A branch and bound approach for earliness-tardiness scheduling problems with different due dates
Abstract
The problem of scheduling n jobs on a single machine in order to minimize the weighted sum of earliness and tardiness in NP-complete when jobs have different due dates. In most of the papers dedicated to this problem, authors assume that there is no idle time between two consecutive jobs. However, as indicated by several authors, this assumption is not consistent with the earliness-tardiness criterion. It is the reason why we do not make this assumption in this paper. To reach an optimal solution, we propose a branch-and-bound approach which takes advantage of some dominance properties and lower bounding procedures. Numerical experiments show that the algorithm can solve this problem with up to twenty jobs in a reasonable amont of time.