LAUSR

In this study, the problem of electric multiple unit (EMU) circulation planning and train timetabling is studied through a coordinated process that provides a feedback mechanism to simultaneously minimise the number of EMUs, the number of EMU maintenance tasks and the train travel time. Based on an adjustable train departure time window as the key parameter in the problem, the approach mainly consists of two components: a column generation process, which searches for better EMU circulation routes; and a mathematical model, which produces timetables. These components interact according to the results of computational assessments until the solution reaches a certain level of optimality or the allotted computation time is exhausted. Finally, the authors test this approach using a small example to illustrate the effectiveness, and they also study a real-world case. A quantitative comparative analysis shows that long travel distances and travel times of trains significantly affect the number of EMUs used. The results indicate that the proposed model and algorithm can effectively address the coordinated optimisation problem of integrating EMU circulation planning and timetabling.