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Numerical Investigation and Optimization of a Flat Plate Solar Collector Operating with Cu/CuO/Al_(2)O_(3)–Water Nanofluids

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Transactions of Tianjin university 2021年第1期27卷 64-76页

作者： Youssef Belkassmi Kamal Gueraoui Lahoucine El maimouni Najem Hassanain Omar Tata ERMAM Polydisciplinary Faculty of OuarzazateIbn Zohr UniversityBox 638OuarzazateMorocco MSME Faculty of SciencesMohammed-V UniversityRabatMorocco Group of Semiconductors and Environmental Sensor Technologies-Energy Research Center Faculty of ScienceMohammed-V UniversityB.P.1014RabatMorocco GEMS Laboratory ENSAIbn Zohr UniversityB.P.1136AgadirMorocco

Nanofluids are a potential alternative to significantly improving the performance of heat transfer applications. In this work, a numerical analysis to examine the eff ect of dispersing copper(Cu), copper oxide(CuO), and aluminum(Al2O3) nanoparticles in pure water on the performance of a flat plate solar collector(FPSC) and a numerical model was proposed. The influence of the nanofluid type on the thermal efficiency was critically investigated and discussed. The eff ect of the mass flow rate on the performance was also analyzed and discussed. Based on correlations of the thermophysical properties of nanofluids, a sensitivity analysis was used to analyze the impact of the nanoparticles on the base fluid. The results indicate that the performance of the FPSC with Cu/water nanofluid was better than that of FPSCs using CuO/water or Al2O3/water nanofluids. When the mass flow rate of the nanofluids was 8.0 L/min, the efficiency of the FPSC was much greater than those at the flow rates of 5.0 L/min and 2.0 L/min. Mean enhancements in thermal efficiency of 4.44%, 4.27%, and 4.21% were observed when 2.0 L/min was applied using Cu/water, Cu O/water, and Al2O3/water nanofluids, respectively. Improvements in thermal efficiency of 2.76%, 2.53%, and 2.47% occurred when 8.0 L/min was applied.

关键词： Flat plate solar collector Solar energy Thermal efficiency Nanofluids Al_2O_3/water Cu/water CuO/water

Mathematical Validation of Proposed Machine Learning Classifier for Heterogeneous Traffic and Anomaly Detection

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Big Data Mining and Analytics 2021年第1期4卷 18-24页

作者： Azidine Guezzaz Younes Asimi Mourade Azrour Ahmed Asimi Department of Computer Science and Mathematics High School of TechnologyCadi Ayyad UniversityEssaouira 44000Morocco Department of Computer Science High School of TechnologyIbn Zohr UniversityGuelmim 81000Morocco IDMS Team Department of Computer ScienceFaculty of Science and TechnologyMoulay Ismail UniversityErrachidia 52000Morocco Department of Computer Science and Mathematics Faculty of Sciences AgadirIbn Zohr UniversityAgadir 80000Morocco

The modeling of an efficient classifier is a fundamental issue in automatic training involving a large volume of representative ***,automatic classification is a major task that entails the use of training methods capable of assigning classes to data objects by using the input activities presented to learn *** recognition of new elements is possible based on predefined *** detection systems suffer from numerous vulnerabilities during analysis and classification of data *** overcome this problem,new analysis methods should be derived so as to implement a relevant system to monitor circulated *** main objective of this study is to model and validate a heterogeneous traffic classifier capable of categorizing collected events within *** new model is based on a proposed machine learning algorithm that comprises an input layer,a hidden layer,and an output layer.A reliable training algorithm is proposed to optimize the weights,and a recognition algorithm is used to validate the *** is applied to the collected traffic prior to the analysis *** work aims to describe the mathematical validation of a new machine learning classifier for heterogeneous traffic and anomaly detection.

关键词： anomaly detection heterogeneous traffic preprocessing machine learning training classification

Low-voltage ride-through capability improvement of Type-3 wind turbine through active disturbance rejection feedback control-based dynamic voltage restorer

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Clean Energy 2023年第5期7卷 1091-1109页

作者： El Mahfoud Boulaoutaq Asma Aziz Abdelmounime El Magri Ahmed Abbou Mohamed Ajaamoum Azeddine Rachdy ibn zohr university Higher School of Technology Agadir School of Engineering Edith Cowan UniversityJoondalupWAaustralia Hassan II university of Casablanca National School of Technical Education Mohammed V university of Rabat Mohammadia School of Engineering

