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Nonlinear boundary control problem of hyperbolic systems

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Journal of Control and Decision 2024年第1期11卷 73-83页

作者： A.Bouhamed A.El Kabouss H.Bouzahir ISTI Lab Ibn Zohr UniversityENSAAgadirMorocco Faculty of sciences Moulay Ismail UniversityMeknesMorocco

The paper is devoted to the study of optimal control of a hyperbolic system,where the control enters the system through the boundary.The hyperbolic system is the wave equation on a smooth and open domain,where the boundary condition involves the normal derivative at the boundary of z,the time derivative of z times a constant k,and a nonlinear term control.Here,z is the state and u is the control,satisfying some boundedness condition depending on k.The functional cost consists of the energy and the difference between the solution of the system at final time,and a desired state in L2-norm.For a closed convex set,we prove the existence of an optimal control that minimises the cost functional using a priori estimates.Then,using the differentiability of the cost functional with respect to the control,we establish the characterisation by deriving necessary conditions that an optimal control must satisfy.A numerical approach is successfully illustrated by simulations.

关键词： Non-linear system hyperbolic system boundary control optimal control controllability

Electro-Optical Model of Soiling Effects on Photovoltaic Panels and Performance Implications

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Energy Engineering 2024年第2期121卷 243-258页

作者： A.Asbayou G.P.Smestad I.Ismail A.Soussi A.Elfanaoui L.Bouhouch A.Ihlal Laboratory of Materials and Renewable Energies University Ibn ZohrAgadir80000Morocco Sol Ideas Technology Development San José95150USA

In this paper,a detailed model of a photovoltaic(PV)panel is used to study the accumulation of dust on solar panels.The presence of dust diminishes the incident light intensity penetrating the panel’s cover glass,as it increases the reflection of light by particles.This phenomenon,commonly known as the“soiling effect”,presents a significant challenge to PV systems on a global scale.Two basic models of the equivalent circuits of a solar cell can be found,namely the single-diode model and the two-diode models.The limitation of efficiency data in manufacturers’datasheets has encouraged us to develop an equivalent electrical model that is efficient under dust conditions,integrated with optical transmittance considerations to investigate the soiling effect.The proposed approach is based on the use of experimental current-voltage(I-V)characteristics with simulated data using MATLAB/Simulink.Our research outcomes underscores the feasibility of accurately quantifying the reduction in energy production resulting from soiling by assessing the optical transmittance of accumulated dust on the surface of PV glass.

关键词： Photovoltaics solar energy optical transmittance soiling dust PV performance

Existence and numerical approximation of a solution to frictional contact problem for electro-elastic materials

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 201-219页

作者： Othman Baiz EL-Hassan Benkhira Rachid Fakhar university ibn zohr Lab.ESERFP of OuarzazateMorocco university Moulay Ismail Faculty of SciencesLaboratory MACSESTMBP 3103Toulal-MeknesMorocco university Sultan Moulay Slimane Laboratory LS2MEPolydisciplary Faculty of Khouribga25000 KhouribgaMorocco

In this paper,a frictional contact problem between an electro-elastic body and an electrically conductive foundation is studied.The contact is modeled by normal compliance with finite penetration and a version of Coulomb’s law of dry friction in which the coefficient of friction depends on the slip.In addition,the effects of the electrical conductivity of the foundation are taken into account.This model leads to a coupled system of the quasi-variational inequality of the elliptic type for the displacement and the nonlinear variational equation for the electric potential.The existence of a weak solution is proved by using an abstract result for elliptic variational inequalities and a fixed point argument.Then,a finite element approximation of the problem is presented.Under some regularity conditions,an optimal order error estimate of the approximate solution is derived.Finally,a successive iteration technique is used to solve the problem numerically and a convergence result is established.

关键词： piezoelectric material frictional contact variational Inequality fixed point process finite element method error estimation iteration method

Thermo-Physical Potential of Recycled Banana Fibers for Improving the Thermal and Mechanical Properties of Biosourced Gypsum-Based Materials

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Journal of Renewable Materials 2024年第4期12卷 843-867页

