Joint Replenishment of Perishable Items with Partial Backorder by Considering Direct and Indirect Grouping Approaches

: Appropriate management of inventory control system of perishable items plays an important role in organizations' total cost due to short life cycle and perishability of the items. An inventory control system includes the allocation of orders to suppliers, identification of inventory levels and coordination of orders. This paper proposes mathematical models in the multi-supplier joint replenishment problem of perishable items with partial backorder by considering direct and indirect grouping approaches. In direct grouping approach, all the items in a group are ordered at the same time while in indirect grouping approach each item is ordered in an integer multiple of a base cycle time. Taylor's expansion is used to achieve a polynomial approximation for the model. The two approaches are compared through a numerical example. Based on the results, the two approached create relatively similar solutions. The sensitivity analysis of the numerical example shows that an increase in perishability parameter, makes the model to increase the ratio of backordered demands and decreases the total sale. In addition, an increase in major ordering cost leads to increase in cycle times and total purchasing quantities

Keywords:

joint replenishment , perishable items , direct grouping , indirect grouping , partial backorder