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Seawater Intrusion and Nitrate Contamination in the Fum Al Wad Coastal Plain,South Morocco

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Journal of Earth Science 2023年第6期34卷 1940-1950页

作者： Abderrazak Errich Souad El hajjaji Mohamed Fekhaoui belkheir ha.mouti Khalil Azzaoui Abdellatif Lamhamdi Shehdeh Jodeh Laboratory of Spectroscopy Molecular ModelingMaterialsNanomaterialsWater and Environment(LS3MN2E-CERNE2D)Department of ChemistryFaculty of SciencesMohammed V University in RabatRabatMorocco Scientific Institute Mohammed V University in RabatRabatMorocco Euro-Mediterranean of Fez(UEMF)BP.15 30070 FezMorocco Laboratory of Engineering ElectrochemistryModeling and EnvironmentFaculty of SciencesSidi Mohamed Ben Abdellah UniversityFez 30000Morocco Laboratory of Applied Sciences National School of Applied Sciences d'Al-hoceimaAbdelmalek Essaadi UniversityBP 03 AjdirMorocco Department of Chemistry An-Najah National UniversityNablusPalestine

The coastal plain aquifer down gradient of Wad Essaquia Elhamra(WEE),is the main source of groundwater in the arid region of Laayoune Essaquia El hamra located in south of *** over-exploitation of this aquifer over the last decade for water supply,agriculture and industry led to deterioration of groundwater quality,including seawater *** objective of this study is to investigate the spatial variation of groundwater quality,and to assess the influence of sea water intrusion on the groundwater quality using hydro-chemical *** measurement campaigns of physico-chemical parameters of the groundwater were performed,which shows a very high mineralization ratios versus chloride,confirming the double influence of mixing mechanisms of fresh and saline waters and the water-rock *** seawater fraction for sampled water shows that the average mixing rate of seawater intrusion reached 10.5%,confirming the marine intrusion in the *** highest values were registered in coastal *** the upstream around Laayoune and the spreading area,nitrate concentrations exceed 50 mg/L which is the threshold set by the World Health Organization,revealing a high level of contamination by domestic *** combination of ionic ratios and seawater fraction is a useful tool to assess marine *** study reveals that the phenomenon of marine intrusion is not the only process that dominates hydrochemistry of ground *** high groundwater mineralization is also due to rockwater interaction associated with reverse ion exchange with clay material and anthropogenic pollutants.

关键词： coastal aquifer saltwater intrusion nitrate pollution Fum El Wad aquifer groundwa-ter water supply

Non-expansive Mappings and Iterative Methods in Uniformly Convex Banach Spaces

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Acta Mathematica Sinica,English Series 2004年第5期20卷 829-836页

作者： ha|YunZHOU Dept.ofMath. ShijiazhuangMechanicalEngineeringCollegeShijiazhuang050003P.R.China

In this article,we will investigate the properties of iterative sequence for non-expansive mappings and present several strong and weak convergence results of successive approximations to fixed points of non-expansive mappings in uniformly convex Banach *** results presented in this article generalize and improve various ones concerned with constructive techniques for the fixed points of non-expansive mappings.

关键词： Non-expansive mapping Mann and lshikawa iteration schemes Convergence theorem Uniformly convex Banach space

Effects of Material and Dimension on TCF,Frequency,and Q of Radial Contour Mode AlN-on-Si MEMS Resonators

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Journal of Electronic Science and Technology 2021年第4期19卷 319-334页

作者： Thi Dep ha with the Faculty of Electronics Technology Industrial University of Ho Chi Minh CityHo Chi Minh City 70000

This paper investigates the effects of material and dimension parameters on the frequency splitting,frequency drift,and quality factor(Q)of aluminium nitride(AlN)-on-n-doped/pure silicon(Si)microelectromechanical systems(MEMS)disk resonators through analysis and *** parameters include the crystallographic orientation,dopant,substrate thickness,and *** resonators operate in the elliptical,higher order,and flexural *** simulation results show that i)the turnover points of the resonators exist at 55°C,-50°C,40°C,and-10°C for n-doped silicon with the doping concentration of 2×1019 cm-3 and the Si thickness of 3.5μm,and these points are shifted with the substrate thickness and mode variations;ii)compared with pure Si,the modal-frequency splitting for n-doped Si is higher and increases from 5%to 10%for all studied modes;iii)Q of the resonators depends on the temperature and ***,the turnover,modal-frequency splitting,and Q of the resonators depend on the thickness and material of the substrate and the *** work offers an analysis and design platform for high-performance MEMS gyroscopes as well as oscillators in terms of the temperature compensation by n-doped Si.

