Mehdi EL KRARI

British Antarctic Survey | BAS · BAS Research Centre

Fitness functions fail to differentiate between different solutions with the same fitness, and this lack of ability to distinguish between solutions can have a detrimental effect on the search process. We investigate, for the Travelling Salesman Problem (TSP), the impact of using a hash function to differentiate solutions during the search process....

The generalized travelling salesman problem (GTSP) is a variant of the well-known travelling salesman problem. The cities are in this case spread into clusters and only one city from each one must be visited to make a cyclic tour with a minimal cost. Following this assumption, an instance can be subject to dimensionality reduction since removing so...

The Traveling Salesman Problem (TSP) is one of the most popular Combinatorial Optimization Problem. It is well solicited for the large variety of applications that it can solve, but also for its difficulty to find optimal solutions. One of the variants of the TSP is the Generalized TSP (GTSP), where the TSP is considered as a special case which mak...

The Travelling Salesman Problem (TSP) is one of the most popular Combinatorial Optimization Problem. It is well solicited for the large variety of applications that it can solve, but also for its difficulty to find optimal solutions. One of the variants of the TSP is the Generalized TSP (GTSP), where the TSP is considered as a special case which ma...

Local Optima Networks are models proposed to understand the structure and properties of combinatorial landscapes. The fitness landscape is explored as a graph whose nodes represent the local optima (or basins of attraction) and edges represent the connectivity between them. In this paper, we use this representation to study a combinatorial optimisa...

The travelling salesman problem (TSP), a famous NP-hard combinatorial optimisation problem (COP), consists of finding a minimum length tour that visits n cities exactly once and comes back to the starting city. This paper presents a resolution of the TSP using the breakout local search metaheuristic algorithm (BLS), which is based on the iterated l...

The Generalized Traveling Salesman Problem (GTSP) is a Combinatorial Optimization Problem considered as a generalization of the well known Traveling Salesman Problem. The GTSP, which is an NP-Hard problem, consists of visiting only one city/node from each region/cluster from all given clusters of an instance. This paper introduces a new reduction m...

We propose in this paper a novel idea to handle a tour for the Generalized Traveling Salesman Problem (GTSP), which is an NP-hard optimization problem very solicited for its numerous applications. Knowing that for each instance, cities are grouped in clusters. The proposed method finds for each one its barycenter in order to get in a first phase a...

This paper proposes a detailed study of the Multi-Fragment (MF) tour construction (TC) algorithm for the Travelling Salesman Problem (TSP). This TC heuristic is based on an edge selection strategy which favors edges with the smallest cost under the constraint to have a feasible tour. Extensive computational experiments have been performed on benchm...