Minimizing the total completion time in single-machine scheduling with step-deteriorating jobs

In this paper, we study a scheduling problem of minimizing the total completion time on a single machine where the processing time of a job is a step function of its starting time and a due date that is common to all jobs. This problem has been shown to be NP-hard in the literature. To derive optimal solutions from a practical aspect, we develop a lower bound and two elimination rules to design branch-and-bound algorithms. Through computational experiments, we show that the proposed properties are e2ective in curtailing unnecessary explorations during the solution-3nding process, and that the synergy of these properties can solve problems with up to 100 jobs in a few seconds. ? 2003 Elsevier Ltd. All rights reserved.