关键词： Anisotropic contour mode doping gyroscope microelectromechanical systems(MEMS)resonator piezoelectric temperature coefficient of frequency(TCF) temperature compensation thin-film piezoelectric-on-substrate(TPoS)

Current state-of-the-art review of footwear–ground friction

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Friction 2024年第10期12卷 2188-2204页

作者： David REBENDA Tomáš SÁha Footwear Research Centre University InstituteTomas Bata University in ZlinZlin 76001Czech Republic Faculty of Mechanical Engineering Brno University of TechnologyBron 61600Czech Republic

The most important role of footwear is to ensure safe,functional walking,and foot *** the proper functionality of not only the work shoes,the anti-slip behavior of the shoe under various conditions and environments plays an important role in the prevention of slips,trips,falls,and consequent *** article is intended to review the current understanding of the frictional mechanisms between shoe outsoles and various counterfaces that impact the evaluation of outsole *** research focuses on the mechanisms driving outsole friction on different ground surfaces or the definition and description of parameters that influence outsole ***,the review discusses the effect of various surface contaminants on footwear ***,challenges and outlooks in the field of footwear outsoles are briefly mentioned.

关键词： shoe outsole composite slipperiness coefficient of friction(COF) adhesion safe walk

Note on the Linearity of Bayesian Estimates in the Dependent Case

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Applied Mathematics 2014年第1期5卷 47-54页

作者： Souad Assoudou belkheir Essebbar Department of Economics Faculty of Law Economics and Social Sciences Hassan I University Settat Morocco Department of Mathematics and Computer Sciences Faculty of Science Mohammed V University Rabat Morocco

This work deals with the relationship between the Bayesian and the maximum likelihood estimators in case of dependent observations. In case of Markov chains, we show that the Bayesian estimator of the transition proba... 详细信息

关键词： Bayes Estimator Maximum Likelihood Estimator Markov Chain Transition Probabilities Jeffreys’ Prior Multivariate Beta Prior MCMC

Towards Understanding the Antieorrosive Mechanism of Novel Surfactant Based on Mentha pulegium Oil as Eco-friendly Bio-source of Mild Steel in Acid Medium: a Combined DFT and Molecular Dynamics Investigation

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Chemical Research in Chinese Universities 2019年第1期35卷 85-100页

作者： BOUOIDINA Asmae EL-haJJAJI Fadoua EMRAN Khadijanh BELGHITI Mohammed Elalaoui ELMELOUKY Abderrahmane TALEB Mustapha ABDELLAOUI Abdelfattah ha.mouti belkheir OBOT Ime Bassey Laboratory of Engineering ElectrochemistryModeling and EnvironmentFaculty of Sciences Sidi Mohamed Ben Abdellah UniversityFez 3500Morocco Department of Chemistry College of ScienceTaibah UniversityAl-Madinah Al-Monawarah PO Box4050Saudi Arabia Laboratory of Applied Analytical Chemistry Materials and Environment Faculty of Seiences University of Mohammed PremierOujda 60000Morocco Laboratoire Des Matieres Condensees et Physique Statistique Chouaib Doukkali University El-jadida 24000Morocco Laboratoire de Physiologie Pharmaeologie et Santo EnvironnementaleFaculty of Sciences Sidi Mohamed Ben Abdellah UniversityFez 3500Morocco Center of Research Excellence in Corrosion Research Institute King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia

