In this work, a new robust nonlinear controller is presented in presence of large external disturbances for a quadrotor aircraft. The controller is based on an improved sliding mode control. The improvement is done by adding two other terms, one is a backstepping synthesis and the other one is a fuzzy logic term in order to reduce the chattering phenomenon and achieve more acceptable performance. The dynamical motion equations are obtained by Euler-Newton formalism. Lyapunov theorem is used to prove the stability of control system. A simulation is carried out to illustrate the effectiveness of the proposed control.

The basin of Timgad belongs to the North-Eastern Algerian Saharan Atlas; it is located at the northern extension of the Aures Mountains. The basin is an asymmetrical syncline oriented East-West covering an area of 1000 Km2. The climate is semi-arid (cold winter and hot summer) with average annual rainfall not exceeding 400 mm. Recently, the increasing agricultural activities led to an excessive exploitation of groundwater resources. In order to meet this rising water supply demands, implementing a water resources management policy is a priority which should be based on a basin hydrogeological study. Effectively, the geological and geophysical studies have confirmed the presence of permeable Miocene and Cretaceous formations (sandstone and carbonate); relatively resistant affected by fractures network, which are probably forming a confined aquifers. Indeed, recent wells drilled in the basin center and their boundaries; show that the aquifers are artesian. The sandstone aquifer of the Miocene is the most important, it is characterized by significant thickness which can exceed 200m, its extension as well as its particular corrugated geometry, characterized by a wavy shape, which forming a series of shale-marl filling depressions, influences the groundwater flow, actually, the piezometric surface illustrates groundwater convergent flow oriented to the east, towards Bou el freis, likewise the sandstone aquifer is marked by the presence of a West-East drainage axis which separates the basin northern part characterized by a low reservoirs hydraulic capacity from the southern part distinguished by the groundwater relative abundance. Groundwater is generally easily extracted, except the northern part of the basin where the top shale-marl layer is thickens to over 1000m.

Le lot sizing et l’ordonnancement sont deux problèmes applicables dans différents domaines, en particulier dans le secteur industriel. Ils sont généralement effectués de manière séquentielle, ce qui génère des coûts élevés ou des conflits d'infaisabilité. En outre, la résolution de ces problèmes d’une manière intégrée, dans les systèmes de fabrication complexes, est très difficile. L'objectif principal de cette thèse serait de développer des approches de résolution pour le problème intégré de planification et d'ordonnancement dans les ateliers de type flow-shop. Dans ce travail, le cas plus simple du flow-shop qui a une structure particulière, devrait pouvoir être exploitée pour concevoir de nouvelles méthodes de résolution ou adapter les méthodes proposées dans des travaux précédents. Le cas de fabrication ou de chaîne logistique à plusieurs niveaux pourrait aussi être étudié dans cette thèse

The purpose of this study was to establish a method based on an iterative scheme to approximate the numerical solution obtained from finite elements analysis for an RVE in two and three dimensions based on the homogenization concept for the assessment of the effective properties. The bounds of Hashin–Shtrikman and Voigt–Reuss were considered in the iterative process based on an updating of the constitutive relations of these models respectively. In this study, by assumption, we took the particular case of the heterogeneous materials with several elastic isotopic phases. The output variables considered using the iterative process are the bulk, shear modulus and the thermal conductivity. We have found a fast convergence of the iterative solution to the numerical result with a suitable concordance between the two solutions at the final step.