Lagrangean Relaxation with Clusters for the Uncapacitated Facility Location Problem

نویسندگان

  • Francisco de Assis Corrêa
  • Luiz Antonio Nogueira Lorena
  • Edson Luiz França Senne
چکیده

A good strategy for the solution of a large-scale problem is its division into small ones. In this context, this work explores the lagrangean relaxation with clusters (LagClus) that can be applied to combinatorial problems modeled by conflict graphs. By partitioning and removing the edges that connect the clusters of vertices, the conflict graph is divided in subgraphs with the same characteristics of the whole problem. When relaxing the removed edges in the lagrangean way, subproblems are solved and better limits than the traditional lagrangean relaxation are obtained. This work applies the LagClus to the Uncapacitated Facility Location Problem (UFLP).

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تاریخ انتشار 2006