A hybrid VNS algorithm for solving the multi-level capacitated minimum spanning tree problem

• Published in: Electronic notes in discrete mathematics Vol. 66; pp. 159 - 166
• Main Authors: Campos, J.C.T., Martins, A.X., Souza, M.J.F.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-04-2018
• Subjects: Combinatorial Optimization; Multi-level capacitated minimum spanning tree; Neighborhood structures; Variable Neighborhood Search; Combinatorial Optimization; Neighborhood structures; Variable Neighborhood Search; Multi-level capacitated minimum spanning tree
• ISSN: 1571-0653; 1571-0653
• DOI: 10.1016/j.endm.2018.03.021

This work addresses the multi-level capacitated minimum spanning tree (MLCMST) problem. It consists of finding a minimal cost spanning tree such that the flow to be transferred from a central node (root) to the other nodes is bounded by the edge capacities. In this paper, a hybrid algorithm, combining the Variable Neighborhood Search (VNS) metaheuristic and one mathematical programming formulation of the literature, is used for solving it. The formulation is used to give an initial solution to VNS. Five neighborhoods are used for exploring the solution space. Results show that the VNS is able to improve the initial solutions and to obtain small gap solutions for all instance sets.