摘要

An Economic Lot-sizing(ELS) problem with perishable inventory has been studied extensively over the years and plays a fundamental role in the inventory management. In this paper, we consider the problem where backlogging is allowed with the general economies of scale cost functions. Since the special case without backlogging is NP-hard, the considered problem is also NP-hard. The main contributions of this paper is to explore the properties of the optimal solution and propose an approximation solution with the cost no more than 4 root 2+5/7 times the optimal cost. Our results generalize a study on an ELS model for perishable inventory but without backlogging.