Sensitivity of production planning models and integration optimization role in minimizing tardiness

Abstract

Companies goal is keeping competitive and achieving significant profits by meeting all of their customers’ demands. For this sake, an effective production planning which is suitable for the company is required. In this context, we are interested by the integrated optimization of aggregate production planning and disaggregate production planning in order to guarantee feasibility and consistency across planning levels. The main contribution of this paper lies in using the integrated model’s output as an input to the scheduling model. Computational tests conducted first considering data from literature to mainly test the sensitivity of the three production planning models and then for the integrated model and the scheduling one. It was illustrated how each planning model is impacted by the parameter variations, emphasizing the integration’s robustness in preserving operational stability. Then, real data from a pharmaceutical company was used for only the integrated model and the scheduling one. It was shown how total weighted tardiness was minimized by 2 weeks compared to non integrated models. Finally, it should be mentioned that verification constraints established verification constraints between the two planning levels leads to a cost-effective solution for multi-product, multi-stage batch production environments.