Descent methods for combinatorial optimization proceed by performing a sequence of local changes on an initial solution which improve each time the value of an objective function until a local optimum is found. Several metaheuristics have been proposed which extend in various ways this scheme and avoid being trapped in local optima. For example, Hansen and Mladenovic have recently proposed the ...

Maximum clique is one of the most studied NP-hard optimization problem on graphs because of its simplicity and its numerous applications. A basic variable neighborhood search heuristic for maximum clique that combines greedy with the simplicial vertex test in its descent step is proposed and tested on standard test problems from the literature. Despite its simplicity, the proposed heuristic out...

Heuristics based on large neighborhood search have recently shown outstanding results in solving various transportation and scheduling problems. Large neighborhood search methods explore a complex neighborhood by use of heuristics. Using large neighborhoods makes it possible to find better candidate solutions in each iteration and hence traverse a more promising search path. Starting from the l...

The generalized minimum spanning tree problem is a generalization of the minimum spanning tree problem. This network design problems finds several practical applications, especially when one considers the design of a large-capacity backbone network connecting several individual networks. In this paper we study the performance of six neighborhood search heuristics based on tabu search and variab...

The p-center problem is a well-known and highly studied pertaining to the identification of p potential n center locations in such way as minimize maximum distance between users closest center. As opposed p-center, p-second minimizes sum distances from second centers. In this paper, we propose new Variable Neighborhood Search based algorithm for solving problem. Its performance assessed on benc...

Several problems are emerging in the context of communication networks and most them must be solved reduced computing time since they affect to critical tasks. In this research, monitor placement problem is tackled. This tries cover communications an entire network by locating a specific nodes network, such way that every link remains surveyed. case solution cannot generated allowed time, penal...

Given an undirected graph with weights associated with its edges, the degree-constrained minimum spanning tree problem consists in nding a minimum spanning tree of the given graph, subject to constraints on node degrees. We propose a variable neighborhood search heuristic for the degree-constrained minimum spanning tree problem, based on a dynamic neighborhood model and using a variable neighbo...