Study On Collaborative Procurement And Cost Allocation Problems With Perishable Products

Due to the highly perishable nature and customers’special preferences of some products, such as fresh fruits, fresh vegetables, live seafood, we should transfer these products from the field to the table in the shortest possible time to maintain high food quality and reduce the losses. Since our country lacks cold storage, sophisticated transportation facilities and is backward in fresh-keeping technique, fresh products in process of circulation can cause even greater losses. In recent years, with economy developing and living standard improved, the demand for perishable products is on the decrease, with much higher requirement for the quality, the diversity, and the freshness. Implementing supply chain management has great significance for modern enterprise to reduce logistics costs and guarantee food safety. Therefore, with the fruit chain store and big chain superstores as the research project, this thesis studies the joint replenishment problem and cost allocation problem for multi-retailers when they form a purchasing alliance.Firstly, inventory control model and cost allocation game under the finite replenishment rate are established when the retailers place their ordering simultaneously. It is proved that the optimal ordering policy exists, and the core of the cost allocation game is nonempty. The efficiency of several proportional rules is also studied by simulation. Based on this analysis, collaborative procurement problem when the retailers store their goods jointly in the storehouse with lowest holding cost is studied. The conclusion implies that the alliance’s cost under centralized storage is lower than that under independent storage. Moreover, the inventory game with shortage and backlogging is considered. It is proved that the optimal ordering policy exists, and the proportional rule lies in the core. The property for proportional solution rules on the class of ordering cost games is also studied.Secondly, the jointly replenishment problem for multi-retailers under the permissible delay of payments offered by the supplier is studied. When all the retailers have only one type of customers, the optimal ordering policy and the cost allocation problem are studied. The effects of credit terms and deterioration rates on the retailer’s cost are also discussed. When all the retailers have two types of customers, the alliance’s cost is less than the sum of retailer’s cost when they order independently. The proportional allocation rule is defined and proved to be a core allocation. In addition, the effect of the final customer’s rate on the retailer’s cost is analyzed emphatically.Thirdly, inventory models of multi-product under two different ordering policies are developed. When the demand for all the types of product is not equal to zero, ordering every product jointly may be a choice for the alliance. The grand coalition under the given proportional allocation rule lies in the largest consistent set. Therefore, the grand coalition is a stable outcome not only from the myopic point of view of stability but also from the farsighted point of view of stability. If there exists a retailer whose demand for some types of product is zero, the best ordering policy is ordering each product independently. Under this policy, the optimal ordering policy and the cost allocation problem are studied for each product. There exist lower bound and upper bound for each retailer’s expected cost sharing. Based on this analysis, a distribution model for the retailers that lie in the line is developed. Only in some cases, the retailer’s cooperation is meaningful, and the retailer near to the supplier prefers to the marginal vector solution, while the retailer located away from the supplier prefers to the proportional allocation rule.Finally, the jointly replenishment problem for multi-retailers with quantity discount is studied. In the context of the supplier maximizing his profit, the optimal quantity discount contract exists when the retailers order independently and order jointly. The collaborative procurement not only leads to a decrease in each retailer’s cost but also improves the supplier’s profit. Moreover, if there exists cost coordination among retailer’s in ordering jointly, it is proved that retailer’s cooperation is meaningful in some circumstances.This study enriches the inventory model with perishable products, and extends the theory and method of cooperative game. The results give a theoretical basis and reference for collaborative procurement and cost allocation problems in supply chains with perishable products.