On multi-item economic lot-sizing with remanufacturing and uncapacitated production

In this study, we consider the multi-item economic lot-sizing problem with remanufacturing and uncapacitated production. By observing that the problem comprises several independent single-item problems, we show how very high quality feasible solutions and bounds can be obtained by solving each item separately using an effective recently proposed approach. Computational experiments demonstrate that our approach improves the best known feasible solutions and lower bounds for all the available instances. In addition, we show that 86 instances can be solved to optimality and the remaining open gap is below 0.5% for almost all the unsolved instances.