Multi-Stage Opportunistic Maintenance Decision-Making for Electric Multiple Unit Systems with Bi-Objective Optimization

In order to improve operation efficiency of the electric multiple unit when running reliably, a multi-stage opportunistic maintenance decision strategy with bi-objective optimization is proposed based on the traditional opportunistic maintenance strategy. The window of opportunistic maintenance is equidistantly divided into multiple stages, and components located at different stages are maintained by different efforts. Aimed to solve problem of assigning multiple maintenance tasks of components, an assignment algorithm with two repairpersons is proposed. To further improve the multi-attribute optimization performance of this model, the proposed algorithm is introduced into the multi-attribute decision-making. The numerical example analysis verifies the effectiveness of the multi-stage opportunistic maintenance strategy in optimizing availability and average cost rate. Furthermore, the influence of weight factors on optimization tendency is discussed as well.