هماهنگی در زنجیره تامین چند رده ای تحت عدم قطعیت عرضه و تقاضا

The main purpose of this paper is to study the inventory, production, and contracting decisions of a multi-echelon supply chain with both demand and supply uncertainty. We find that the commonly used wholesale price contracts used by both up-stream and downstream supply-chain members cannot coordinate the system. We then propose a returns policy used by the manufacturer and the retailer, combined with the wholesale price contract used by the raw-material supplier and the manufacturer, which can perfectly coordinate the supply chain. Through Nash bargaining analysis, we further provide contract terms that lead to win–win situation. We also investigate the impact of the supplier's risk attitude on the decisions, as well as the impact of spot market price for raw material on the performance of the entire supply chain.

This paper studies the supplier's raw-material production-planning decision, the retailer's replenishment decision, and the choice of contract for a three-tier supply chain with uncertainty about both demand and raw-material yield. The main purpose is to investigate contract terms that coordinate raw-material planning and replenishment decisions and achieve the most efficient performance of the entire supply chain. This paper differs from traditional random-yield and contracting papers in several ways: (1) Instead of focusing on a two-level supply chain that involves manufacturers and retailers, we study a three-level supply chain that includes a raw-material supplier that provides basic components and faces random yields, a manufacturer that is responsible for production, and a retailer that sells to the stochastic demand. Jaber and Goyal (2008) also consider channel coordination in a three-level supply chain; however, in contrast, they assume that both demand and supply are certain. (2) We also examine the contract terms (set by the supplier and the manufacturer respectively) in order to optimize the performance of the total supply chain. Most contract literature has focused on supply chain (systems) with perfect supply and on a two-level supply chain (Cachon, 2003). This paper examines the equilibrium inventory and supply decisions and contract decisions of the decentralized supply chain, and provides optimal contract prices that achieve the best performance of the supply chain with both yield and demand uncertainty. (3) We further investigate how a risk-averse supplier makes the production decision and compare it with that of a risk-natural supplier. To our knowledge, there is still no reference for the production-decision problem for a risk-averse supplier who faces supply uncertainty. Because of long lead times, complicated production processes, and unpredictable factors like weather and environment, the yield of a raw-material manufacturer is often lower than the initial production quantity. The central question of this paper is: what happens to a three-level supply chain that involves both demand and raw-material yield uncertainty? We consider a Stackelberg game in which the supplier plans production for raw materials by anticipating the retailer's order quantity and the realized yield follows a general probability distribution. What would the equilibrium order quantity and raw-material production quantity decisions be? Can simple wholesale-price contracts coordinate the three-level supply chain in the world of stochastic yields? How about the returns policy? To address these questions, we develop a single-period, one-supplier/one manufacturer/one-retailer supply-chain model that focuses on three major issues: replenishment, raw-material production planning, and contract prices for supply chains under both supply and demand uncertainty. In this model, the supplier and the manufacturer first propose contract terms for raw materials and finished products, respectively. The supplier is responsible for determining raw-material production quantity before the production season, and the retailer determines replenishment quantity before the demand is known. The manufacturer, which has deterministic yield, will purchase raw materials from the supplier at an amount that fulfils the retailer's order. In the case that the supplier does not yield enough raw materials to satisfy the manufacturer, it will purchase the difference from a spot market. The manufacturer then produces the same amount as the retailer's order quantity and the products are delivered to the retailer. Finally, demand is observed, revenues are collected, and profits are earned. This paper makes four main contributions. First, we provide insights for production, replenishment, and pricing decisions for a multi-echelon supply chain that involves both demand and supply uncertainty. We characterize the production decision of the supplier and the inventory replenishment decision of the retailer in such a system. Second, we investigate the efficiencies of wholesale price contracts and returns policy and provide contract terms that effectively coordinate the supply chain. We use Nash bargaining solution to provide contract terms that lead to a win–win situation. Third, we examine the impact of spot market on such a supply-chain system. We find that a high spot-market price for raw materials deteriorates the profit of the supply chain. In the extension, we investigate how a risk-averse and uncertain supplier makes the production decision, and we find that the more risk-averse the supplier is, the more the supplier plans to produce. The paper proceeds as follows. In Section 2, we discuss related literature and then in Section 3 we provide a description of the model, including notations and assumptions, and we study the integrated supply-chain problem. In Section 4, we investigate decentralized supply chain under wholesale price contracts, and in Section 5, we examine the decentralized supply-chain system where the manufacturer uses a returns policy instead of a wholesale price contract. Section 6 presents numerical examples to illustrate further insights. Section 7 extends the model to a risk-averse supplier and Section 8 presents conclusions, insights, and directions for future research.

This paper investigates the inventory decision of the retailer, raw-material planning decision of the supplier, and the optimal contracts for a three-tier supply chain with both demand and supply uncertainty. The key research question asks what contract format and contract parameters perfectly coordinate the supply chain and achieve a win–win situation. We first characterize the equilibrium decisions on inventory and production planning in the supply chain. We then found that the commonly used wholesale-price contracts cannot coordinate the supply chain. A properly designed returns policy between the manufacturer and the retailer, combined with a wholesale-price contract between the raw-material supplier and the manufacturer can efficiently coordinate the entire supply chain and achieve win–win outcome. This key result is consistent with the empirical observation that in supply chains with both raw-material supply and demand uncertainty, returns policies are widely used among downstream supply-chain members such as publishing and automobile industries. We also investigate how spot-market price and supply uncertainty for raw materials affect the performance of the supply chain. We found that a high spot-market price deteriorates the supply-chain profit. As an extension, we further explore the impact of risk-aversion of the raw-material supplier and we find that a risk-averse supplier tends to product more. Future research in this area is rich. One possibility is to investigate how multiple suppliers or multiple retailers affect the results of the paper. Competition from downstream or upstream might induce suppliers to produce more and retailers to order more, which might make it easier to coordinate the supply chain; however, a rigorous analysis is needed to draw a conclusion. Another possibility is to study and evaluate other contract formats, such as revenue sharing, channel rebate, or a quantity flexibility contract. The potential findings will provide guidance on how to better manage multi-echelon supply chains with both demand and supply uncertainty.