Shunting Engine Scheduling at Railway Technical Stations with Time Window, Waiting Cost and Outfit Considerations

This paper studied the shunting engine scheduling at a railway technical station with considerations of both shunting tasks (including break-up, make-up, and pick-up and delivery tasks) and non-shunting tasks (including shift, and meal tasks), time windows of non-shunting tasks, and waiting cost and outfit requirements of engines. Given the set of shunting engines and that of shunting tasks in the planning horizon, this problem lay in assigning a sequence of shunting tasks and determining the start time of shift, meal and outfit tasks (if any) for each engine. A connection network was constructed for each engine to describe its time-space utilization process of executing shunting/non-shunting tasks and connections between tasks. By utilizing the modeling framework for the node-arc model of the multi-commodity network flow problem, the problem was formulated into a mixed integer nonlinear programming model with the objective of minimizing the sum of total deadheading cost, total wheel stop waiting cost, total deviation penalty cost of non-shunting tasks and total outfit cost. The model was further transformed into a linear model, which can be solved quickly to op-timality by invoking commercial solvers. Finally, computational experiments on a realistic instance constructed based on a station were conducted to validate the feasibility and efficiency of the proposed approach. © 2024 Science Press. All rights reserved.