Research Article A Heuristic Approach for Determining Lot Sizes and Schedules Using Power-of-Two Policy

We consider the problem of determining realistic and easy-to-schedule lot sizes in a mul-tiproduct, multistage manufacturing environment. We concentrate on a specific type of production, namely, flow shop type production. The model developed consists of two parts, lot sizing problem and scheduling problem. In lot sizing problem, we employ bi-nary integer programming and determine reorder intervals for each product using power-of-two policy. In the second part, using the results obtained of the lot sizing problem, we employ mixed integer programming to determine schedules for a multiproduct, multi-stage case with multiple machines in each stage. Finally, we provide a numerical example and compare the results with similar methods found in practice. Copyright © 2007 E. Ekinci and A. M. Ornek. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, dis-tribution, and reproduction in any medium, provided the original work is properly cited. 1. Background and motivation In practice, companies basically use single-stage models in order to find easy answers for production lot sizing and scheduling problem ignoring the multistage characteristic