Comparison the metaheuristic simulated annealing and integer linear programming for solving the forest harvest scheduling with adjacency constraints/Comparacao entre a meta-heuristica simulated annealing e a programacao linear inteira no agendamento da colheita florestal com restricoes de adjacencia

• Published in: Ciência florestal 2013-04, Vol.23 (2), p.449
• Main Authors: Gomide, Lucas Rezende, Arce, Julio Eduardo, da Silva, Arinei Carlos Lindbeck
• Format: Article
• Language: Spanish
• Subjects: Forest management; Reforestation
• ISSN: 1980-5098

The impacts on the landscape after forest harvesting in reforestation are visible, but the cutting is a necessary process to ensure a sustained yield and introduce new technologies. An alternative of control is to use the adjacency constraints in the mathematical models. Thus, the aim of the study was to assess the ability of the metaheuristic SA to solve mathematical models with adjacency constraints type URM, and to check its action with the increasing of the problem complexity. The study was conducted in a forest project containing 52 stands, and created 8 scenarios, where the Johnson and Scheurmann (1977) model I was used as reference. The adjacency constraint type URM was used to control the cutting of adjacent stands. The models were solved by the ILP and metaheuristic SA, which was sued 100 times per scenario. The results showed that the scenario 8 has consumed 137,530 seconds via PLI, which represented 2,023.09 times more than the average time processing of the SA metaheuristic (67.98 seconds). The best solutions were 4.71% (scenario 1) to 11.40% (scenario 8) far from the optimal (ILP). The metaheuristic SA is capable to solve the forest problem, meeting the targets in the most cases. The increasing of complexity produced a higher deviation from the optimal. Concludes that the metaheuristic SA should not be processed a single time, because there are hazards in obtain inferior solutions, but doing it is recommended to increase the stop criterion. Keywords: artificial intelligence; integer linear programming; forest harvest. Os impactos gerados na paisagem apos a colheita florestal em reflorestamentos sao visiveis, porem, o corte raso e um processo necessario para garantir uma producao sustentada e introduzir novas tecnologias. Uma alternativa de controle e utilizar restricoes de adjacencia nos modelos matematicos. Assim, o objetivo do estudo foi avaliar a capacidade da meta-heuristica SA na resolucao de modelos matematicos com restricoes de adjacencia do tipo URM, e observar sua acao com o aumento da complexidade do problema. O estudo foi conduzido em um projeto florestal contendo 52 talhoes, sendo criados 8 cenarios, onde o modelo I de Johnson e Scheurmann (1977) foi usado como referencia. A restricao de adjacencia do tipo URM foi usada para controlar o corte de talhoes adjacentes. Os modelos foram resolvidos pela PLI e meta-heuristica SA, no qual foi processada 100 vezes/cenario. Os resultados mostraram que o cenario 8 consumiu 137.530 segundos vi