Computing Optimal Lot Sizes in the Economic Lot Scheduling Problem

This paper treats a version of the Economic Lot Scheduling Problem (ELSP) in which items may be produced several times in different amounts during a cycle. We show how to compute the optimal lot sizes and cycle length, given the sequence of items in a cycle. This requires solving a parametric quadratic program, plus a few EOQ calculations. Our procedure is designed to be used along with a heuristic for selecting the sequence of items in a cycle, such as the one proposed in 1987 by G. Dobson. The two algorithms together comprise a simple, plausible heuristic for the ELSP as a whole.