Supply Delay Ordering Policy For Perishable Product

With the development of economic and the progress of science and technology, the supply-demand relationship has transformed from a seller's to a buyer's market, customers'demand have become more individual and diverse, product life cycles have been shortened. More and more commodities have been with perishable characteristic. Regarding to the highly uncertainty demand in the supply chain of perishable goods, many papers have suggested that contracts can reduce the influence of uncertainty demand. One of the most common contracts is buy-back contract. However, supply uncertainty has become to a major topic in recent years. Machine breakdown, natural disasters and social problems, which have been result suppliers failed to arrange production or transportation as planned. Especially, with economic globalization, more and more corporations purchase raw material or organize production in the global range, which increase the length of transform distance and lead time. The supply become more uncertainty. Delay is one kind of common supply uncertainty.Considering supply delay, will the buy-back contract still coordinate the supply chain? One contribution of our paper is to study the retailer's ordering policies under the buy-back contract, considering the demand distribution influenced by delay and the unreliable supplier pay some compensation for delay. Another contribution is to investigate the optimal ordering policy in a dual-supplier system with minimum lot size under delay.The main conclusions are as follows.In the first topic, we consider the retailer's ordering policies under two kinds of compensation. The results indicate the following effects of delay: when the unreliable supplier pays unit fine, the retailer's optimal ordering quantity and the expected profits are not monotonic in the probability of delay. When the unreliable supplier shares the retailer's loss, the optimal ordering quantity and the retailer's expected profit are decreasing in the probability of delay, and increasing in the ratio of sharing the loss.In the second topic, we investigate the coordination with buy-back contract under delay. Its shows that the buy-back contract can coordinate the supply chain, and the buy-back price under coordination is decreasing in the probability of delay and the unit fine(or the ratio of sharing the loss). Considering coordination, when the unreliable supplier pays unit fine, the supplier prefers a strategy with high buy-back price and small unit fine, but the retailer prefers an opposite strategy, both the supplier and the retailer are willing to sharing the risk of uncertain demand and unwillingness in sharing the risk of delay. However, when the unreliable supplier shares the retailer's loss, the retailer's expected loss is interrelated with the demand distribution, and there's a case in which both the retailer and the supplier are willing to share the risk of delay.Finally, this paper investigates the optimal ordering policy in a dual-supplier system with minimum lot size under delay. The discussion shows that the optimal total order quantity and expected profit under delay are decreasing in the probability of delay. The order quantity booking to reliable supplier is increasing in the unreliable supplier's probability of delay. The upper limit of the reliable supplier'minimum lot size that the retailer can accept is increasing in the possibility of delay, while the unreliable supplier's is decreasing.