooperative under consideration can be modified to increase efficiency gain. Next, we relax the assumption that all buyers participate in a single cooperative and examine the issue of how many cooperatives, each consisting of a subset of the buyers, should be formed to maximize the total cost saving for the seller-buyers system. Finally, the issue of shapley value to divide the cooperatives gain among its members is discussed.

• 제어로봇시스템학회논문지
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• 제4권6호
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• pp.802-810
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• 1998

The purpose of this study is to find the analytic solution of determining the optimal capacity of processes and storages to meet the product demand. Recent trend to reduce product delivery time and to provide high quality product to customer requires the increasing capacity of storage facilities. However, the cost of constructing and operating storage facilities is becoming substantial because of increasing land value, environmental and safety concern. Therefore, reasonable decision making about the capacity of processes and storages is important subject for industries. The industrial solution for this subject is to use the classical economic lot sizing method, EOQ(Economic Order Quantity) model, trimmed with practical experience but the unrealistic assumption of EOQ model is not suitable for the chemical plant design with highly interlinked processes and storages. This study, a first systematic attempt for this subject, clearly overcomes the limitation of classical lot sizing method. The superstructure of the plant consists of the network of serially and/or parallelly interlinked processes and storages. A novel production and inventory analysis method, PSW(Periodic Square Wave) model, is applied. The objective function of optimization is minimizing the total cost composed of setup and inventory holding cost. The advantage of PSW model comes from the fact that the model provide a set of simple analytic solution in spite of realistic description of material flow between process and storage. The resulting simple analytic solution can greatly enhance the proper and quick investment decision for the preliminary plant design confronting diverse economic situation.

• 대한산업공학회지
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• 제20권3호
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• pp.117-124
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• 1994

In this paper an inventory model is presented for determining the ordering schedule in which the demand rate is changing linearly with time and the decay is assumed to be a constant rate of the on-hand inventory. An easy to use heuristic is developed to find the times and sizes of replenishments so as to keep the total of ordering, inventory carrying and deteriorating costs as low as possible. Solutions of the model to test problems show that our heuristic model outperforms other existing models in the literature without sacrificing the computational complexity. When there is no deterioration, the model developed is related to the corresponding model of nondeteriorating items.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2004년도 춘계공동학술대회 논문집
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• pp.224-232
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• 2004

소매점에서 판매를 최대화하여 이익을 극대화하기 위해서는 투자비용을 최소화하고 재고를 최소로 유지하며, 결품을 최소화해서 매출을 보호해야 한다. 수요의 동향이 다양화 됨으로써 예측이 점점 어려워지고, 재고를 최소화하고, 빠른 납기를 충족시키고, 판매 기회의 손실을 최소화 하기란 점점 어려워지고 있다. 또한 매출의 보호와 재고의 축소는 서로 상반되는 내용을 담고 있다. 전통 Industrial Engineering(IE)에서 경제적 주문량(EOQ)을 결정하여 재고 회전율을 높이고 발주 비용과 재고 비용을 최소화하는 연구는 많이 다루어져 왔다. 본 논문에서는 TOC의 쓰루풋 증대의 관점에서 최적의 재고 보충 관리 방안을 제시하고자 한다.

• 대한산업공학회지
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• 제41권3호
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• pp.324-329
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• 2015

Though the supplier diversification is considered as a vital tool to mitigate the risk due to supply chain disruptions, there are results which show the optimality of the sole sourcing. This paper further generalizes the results to show that the sole sourcing is optimal under very mild conditions. Discussion on why the sole sourcing is optimal is given with the insight on the value of supplier diversification.

• Journal of applied mathematics & informatics
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• 제6권2호
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• pp.539-552
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• 1999

An order-level inventory model for a perishable product with a time-dependent demand is developed for a fixed planning pe-riod allowing backlogging in all cycles within the said period. The market demand is assumed to decrease exponentially as time elapses. The average system cost is derived and its optimization procedure is illustrated with a numerical example. Sensitivity of the optimal so-lution to changes in the values of different parameters of the system is also analysed.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2002년도 춘계학술대회
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• pp.237-241
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• 2002

This paper deals with the problem of determining the buyer's economic lot sizing policy for exponentially deteriorating products under trade credit. It is also assumed that the ordering cost consists of a fixed set-up cost and a freight cost, where the freight cost has a quantity discount offered due to the economies of scale. We formulate the mathematical model and the solution algorithm is developed based on the properties of an optimal solution.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2002년도 춘계학술대회
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• pp.243-247
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• 2002

This paper deals with the problem of determining the buyer's economic lot sizing policy for exponentially deteriorating products under trade credit. Assuming that the supplier's credit terms are already known and the length of delay is a function of the buyer's order size, we formulate the mathematical model and the solution algorithm is developed based on the properties of an optimal solution.