In this article we investigate the application of iterated local search (ILS) to the single machine total weighted tardiness problem. Our research is inspired by the recently proposed iterated dynasearch approach, which was shown to be a very effective ILS algorithm for this problem. In this paper we systematically configure an ILS algorithms by optimizing the single procedures part of ILS and ...

In this paper, we study the perturbation operator of Iterated Local Search. To guide more efficiently the search to move towards new promising regions of the search space, we introduce a Critical ElementGuided Perturbation strategy (CEGP). This perturbation approach consists of the identification of critical elements and then focusing on these critical elements within the perturbation operator....

In this paper the linear ordering problem with cumulative costs is approached. The best known algorithm solution for the problem is the tabu search proposed by Duarte. In this work an experimental study was performed to evaluate the intensification and diversification balance between these phases. The results show that the heuristic construction phase has a major impact on the tabu search algor...

This paper presents a simple iterated local search metaheuristic incorporating a k-opt local search (KLS), called Iterated KLS (IKLS for short), for solving the maximum clique problem (MCP). IKLS consists of three components: LocalSearch at which KLS is used, a Kick called LEC-Kick that escapes from local optima, and Restart that occasionally diversifies the search by moving to other points in ...

We investigate some ways in which massively parallel computing devices can be exploited in local search algorithms. We show that the substantial speed-ups that can be gained from parallel neighbourhood evaluation enables an efficient best improvement local search, and that this in turn enables further speed-ups through selection and parallel application of a set of independent, improving moves....

This paper analyzes the detection of stagnation states in iterated local search algorithms. This is done considering elements such as the population size, the length of the encoding and the number of observed non-improving iterations. This analysis isolates the features of the target problem within one parameter for which three different estimations are given: two static a priori estimations an...

A practical nurse rostering problem, which arises at a ward of an Italian hospital, is considered. The nurse rostering problem is a typical employee timetabling problem, where each month it is required to generate the nursing staff shifts subject to various contractual and operational requirements. These requirements may be in conflict especially for those months in which manpower is reduced du...

This paper presents three techniques for using an iterated local search algorithm to improve the performance of a state-of-the-art branch and bound algorithm for job shop scheduling. We use iterated local search to obtain (i) sharpened upper bounds, (ii) an improved branchordering heuristic, and (iii) and improved variableselection heuristic. On randomly-generated instances, our hybrid of itera...

Graph coloring is a well known problem from graph theory that, when attacking it with local search algorithms, is typically treated as a series of constraint satisfaction problems: for a given number of colors one has to find a feasible coloring; once such a coloring is found, the number of colors is decreased and the local search starts again. Here we explore the application of Iterated Local ...

Abstract Electric buses (eBuses) will be the mainstream in mass urban transportation near future. Thus, installing charging infrastructure convenient locations play a critical role transition to eBuses. Taking this into account, paper we propose an iterated local search algorithm optimize location of stations while satisfying certain properties system, e.g., demand and ensuring that limited dri...