• 제목/요약/키워드: Holding Cost

검색결과 221건 처리시간 0.028초

Robust Design Method for Complex Stochastic Inventory Model

  • Hwang, In-Keuk;Park, Dong-Jin
    • Proceedings of the Korean Operations and Management Science Society Conference
    • /
    • 한국경영과학회/대한산업공학회 1999년도 춘계공동학술대회:정보화시대의 지식경영
    • /
    • pp.426-426
    • /
    • 1999
  • ;There are many sources of uncertainty in a typical production and inventory system. There is uncertainty as to how many items customers will demand during the next day, week, month, or year. There is uncertainty about delivery times of the product. Uncertainty exacts a toll from management in a variety of ways. A spurt in a demand or a delay in production may lead to stockouts, with the potential for lost revenue and customer dissatisfaction. Firms typically hold inventory to provide protection against uncertainty. A cushion of inventory on hand allows management to face unexpected demands or delays in delivery with a reduced chance of incurring a stockout. The proposed strategies are used for the design of a probabilistic inventory system. In the traditional approach to the design of an inventory system, the goal is to find the best setting of various inventory control policy parameters such as the re-order level, review period, order quantity, etc. which would minimize the total inventory cost. The goals of the analysis need to be defined, so that robustness becomes an important design criterion. Moreover, one has to conceptualize and identify appropriate noise variables. There are two main goals for the inventory policy design. One is to minimize the average inventory cost and the stockouts. The other is to the variability for the average inventory cost and the stockouts The total average inventory cost is the sum of three components: the ordering cost, the holding cost, and the shortage costs. The shortage costs include the cost of the lost sales, cost of loss of goodwill, cost of customer dissatisfaction, etc. The noise factors for this design problem are identified to be: the mean demand rate and the mean lead time. Both the demand and the lead time are assumed to be normal random variables. Thus robustness for this inventory system is interpreted as insensitivity of the average inventory cost and the stockout to uncontrollable fluctuations in the mean demand rate and mean lead time. To make this inventory system for robustness, the concept of utility theory will be used. Utility theory is an analytical method for making a decision concerning an action to take, given a set of multiple criteria upon which the decision is to be based. Utility theory is appropriate for design having different scale such as demand rate and lead time since utility theory represents different scale across decision making attributes with zero to one ranks, higher preference modeled with a higher rank. Using utility theory, three design strategies, such as distance strategy, response strategy, and priority-based strategy. for the robust inventory system will be developed.loped.

  • PDF

Internet Based for Computer Integration Manufacturing System

  • Suesut, T.;Hankarjonsook, C.;Tipsuwanporn, V.;Tammarugwattana, N.;Tirasesth, K.
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2003년도 ICCAS
    • /
    • pp.260-263
    • /
    • 2003
  • This paper has developed the computer integration manufacturing system and Internet based tele-operations. The functions of CIMS include production planing, material requirement planning, work order generation, process control, quality control, shipping planning, warehouse and inventory management and material cost accounting.[1] In this paper focuses on the automatic warehouse control and inventory management by developing the information system as well as the Internet-based integration. The system overview is divided into three parts, the mechanical system, the computer and developed software to control and manage the information and the communication system. The mechanical system consists of the warehouse machine and forklift mobile robot controlled by programmable logic controller (PLC). The computer works on many functions such as control station interfaces with PLC, managing database and inventory, and Internet server to broadcast the inventory database to users via World Wide Web and monitoring the operation on web camera. Our scheme the inventory database can be checked easily anywhere and anytime when the users connect to the Internet. In this article, the lead-time and inventory level can be reduced therefore the holding cost and operating time is also decreased.

  • PDF

A Development of the Optimized Shielding Room Design Simulator for HEMP Protection (HEMP 방호용 차폐실 최적설계를 위한 시뮬레이터 개발)

  • Min, Gyung-Chan;Kim, Dong-Il
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • 제10권4호
    • /
    • pp.121-126
    • /
    • 2010
  • Regarding HEMP has been studied as few thousand of paper by major nuclear bomb holding countries with USA for the self protection against nuclear bomb attract. Major HEMP protection facilities are consist of the shielding, filtering, grounding and high voltage protection circuits. Shielding room construction required a highest cost among the key protective facilities. Most of a theoretical formulas listed on the paper and related books has a little correlations in the certain frequency band between the theoretical formulas and field measuring results. For the reasons we proposed the advanced new theoretical formulas and developed the computer simulation S/W as enough as apply to the cost effective shielding room design for HEMP considering the various structural constants.

A Study on the NiO-doped Willemite Pigments (Ni-doped Willemite계 청색안료에 관한 연구)

  • Lee, Chi-Youn;Lee, Hyun-Soo;Lee, Byung-Ha
    • Journal of the Korean Ceramic Society
    • /
    • 제48권2호
    • /
    • pp.134-140
    • /
    • 2011
  • To study the effect of color development of Ni-doped willemite blue pigments, five batches of compositions were prepared and fired at $1350^{\circ}C$/hold for 1 h. When Ni was substituted for ZnO by 0.03 mole the optimum result were obtained. Then they were fired at $1300^{\circ}C$ and held for 1, 2, 4 and 6 h respectively for the purpose sake. XRD, Raman spectroscopy, FT-IR, UV-vis were used to analyze the results of experiment. The substitution of 0.03mole Ni for Zn was most optimum and which produced good willemite at the temperature of $1300^{\circ}C$, holding for 6 h. In ceramic arts, cobalt has been used for blue coloring, in most cases, despite of its high cost. If the low cost Ni-doped willemite blue pigments supplies for them with stable and multiple shades of blue pigment, using NiO at high temperature, it would provide various blues for ceramic wares.

