A Multi-level Memetic/Exact Hybrid Algorithm for the Still Life Problem

نویسندگان

  • José E. Gallardo
  • Carlos Cotta
  • Antonio J. Fernández
چکیده

Bucket elimination (BE) is an exact technique based on variable elimination. It has been recently used with encouraging results as a mechanism for recombining solutions in a memetic algorithm (MA) for the still life problem, a hard constraint optimization problem based on Conway’s game of life. This paper studies expanded multi-level models in which this exact/metaheuristic hybrid is further hybridized with branch-and-bound techniques. A novel variable clustering based recombination operator is also explored, with the aim of reducing the inherent time complexity of BE. Multi-parent recombination issues are analyzed as well. The obtained results are of higher quality than any previous metaheuristic approach, with large instances being solved to optimality.

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تاریخ انتشار 2006