在满足用户需求约束下合理选择运输方式是物流管理的一个核心问题。结合各种运输方式的技术经济特点,以实现时效性物流整体费用最小化为目的,建立了在时间和容量约束下的多式联运方式选择的0-1整数规划模型,该模型在多节点、多种运输方式的情况下是NP—Complete问题,常规算法难以求解,故设计遗传算法予以求解。算例显示,通过联合运输的方式可以从整体上达到物流最优,不仅可以实现物流的实效性,也可以降低物流成本。
How to choose transportation mode in intermodal is a key problem to transport logistics under the constraint of consumer's demand. In order to minimize logistics cost, a 0-1 integral model is established in this papor to investigate mode choice of freight transportation constrained by time and capacity. Because the problem is an NP-complete problem with the increment of transport nodes and modes, which cannot be resolved by the common methods, genetic algorithm is designed to solve this problem in this paper. A numerical exampie indicate that the logistics process can be optimized by intermodal transport, not only consumer's time demand can be fulfilled, but also logistics cost can be reduced.