Perishable Product Inventory Policy Research

The classic strategy of perishable product inventory supposes that the demand is a random variable. In this paper we suppose the demands are fuzzy variables, fuzzy random variable and random fuzzy variable respectively, then we use the credibility theory to analyze the research questions. There are three main parts:In the case of demand being fuzzy variable, we first create a single node in the discrete fuzzy demand perishable product inventory cost and profit model. Then we got their expectations by credibility measure of fuzzy events. Through the analysis of the expectations of the model we found the contact with discrete random demand model. We also establish a continuous fuzzy demand model for single-node perishable product inventory cost and profit models, credibility theory has been using to get their expectations models and prove that the sum of expected cost and profit is the market average profit. Furthermore we give the condition of optimality order quantity, and compared with the continuous random demand model. Finally a supply chain system with single manufacturer and single retailer whose demand is continuous fuzzy variables is studied. Using credibility theory, we obtained the retailer's optimal order quantity, then discuss the cooperation and non-cooperation strategy respectively about the supply chain profit, the study found in the cooperative strategy will be more profitable in the supply chain than non-cooperative.In the case of demand being fuzzy random variables, and the fuzzy random cost and profit model, the two single-cycle supply chain's manufacturers, retailers and supply chain profit model are established respectively. Using credibility theory, we got the expectation of fuzzy random profit and cost model function. Based on the nature of expectations of the function, the optimality order conditions of single-node and the optimal order quantity of the retailer of the supply chain is given. Meanwhile we also discuss the profits of retailer, manufacturer and the whole supply chain in the cooperation and non-cooperative strategies respectively, the results show that supply chain will be more profitable if we chose cooperation strategy.In the case of demand being random fuzzy variables, we first presented the profit and cost models of a single node perishable product inventory policy. The expected profit and cost model is obtained by credibility theory; then through analyzing the relationship between the profit and cost expectations, we obtain the optimality conditions for minimum cost and maximum profit. Furthermore we established the manufacturer's, retailer's and the whole supply chain profit models respectively. Using credibility theory, we found that the supply chain under centralized decision the profit is greater than the supply chain under decentralized decision. Paid by a linear transfer contract, the supply chain under decentralized decision-making is also to achieve the perfect coordination.