• Journal of Korean Institute of Industrial Engineers
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• v.32 no.4
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• pp.382-392
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• 2006

Vendor-managed inventory policy(VMIP) is a supply-chain initiative where the supplier is authorized to manage inventories of items at retail locations. In VMIP, the supplier monitors sales and stock information at retail locations and makes decisions of inventory replenishment and transportation simultaneously. VMIP has been known as an effective supply chain strategy that can realize many of benefits obtainable only in a fully integrated supply chain. However, VMIP does not always lead to lower the supply chain cost. It sometimes generates the total supply chain cost higher than the traditional retailer-managed inventory policy (RMIP). In this paper, we perform a comparison study on RMIP and VMIP in the retail supply chain which consists of a single supplier and a number of retailers. We formulate mixed integer programming models for both RMIP and VMIP with vehicle routing problems and perform computational experiments on various test problems. Furthermore, we derive the conditions which guarantee the dominant position for VMIP with respect to total supply chain cost in the simple retail supply chain.

• Journal of the Korean Operations Research and Management Science Society
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• v.26 no.3
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• pp.105-117
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• 2001

This paper models supply uncertainty in the dynamic Newsboy problem context. The system consists of one supplier and one retailer who places an order to the supplier every period to meet stochastic demand. Supply uncertainty is modeled as the uncertainty in quantities delivered by the supplier. That is, the supplier delivers exactly the amount ordered by the retailer with probability of $\beta$ and the amount minus K with probability of (1-$\beta$). We formulate the problem as a dynamic programming problem and prove that retailer’s optimal replenishment policy is a stationary base-stock policy. Through a numerical study, we found that the cost increase due to supply uncertainty is significant and that the costs increase more rapidly as supply uncertainty increases. We also identified the effects of various system parameters. One of the interesting results is that as retailer’s demand uncertainty, the other uncertainty in our model, increases, the cost increase due to supply uncertainty becomes less significant.

• Journal of the Korean Operations Research and Management Science Society
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• v.37 no.3
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• pp.117-134
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• 2012

We analyze a systematic relationship between transaction mechanisms and wholesale pricing schemes within a supply-chain with two competing suppliers and a monopolistic retailor. When one of the suppliers changes its transaction mechanism from an independent scheme to a cooperative one, then the wholesale prices of the suppliers become cheaper than before. When one supplier changes its transaction scheme to a cooperative one while the other supplier sticks to the existing independent transaction scheme, we show that the supplier with a cooperative transaction scheme can realize the increased profit via a profit sharing contract with the retailer but the supplier with independent transaction scheme can face the decreased profit. We also show that both suppliers can achieve the higher profits by adopting the cooperative schemes with the retailer.

• The Journal of Industrial Distribution & Business
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• v.14 no.9
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• pp.21-30
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• 2023

Purpose: Focusing on the role of the special contract to collaborate the supply chain operations, this study investigates how the revenue sharing contract affects the performance of Vendor Managed Inventory (VMI). Research design, data, and methodology: The optimization model is formulated to represent two stage supply chain system where the supplier and retailer manage the operations to maximize their own profits. Three supply chain models including the traditional system, VMI, and VMI with revenue sharing contract are compared in the numerical examples. Results: According to the numerical analysis, the entire supply chain system has greater profit under VMI than the traditional system, while VMI alone sacrifices the supplier's profit. With the proper sets of revenue share ratio and wholesale price discount rate, VMI with revenue sharing contract results in the increased profit for both supplier and retailer compared with VMI alone as well as the traditional system. Conclusions: The numerical examples imply that VMI, when it is combined with the revenue sharing contract, can be the effective collaboration program that satisfies every supply chain member. To make VMI with revenue sharing contract to be fair to all supply chain members, they need to agree on the appropriate contract content.

• Journal of the Korea Society for Simulation
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• v.31 no.1
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• pp.19-27
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• 2022

This study compares and analyzes wholesale(or price-only) contract, revenue-sharing contract, quantity-flexibility contract, and channel-rebate contract in a decentralized supply chain consisting of one supplier and one retailer. By setting the parameters of each coordination contract based on the previous results, we conduct simulations using @RISK for several combinations of these parameters. Under the supply chain coordination, we evaluate the probability of successfully signing a contract and the participant in favor of each contract. As a result, the quantity-flexibility contracts is most advantageous for the retailer and the channel-rebate contracts is most advantageous for the supplier. It revealed that revenue-sharing contracts can be used more flexibly because they can be selected in the widest range to redistribute profits between supplier and retailer.

