Conclusions and outlook

Integer linear programming, combined with a powerful solver such as Xpress-MP, can quickly lead to optimal or near-optimal solutions. Due to the large number of possible combinations between different billet lengths, it is impossible for the human planner to find optimal production/cutting plans in an acceptable time. In practice, the planner needs a few days to complete a sub-optimal plan, whereas the solver obtains optimal solutions in a matter of hours or even minutes. The solutions obtained by the solver are saved in a text file imported into Microsoft Excel for better presentation and to enable further analysis of the results.

In future research work, we would like to pursue two avenues of improvement. Firstly, we would like to optimize the modeling of the problem by perfecting the mathematical modeling. This can be achieved by better estimation of scrap costs...