ABSTRACT

This work focuses on freight consolidation in multimodal rail and road transportation. The transportation network comprises of a centralized source warehouse, a set of destination warehouses, and intermediate transshipment terminals. The paper formulates a single period integer programming model and a multi-period constraint programming model for optimizing multimodal freight transportation with volume discount on rail freight rate. The first model is aimed at consignee organizations with comparatively low shipment quantity and less frequent transportation, while the second model targets organizations which require continuous freight transportation on a massive scale. The single-period model is solved using a commercially available CPLEX solver. However, due to the computational complexity of the multi-period constraint programming model, a heuristic named Rail and Truck Allocation Algorithm (RATAA) is proposed. Computational experiments are carried out to prove the efficiency of the proposed solution approaches.

摘要

这项工作集中于多式联运铁路和公路运输中的货运合并。运输网络包括一个集中的源仓库，一组目标仓库和中间转运码头。提出了单周期整数规划模型和多周期约束规划模型，以优化铁路货运费率的多式联运。第一个模型针对的是发货量相对较低且运输频率较低的收货人组织，而第二个模型针对的是需要大规模连续货运的组织。单周期模型使用市售的CPLEX求解器求解。但是，由于多周期约束规划模型的计算复杂性，提出了一种启发式的铁路和卡车分配算法（RATAA）。进行了计算实验，以证明所提出的解决方案方法的效率。