Today,due to the increasingly stringent European directives concerning the use of molecules with certain toxicities towards the environment or their users,the essential oils,extracts,and molecules derived from plants exhibiting the characteristic of being biodegradable can be considered as a source of green corrosion inhibitors instead of harmful synthetic *** present work was devoted to testing the essential oil extracted from Mentha pulegium leaves(M1) as a corrosion inhibitor for C-steel in 1mol/L HCl solution using both electrochemical techniques and gravimetric measurements for the evaluation of the inhibition efficiencies at different *** results obtained showed that the inhibition efficiency increased with an increase in Ml concentration to reach a maximum value of 92.21%.We sought to determine the molecule responsible for this high efficiency,starting with the analysis of oil chemical composition by gas chromatography coupled with mass *** analysis revealed that menthol(M2)and isomenthol(M3)were the principal *** order to identify the molecule responsible for the inhibition and explain the protection mechanism involved,quantum chemical calculations and Monte Carlo simulations were used to explain the interaction of menthol,the major constituent of M1 with the *** practically confirm these results,we studied the action of 1mol/L HCl on steel with and without the addition of M2 by both methods(gravimetric and electrochemical study).A very high efficiency was obtained,an efficiency of 94.90% at 10^-3 mol/L,which was retained for a long exposure time,and slightly decreased in function of ***,a good correlation between the experimental data,theoretical calculations,and SEM studies was obtained,which denied that the Ml efficiency was only a result of a synergy effect and confirmed the high efficiency of Mentha oil and its main component(menthol)as a strong ecological inhibitor of corrosion.

关键词： Corrosion Ecological inhibitor Menthapulegium Menthol Density functional theory Monte Carlo simulation

Some remarks on the genericity of unique range sets for meromorphic functions

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Science China Mathematics 2005年第z1期48卷 262-267页

作者： ha Huy Khoai Institute of Mathematics 18 Hoang Quoc Viet 10307HanoiVietnam

In this paper we relate the study of unique range sets for meromorphic functions (URSM) with the hyperbolic hypersurfaces and give some remarks on the genericity of unique range sets for meromorphic functions.

关键词： unique range set for meromorphic functions, hyperbolic surface.

Support vector machine based machine learning method for GS 8QAM constellation classification in seamless integrated fiber and visible light communication system

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Science China(Information Sciences) 2020年第10期63卷 182-193页

作者： Wenqing NIU Yinaer ha Nan CHI Key Laboratory for Information Science of Electromagnetic Waves (MoE) Fudan University

Visible light communication(VLC) network over optical fiber has become a potential candidate in ultra-high speed indoor wireless communication. To mitigate signal distortion accumulated in optical fiber and VLC channel, we present to utilize support vector machine(SVM) for constellation classification in two kinds of geometrically-shaped 8 QAM(quadrature amplitude modulation) seamless integrated fiber and VLC system. We introduce 4 sub-bands to simulate multi-user. Experimental results show that system performance can be significantly improved, and transmission at-2.5 dB m input optical power under 7%forward error correction(FEC) threshold can be realized employing Circular(7, 1) geometrically-shaped8 QAM and SVM. At overall capacity of 960 Mbps, Q-factor increases by up to 11.5 dB.

关键词： visible light communication VLC support vector machine SVM geometrically shaping GS VLC network constellation classification

Discounted Iterative Adaptive Critic Designs With Novel Stability Analysis for Tracking Control

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IEEE/CAA Journal of Automatica Sinica 2022年第7期9卷 1262-1272页

作者： Mingming ha Ding Wang Derong Liu School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing 100083China Faculty of Information Technology the Beijing Key Laboratory of Computational Intelligence and Intelligent Systemthe Beijing Laboratory of Smart Environmental Protectionand the Beijing Institute of Artificial IntelligenceBeijing University of TechnologyBeijing 100124China Department of Electrical and Computer Engineering University of Illinois at ChicagoChicago IL 60607 USA IEEE

The core task of tracking control is to make the controlled plant track a desired *** traditional performance index used in previous studies cannot eliminate completely the tracking error as the number of time steps *** this paper,a new cost function is introduced to develop the value-iteration-based adaptive critic framework to solve the tracking control *** the regulator problem,the iterative value function of tracking control problem cannot be regarded as a Lyapunov function.A novel stability analysis method is developed to guarantee that the tracking error converges to *** discounted iterative scheme under the new cost function for the special case of linear systems is ***,the tracking performance of the present scheme is demonstrated by numerical results and compared with those of the traditional approaches.

关键词： Adaptive critic design adaptive dynamic programming(ADP) approximate dynamic programming discrete-time nonlinear systems reinforcement learning stability analysis tracking control value iteration(VI)