Disconnections due to voltage drops in the grid cannot be permitted if wind turbines(WTs)contribute significantly to electricity pro-duction,as this increases the risk of production loss and destabilizes the *** mitigate the negative effects of these occurrences,WTs must be able to ride through the low-voltage conditions and inject reactive current to provide dynamic voltage *** paper investigates the low-voltage ride-through(LVRT)capability enhancement of a Type-3 WT utilizing a dynamic voltage restorer(DVR).During the grid voltage drop,the DVR quickly injects a compensating voltage to keep the stator voltage *** paper proposes an active disturbance rejection control(ADRC)scheme to control the rotor-side,grid-side and DVR-side converters in a wind–DVR integrated *** performance of the Type-3 WT with DVR topology is evaluated under various test conditions using MATLAB®/Simulink®.These simulation results are also compared with the experimental results for the LVRT capability performed on a WT emulator equipped with a crowbar and direct current(DC)*** simulation results demonstrate a favourable transient and steady-state response of the Type-3 wind turbine quantities defined by the LVRT codes,as well as improved reactive power support under balanced fault *** the most severe voltage drop of 95%,the stator currents,rotor currents and DC bus voltage are 1.25 pu,1.40 pu and 1.09 UDC,respectively,conforming to the values of the LVRT *** controlled by the ADRC technique significantly increases the LVRT capabilities of a Type-3 doubly-fed induction generator-based WT under symmetrical voltage dip *** setting up ADRC controllers might be challenging,the proposed method has been shown to be extremely effective in reducing all kinds of internal and external disturbances.

关键词： active disturbance rejection controller(ADRC) dynamic voltage restorer(DVR) low-voltage ride-through(LVRT) Type-3 wind turbines(WTs) doubly-fed induction generator(DFIG)

Khettaras in the Taflalet oasis(Morocco):contribution to the promotion of tourism and sustainable development

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Built Heritage 2022年第4期6卷 35-50页

作者： Mohamed Beraaouz Mohamed Abioui Mohammed Hssaisoune Jesús Martínez‑Frías Laboratory of Applied Geology and Geo‑Environment Department of Erath SciencesFaculty of SciencesIbn Zohr UniversityAgadirMorocco. Monachus Group of Scientifc Research and Ecological Education ConstantaRomania. Faculty of Applied Sciences Ibn Zohr UniversityAit MelloulMorocco. Insti‑tuto de Geociencias CSIC-Universidad Complutense de MadridMadridSpain.

The khettaras constitute a hydraulic system for mobilising water by gravity from the water table to the surface to irrigate felds in *** system,which has been fairly widespread in North Africa,in particular in Algeria(foggara)and Morocco(khettaras),was introduced several centuries ago in the oases of southeastern Morocco and has contin‑ued to operate despite various natural and anthropic *** on these ingenious and millennial hydraulic systems,successive civilisations living in these environments have been able to establish laws and regulations for the management and mobilisation of natural resources,especially ***,to get the most out of these systems,users have had to abide by rules(Al Orf/Azref)designed to protect,promote,and care for the systems to enhance their *** hydraulic systems have declined in recent years,notably due to extensive groundwater pumping,climate variability(severe droughts),and the local population’s disinterest for this type of ***,we have unfortunately witnessed the loss of a thousand-year-old local ancestral know-how that had been developed by diferent succeeding civilisations in the *** initiatives(2008–2011)have been undertaken by the Moroccan government for the restoration and development of some abandoned khettaras in the Taflalet Oasis so that they could be utilised in the development of an oasis-based cultural tourism and integrated in a tourist circuit known as *** initiative,still in its infancy,has constituted an alternative and a fairly encouraging development for this national and world heritage.

关键词： Taflalet oasis Interactions society-environment Integrated water management Water civilisation

Morphological, Structural, Thermal and Tensile Properties of High Density Polyethylene Composites Reinforced with Treated Argan Nut Shell Particles

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Journal of Bionic Engineering 2015年第1期12卷 129-141页

作者： Hamid Essabir Mounir EI Achaby EI Moukhtar Hilali Rachid Bouhfid AbouEIkacem Qaiss Moroccan Foundation for Advanced Science Innovation and Research (MAScIR) Institute of Nanomaterials and Nanotechnology (NANOTECH) Laboratory of Polymer Processing Rabat Morocco National School of Applied Sciences Ibn Zohr University Laboratory Mechanics Processes Energy and Environment Agadir Morocco

High Density Polyethylene （HDPE） composites reinforced with treated bio-filler from Argan-Nut Shell （ANS） at various filler contents are prepared by extrusion and injection molding processes. The microstructures of the composites are charac- terized by Fourier Transform Infrared Spectroscopy （FTIS） and Scanning Electron Microscopy （SEM）; the thermal stability is analyzed by Thermogravimetric Analysis （TGA）, and their mechanical properties are investigated by dynamical mechanical analysis and rheological testing. The morphological and structural results indicate an improvement in adhesion between the ANS fillers and HDPE matrix upon alkali treatment. The mechanical properties of the composites show a significant increase in young＇s modulus with the addition of filler, a gain of 58% is marked compared to neat polymer, Thermal analysis reveals that the incorporation of bio-filler in polymer results in a decrease in decomposition temperatures. This research offers an ecological alternative to upgrade the valorization of abundant and unexploited Moroccan resources. In addition, the possibility of finding uses for ANS in composite manufacturing will help open new markets for what is normally considered waste or for use in low value products.

