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Meknes, Morocco

Shtessel Y.,University of Alabama in Huntsville | Taleb M.,Ecole Centrale Nantes | Taleb M.,Moulay Ismai University | Plestan F.,Ecole Centrale Nantes
Automatica | Year: 2012

A novel super-twisting adaptive sliding mode control law is proposed for the control of an electropneumatic actuator. The key-point of the paper is to consider that the bounds of uncertainties and perturbations are not known. Then, the proposed control approach consists in using dynamically adapted control gains that ensure the establishment, in a finite time, of a real second order sliding mode. The important feature of the adaptation algorithm is in non-overestimating the values of the control gains. A formal proof of the finite time convergence of the closed-loop system is derived using the Lyapunov function technique. The efficiency of the controller is evaluated on an experimental set-up. © 2012 Elsevier Ltd. All rights reserved. Source

Zerrik E.H.,Moulay Ismai University | Sidi M.O.,Al Jouf University
IET Control Theory and Applications | Year: 2013

In this study, the authors consider the problem of optimal regional controllability of a distributed bilinear system evolving in a spatial domain ω. The question is to obtain a bounded feedback control with minimum energy that drives such a system from an initial state to a desired one in finite time, only on a subregion ω of ω. The purpose of this study is to prove that a regional optimal control exists, and characterised as a solution to an optimality system. Numerical approach is given and successfully illustrated by simulations. © The Institution of Engineering and Technology 2013. Source

Boutammachte N.,Moulay Ismai University | Knorr J.,TU Dresden
Solar Energy | Year: 2012

The ultimate aim of a Moroccan-German study is to develop a simple solar pumping system, using the concept of low delta-T Stirling engines. This paper describes the main parts of the engine and presents several experimental measurements made under laboratory and field-test conditions in Morocco. Measurements with flat plate cooler and discontinuous motion of the displacer were conducted to verify two essential recommendations of Kolin in expectation of power-output improvements of the gamma-type engine. © 2012 Elsevier Ltd. Source

Following the recent stratigraphic works carried out on the Jurassic-Cretaceous boundary in the external Rif chain (Mesorif area and Bou Haddoud nappe), numerous submarine volcanism traces have been discovered in Upper Oxfordian to Upper Berriasian deposits. These traces display various aspects: volcaniclastic complexes incorporated within Upper Berriasian marls; volcanic lavas and basalt clasts included in the breccias with clay matrix of Upper Oxfordian to Lower Berriasian age, or in brecciated Lower Tothonian calcareous beds of the Early Tithonian. These submarine volcanic activities took place in a carbonate platform environment during the Kimmeridgian to Early Tithonian interval or in a pelagic basin from Late Tithonian onwards. They caused an intense brecciation of Upper Jurassic carbonate formations and a general dismantling of marly calcareous alternations of Upper Tithonian-Lower Berriasian. Therefore, the Upper Tithonian-Lower Berriasian deposits are marked by frequent stratigraphic gaps in many outcrops of Mesorif, Prerif areas and in the Bou Haddoud nappe. © 2011 Académie des sciences. Source

Euro-Mediterranean policies, as well as research on them, have been characterized by a Euro-centric approach based on a narrow geopolitical construction of the Mediterranean. Moreover, stakeholders, policy instruments, and policy issues have been defined from a European standpoint, marginalizing the perspectives and needs of local states and people, and ignoring the role played by new and powerful regional and global actors. In an increasingly multipolar world, overcoming this Euro-centric approach is key for Europe to play a more meaningful role in the region. Thus, MEDRESET aims to reset our understanding of the Mediterranean and develop alternative visions for a new partnership and corresponding EU policies, reinventing a future role for the EU as an inclusive, flexible, and responsive actor in the region. This will be achieved through an integrated research design which is in three phases: it 1) de-constructs the EU construction of the Mediterranean, 2) counters it by mapping the region on the geopolitical level and in four key policy areas (political ideas, agriculture and water, industry and energy, migration and mobility) alongside a three-dimensional framework (stakeholders, policy instruments, policy issues), which directly feeds into 3) a reconstruction of a new role for the EU, enhancing its ability to exert reflexive leadership and thus its relevance in the region. Embedded in an interdisciplinary research team, as well as in a civil society and media network, MEDRESET evaluates the effectiveness and potential of EU policies by investigating whether current policies still match the changing geopolitical configuration of the Mediterranean area. The perceptions of EU policies and the reasons for their successes or failures are assessed by surveying top-down and bottom-up stakeholders on both shores of the Mediterranean. Country-tailored policy recommendations for the EU will be given for four key countries: Egypt, Lebanon, Morocco, and Tunisia.

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