IMPROVING CROSS DOCKING SYSTEMS BY ENABLING LOAD INTEGRATION

In order to reduce costs and increase the efficiency of the supply chain system, cross docking is one of the most important warehousing management strategies for combining products from different providers to different customers. Products in inbound trucks are gathered from suppliers and then are passed through customers using outbound trucks through the cross docking. Cross docking is one of the innovative product distribution strategies to minimize unnecessary inventory and improve the customer service level. Truck scheduling plays an important role in cross docking system. Cross docking works best for companies that distribute large volumes of merchandise and/or operate a large number of stores. Cross docking systems handle a large number of items in a short amount of time. The advantages of cross docking systems include increased inventory turnover, thus reduced inventory, increased customer responsiveness, and better control of the distribution operation. In this study, a special state of cross docking is considered in which inbound truck can also be used as outbound truck. The advantages of this state are reduced loading, unloading time, and reduced vehicle costs. To investigate this problem, the developed mathematical model was used to obtain the appropriate solution to solve the mathematical model and to determine the validity and accuracy of the modeling using optimization software such as GAMS and MATLAB. At small sizes to which optimization software can find the optimal solution, GAMS optimization software was used to solve the mathematical model. For medium and large sizes where optimization software cannot find the optimal solution, MATLAB software and ALO, Memetic, and ACOR algorithms were used to solve the mathematical model and the efficiency of this algorithm was tested to solve such problems. The results showed that the feasibility of the proposed approach and demonstrated good performance of the ALO algorithm in solving this problem.