SOLVING A CONSTRAINED ECONOMIC LOT SIZE PROBLEM BY RANKING EFFICIENT PRODUCTION POLICIES

Abstract

We address the problem of finding the K best Zero-Inventory-Ordering (ZIO) policies of an Economic Lot-Sizing Problem (ELSP) with n time periods. To this end, we initially focus on devising an efficient algorithm to determine the Second Best ZIO policy. Based on both this latter algorithm and recent results from the state-of-the-art literature, we propose a solution method to compute the remaining K Best ZIO policies in O(n(K + n)) time and O(K+n2) space. One claimed advantage of this approach is that it would efficiently solve a family of ELS problems, which includes a basic knapsack type constraint. A computational experiment is carried out to test the performance of the new algorithm K-ZIO and Constrained-ZIO for different values of K and n. For the particular case when the left-hand side coefficients in that constraint are equal, we provide an O(n3) solution method.