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A Conservative and Monotone Characteristic Finite element Solver for Three-Dimensional Transport and Incompressible Navier-Stokes Equations on Unstructured Grids

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Communications in Computational Physics 2022年第1期31卷 224-256页

作者： Bassou Khouya Mofdi el-Amrani mohammed Seaid International Water Research Institute University Mohammed VI PolytechnicBenguerirMorocco Mathematics and Applications Laboratory FSTAbdelmalek Essaadi UniversityTangierMorocco Department of Engineering University of DurhamSouth RoadDurham DH13LEUK

We propose a mass-conservative and monotonicity-preserving characteristic finite element method for solving three-dimensional transport and incompressibleNavier-Stokes equations on unstructured grids. The main idea in the proposed algorithm consists of combining a mass-conservative and monotonicity-preserving modified method of characteristics for the time integration with a mixed finite elementmethod for the space discretization. This class of computational solvers benefits fromthe geometrical flexibility of the finite elements and the strong stability of the modi-fied method of characteristics to accurately solve convection-dominated flows usingtime steps larger than its Eulerian counterparts. In the current study, we implementthree-dimensional limiters to convert the proposed solver to a fully mass-conservativeand essentially monotonicity-preserving method in addition of a low computationalcost. The key idea lies on using quadratic and linear basis functions of the mesh element where the departure point is localized in the interpolation procedures. Theproposed method is applied to well-established problems for transport and incompressible Navier-Stokes equations in three space dimensions. The numerical resultsillustrate the performance of the proposed solver and support its ability to yield accurate and efficient numerical solutions for three-dimensional convection-dominatedflow problems on unstructured tetrahedral meshes.

关键词： Mass-conservative monotonicity-preserving modified method of characteristics fi-nite element method convection-dominated problems incompressible Navier-Stokes equations

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Effect of smart sprinkler irrigation utilization on water use efficiency for wheat crops in arid regions

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International Journal of Agricultural and Biological Engineering 2014年第1期7卷 26-35页

作者： Hussein mohammed Al-Ghobari Mohamed Said Abdalla el Marazky Department of Agricultural Engineering College of Food and Agriculture Sciences King Saud UniversityRiyadh 11451Kingdom of Saudi Arabia

The smart irrigation system(SIS)developed in this research is a valuable tool for scheduling irrigation and quantifying water required by *** was implemented and tested under sprinkler irrigation system to irrigate wheat crops(YecoraRojo).Results obtained from this system were compared with the control irrigation system(CIS),whose scheduling method was based on data from an automatic weather *** indicated significant savings in applied water using the *** addition,the use of the SIS conserved 12%of irrigation water compared to CIS and obtained an economical *** water use efficiency(WUE)under SIS had generally higher values(1.64 kg/m^(3))compared to CIS(1.46 kg/m^(3)).Hence,the application of SIS technology provides significant advantages on WUE and irrigation water use efficiency(IWUE).Relatively high WUE and IWUE were found for the irrigation treatment(80%of evapotranspiration under SIS).Results showed that the irrigation requirements of wheat increased(100%of ETc under CIS)with increasing evapotranspiration(ETc)but excessive irrigation could decrease WUE and *** results indicated that extreme irrigation might not produce higher yield or optimal economic benefit,thus,suitable irrigation schedules by using SIS must be established and extendable to other agricultural crops.

