Single machine scheduling to minimize weighted number of early jobs plus total weighted tardiness
摘要
The scheduling measure of minimum weighted number of early jobs has hardly been investigated by scheduling researchers. This note focuses on a single machine scheduling and due-date assignment problem with the objective function of minimizing the weighted number of early jobs plus total weighted tardiness (given a common due-date for all jobs). The problem is proved to be NP-hard, and based on a number of properties of an optimal schedule, a pseudo-polynomial dynamic programming algorithm is introduced. Based on our numerical tests, the proposed algorithm is efficient and practical: medium size problems (of up to 150 jobs) are solved in very reasonable running times.