The Setup Carryover Assignment Problem

In this paper, we introduce the Setup Carryover Assignment Problem (SCAP), which consists of determining the setup carryover plan of multiple items for a given lot size over a finite planning horizon with the objective of maximizing setup cost savings. This problem is an extension of the standard Capacitated Lot Sizing Problem (CLSP). We show that the straightforward linear programming (LP) formulation of the problem provides a fractional solution. However, we propose an alternative integer linear program (ILP) and show that it has a totally unimodular property and thus yields an integer solution. Therefore, SCAP is solvable in polynomial time.