关键词： smart irrigation system(SIS) sprinkler irrigation scheduling water use efficiency arid region evapotranspiration grain yield

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Detection of Impending Vehicle Rollover with Road Bank Angle Consideration Using a Robust Fuzzy Observer

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International Journal of Automation and computing 2015年第1期12卷 93-101页

作者： Hamid Dahmani mohammed Chadli Abdelhamid Rabhi Ahmed el Hajjaji University of Picardie Jules Verne-MIS Laboratory (EA4290) 33 rue Saint-Leu Amiens 80039 France

This article describes a method of vehicle dynamics estimation for impending rollover detection. We estimate vehicle dynamic states in presence of the road bank angle as a disturbance in the vehicle model using a robust observer. The estimated roll angle and roll rate are used to compute the rollover index which is based on the prediction of the lateral load transfer. In order to anticipate rollover detection, a new method is proposed to compute the time to rollover(TTR) using the load transfer ratio(LTR). The nonlinear model, deduced from the vehicle lateral and roll dynamics, is represented by a Takagi-Sugeno(T-S) fuzzy model. This representation is used to account for the nonlinearities of lateral cornering forces. The proposed T-S observer is designed with unmeasurable premise variables to cater for non-availability of the slip angles measurement. The proposed approach is evaluated using Car Sim simulator under different driving scenarios. Simulation results show good efficiency of the proposed T-S observer and the rollover detection method.

关键词： Vehicle rollover vehicle dynamics Takagi-Sugeno(T-S) fuzzy model observer uncertainties Lyapunov method linear matrix inequalities(LMI)

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Direct torque control of doubly fed induction motor using three-level NPC inverter

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Protection and Control of Modern Power Systems 2019年第1期4卷 208-216页

作者： Najib el Ouanjli Aziz Derouich Abdelaziz el Ghzizal mohammed Taoussi Youness el Mourabit Khalid Mezioui Badre Bossoufi Laboratory of Production Engineering Energy and Sustainable DevelopmentHigher School of TechnologySidi Mohamed Ben Abdellah UniversityFezMorocco Laboratory of Systems Integration and Advanced Technologies Faculty of Sciences Dhar El MahrazSidi Mohamed Ben Abdellah UniversityFezMorocco Laboratory of electrical Engineering and Maintenance ESTO School of TechnologyUniversity Mohammed IOujdaMorocco

This article presents the direct torque control (DTC) strategy for the doubly fed induction motor (DFIM) connected to two three-level voltage source inverters (3LVSIs) with neutral point clamped (NPC) structure. This control method allows to reduce the torque and flux ripples as well as to optimize the total harmonic distortion (THD) of motor currents. The use of 3LVSI increases the number of generated voltage, which allows improving the quality of its waveform and thus improves the DTC strategy. The system modeling and control are implemented in Matlab/Simulink environment. The analysis of simulation results shows the better performances of this control, especially in terms of torque and flux behavior, compared to conventional DTC.

关键词： Direct torque control Doubly fed induction motor Three-level inverter Ripples Switching table

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Surface Nanostructure Control with Poly(ethylene glycol)(PEG)Spacer by Templateless electropolymerization

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Journal of Bionic Engineering 2021年第1期18卷 65-76页

作者： Imen Bousrih Mejda el Kateb mohammed Beji Fréderic Guittard Thierry Darmanin University of Tunis el Manar Laboratory of Structural Organic ChemistryFaculty of Sciences of TunisTunis 2092Tunisia Universite Cote d'Azur NICE LabParc Valrose Nice 06100France

Controlling the shape of surface nanostructures is fundamental for various potential applications for cxamples,in water harvesting systems,liquid transportation or oil/water separation *** this paper,the creation of porous surface structures is made by a process called templateless electropolymerization,in which water(H_(2)0)is oxidizedreduced to form gas(O_(2)/H_(2))bubbles onto the surfaces and acting as soft template for the polymer *** the monomer(thieno[3,4-b]lhiophene)and the substituent(pyrene)constant,we demonstrate how a flexible PEG spacer can affect the structure *** the PEG spacer increases,the structures change frorm nanotubes(1D growth)to nanoribbons(2D)and after to hollow nanospheres(3D),which also affeets the wettig propertics.

