Pepin, A.S.

solution heuristic vehicle problem depot schedule column instance generation method search value mdvsp column generation heuristic approach lagrangian algorithm scheduling iteration network master problem number constraint result variable parameter 1500- task instances k ∈ k column generation location quality solution process strategy subproblem research master vehicle schedules model neighborhood lagrangian heuristic column generation method operations research integer quality solutions procedure process column generation approach solution times programming operation metaheuristic science subgradient task i fi rst time windows soumi depot k branch-and-cut r schedules relaxation structure neighborhood search heuristic objective formulation connection solution quality schedule selection strategy tabu search heuristic column generation process desaulnier 1500- transportation vehicle k table pull-in arc solution values transit depot k k sched