Authors: Agostinho Agra, Catarina Avelino, Adelaide Cerveira, Alexandrino Delgado, Michael Poss
Addresses: Department of Mathematics and CIDMA, University of Aveiro, Campus Universitario de Santiago, 3810-193 Aveiro, Portugal. ' Department of Mathematics and CM-UTAD, Edificio de Ciencias Florestais, Quinta de Prados, University of Tras-os-Montes e Alto Douro, 5001-801 Vila Real, Portugal. ' Department of Mathematics, Edificio de Ciencias Florestais, Quinta de Prados, University of Tras-os-Montes e Alto Douro, 5001-801 Vila Real, Portugal. ' Department of Engineering Maritime Sciences, University of Cape Verde, CP 163, Ribeira de Juliao – Mindelo – Sao Vicente, Cape Verde. ' Computer Science Department, Boulevard du Triomphe CP 210/01, B-1050 Brussels, Belgium
Abstract: We consider a real production planning problem occurring in a glass container manufacturing company. The goal is to minimise the average stock level during a planning horizon of one year, maintaining customers satisfaction and keeping the production at its maximum rate. Besides the production capacity, the main constraints considered are related to the number of setup changes in machines, which is restricted in each factory. The main goal is to find the best balance between the number of setups and the average stock level. We propose a decomposition of the problem into two interrelated problems: a lot-sizing problem and a scheduling problem. For each problem we propose a mathematical model that can be solved using a commercial solver package. To be an efficient managerial tool, the method should provide quickly good solutions. Therefore we solve the lot-sizing problem through a relax-and-fix heuristic and discuss the results.
Keywords: lot sizing; scheduling; production planning; mixed integer programming; glass containers; glass container manufacturing; average stock levels; customer satisfaction; production capacity; setup changes; mathematical modelling.
International Journal of Mathematical Modelling and Numerical Optimisation, 2011 Vol.2 No.3, pp.253 - 272
Available online: 26 Jun 2011 *Full-text access for editors Access for subscribers Purchase this article Comment on this article