[论文解读] Mathematical Model of Optimal Empty Rail Car Distribution at Railway Transport Nodes

Aleksandr Rakhmangulov, A.D. Kolga+3 more|arXiv (Cornell University)|May 10, 2015

Transport and Logistics Innovations参考文献 4被引用 10

一句话总结

本文提出了一种混合整数线性规划（MILP）模型，用于优化铁路运输节点的空车调配，整合了车务单位、车站容量及图定列车的约束。该模型在OJSC '马格尼托戈尔斯克冶金联合企业' 实施后，通过在尊重运营和所有权要求的前提下，高效地将空车分配至装车点，显著减少了调度员的规划时间和空车停留总时长。

ABSTRACT

At present there are two trends in the market of rail freight transportation in Russia: freight owners put forward higher demands to the transportation quality (promptness of delivery) in an effort to reduce storage costs by means of reducing the size of freight shipment; the structure of railcar traffic volume of the railways of Russia is getting more complex due to the reduction of the average shipment size and due to the transfer of railcar fleet ownership to a large number of operating companies. These trends significantly complicate operational management supervision of railway stations and transport nodes. Application of typical data from the information system about the railcar location at the transportation node is not enough for the dispatchers to make the best decision concerning the car traffic management. The article is concerned with the description and development of the mathematical model of empty railcar distribution for loading at the railway transport node; this model will take into account the requirements of railcar owners in terms of their cars application, the operating work level of railroad stations of the transportation node and the possibility of adding the groups of empty railcars to the transfer trains, clean-up trains and industrial railway trains operating on a tight schedule. The developed model and the software package were implemented in the information system of the industrial railway of the major metallurgical enterprise - OJSC "Magnitogorsk Metallurgical Works", which processes up to two thousand of railcars belonging to different owners. This model made it possible to reduce the labour intensity of dispatcher operation planning the empty railcar distribution for loading and reduce the total time the railcars spend in the enterprise railway system.

研究动机与目标

• 解决由于货物批量减小和车务单位分散导致的铁路货运运营复杂性增加的问题。
• 通过引入运营和所有权约束，超越基础位置数据，提升调度员决策质量。
• 构建数学模型，支持在考虑图定列车和车站工作负荷的前提下，实现最优空车调配。
• 降低调度作业的劳动强度，以及空车在企业铁路系统内停留的总时长。

提出的方法

• 构建混合整数线性规划（MILP）模型，以优化运输节点的空车分配。
• 纳入车务单位对车辆使用和所有权权利的相关约束。
• 对车站运营能力和工作负荷进行建模，防止调度资源过载。
• 整合将空车组加入图定中转、清理及工业列车的可能性。
• 利用软件包将模型嵌入一家大型冶金企业的信息系统中。
• 基于OJSC '马格尼托戈尔斯克冶金联合企业' 的真实数据验证模型，处理来自多个车务单位的最多2,000辆空车。

实验结果

研究问题

• RQ1 在来自多个车务单位的复杂约束和图定列车运行的条件下，如何优化空车调配？
• RQ2 何种数学建模方式可实现空车的高效分配，同时满足车站容量和运营工作负荷的限制？
• RQ3 集中式优化模型在多大程度上可减少工业铁路网络中调度员的规划工作量和空车停留时间？
• RQ4 将图定列车运行（如中转、清理、工业列车）整合进模型，如何提升空车调配效率？
• RQ5 在实际工业铁路系统中，基于模型的方法是否能在时间与劳动效率方面优于传统调度方法？

主要发现

• 模型成功降低了冶金企业在规划空车调配过程中调度员作业的劳动强度。
• 模型实施后，空车在企业铁路系统内的总停留时间显著减少。
• 该模型实现了空车组与图定列车（包括中转、清理及工业列车）的高效协同。
• 基于该模型的软件包已成功集成至OJSC '马格尼托戈尔斯克冶金联合企业' 的现有信息系统中。
• 模型可处理来自不同车务单位的最多2,000辆空车，证明了其在复杂、多车务单位环境下的可扩展性。
• 该解决方案通过将空车调配与所有权规则及严格的调度约束相协调，显著提升了运营效率。