2010 Volume 61 Issue 1 Pages 11-16
In this research, a production/delivery scheduling problem of minimizing the total flow time and the number of deliveries is considered. A job with a different processing time and due date is processed with one machine. There is a trade-off relationship between the total flow time and the number of deliveries. The production/delivery scheduling problem is formulized as large-scale combinatorial optimization problems. Therefore, the production/delivery scheduling problem required development of an efficient enumeration algorithm, in order to search for the Pareto-optimal solution. In this paper, we propose an algorithm which reduces the enumeration of due-date delay or non-inferior production schedule by using the due-date restriction and SPT (Shortest Processing Time) constraint. Moreover, a delivery scheduling problem is divided into a partial problem by due-date restrictions. An algorithm which reduces the enumeration of a delivery schedule is proposed by sequentially merging the Pareto solution of a partial problem. The efficiency of the proposed algorithm is investigated using a 20 jobs problem.