Fix-and-Optimize Heuristic and MP-based Approaches for Capacitated Lot Sizing Problem with Setup Carryover, Setup Splitting and Backlogging.
Published in 2015 The 6th International Workshop on Lot Sizing, Montréal, Canada, 2015
Abstract: In this paper, we focus on the single-level, multi-item capacitated lot sizing problem with setup carryover, setup splitting and backlogging. Although the capacitated lot sizing has been investigated with many different features from researchers, the simultaneous consideration of setup carryover and setup splitting is relatively new. This consideration is beneficial to reduce costs and produce feasible production schedule. In this research, we use a simple plant location reformulation of the original mixed integer programming model to obtain a tighter relaxation. We also add valid inequalities to further tighten the formulation. A fix-and-optimize heuristic with two-step product decomposition and period decomposition strategy is proposed to solve the formulation. The computational results show the effectiveness of the approach, achieving 6% and 8% average optimality gap of data with and without backlogging, respectively.