Heuristic for Distribution Planning in Capacitated Multi-echelon Supply Chains (생산 능력 제한이 있는 다계층 공급사슬의 분배계획을 위한 발견적 기법)

  • Kwon, Ick-Hyun;Shin, Hyun-Joon;Kim, Sung-Shick
    • IE interfaces
    • /
    • 제19권2호
    • /
    • pp.124-132
    • /
    • 2006
  • The system under study is a single item, multi-echelon distribution system with a capacitated production facility. All the nodes at the downstream ends are demand-sites, i.e., ordered items are delivered to the customers from the node. Also any transshipment depots in the midstream can be demand-sites as well. For a given planning period, at each of demand-site, demand is forecasted and known. Our objective is to minimize the average system cost per period which is the sum of holding and backorder costs in the entire network. Due to the capacity restrictions, it is difficult to establish efficient distribution planning. To overcome such a difficulty and obtain a reasonable and better solution, we convert this problem into a single machine earliness and weighted tardiness scheduling. We propose a simple but cost-effective heuristic for this problem. The experimental results showed that the proposed heuristic obtained much better solutions compared with another approach.

Economic Order Quantity and Discount Pricing Policy for the Monopsony Related to the Weapon System Acquisition.

  • 최석철
    • Journal of the military operations research society of Korea
    • /
    • 제23권2호
    • /
    • pp.72-84
    • /
    • 1997
  • In this paper, we consider an economic order quantity(EOQ) and an optimal discount pricing policy for the monopsony related to the weapon system acquisition. In the monopsony case, a buyer wishes to maximize the profit. However, a seller wants to minimize the total inventory related cost since a buyer can determine the purchase price for the product. We develop a generalized version of EOQ model for the monopsony, including one seller-one buyer model and two seller-one buyer model. A model of buyer reaction to any given pricing scheme is developed to show that there exits a unified pricing policy which motivates the buyer to increase its ordering quantity per order, thereby reducing the joint(buyer and seller) ordering and holding costs in the system.

  • PDF

Development of Stamping Process Optimization System: Integration of Optimal Blank Design and Optimal Nesting (스템핑 공정 최적화 시스템의 개발 : 최적블랭크 설계와 최적배치의 일체화)

  • 심현보;이상헌;박종규;김흥업
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • 한국소성가공학회 2003년도 춘계학술대회논문집
    • /
    • pp.283-287
    • /
    • 2003
  • In recent years, design of an optimal blank shape is very important for sheet metal forming process in the automobile industry because the raw material cost rate is significant part in the automobile industry. With the design of an optimal blank shape, the engineer can protect a blank from an excessive holding force to improve the quality and reduce the ratio of material scrap. Therefore design of an optimal blank shape is inevitable in sheet metal forming process. However, if it causes a complicated shape of blank, it may be difficult to do the blank layout optimally. In this study, we developed software of optimal blank layout connected with the software of optimal blank shape design which was created in the past by the present authors. And by using these softwares, we would like to present the method in order to get optimal utilization ratio easily and precisely within short time for the sequence of works from design to blank layout.

  • PDF

Disassembly Scheduling with Multiple Product Types and Parts Commonality (공통 부품을 포함한 복수 제품들에 대한 분해 일정계획)

  • Kim, Hwa-Joong;Lee, Dong-Ho;Xirouchakis, Paul
    • Proceedings of the Korean Operations and Management Science Society Conference
    • /
    • 대한산업공학회/한국경영과학회 2004년도 춘계공동학술대회 논문집
    • /
    • pp.421-424
    • /
    • 2004
  • This paper focuses on the problem of determining the quantity and timing of disassembling used products while satisfying the demand of their parts or components over a planning horizon. The case of multiple product types with parts commonality is considered for the objective of minimizing the sum of setup, disassembly operation, and inventory holding costs. A heuristic is suggested, in which an initial solution is obtained using a linear programming relaxation method, and then improved by perturbing the given solution using a dynamic programming approach and a look-ahead check while considering the trade-offs among different cost factors.

  • PDF

Buffer Sizing in FMS Environment through Transfer Pricing Mechanism (FMS 설비와 후속 생산설비의 내부거래 가격에 의한 완충 저장공간 결정)

  • Lee, Kyoung-Keun
    • Journal of Korean Institute of Industrial Engineers
    • /
    • 제16권2호
    • /
    • pp.81-89
    • /
    • 1990
  • Transfer pricing mechanism is applied to the problem of input buffer size in the context of interfacing a flexible manufacturing system with multiple following production lines. The size of the input buffers can be determined economically by using non-linear transfer pricing either in a decentralized organization or in a centralized organization. Under the certain conditions, input buffer size determined from this non-linear transfer pricing is more economical than the traditional economic lot size model. The benefit comes from transferring part of FMS' inventory to the following production lines. And this non-linear transfer pricing makes sense if the FMS' unit inventory holding cost is high enough.

  • PDF

Distribution Planning in a Multi-Echelon Inventory Model under Rolling Horizon Environment (Rolling Horizon 환경하에서 다단계 재고 모형의 분배계획 수립에 관한 연구)

  • Ahn, Jae-Sung;Kwon, Ick-Hyun;Kim, Sung-Shick
    • IE interfaces
    • /
    • 제16권4호
    • /
    • pp.441-449
    • /
    • 2003
  • In this paper we propose a distribution planning method aiming the use in the real-life situations. The assumed form of the distribution network is arborescence. At every node in the distribution network, orders are placed periodically. At each renewal of planning horizon, demand informations of periods in the horizon are updated. The objective of the problem is to minimize the total cost, which is the sum of holding and backorder costs of all sites during planning horizon. For such a situation, this study addressed an effective distribution plan when demands for demand-sites are provided for a given planning horizon.