关键词： nanostructures wettability hydrophobicity electrochemistry bioinspiration

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Modern improvement techniques of direct torque control for induction motor drives - a review

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Protection and Control of Modern Power Systems 2019年第1期4卷 138-149页

作者： Najib el Ouanjli Aziz Derouich Abdelaziz el Ghzizal Saad Motahhir Ali Chebabhi Youness el Mourabit mohammed Taoussi Laboratory of Production Engineering Energy and Sustainable DevelopmentHigher School of TechnologySidi Mohamed Ben Abdellah UniversityFezMorocco Faculty of Sciences and Technology University of Bordj Bou ArreridjBordj Bou ArreridjAlgeria Laboratory of Systems Integration and Advanced Technologies Faculty of Sciences Dhar El MahrazSidi Mohamed Ben Abdellah UniversityFezMorocco

Conventional direct torque control (DTC) is one of the excellent control strategies available to control the torque of the induction machine (IM). However, the low switching frequency of the DTC causes high ripples in the flux and torque that leads to an acoustic noise which degrades the control performances, especially at low speeds. Many direct torque control techniques were appeared to remedy these problems by focusing specifically on the torque and flux. In this paper, a state of the art review of various modern techniques for improving the performance of DTC control is presented. The objective is to make a critical analysis of these methods in terms of ripples reduction, tracking speed, switching loss, algorithm complexity and parameter sensitivity. Further, it is envisaged that the information presented in this review paper will be a valuable gathering of information for academic and industrial researchers.

关键词： Induction machine Direct torque Control(DTC) Fuzzy logic(FL) Neural network(NN) Sliding mode(SG) Genetic algorithm(GA)

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Cardiac changes in infants of diabetic mothers

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World Journal of Diabetes 2021年第8期12卷 1233-1247页

作者： mohammed Al-Biltagi Osama el razaky Doaa el Amrousy Department of Pediatrics Faculty of MedicineTanta UniversityTanta 35127Egypt Department of Pediatrics University Medical CenterArabian Gulf UniversityManama 26671Bahrain

Diabetes mellitus(DM)is a systemic chronic metabolic disorder characterized by increased insulin resistance and/orβ-cell *** affects all ages from the foetal life,neonates,childhood to late *** diabetes is a critical risk factor for congenital heart diseases(CHDs).Moreover,the risk increases with low maternal education,high body mass index at conception,undiagnosed pregestational diabetes,inadequate antenatal care,improper diabetes control,and maternal smoking during *** DM significantly affects the foetal heart and foetal-placental circulation in both structure and *** defects,myocardial hypertrophy are three times more prevalent in infants of diabetic mothers(IDMs).Antenatal evaluation of the cardiac function and structures can be performed with foetal electrocardiography and *** cardiac evaluation can be performed with natal and postnatal electrocardiography and echocardiography,detection of early atherosclerotic changes by measuring aortic intima-media thickness,and retinal vascular changes by retinal *** the effects of diabetes during pregnancy on the offspring depends mainly on pregestational and gestational diabetes ***,other measures to reduce the risk,such as using medications,nutritional supplements,or probiotics,still need more *** review discusses the mechanism of foetal sequels and the risk factors that increase the prevalence of CHDs in gestational DM,the various cardiac outcomes of gestational DM on the foetus and offspring,cardiac evaluation of foetuses and IDMs,and how to alleviate the consequences of gestational DM on the offspring.

关键词： Gestational diabetes mellitus Infants of diabetic mother Hypertrophic cardiomyopathy Congenital heart diseases Echocardiography Children

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Application of Internet of Things in the Health Sector:Toward Minimizing Energy Consumption

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Big Data Mining and Analytics 2022年第4期5卷 302-308页

作者： mohammed Moutaib Tarik Ahajjam mohammed Fattah Yousef Farhaoui Badraddine Aghoutane Moulhime el Bekkali IMAGE Laboratory Moulay Ismail UniversityMeknes 50000Morocco Department of Computer Science Faculty of Sciences and TechniquesMoulay Ismail UniversityErrachidia 52000Morocco IA Laboratory Faculty of ScienceMoulay Ismail UniversityMeknes 50000Morocco Sidi Mohamed Ben Abdellah University Fes 30000Morocco

