Using the GPS Station to Study Wind and Coastal Morpho-dynamics in North-eastern Morocco

The purpose of this work is to evaluate the potential of Global Positioning System (GPS) measurements for the monitoring of aeolian and coastal dynamics. The studied sites are the Moulouya estuary, Bouarfa’s area and Tigri Chott. The study shows that GPS is used to determine the dune kinematics and the Moulouya estuary in 3-D with an annual temporal resolution and a sub-centimeter accuracy. The GPS measurements carried out between 2013 and 2021 have shown spatial and temporal variations of the dune kinematics and Moulouya estuary. The results presented here show that the GPS measurements have the capability of continuously surveying the geomorphological entities’ kinematics with small and slow displacements and thus, they could complement conventional topometric techniques in a warning system

Design of a Uranium Dioxide Spheroidization System

The plasma spheroidization system (PSS) is the first process in the development of tungsten-uranium dioxide (W-UO2) fuel cermets. The PSS process improves particle spherocity and surface morphology for coating by chemical vapor deposition (CVD) process. Angular fully dense particles melt in an argon-hydrogen plasma jet at between 32-36 kW, and become spherical due to surface tension. Surrogate CeO2 powder was used in place of UO2 for system and process parameter development. Particles range in size from 100 - 50 microns in diameter. Student s t-test and hypothesis testing of two proportions statistical methods were applied to characterize and compare the spherocity of pre and post process powders. Particle spherocity was determined by irregularity parameter. Processed powders show great than 800% increase in the number of spherical particles over the stock powder with the mean spherocity only mildly improved. It is recommended that powders be processed two-three times in order to reach the desired spherocity, and that process parameters be optimized for a more narrow particles size range. Keywords: spherocity, spheroidization, plasma, uranium-dioxide, cermet, nuclear, propulsio

Ecoulements de convection forcée en régimes dynamique et thermique non établis dans un espace annulaire

Ce travail a pour objet l’ttude de I’ecoulement laminaire de convection fox& en regimes dynamique et thermique non bablis dans la region d’entree d’un espace annulaire compris entre deux cylindres coaxiaux et isothermes. La resolution du probleme a W faite par la methocle des differences finies. Ainsi nous avons obtenu les champs de vitesse et de temperature pour plusieurs combinaisons du rapport des rayons, du nombre de Reynolds, du nombre de Peclet et de la tempkrature du fluide B l’entrke. Ce qui nous a permis d’ttablir des corr&ations pour les longueurs d’kablissement dynamique et thermique et d’analyser le transfert de chaleur au niveau des parois

BEHAVIOR AND GLUTAMATE TRANSAMINASE CHANGES IN RAT EXPOSED TO LEAD AND TREATED BY WORMWOOD EXTRACT

Objective: Lead poisoning induced severe behavioral abnormalities and impaired cognitive functions in experimental animals. The aim of the present study is to investigate the detrimental effects of lead exposure on the behavior of rats and its association with altered neurochemistry.Methods: Twenty-four young male Wistar rats were divided into 4 groups: G1: a control group receiving drinking water. G2: intoxicated group (Pb) exposed to lead acetate (1000 ppm in drinking water). G3: receives Wormwood aqueous (A. Ab) extract at a dose of 300 mg/l in drinking water. G4: rats are receiving Pb+A. Ab mixture for 4 additional weeks after intoxication for 8 w. In the present study, locomotors activity in rats was assessed by open field test (OFT) while anxiety and depressive behavior were monitored by elevated plus maze (EPM) and the forced swim test (FST), the evaluation of glutamate metabolizing enzymes in whole brain and lipid peroxidation was carried out in all groups.Results: our results showed that lead acetate intoxication increased the level of lipid peroxidation in brain, decreased brain glutamate oxaloacetate transaminase activities and increased glutamate pyruvate transaminase. Also, lead (pb) exposure resulted in increased anxiety and fear-related behavior in both elevated plus maze and light dark box tests, showed hyperactivity in open field test presented by increased horizontal locomotion. However, A. Ab extract reduced the TBARS level by preventing oxidative stress induced by lead and increased glutamate pyruvate transaminase activity.Conclusion: The wormwood extract administration reduced anxiety, fear and locomotion and improved learning ability and memories. Therefore, these results indicated that wormwood is ameliorating the deleterious effects of lead and it appeared to be a protective agent against lead-induced toxicity.Â

Soil Erosion Evaluation and Mapping Based on Geomatic Techniques in Wadi El Malleh Watershed

Soil erosion by water considered is serious problem in the Mediterranean region due to the climate aggressiviness of the mountainous terrain, the traditional farming practices and other anthropogenic pressure on its land and soil. The present study was scheduled to use Geographical Information System (GIS), Remote Sensing data and the Revised Universal Soil Loss Equation (RUSLE) model to evaluate the annual average soil loss and sedimentation rate from Wadi El Malleh watershed, which is located in the Northern-Fez (Morocco), and covers an area of 34 km2 . In fact, RUSLE and SEDIMENTATION models were combined with GIS techniques to predict the spatiotemporal distribution of soil erosion and deposition under different land uses. The land use was assessed using the Google Earth image, which was taken in 2013. The image was first geo-referenced and projected into Moroccan coordinates system and classified by ArcGIS software. The use of RUSLE model allowed the estimation of static soil loss. Then the results of RUSLE were applied in the deposition modelling calculations to assess the spread of soil loss downstream by SEDIMENTATION model. The values of the annual net soil erosion obtained by this study were (81.86 t/ha/y) in bad land, (-19.19 t/ha/y) in irrigated agriculture areas and (-13.66 t/ha/y) in reforestation land where the negative values indicated deposition

TECHNIQUE OF CONTROL PMSM POWERED BY PV PANEL USING PREDICTIVE CONTROLLER OF DTC-SVM

The present paper is a part of the study of Direct Torque Control based (DTC) on space vector modulation using predictive controller (Predictive SVM) of a permanent magnet synchronous motor (PMSM) powered by a photovoltaic (PV) source. In the conventional direct torque control (DTC) of a permanent magnet synchronous motor (PMSM), hysteresis controllers are used to choose the proper voltage vector resulting in large torque ripples. The direct torque control can accelerate the torque responses but increases the torque ripple at same time. Nowadays, exist some other alternative approaches to reduce the torque ripples based on (Predictive SVM) technique. This method is based on the replacement of hysteresis comparators (used in conventional DTC) by Proportional Integral (PI) regulators and the selection table by space vector modulation (SVM). The simulation results confirm that this proposed method where the control of the switching frequency is well controlled, allows us to reduce the oscillations of the electromagnetic torque and flux by 20 % and 30%, respectively with a good dynamic response compared with conventional DTC

On the Ulam-Hyers-Rassias stability of two structures of discrete fractional three-point boundary value problems: existence theory

We prove existence and uniqueness of solutions to discrete fractional equations that involve Riemann-Liouville and Caputo fractional derivatives with three-point boundary conditions. The results are obtained by conducting an analysis via the Banach principle and the Brouwer fixed point criterion. Moreover, we prove stability, including Hyers-Ulam and Hyers-Ulam-Rassias type results. Finally, some numerical models are provided to illustrate and validate the theoretical results.The Portuguese Foundation for Science and Technology (FCT) and CIDMA. NSRF via the Program Management Unit for Human Resources & Institutional Development, Research and Innovation.publishe