The Optimization Study Of Empty Container Allocation In Inland Multiple Depots System

In recent years, the liner transportation of container in the global got rapid development. The industry of container liner transport is a big investment, high risk of capital intensive industry. With the development of container ship’s large-scale, rapidness, specialization, container transport costs are also constantly improved, and in all kinds of transportation costs, container fees after port disbursement, ranks second. Because of the imbalance in international trade, some countries or regions have idled empty containers, and other countries or regions lack of empty containers at the same time, each year because of the empty container transportation cost is considerable. So in order to reduce the empty container transportation costs, maximize economic benefits, we should try to configure the minimum quantity of containers, for this it requests that we must rent containers, make containers, allocate containers and repair containers reasonably.Because of the imbalance of supply and demand of containers, shipping companies need to dispatching empty containers regularly between ports or yards. This article is mainly study an inland depot system of a port, and research how to dispatching empty containers to demand customer of empty containers excellently. At the same time we considered two different modes of transportation between the nodes where dispatching empty containers, namely, road and rail. In this paper, there is a method of dispatching empty containers to meet the demand of empty container customers that it can dispatch empty containers from inland depots or port, if this method can’t fully meet the demand of empty container customer, we consider the immediate leasing of container, the insufficient part can be supplemented at any time by leasing. Inventory restrictions of both the depots and port, and transport capacity constraints of different modes of transportation between different nodes are considered.The objective function is to minimize the sum total cost of the transportation cost, the storage cost and the leasing cost in a planning period. And we establish an optimization model of integer programming. Finally the numerical example is solved by using Lingo software, and the results were analyzed, and concluded that how to dispatch the empty containers from when, where and by which mode of transportation to provide the required quantity of empty containers to empty container demand customers, so as to be able to achieve optimal objective function and found the best scheduling scheme.The consequence proved the feasibility and effectiveness of the construction of optimization model,and theory instruction significance for the dispatching optimization scheme of empty containers in the inland depot system.