Electric multiple unit circulation plan optimization based on the branch-and-price algorithm under different maintenance management schemes

PLoS One. 2018 Jul 6;13(7):e0199910. doi: 10.1371/journal.pone.0199910. eCollection 2018.

Abstract

For railway operators, one of many important goals is to improve the utilization efficiency of electric multiple units (EMUs). When operators design EMU circulation plans, EMU type restrictions are critical factors when assigning EMUs to the correct depots for maintenance. However, existing studies only consider that EMUs are maintained at their home depots. However, targeting that problem, in this paper, an optimization model for the EMU circulation planning problem that allows depots to be selected for EMU maintenance is proposed. This model aims at optimizing the number of used EMUs and the number of EMU maintenance tasks and simultaneously incorporates other important constraints, including type restrictions, on EMU maintenance and night accommodation capacity at depots. In order to solve the model, a branch-and-price algorithm is also developed. A case study of a real-world high-speed railway was conducted to compare and analyze the effects of different maintenance location constraints. The results show that the number of EMUs used will decrease under the maintenance sharing scheme, the number of EMU maintenance tasks can be reduced, and the time occupied in EMU maintenance will be released. In addition, the scheme of maintenance resources sharing and increases to mileage limits can effectively decrease the number of EMU maintenance tasks significantly. The model and algorithm can be used as an effective quantitative analysis tool for railway operators' decision-making processes in the EMU circulation planning problem.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Algorithms*
  • Commerce*
  • Electric Power Supplies / standards*
  • Humans
  • Maintenance / organization & administration*
  • Maintenance / standards*
  • Models, Theoretical
  • Records

Grants and funding

This research is jointly supported by the project entitled "EMU Circulation and Operation Plan for Optimizing the High Speed Railway" (grant no. 2013X014-C to L.N.), the National Natural Science Foundation of China (grant no. U1434207 to W.L.), the Science and Technology Department of the China Railway Corporation (grant no. 2011X014-E to L.N.), and Hebei Province University Science and Technology Research Project (grant no. QN2015154). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.