• Journal of the Korean Operations Research and Management Science Society
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• v.41 no.2
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• pp.101-127
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• 2016

Irrational ordering decisions of supply chain members have been gaining growing importance in the area of supply chain management. Irrational ordering behaviors that deviate from the profit maximizing decisions in the newsvendor settings have observed with human experiments in recent research. These behaviors can be modeled with several typical decision bias elements. This bias in ordering decisions affects the performance of supply chain contracts designed based on the assumption that the supply chain members make optimal decisions, making it necessary to design supply chain contracts by considering the irrationality. The purpose of this research is to derive a method to design the revenue sharing contract that considers human irrationality in ordering decisions. This research considers a simple two-echelon supply chain consisting of one supplier and one retailer, where the supplier is assumed to be perfectly rational while the retailer making newsvendor type ordering decisions displays irrational ordering behaviors. Under this environment, this research analytically models the revenue sharing contract to maximize the total supply chain profit or the supplier's own profits while considering the three decision bias patterns of the retailer, which include the pull-to-center effect, the prospect theory, and the increased subjective sensitivity to the revenue sharing ratio. Irrationality parameters are measured through human experiments based on which and through numerical simulations, we showed that significant improvements in the supply chain performance can be achieved.

• Journal of the Korean Operations Research and Management Science Society
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• v.37 no.1
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• pp.45-59
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• 2012

We analyze a transaction mechanism so-called the revenue sharing transaction model and its dynamics in a supply chain with two competing suppliers and a monopolistic retailer when the demand pattern is uncertain and the back-order is allowed in case. We assume that the products by the suppliers are substitutable each other with a certain degree even though their retail prices are different. It is proved that a supplier and the retailer in the supply chain have some room for enjoying the possibility of their increased profits comparing with the present ones by adopting the suggested revenue sharing scheme. Furthermore, such a transaction model is beneficial even to the customers by offering a lower retail price than before. On the contrary, we observe that another supplier which sticks to an existing transaction scheme is supposed to suffer some decrease in its profit as a result.

• Journal of the Korean Operations Research and Management Science Society
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• v.30 no.3
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• pp.81-93
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• 2005

This paper models supply chain uncertainties in the dynamic Newsboy Problem context. The system consists of one supplier and one retailer who place an order to the supplier every period. Demand uncertainty is modeled as stochastic period demand, and supply uncertainty as the uncertainty in quantities delivered by the supplier. The supplier delivers exactly the amount ordered by the retailer with probability of $\beta$ and the amount minus K with probability of $(1-\beta)$ We formulate the problem as a dynamic programming problem and derive the first-order optimality condition. Through a numerical study, we measure the extent to which the cost decrease due to the reduction in supply uncertainty depends on the level of demand uncertainty. One of the most important findings In this paper is that this cost decrease is relatively small if demand uncertainty is kept high, and vice versa. We also backup this numerical result by analyzing the distribution of ending Inventory under the supply and demand uncertainties.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.05a
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• pp.179-186
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• 2006

There was a lot of research to integration of the transshipment and inventory problem in supply chain. Such a integration of inventory and transshipment problem called IRP (Inventory Routing Problem). We consider a distribution problem in which a set of products has to be shipped from a supplier to several retailers in a given planning horizon. Transshipment from the supplier to the retailer is performed by vehicles of limited capacity. Each retailer determines replenishment leadtime and order quantity with buffer management. A supplier determines optimal vehicle routing in supply chain. We suggest a heuristic algorithm which be used TOC buffer management in a replenishment problem and a tabu search algorithm in VRP (Vehicle Routing Problem).

• Journal of the Korean Operations Research and Management Science Society
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• v.30 no.3
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• pp.17-39
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• 2005

The coordination of a three-level supply chain consisting of a supplier, a retailer, and a discount outlet (DCO) is studied here. We assume that the product is sold in two consecutive periods a Normal Sales Period (NSP) and a subsequent Clearance Salvage Period (CSP). A benchmark case is studied Initially in which the supply chain is coordinated by a s1n91e agent. Thus, the supplier the retailer, and the discount outlet design a common system that allows centralized decision making about stocking quantities, markdown time schedules, and policies on disposing of leftovers to deliver the greatest possible expected supply chain profit. Next, we consider a decentralized supply chain. Here, decisions are made without coordination. The objective is to maximize an individual party's expected profits. The focus of the study is on the following questions: what factors make the coordination an effective approach for the supply chain? How do we coordinate the supply chain so as to maximize the supply chain Joint expected profit? These and other related study issues are explored in this paper.