A tree search algorithm for the crew scheduling problem
نویسندگان
چکیده
In this paper we consider the crew scheduling program, that is the problem of assigning K crews to N tasks with fixed start and finish times such that each crew does not exceed a limit on the total time it can spend working. A zero-one integer linear programming formulation of the problem is given, which is then relaxed in a lagrangean way to provide a lower bound which is improved by subgradient optimisation. Finally a tree search procedure incorporating this lower bound is presented to solve the problem to optimality. Computational results are given for a number of randomly generated test problems involving between 50 and 500 tasks.
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