National Center for Scientific and Technical Research

Rabat, Morocco

National Center for Scientific and Technical Research

Rabat, Morocco
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Kouyate D.,Cadi Ayyad University | Soderlund U.,Lund University | Soderlund U.,Swedish Museum of Natural History | Youbi N.,Cadi Ayyad University | And 9 more authors.
Lithos | Year: 2013

Precambrian inliers of the Anti-Atlas belt in the southern part of Morocco contain numerous dolerite dyke and sill swarms which were previously poorly dated. Four dykes and two sills dated by the U-Pb TIMS method on baddeleyite and zircon provide the first steps toward a magmatic 'barcode' for the West African Craton (WAC) and constraints on the timing of breakup of the WAC from Precambrian supercontinents. A 2040. ±. 2. Ma (U-Pb zircon) age for a WNW dyke in the Zenaga inlier, matches the published age of a dyke in the Tagragra of Tata inlier, and also those of Eburnean granites observed in several inliers, which are collectively interpreted to represent ca. 2040. Ma bimodal magmatism due to a mantle plume. Based on the presence of matching 2040. Ma ages, the WAC may have been connected to the North Atlantic Craton at the initial stage of fragmentation of a late Archean continent. U-Pb baddeleyite ages of 1656. ±. 9. Ma and ca. 1655. Ma from sills in the Zenaga inlier and 1654. ±. 16. Ma from a NE-trending dyke in the Agadir Melloul inlier are similar to intraplate magmatic ages in eastern and northern Baltica, and support the SAMBA reconstruction (part of the Nuna supercontinent) of the WAC adjacent to Baltica. Approximate U-Pb ages of 885. Ma for two dykes in the Iguerda-Taïfast and Zenaga inliers date a NE trending swarm (named herein the Iguerda-Taïfast swarm) which is connected to the initial breakup of the supercontinent Rodinia, and a specific link with the São Francisco/Congo and North China craton is considered. © 2012.


Font E.,University of Lisbon | Youbi N.,Cadi Ayyad University | Youbi N.,National Center for Scientific and Technical Research | Youbi N.,University of Lisbon | And 4 more authors.
Earth and Planetary Science Letters | Year: 2011

The origin of the Triassic-Jurassic (Tr-J) mass extinction is still a matter of debate: proponents of the idea that continental flood basalts of the Central Atlantic Magmatic Province (CAMP) are responsible for the crisis are opposed by those who favor an extraterrestrial origin linked to the impact of meteorite. Principal limitations reside in the difficulty to date and correlate CAMP lavas with the marine realm turnover. One argument widely used to suggest that CAMP lavas pre-dated the Tr-J boundary in Morocco is based on the presence of two brief magnetic reversals in the intermediate units of the Tiourjdal and Oued Lahr sections (Morocco) that were correlated to the E23r chron from the Newark basin and to the SA5n.2r/3r and SA5r chrons of the Saint Audrie Bay [Knight, K.B., Nomade, S., Renne, P.R., Marzoli, A., Betrand, H., Youbi, N., 2004. The Central Atlantic Magmatic Province at the Triassic-Jurassic boundary: paleomagnetic and 40Ar/30Ar evidence from Morocco for brief, episodic volcanism. Earth and Planetary Science Letters 228, 143-160]. However the primary origin for these negative (reverse) magnetic components is questionable since no field or reversal test was provided to constrain the primary character of the remanence as well as because the small number of samples. Here we have conducted a detailed paleomagnetic and magnetic mineralogy study of the interbedded limestones of the Tiourjdal section and of other CAMP lavas sections where the intermediate unit is complete, namely the Tizi El Hajaj, Jbel Imzar and Aït Ourir sections, to better constrain the origin and stratigraphic location of these negative magnetic components. We show that the interbedded limestones of the Tiourjdal section were entirely remagnetized by chemical processes via acid and oxidizing hydrothermal fluids generated by eruptions of CAMP lavas. In addition, magnetostratigraphic data of the Tizi El Hajaj, Jbel Imzar and Aït Ourir sections show that the entire intermediate unit encompassed a positive (normal) magnetic interval. A good quality paleomagnetic pole for the CAMP lava in Morocco is then provided (Plat=60.0°; Plong=241.6°; A95=2.6; N=99) that is now in better agreement with its trans-Atlantic counterpart. © 2011 Elsevier B.V.


