A Cooperative Local Search Method for Solving the Traveling Tournament Problem

Constrained optimization is the process of optimizing a certain objective function subject to a set of constraints. The goal is not necessarily to find the global optimum. We try to explore the search space more efficiently in order to find a good approximate solution. The obtained solution should verify the hard constraints that are required to be satisfied. In this paper, we propose a cooperative search method that handles optimality and feasibility separately. We take the traveling tournament problem (TTP) as a case study to show the applicability of the proposed idea. TTP is the problem of scheduling a double round-robin tournament that satisfies a set of related constraints and minimizes the total distance traveled by the teams. The proposed method for TTP consists of two main steps. In the first step, we ignore the optimization criterion. We reduce the search only to feasible solutions satisfying the problem's constraints. For this purpose, we use constraints programming model to ensure the feasibility of solutions. In the second step, we propose a stochastic local search method to handle the optimization criterion and find a good approximate solution that verifies the hard constraints. The overall method is evaluated on benchmarks and compared with other well-known techniques for TTP. The computational results are promising and show the effectiveness of the proposed idea for TTP

La maîtrise d'urbanisation autour du champ gazier de Hassi R'mel: Algérie, entre réalité et action publique

Le présent article se situe à la croisée des deux thématiques: celle de la maitrise d’urbanisation et celle de la gouvernance environnementale, dans les sites urbanisés autour des industries gazières à risques majeurs. Notre choix s'est porté sur la ville de Hassi R’melAlgerie, située au sud algérien (520 Km au sud de la capitale) et abritant l'un des plus grands gisements gaziers du monde. Nous nous intéressons à mettre en lumière les stratégies de maitrise d’urbanisation à travers le processus d'exurbanisation en tant que projet pilote de la politique environnementale algérienne, en mettant l’accent sur le projet de relogement faisant parti des dix enjeux de l’exurbanisation et représentant le facteur premier de réussite ou d'échec de ce processus. Nous avons privilégié une approche comparative à la fois temporelle et spatiale basée sur le questionnaire et l'entretien directif. Nous avons ciblé un échantillon de 160 ménages résidents du bidonville de Hassi R’mel avant exurbanisation et 120 ménages parmi eux relogés dans la ville nouvelle de Bellil. Cette enquête a été complétée par des entretiens de type semi directif menés auprès de 22 acteurs locaux de l'opération urbaine. En analysant leurs réponses ainsi que les statistiques officielles, les résultats obtenus montrent une forte inadéquation de ces nouveaux lieux de résidence aux aspirations et au mode de vie des ménages notamment sur les plans socioculturel, spatial et environnemental.This paper is at the crossroads of the two themes: urban planning and environmental governance, in urban sites around major-risk gas industries. Our choice fell on the city of Hassi R'mel - Algeria, located in southern Algeria (520 km south of the capital) and home to one of the largest gas fields in the world. We are interested in highlighting the urbanization control strategies through the exurbanization process as a pilot project of the Algerian environmental policy, with a focus on the relocation project, which is one of the ten stakes of exurbanization and representing the primary factor of success or failure of this process. We favored a temporal and spatial comparative approach based on the questionnaire and the directive interview. We targeted a sample of 160 households residing in the slum of Hassi R'mel before exurbanization and 120 households among them relocated in the new city of Bellil. This survey was supplemented by semi-structured interviews conducted with 22 local urban operation actors. By analyzing their responses as well as official statistics, the results obtained show a strong inadequacy of these new places of residence to the aspirations and way of life of the households in particular at the sociocultural, spatial and environmental levels

La maîtrise d’urbanisation autour du champ gazier de Hassi R’mel – Algérie, entre réalité et action publique

The mastery of urbanization around the gas field of Hassi R'mel - Algeria, between reality and public action. This paper is at the crossroads of the two themes: urban planning and environmental governance, in urban sites around major-risk gas industries. Our choice fell on the city of Hassi R'mel - Algeria, located in southern Algeria (520 km south of the capital) and home to one of the largest gas fields in the world. We are interested in highlighting the urbanization control strategies through the exurbanization process as a pilot project of the Algerian environmental policy, with a focus on the relocation project, which is one of the ten stakes of exurbanization and representing the primary factor of success or failure of this process. We favored a temporal and spatial comparative approach based on the questionnaire and the directive interview. We targeted a sample of 160 households residing in the slum of Hassi R'mel before exurbanization and 120 households among them relocated in the new city of Bellil. This survey was supplemented by semi-structured interviews conducted with 22 local urban operation actors. By analyzing their responses as well as official statistics, the results obtained show a strong inadequacy of these new places of residence to the aspirations and way of life of the households in particular at the sociocultural, spatial and environmental levels