In this article we investigate a new variant of Variable Neighborhood Search (VNS): Relaxation Guided Variable Neighborhood Search. It is based on the general VNS scheme and a new Variable Neighborhood Descent (VND) algorithm. The ordering of the neighborhood structures in this VND is determined dynamically by solving relaxations of them. The objective values of these relaxations are used as in...

The course timetabling problem is one of the most difficult combinatorial problems, it requires the assignment of a fixed number of subjects into a number of time slots minimizing the number of student conflicts. This article presents a comparison between state-of-the-art hyper-heuristics and a newly proposed iterated variable neighborhood descent algorithm when solving the course timetabling p...

Driven by new laws and regulations concerning the emission of greenhouse gases, carriers are starting to use battery electric vehicles (BEVs) for last-mile deliveries. The limited battery capacities of BEVs necessitate visits to recharging stations during delivery tours of industry-typical length, which have to be considered in the route planning in order to avoid inefficient vehicle routes wit...

This paper is concerned with the development of a new hybrid metaheuristic approach for solving a practical university course timetabling problem in Vietnam. Our hybrid method is a combination of Harmony Search (HS) algorithm and the Bees algorithm. The proposed method has been tested on 14 real-world data instances and compared with some other metaheurisitic approaches, which are Variable Neig...

Local genetic algorithms have been designed with the aim of providing effective intensification. One of their most outstanding features is that they may help classical local search-based metaheuristics to improve their behavior. This paper focuses on experimentally investigating the role of a recent approach, the binary-coded local genetic algorithm (BLGA), as context-independent local search o...

We consider the generalized minimum edge-biconnected network problem where the nodes of a graph are partitioned into clusters and exactly one node from each cluster is required to be connected in an edge-biconnected way. Instances of this problem appear, for example, in the design of survivable backbone networks. We present different variants of a variable neighborhood search approach that util...

Given an undirected graph with prizes associated with its nodes and weights associated with its edges, the prize-collecting Steiner tree problem consists in finding a subtree of this graph which minimizes the sum of the weights of its edges plus the prizes of the nodes not spanned. In this paper, we describe a multi-start local search algorithm for the prize-collecting Steiner tree problem, bas...

In this study, we improved the variable neighborhood search (VNS) algorithm for solving uncapacitated multilevel lot-sizing (MLLS) problems. The improvement is two-fold. First, we developed an effective local search method known as the Ancestors Depth-first Traversal Search (ADTS), which can be embedded in the VNS to significantly improve the solution quality. Second, we proposed a common and e...

We present a hybrid method to efficiently solve Google Machine Reassignment problem (MRP), the problem proposed at ROADEF/EURO Challenge 2012 competition. We study, implement, combine and empirically examine different local search neighborhoods to solve the set of available instances. Intensification and diversification of search is achieved through the suitable change of the objective function...

Abstract—This paper aims to present non-population search algorithms called tabu search (TS), simulated annealing (SA) and variable neighborhood search (VNS) to minimize the total cost of capacitated MRP problem in multi-stage assembly flow shop with two alternative machines. There are three main steps for the algorithm. Firstly, an initial sequence of orders is constructed by a simple due date...