  A high-speed train needs high-level maintenance when its accumulated running
mileage or time reaches predefined threshold. The date of delivering an
Electric Multiple Unit (EMU) train to maintenance ranges within a time window
rather than be a fixed date. Obviously, changing the delivering date always
means a different impact on the supply of EMU trains and operation cost.
Therefore, the delivering plan has the potential to be optimized. This paper
formulates the EMU train high-level maintenance planning problem as a
non-linear 0-1 programming model. The model aims at minimizing the mileage loss
of all EMU trains with the consideration of the maintenance capacity of the
workshop and maintenance ratio at different times. The number of trains under
maintenance not only depends on the current maintenance plan, but also
influenced by the trains whose maintenance time span from the last planning
horizon to current horizon. A state function is established to describe whether
a train is under maintenance. By using this function the constraint of
restricting the total number of trains that are under maintenance can be
formulated reasonably well. Finally, a simulated annealing algorithm is
proposed for solving the problem.