Dagdougui H.,University of Genoa | Ouammi A.,National Center for Scientific and Technical Research | Sacile R.,University of Genoa
IEEE Transactions on Control Systems Technology | Year: 2014

The optimal control of the power flows in a network of microgrids (MGs) is presented. The problem is solved using the mathematical formalization of the optimal control based on the Pontryagin's minimum principle (PMP). The objective is to deliver an optimal control strategy for the minimization of the power flows among MGs, and to maintain the storage system operating around a given reference value. This study proposes an original formulation based on the PMP that may be viewed as a preliminary continuous time attempt to model and control the exchange of power in a network of MGs. Its main originality is the use and the exchange of information and forecast of energy production and consumption on the whole set of MGs, to improve the overall quality of the power management, and energy storage. A method based on the PMP is developed to solve the corresponding constrained optimal control problem in an almost exclusively analytical way and thus, to calculate the optimal control. To prove the viability of the proposed approach, an example has been solved for the case of four MGs collaborating in a network. © 1993-2012 IEEE.


Salhi Y.,Université Ibn Tofail | Cherrouf S.,Université Ibn Tofail | Cherkaoui M.,Université Ibn Tofail | Abdelouahdi K.,National Center for Scientific and Technical Research
Applied Surface Science | Year: 2016

The electrodeposition of Sn-Zn coating at ambient temperature was investigated. The bath consists of metal salts SnCl2·2H2O and ZnSO4·7H2O and sodium citrate (NaC6H5Na3O7·2H2O) as complexing agent. To prevent precipitation, the pH is fixed at 5. Reducing tin and zinc through Sncit2- and ZnHcit- complex respectively is confirmed by the presence of two cathodic peaks on the voltammogram. The kinetic of tin (II) reduction process is limited by the SnCit2- dissociation. The SEM and TEM observations have showed that the coating consists of a uniform Sn-Zn layer composed of fine grains on which tin aggregates grow up. XRD revealed peaks corresponding to the hexagonal Zn phase and the tetragonal β-Sn phase. © 2016 Elsevier B.V. All rights reserved.


Dagdougui H.,École de Technologie Supérieure of Montreal | Ouammi A.,National Center for Scientific and Technical Research | Dessaint L.,École de Technologie Supérieure of Montreal | Sacile R.,Genova Engineering, LLC.
IET Renewable Power Generation | Year: 2016

This study addresses an optimisation problem faced by a network of green buildings (NGBs) connected to the main electrical grid. The problem is formulated as a cooperative internal power control among interacting residential buildings. The cooperation is reached through a communication infrastructure in the NGB, where the global central controller of the network is the responsible for the coordination of the local residential buildings' energy management systems by properly allowing the optimal management of the internal and external power flows in each building. The main advantage of the cooperation among residential buildings is to better match the load profile of each building internally (at the network level). In order to achieve this goal, components such as energy storage system, distributed generations and loads are included. The uncertainties characteristics of wind speed, solar irradiation, and loads are also considered for the control and operation of the whole system. A small network of five residential buildings has been simulated using the proposed model. Numerical results demonstrate the effectiveness of the proposed network. ©The Institution of Engineering and Technology 2016.


Ouammi A.,National Center for Scientific and Technical Research | Dagdougui H.,École de Technologie Supérieure of Montreal | Dessaint L.,École de Technologie Supérieure of Montreal | Sacile R.,University of Genoa
IEEE Transactions on Smart Grid | Year: 2015

In this paper, a model predictive control (MPC) for the optimal power exchanges in a smart network of power microgrids (MGs) is presented. The main purpose is to present an innovative control strategy for a cluster of interconnected MGs to maximize the global benefits. A MPC-based algorithm is used to determine the scheduling of power exchanges among MGs, and the charge/discharge of each local storage system. The MPC algorithm requires information on power prices, power generation, and load forecasts. The MPC algorithm is tested through case studies with and without prediction errors on loads and renewable power production. The operation of single MGs is simulated to show the advantage of the proposed cooperative framework relative to the control of a single MG. The results demonstrate that the cooperation among MGs has significant advantages and benefits with respect to each single MG operation. © 2015 IEEE.


