As a key operation for the daily maintenance of electric multiple units (EMU), the first-level maintenance operation directly affects the utilization efficiency of the EMU. The fixed operation sequence of EMU trains, the limitation of the track capacity and inconsistent arrival time of EMU trains give rise to such problems as extended waiting time, idle tracks and waste of maintenance capacity. To solve these problems and optimize the assignment of EMU-to-track, we propose a flexible job-shop sequence scheduling (Flexible-JSS) mode for the first-level maintenance of EMU trains, and a flexible sequence and tracks sharing (FSTS) model for the first-level maintenance at electric multiple units depot (EMUD) has also been proposed in this paper. The FSTS model is designed to shorten the latest completion time after taking into account the constraints such as the train length, track capacity, the operation sequence of all EMU trains, the operation process of a single EMU train, and the train-set scheduling plan. A modified genetic algorithm is used to solve the model. The feasibility and effectiveness of the model and algorithm are verified by a real case, and the comparison with the other two fixed job-shop sequence scheduling (Fixed-JSS) modes proves that the Flexible-JSS mode can improve the efficiency and ability of the first-level maintenance at EMUD impressively.

中文翻译：

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动车组列车一级维修运行优化模型与算法

作为动车组日常维护的关键作业，一级维护作业直接影响动车组的利用效率。动车组列车运行顺序固定，轨道容量有限，动车组列车到站时间不一致，导致等待时间延长、轨道闲置、维修能力浪费等问题。为了解决这些问题并优化动车组到轨道的分配，我们提出了一种灵活的作业车间序列调度（Flexible-JSS）模式用于动车组列车的一级维护，以及灵活的序列和轨道共享（FSTS）本文还提出了电动车组（EMUD）一级维修模型。FSTS模型在考虑列车长度、轨道容量、所有动车组列车的运行顺序、单列动车组列车的运行过程、列车编组调度计划等约束条件后，缩短最晚完成时间. 使用改进的遗传算法来求解模型。通过一个真实案例验证了模型和算法的可行性和有效性，并与另外两种固定作业车间顺序调度（Fixed-JSS）模式的比较证明了Flexible-JSS模式能够提高调度的效率和能力。 EMUD 的一级维护令人印象深刻。