作者： Youssef Maaloufa Soumia Mounir Sara ibnelhaj Fatima zohra El Wardi Asma Souidi Yakubu Aminu Dodo Malika Atigui Mina Amazal Abelhamid Khabbazi Hassan Demrati Ahmed Aharoune National School of Architecture Agadir New ComplexIbn Zohr UniversityAgadirMorocco Energy Materials and Sustainable Development(EMDD)Center for WaterNatural ResourcesEnvironment and Sustainable Development(CERNE2D)Mohammed V UniversityRabatMorocco Thermodynamics and Energetics Laboratory Faculty of ScienceIbn Zohr UniversityAgadirMorocco Architectural Engineering Department Najran UniversityNajranSaudi Arabia The Centre of Scientific and Engineering Research Najran UniversityNajranSaudi Arabia Physics Department LPMAT LaboratoryFaculty of Sciences Ain ChockHassan II UniversityCasablancaMorocco

The development of bio-sourced materials is essential to ensuring sustainable construction;it is considered a locomotive of the green economy.Furthermore,it is an abundant material in our country,to which very little attention is being given.This work aims to valorize the waste of the trunks of banana trees to be used in construction.Firstly,the physicochemical properties of the fiber,such as the percentage of crystallization and its morphology,have been determined by X-ray diffraction tests and scanning electron microscopy to confirm the potential and the impact of the mode of drying on the quality of the banana fibers,with the purpose to promote the use of this material in construction.Secondly,the results obtained with the gypsum matrix allowed us to note a preponderant improvement in the composite’s thermal properties thanks to the variation of the banana fiber additive.Thirdly,the impact of the nature of the banana fiber distribution(either fiber mixed in matrix or fiber series model)on the flexural and compressive strengths of the composites was studied.The results obtained indicate that the insulation gain reaches up to 40%.It depends on the volume fraction and type of distribution of the banana fibers.However,the thermal inertia of the composites developed,represented by thermal diffusivity and thermal effusivity,was studied.Results indicate a gain of 40%and 25%,respectively,in terms of thermal diffusivity and thermal effusivity of the developed composites compared to plaster alone.Concerning the mechanical properties,the flexural strength depends on the percentage of the volume fraction of banana fibers used,and it can reach 20%more than the flexural strength of plaster;nevertheless,there is a significant loss in terms of the compressive strength of the studied composites.The results obtained are confirmed by the microstructure of the fiber banana.In fact,the morphology of the banana fibers was improved by the drying process.It reduces the amorphous area and improves the cellulosic crystalline surfaces,w

关键词： Biosourced materials fiber banana flexural strength mechanical properties open-air drying plaster thermal properties waste management

Cognitive Disorders, Depression and Anxiety in Temporal Lobe Epilepsy: An Overview

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Journal of Biosciences and Medicines 2024年第3期12卷 77-93页

作者： Amina Tani Nawal Adali REGNE Research Laboratory Faculty of Medicine and Pharmacy Agadir Morocco ENSA Ibn Zohr University Agadir Morocco Neurology Department University Hospital Agadir Morocco

Partial epilepsies, originating in a specific brain region, affect about 60% of adults with epilepsy. Temporal lobe epilepsy (TLE) is the most prevalent subtype within this category, often necessitating surgical intervention due to its refractoriness to antiepileptic drugs (AEDs). Hippocampal sclerosis, a common underlying pathology, often exacerbates the severity by introducing cognitive and emotional challenges. This review delves deeper into the cognitive profile of TLE, along with the risk factors for cognitive disorders, depression, and anxiety in this population.

关键词： Temporal Lobe Epilepsy Cognitive Disorders Anxiety Depression

Numerical Modeling and Technico-Economic Analysis of a Hybrid Energy Production System for Self-Consumption: Case of Rural Area in the Comoros

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Journal of Power and Energy Engineering 2024年第5期12卷 24-59页

作者： Fahad Maoulida Mohamed Aboudou Kassim Rabah Djedjig Ahmed Ihlal Mohammed El Ganaoui LERMAB Laboratory of Studies and Research on Wood Material IUT of Longwy University of Lorraine Cosnes-et-Romain Longwy France LEMA Energy and Applied Mechanics Laboratory Faculty of Sciences and Techniques University of Comoros Moroni Comoros IREMIS Institute University of Mayotte Mayotte France LMER Laboratory of Materials and Renewable Faculty of Sciences University Ibn Zohr BP Agadir Morocco