Ouammi A.,National Center for Scientific and Technical Research
IEEE Transactions on Sustainable Energy | Year: 2016

This paper attempts to contribute to the development of a new concept focused on a cooperative control scheme for a smart network of residential buildings (SNRB) and to demonstrate advantages of interconnections and coordination among a set of smart residential buildings (SRBs), by taking advantages of fluctuations of stochastic renewable sources and loads, and exploiting the operational flexibilities of thermal loads defined as the required hot water and desired buildings temperature. A comprehensive finite-horizon scheduling optimization problem is formulated to optimally control a SNRB using model predictive control (MPC) method, which integrates both forecasts and newly updated information. The cooperation is reached through a bidirectional communication infrastructure in the SNRB, where the master controller (MC) is available at the network level and in charge of coordinating and managing power in the SNRB. A MPC-based algorithm is used for the future scheduling of power exchanges, charge/discharge state of each energy storage device (ESD), the state of each micro-CHP and the charging state of each plug-in electric vehicle (PEV) available in the network. The MPC strategy is tested through case studies where the influences of both network topology and thermal loads on the operation of each SRB are analyzed via numerical results. © 2016 IEEE.


Toufique Y.,Mohammed V University | El Moursli R.C.,Mohammed V University | Kaci M.,University of Valencia | El Kharrim A.,Premier University | Merrouch R.,National Center for Scientific and Technical Research
Proceedings of IEEE/ACS International Conference on Computer Systems and Applications, AICCSA | Year: 2013

The simulation of a real experiment using a GATEmodeled clinical Positron Emission Tomography (PET) scanner, namely PHILIPS Allegro, has been carried out using the Moroccan computing Grid infrastructure, MaGrid. In order to reduce the computing time, the PET simulation tasks are split into several jobs submitted to the Grid to run simultaneously. The splitting technique and merging the outputs are discussed. Results of the simulation are presented and good agreements are observed with experimental data. © 2013 IEEE.


Ouammi A.,National Center for Scientific and Technical Research | Dagdougui H.,University of Genoa | Sacile R.,University of Genoa
IEEE Transactions on Control Systems Technology | Year: 2014

In this paper, a centralized control model for optimal management and operation of a smart network of microgrids (SNMs) is designed. The proposed control strategy considers grid interconnections for additional power exchanges. This paper is based on an original Linear Quadratic Gaussian (LQG) problem definition for the optimal control of power flows in a SNMs. The control strategy incorporates storage devices, various distributed energy resources, and loads. The objective function aims to minimize the power exchanges among microgrids (MGs), and to make each local energy storage system in a MG works around a proper optimal value. The proposed model is evaluated through a case study in the Savona district, Italy, consisting of four MGs that cooperate together under an SNMs connected to a main grid. The case study shows that the proposed approach can effectively cope with the aim to decrease the intermittencies effects of renewable energy sources, and to manage real-time burst in the residential local demands. © 2014 IEEE.


El Azreq M.A.,Mohamed Vth University | El Hammoumi A.,Mohamed Vth University | Iben Brahim A.,National Center for Scientific and Technical Research | Kerroum M.,Mohamed Vth University | And 6 more authors.
Advanced Studies in Theoretical Physics | Year: 2013

The earthen building construction is an ancient technique that is experiencing resurgence in the world today thanks to the energy performance of this material throughout the life cycle of building phases of construction, occupancy and demolition. This strength allows us to consider the earth as a promising material in the construction sector in the context of sustainable development. Yet, there remain problems of quantification of the mechanical performance that prevent people to use this material. This paper is devoted to the study of these problems. Through numerical modeling of a wall of mud, I propose to optimize the composition to increase its resistance; the optimization also affects its size. A nonlinear dynamic behavior of the wall allowed us to study the conditions of its stability. Reinforcement techniques to improve the seismic capacity of the mud walls were also discussed. All these parameters characterize what we have agreed to call a mud wall SANS (sandblasted, armed, non-stabilized).

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