A hybrid heuristic for the multi-plant capacitated lot sizing problem with setup carry-over

Abstract

A hybrid heuristic for the multi-plant capacitated lot sizing problem with setup carry-over Journal of the Brazilian Computer Society, v.14, n.4, p.7-15, 2008 http://producao.usp.br/handle/BDPI/11832 Downloaded from: Biblioteca Digital da Produção Intelectual -BDPI, Universidade de São PauloBiblioteca Digital da Produção Intelectual -BDPI Departamento de Matemática Aplicada e Estatística -ICMC/SME Artigos e Materiais de Revistas Científicas -ICMC/SME NP-complete. There are many approaches for the CLSP with a single item, with multiple items and with only one or multiple production centers. Usually these problems are tackled heuristically [24,12,5], though exact solution methods exist to solve them [4], [19] and [2].The multi-plant capacitated lot sizing problem (MPCLSP) with multiple items and periods is composed of multiple production centers that produce all the same items as well as enabling transfers amongst the plants. Sambasivan and Schimidt [17] solved this problem with a heuristic based on transfers of production lots between the periods and the plants, while even better results were obtained by Sambasivan and Yahya [18] using a Lagrangian relaxation. Nevertheless, Nascimento et al. [14] introduced a GRASP (Greedy Randomized Adaptive Search Procedures) heuristic as well as a path relinking intensification procedure that outperformed the heuristic proposed in [18].There have been few studies on MPCLSP and no approach with setup carry-over was presented until now. The problem with setup carry-over considers two additional possibilities: to conserve the setup for one item along two consecutive periods, i.e., the setup carry-over occurs when the last item of a certain period is the first item to be produced in the next period; to allow using the idle capacity in one period in order to make the setup of the first item to be produced in the next period. Besides reducing setup cost, this strategy provides additional capacity with the lack of setup time between consecutive periods. As can be observed, it is necessary to judge which items are the first AbstractThis paper addresses the capacitated lot sizing problem (CLSP) with a single stage composed of multiple plants, items and periods with setup carry-over among the periods. The CLSP is well studied and many heuristics have been proposed to solve it. Nevertheless, few researches explored the multi-plant capacitated lot sizing problem (MPCLSP), which means that few solution methods were proposed to solve it. Furthermore, to our knowledge, no study of the MPCLSP with setup carry-over was found in the literature. This paper presents a mathematical model and a GRASP (Greedy Randomized Adaptive Search Procedure) with path relinking to the MPCLSP with setup carry-over. This solution method is an extension and adaptation of a previously adopted methodology without the setup carry-over. Computational tests showed that the improvement of the setup carry-over is significant in terms of the solution value with a low increase in computational time.

Fix-and-optimize heuristics for capacitated lot sizing with setup carryover and backordering

“…Almada-Lobo et al (2007) present two novel mixed integer programming (MIP) formulations for the real-world CLSP with setup carryover, sequence dependent setup times and costs in the glass container industry. A GRASP meta-heuristic is proposed in Nascimento and Toledo (2008) to solve the CLSP with setup carryover in a multi-plant setting. Another extension to this problem is to permit backordering of unsatisfied demand.…”

Adequando consultas por similaridade para reduzir a descontinuidade semântica na recuperação de imagens por conteúdo

“…O gapé o incremento de qualidade com relaçãoà estratégia de referência, assim, quanto maior o valor melhor o resultado. Essa medida de avaliação vem sendo utilizada em trabalhos relacionadosà otimização de problemas com complexidade de tempo polinomial ou NP que recorremà soluções heurísticas, como em [Nascimento e Toledo, 2008].…”