A bilevel decomposition approach to railway crew rostering problems for fair labor condition

The railway crew rostering problem is a scheduling problem to find a set of rosters that is feasible assignment of crew duties satisfying several labor conditions. We propose a novel decomposition approach to solve railway crew rostering problems with the objective of fair labor condition in order to reduce the computational effort. The upper level master problem determines an assignment of crew duties to the set of rosters and the lower level subproblem generates a feasible sequence of rosters including several labor conditions. The effective cuts are proposed to reduce feasible search space to tighten the duality gap between solutions of two level problems. Computational results demonstrate the effectiveness of the proposed method compared with that of the constraint programming technique.