att_abstract={{The set multicovering or set K-covering problem is an extension of the
classical set covering problem, in which each object is required to be
covered at least K times. The problem finds applications in the design
of  communication networks and in computational biology. We describe a
GRASP with path-relinking heuristic for the set K-covering problem,
as well as the template  of a family of Lagrangean heuristics. The
hybrid GRASP  Lagrangean heuristic employs the GRASP with path-relinking
heuristic using modified costs to obtain solutions for the Lagrangean
relaxation problem. Computational experiments carried out on 135 test
instances show experimentally that the Lagrangean heuristics performed
consistently better than GRASP.  By properly tuning the parameters
of the GRASP Lagrangean heuristic, it is possible to obtain a good
trade-off between  solution quality and running times. Furthermore, the
GRASP Lagrangean heuristic makes better use of the dual information
provided by subgradient optimization and is able to discover better
solutions and to escape from locally optimal solutions even after the
stabilization of the lower bounds, when other strategies fail to find
new improving solutions.
	att_categories={C_CCF.1, C_CCF.2, C_CCF.7, C_CCF.8},
	att_copyright_notice={{The definitive version was published in Computers & Operations Research (Elsevier). {{, 2011-12-31}}{{, http://www.sciencedirect.com/science/article/pii/S0305054811003431}}}},
	att_tags={GRASP,  hybrid heuristics,  metaheuristics,  path-relinking,  Lagrangean relaxation,  Lagrangean heuristics,  local search,  set covering,  set multicovering,  set K-covering},
	author={Mauricio Resende and Luciana S. Pessoa, Fed. U. of R. Grande do Norte and Celso C. Ribeiro, Fed. Fluminense U.},
	institution={{Computers & Operations Research}},
	title={{A hybrid Lagrangean heuristic with GRASP and path-relinking for set K-covering