This study aims to provide electricity to a remote village in the Union of Comoros that has been affected by energy problems for over 40 years. The study uses a 50 kW diesel generator, a 10 kW wind turbine, 1500 kW photovoltaic solar panels, a converter, and storage batteries as the proposed sources. The main objective of this study is to conduct a detailed analysis and optimization of a hybrid diesel and renewable energy system to meet the electricity demand of a remote area village of 800 to 1500 inhabitants located in the north of Ngazidja Island in Comoros. The study uses the Hybrid Optimization Model for Electric Renewable (HOMER) Pro to conduct simulations and optimize the analysis using meteorological data from Comoros. The results show that hybrid combination is more profitable in terms of margin on economic cost with a less expensive investment. With a diesel cost of $1/L, an average wind speed of 5.09 m/s and a solar irradiation value of 6.14 kWh/m2/day, the system works well with a proportion of renewable energy production of 99.44% with an emission quantity of 1311.407 kg/year. 99.2% of the production comes from renewable sources with an estimated energy surplus of 2,125,344 kWh/year with the cost of electricity (COE) estimated at $0.18/kWh, presenting a cost-effective alternative compared to current market rates. These results present better optimization of the used hybrid energy system, satisfying energy demand and reducing the environmental impact.

关键词： Hybrid System Rural Area Electrification Comoros Techno-Economic Analysis PV-Wind-Diesel-Battery Meteorological Data HOMER Energy Pro

A New Variant of Wilson's Functional Equation on Monoids

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Acta Mathematica Sinica,English Series 2022年第8期38卷 1303-1316页

作者： Hajira DIMOU Elhoucien ELQORACHI Abdellatif CHAHBI Laboratory EEFA Faculty of Applied SciencesIbn Zohr UniversityAgadirMorocco Laboratory EEFA Department of MathematicsFaculty of SciencesIbn Zohr UniversityAgadirMorocco

We find on a monoid M the complex-valued solutions f,g:M→C such that f is central and g is continuous of the functional equation f(xσ(y))+f(τ(y)x)=2f(x)g(y),x,y∈M,whereσ:M→M is an involutive automorphism andτ:M→M is an involutive anti-automorphism.The solutions are described in terms of multiplicative functions,additive functions and characters of2-dimensional representations of M.

关键词： Monoid functional equation d'Alembert's equation involutive automorphism multiplicative function anti-automorphism

Structural and Physicochemical Properties of Dust and Their Effect on Solar Modules Efficiency in Agadir-Morocco

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Journal of Renewable Materials 2023年第5期11卷 2249-2264页

作者： Abdellah Asbayou Ahmed Ihlal Ismail Isknan Ahmed Soussi Lahoussine Bouhouch Materials and Renewable Energies Laboratory University Ibn ZohrAgadir80000Morocco

Experiments of soiling effects on the performances of a PV panel have been performed using dust collected from two sites in the region of Agadir-Morocco.The optical transmittance of the front glass was found to depend on the nature and density of dust.The nature of dust was studied by means of scanning electron microscopy and energy dispersive x-ray spectroscopy.It was found that the granulometry of dust particles depends on the study area.For a dust density of around 20 g/m^(2),the maximum power Pmax of the solar panel decreases drastically from 30 to 20 W for the(HP)site,and no more than 14 W for the(AD)site.The diversity of the behavior of the soiled panel was explained in terms of the size of the particles collected from each area.The transmission of light across the front glass of the PV panel is more affected when the sizes of particles are small.

关键词： Agadir PV panel soiling optical transmittance dust characterization

Coupled Conductive-Convective-Radiative Heat Transfer in Hollow Blocks with Two Air Cells in the Vertical Direction Subjected to an Incident Solar Flux

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Fluid Dynamics & Materials Processing 2022年第5期18卷 1399-1407页

作者： Mourad Najjaoui Thami Ait-taleb Abdelhalim Abdelbaki Zaki Zrikem Hassan Chaib Polydiscilinary Faculty of Ouarzazate Ibn Zohr UniversityOuarzazateMorocco Faculty of Sciences Semlalia Cadi Ayyad UniversityMarrakeshMorocco

This work presents the results of a set of steady-state numerical simulations about heat transfer in hollow blocks in the presence of coupled natural convection,conduction and radiation.Blocks with two air cells deep in the vertical direction and three identical cavities in the horizontal direction are considered(typically used for building ceilings).Moreover,their outside horizontal surface is subjected to an incident solar flux and outdoor environment temperature while the inside surface is exposed to typical indoor environment conditions.The flows are considered laminar and two-dimensional over the whole range of parameters examined.The conservation equations are solved by means of a finite difference method based on the control volumes approach,relying on the SIMPLE algorithm for what concerns the coupling of pressure and velocity.The effects of the number of cells in the horizontal direction and the thermal conductivity on the heat transfer through the alveolar structure have been investigated.The results show that the number of holes has a significant impact on the value of the overall heat flux through the considered structure.

关键词： Numerical simulation heat transfer coupled hollow concrete block control volumes approach