W consider both branch-and-cut and column-generation approaches for the problem of finding a minimumcost assignment of jobs with release dates and deadlines to unrelated parallel machines. Results are presented for several variants both with and without constraint programming. Among the variants, the most effective strategy is to combine a tight and compact, but approximate, mixed integer progr...

In this work we study the unrelated parallel machines problem with the objective of the minimization of the maximum completion time or makespan (Cmax). We propose some metaheuristics based on a size-reduction of the original assignment problem. The idea is to consider only a few of the best possible machine assignments for the jobs and not all of them. We test the proposed simple algorithms wit...

This work deals with the problem of scheduling n independent jobs on m unrelated parallel machines with the objective of minimizing the makespan (the total elapsed time from the start of execution until all jobs have been completed). Preemption is not allowed. This way a job, once assigned to a particular machine, may not be removed until it has finished its execution. All the machines start wo...