Single machine scheduling with due dates and class setups

Standard scheduling problems bear the assumption that each job has a constant setup time and thus this setup time can be included in the processing time of a job. However, many realistic production systems suggest otherwise. This paper considers a single machine scheduling problem where jobs are classified into classes and a setup is required between jobs of different classes, but not between jobs of the same class. This class setup time depends only on the current job, not on the previous job. The performance measure is the maximum lateness of jobs. Several properties of the optimal solution and a lower bound of the optimal lateness are developed to construct a branch-and-bound algorithm in the search of an optimal schedule and the effectiveness of the proposed algorithm is empirically evaluated.