Local search algorithms, such as simulated annealing, tabu search, and local hill climbers attempt to optimize a solution to a problem by making locally improving modifications to a candidate solution. They rely on a neighborhood operator to restrict the search to a typically small set of possible successor states. The genetic algorithm mutation operator, likewise, enables the exploration of th...

The problem of finding a minimum vertex cover (MinVC) in a graph is a well known NP-hard problem with important applications. There has been much interest in developing heuristic algorithms for finding a “good” vertex cover in graphs. In practice, most heuristic algorithms for MinVC are based on the local search method. Previously, local search algorithms for MinVC have focused on solving acade...

Most global constraints maintain a support for their filtering algorithm, namely a tuple consistent with both the constraint and current domains. However, this highly valuable information is rarely used outside of the constraint. In this paper we define the TV-Break Packing problem (TVBP) and we propose a generic hybridization scheme that we test on this real-world application. The principle of...

The Walksat local search algorithm has previously been extended to handle quantification over variables. This greatly reduces model sizes, but in order to guide greedy moves the algorithm still maintains a set of violated clauses. For very large problems, or at the start of a search, this can cause memory problems. We design a new local search algorithm that does not maintain this set and is th...

We prove that the Bounded Occurrence Ordering k-CSP Problem is not approximation resistant. We give a very simple local search algorithm that always performs better than the random assignment algorithm (unless, the number of satisfied constraints does not depend on the ordering). Specifically, the expected value of the solution returned by the algorithm is at least Alg ≥ Avg+ α(B, k)(Opt −Avg),...

Guided Local Search is a general penalty-based optimisation method that sits on top of local search methods to help them escape local optimum. It has been applied to a variety of problems and demonstrated effective. The aim of this paper is not to produce further evidence that Guided Local Search is an effective algorithm, but to present an extension of Guided Local Search that potentially has ...

Extensive research has been devoted to economic production quantity (EPQ) problem. However, little atten-tion has been paid to problems where depreciation cost and process quality cost must be considered, simulta-neously. In this paper, we consider the economic production quantity model of minimizing the annual total cost subject to depreciation cost and process quality cost, where depreciation...