In this paper we propose a Deep Reinforcement Learning approach to solve a multimodal transportation planning problem, in which containers must be assigned to a truck or to trains that will transport them to their destination. While traditional planning methods work "offline" (i.e., they take decisions for a batch of containers before the transportation starts), the proposed approach is "online", in that it can take decisions for individual containers, while transportation is being executed. Planning transportation online helps to effectively respond to unforeseen events that may affect the original transportation plan, thus supporting companies in lowering transportation costs. We implemented different container selection heuristics within the proposed Deep Reinforcement Learning algorithm and we evaluated its performance for each heuristic using data that simulate a realistic scenario, designed on the basis of a real case study at a logistics company. The experimental results revealed that the proposed method was able to learn effective patterns of container assignment. It outperformed tested competitors in terms of total transportation costs and utilization of train capacity by 20.48% to 55.32% for the cost and by 7.51% to 20.54% for the capacity. Furthermore, it obtained results within 2.7% for the cost and 0.72% for the capacity of the optimal solution generated by an Integer Linear Programming solver in an offline setting.
翻译:在本文中,我们提出“深加学习”办法,以解决多式联运规划问题,其中集装箱必须分配到卡车或火车上,将集装箱运到目的地。传统规划方法“脱线”(即在运输开始之前对一批集装箱作出决定),而拟议方法则是“在线”办法,因为可以在运输过程中就单个集装箱作出决定。规划在线运输有助于有效应对可能影响最初运输计划的意外事件,从而支持公司降低运输费用。我们在拟议的深加学习算法中采用了不同的集装箱选择超常,我们利用模拟现实情景的数据,在物流公司进行实际案例研究的基础上,评估了每种超常的性能。实验结果表明,拟议方法能够了解有效的集装箱派任模式,在运输总成本和使用火车能力方面超过经过测试的竞争者20.48%至55.32%,在成本方面超过55.52%至20.54%。此外,我们在拟议的深加学习算法中采用了不同的集装箱选择超常率。此外,我们利用模拟现实情景的数据,根据物流公司的实际案例研究设计,评估了每个超常性性能。实验结果表明,拟议的方法在运输总成本方面比20.48%至55.32%不等,在成本为55.54%到20.54%至20.54%之间,在能力上取得了结果,在2.7%,在平线上,在确定最佳解决方案。