The Internet of Things(IoT)is currently reflected in the increase in the number of connected objects,that is,devices with their own identity and computing and communication *** is recognized as one of the most critical areas for future technologies,gaining worldwide *** applies to many areas,where it has achieved success,such as healthcare,where a patient is monitored using nodes and lightweight ***,the powerful functions of IoT in the medical field are based on communication,analysis,processing,and management of data autonomously without any manual intervention,which presents many difficulties,such as energy ***,these issues significantly slow down the development and rapid deployment of this *** main causes of wasted energy from connected objects include collisions that occur when two or more nodes send data simultaneously and the leading cause of data retransmission that occurs when a collision occurs or when data are not received correctly due to channel *** distance between nodes is one of the factors influencing energy *** this article,we have proposed direct communication between nodes to avoid collision domains,which will help reduce data *** results show that the distribution can ensure the performance of the system under general conditions compared to the centralization and to the existing works.

关键词： Internet of Things(IoT) energy consumption cloud computing data storage

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Assessment of Indoor and Outdoor Radon Levels in South Lebanon

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International Journal of Disaster Risk Science 2014年第3期5卷 214-226页

作者： mohammed A.Kobeissi Omar el Samad Khaled Zahraman Ibrahim Rachidi Lebanese Atomic Energy Commission National Council for Scientific ResearchRiad ElsolhBeirutLebanon Department of Physics Faculty of Sciences(I)The Lebanese UniversityHadethBeirutLebanon

The presence of high indoor radon concentrations,Cx,is a major concern of the public *** of indoor radon in South Lebanon have been achieved using CR-39 *** ranged between 30 and 122 Bq m-3 in one of the major towns in the area and are compared with measured atmospheric air *** seasonal variation of Cxindoors has been observed,although 90%of the obtained indoor Cxmeasurements are below 100 Bq *** homes produced Cxreadings above the permissible *** showed that the ventilation effect played a major factor in reducing radon concentration levels *** assessment has been *** effective doses of radon varied from 1.01±0.10 to 8.65±0.50 m Sv a-1 in six homes in one of the four cases *** dosage values are above the permitted limit of 2.5 m Sv *** types of granite contained in the studied homes were identified and their contributions to radon levels indoors were calculated.

关键词： Building materials CR-39 Effective dose Granite exhalation rate Lebanon Radon risk assessment

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Formation of Nanotubular Structures with Petal Effect by Soft-Template electropolymerization of Benzotrithiophene with Hydrophilic Carboxyl Group

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Journal of Bionic Engineering 2022年第4期19卷 1054-1063页

作者： Maroua Khodja Imen Bousrih Mejda el Kateb mohammed Beji Frederic Guittard Thierry Darmanin Laboratory of Structural Organic Chemistry Faculty of Sciences of Tunis University of Tunis El Manar2092 TunisTunisia NICE Lab Universite Cote d’Azur06100 NiceFrance

The bioinspiration is one of the best ways to make a breakthrough in a field,and particularly in the wetting *** by natural species,such as rose petals and gecko foot,and previous researches,nanotubular structures are prepared here by soft-template electropolymerization in organic solvent and using an original benzotrithiophene with a hydrophilic carboxyl group,as the *** best results are obtained by cyclic voltammetry because of a much higher amount of gas bubbles released with this deposition *** nanoparticles and nanotubes are observed while the water content has an influence on the number of *** if the monomer has hydrophilic carboxyl group,the best films have both high hydrophobicity(apparent water contact angle up to 130.7°)and strong water adhesion(petal effect).These surfaces could be used in future in applications such as water harvesting systems.

关键词： Bioinspired electropolymerization Hydrophobicity Nanostructures Nanotubes Wettability

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