关键词： argan tree argan nut shell particles polymer composite melt extrusion mechanical properties

GUIDED WAVES IN MULTILAYERED PLATES: AN IMPROVED ORTHOGONAL POLYNOMIAL APPROACH

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Acta Mechanica Solida Sinica 2014年第5期27卷 542-550页

作者： Jiangong Yu J.E.Lefebvre L.Elmaimouni School of Mechanical and Power Engineering Henan Polytechnic University Department of Civil Engineering University of Siegen Univ Lille Nord de France F-59000 Lille France UVHC IEMN-DOAE F-59313 Valenciennes Cedex 9 France CNRS UMR 8520 F-59650 Villeneuve d’Ascq France ERSITA Faculte Polydisciplinaire d’Ouarzazate Univ. Ibn Zohr 45000 Ouarzazate Morocco LMTI Faculte des Sciences d’Agadir Universite Ibn Zohr BP 28/S Agadir Morocco

Conventional orthogonal polynomial approach can solve the multilayered plate only when the material properties of two adjacent layers do not change significantly. This paper de- veloped an improved orthogonal polynomial approach to solve wave propagation in multilayered plates with very dissimilar material properties. Through numerical comparisons among the exact solution, the results from the conventional polynomial approach and from the improved poly- nomial approach, the validity of the improved polynomial approach is illustrated. Finally, it is shown that the conventional polynomial approach can not yield correct continuous normal stress profiles. The improved orthogonul polynomial approach has overcome this drawback.

关键词： multilayered plate orthogonal polynomial dispersion curves stress profiles

The Phytodepuration of Wastewater for Tourism Facilities in Rural Areas: The Atlas Kasbah Ecolodge—A Pilot Site in the Argan Biosphere Reserve

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Journal of Environmental Protection 2014年第10期5卷 819-825页

作者： Hassan Aboutayeb Belkacem Kabbachi Abdelkrim Ezaidi Department of Earth Sciences Ibn Zohr University Agadir Morocco

In recent years, rural tourism has developed a lot and especially in the Souss Massa Draa region, in the South West of Morocco. The need to implement an eco-friendly sewage treatment has grown accordingly to resolve the wastewater issue. In this context, a pilot project of planted filters has been achieved in the Atlas Kasbah Ecolodge. During 3 years, the water purification performance and its compliance with the requirements of environmental management were assessed. The objective was to find an eco-friendly and affordable alternative to noncompliant ditches and sumps found in the rural areas of Morocco. The monitoring of physicochemical parameters of treated wastewater has revealed a perfect adaptation of the system to the needs of rural tourism facilities both in terms of efficiency and in terms of integration into the natural environment. Thus, such a technique could be spread in remote areas.

关键词： Sanitation Biofilter Treatment Environmental Management Rural Tourism Facility Morocco

Simple and Multi Linear Regression Model of Verbs in Quran

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American Journal of Computational Mathematics 2018年第1期8卷 68-77页

作者： Abdelkrim El Mouatasim Faculty of Polydisciplinary Ouarzazate (FPO) Ibn Zohr University Ouarzazate Morocco

This paper mainly presented a good simple and multi-linear regression model of verbs in the Quran book. This model, gives an analysis for the influence to frequency of words with the form (—un, ---) made by the frequency of plural present verbs (t—un, ---) or (y—un, ---), and models, and the relationship between independent variables and dependent variable by fitting a linear equation to the observed data with simple linear regression model. The matlab function is used for finding the parameters of the linear regression model and plotting the fits. The results show that the parameters of the model are one vector (1, 1) and mean of dataset is (6, 7). Its corresponding to the verb with input is frequency of the verb they enter and the frequency of enter (yadkolun ?dakilun), also other 17 points exist in the line and in the dataset of 387 verbs and their derivate verbs in Quran. The name of Allah () showed when we use tree variables and plot it in 3D with option “Show Text” for a multi regression model.

关键词： Linear Regression Text Mining Quran Statistics Matlab Arabic Grammar Optimization Computation Linguistics

Characterization and Classification of Rocks with Lamb Modes

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International Journal of Geosciences 2012年第3期3卷 565-573页

作者： Dris El Abassi Bouazza Faiz Abderahmane Ibhi Idris Aboudaoud Equip Petrology Metallogeny and Materials Department of Geology University Ibn Zohr Agadir Morocco Metrology Laboratory and Information Treatment Department of physics University Ibn Zohr Agadir Morocco

The nondestructive investigation by ultrasound has become a fundamental tool for characterizing rocks. We applied this technique for characterizing samples of rocks. The later had been members of the following three big families of geogical classification: magmatic rocks, metamorphic rocks, sedimentary rocks. The method usually used is based on the measurement of ultrasound parameters, i.e. the longitudinal and transversal propagation velocities. The measurement of these parameters allows to determine the mechanical properties of each rock. These studies do not allow to find the three big axes of the rocks. In this work we show for each rock his corresponding ultrasonic signature by the use of his experimentally determined Lamb dispersion curves. The obtained results put in evidence that the descending slope of the Lamb modes is a reliable and efficient criterion for classifying rocks by ultrasound. This is an adequate solution for a good classification of rocks. It gives a high precision, it is reliable and quick and last not least cheap.

关键词： Ultrasound Lamb Waves Nondestructive Investigation Magmatic Rocks Metamorphic Rocks Sedimentary Rocks