A NOVEL META-HEURISTIC BASED METHOD FOR SCHEDULING VEHICLES IN CROSS DOCKING PROBLEMS

Cross docking is a product-handling and distribution concept in which product items are sorted out and rec ognized based on customer demands and move directly from the receiving dock to shipping dock, without being held as inventory in the warehouse. Cross docking systems can decrease the storage and products retrieval costs in comparison with traditional warehouses by synchronizing the ows of inbound and outbound trucks. Generally,crossdockingisagoodstrategyforcompanies that distribute large volume of products and/or serve a large number of stores. Cross docking facilities include four main functions of warehousing. These four major functions are receiving, storage, order picking, and shipping. Among these four functions, storage and order picking are typically the most costly. Storage function is costly because of inventory holding costs. On the other hand, order picking is expensive because it needs labour work. Cross docking minimizes the storage and order picking functions of a warehousewhileitstillallowsreceivingandshippingthe product items. Thispaperproposesanovelmeta-heuristicbasedmethod for scheduling vehicles in cross docking problems with considering temporary storage. In other words, products can be stored in a temporary storage and wait for loading in an outbound truck. The objective of the proposed method of this paper is to minimize makespan. Makespan in this study is dened as the total operating time of the cross docking operation. The makespan covers the interval between the moment of unloading the rst product from an inbound truck into receiving dock and the moment of loading the last product into shipping truck. In order to evaluate the performance of the proposed method, dierent problems are provided and analyzed. Moreover, the proposed method of this paper is compared to a well-known method of literature. The computation results reveal that the proposed method of this paper outperforms the compared method.