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Journal of Hydrodynamics 2013年第5期25卷 788-804页

作者： TRAN KHANH Toan OUAHSINE Abdellatif NACEUR Hakim EL WASSIFI Karima Laboratoire Roberval Université de Technologie de Compiègne Laboratoire LAMIH Université de Valenciennes université cadi ayyad Faculté des Sciences et Techniques

In this paper, a numerical method based on a coupling between a mathematical model of nonlinear transient ship manoeuvring motion in the horizontal plane and Mathematical Programming （MP） techniques is proposed. The aim of the proposed procedure is an efficient estimation of optimal ship hydrodynamic parameters in a dynamic model at the early design stage. The proposed procedure has been validated through turning circle and zigzag manoeuvres based on experimental data of sea trials of the 190 000- dwt oil tanker. Comparisons between experimental and computed data show a good agreement of overall tendency in manoeuvring traiectories.

关键词： ship manoeuvrability hydrodynamics coefficients nonlinear transient dynamics sensitivity analysis mathematical pro- gramming

Endophytic actinobacteria of medicinal plant Aloe vera: Isolation, antimicrobial, antioxidant, cytotoxicity assays and taxonomic study

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Asian Pacific Journal of Tropical Biomedicine 2018年第10期8卷 513-518页

作者： Ahmed Nafis Ayoub Kasrati Asma Azmani Yedir Ouhdouch Lahcen Hassani Laboratory of Biology and Biotechnology of Microorganisms Faculty of Sciences SemlaliaCadi Ayyad University Department of Biology Faculty of Sciences SemlaliaCadi Ayyad University

Objective: To explore the new sources of novel bioactive compounds having pharmaceutical and agricultural interest and to search the endophytic actinobacteria from medicinal plants. Methods: NAF-1 an endophyte actinobacteria was isolated from leaves of medicinal plant Aloe vera collected in Marrakesh, Morocco using Bennett agar as selective medium. NAF-1 was tested for its antimicrobial activity against five pathogenic bacteria such as Staphylococcus aureus PIC 53156, Micrococcus luteus ATCC381, Bacillus subtilis ATCC 14579, Pseudomonas aeruginosa DSM 50090 and Escherichia coli ATCC 8739 and four human clinic fungi belonging to the Candida, Aspergillus and Microsporum genera. Several antioxidant activities were studied such as DPPH free radical scavenging, β-carotene and linoleic acid and reducing power assays. The total of phenol and flavonoid was also calculated. Using Artemia salina shrimp assay, the cytotoxicity of NAF-1 crude extract was determined. Results: The results revealed that the actinobacteria showed a high activity(≥20 mm) against only Gram positive bacteria but it had a moderate activity(between 13 and 15 mm) against Human clinic fungi. The isolate also exhibited a LD50 of 14.20 μg/mL in the cytotoxicity assay. The result showed that the crude extract presented an interesting free radical-scavenging activity with IC50 value of(5.58 ± 0.26) μg/mL and a high value of phenolic and flavonoid compounds with(15.41 ± 0.18) μg GAE/mg extract and(11.41± 0.06) μg QE/mg extract respectively. Moreover, the taxonomic position of our endophyte actinobacteria using the morphological and physiological criteria and using 16 S r RNA gene sequence(polyphasic approach) showed that the NAF-1 isolate was similar to Streptomyces hydrogenans which was never described as an endophyte actinobacteria. Conclusions: This isolated strain appears promising resources of bioactive agents and can be exploited to produce therapeutic agents active against pathogenic disease.

关键词： Actinobacteria Medicinal plant Aloe vera Antimicrobial activity Cytotoxicity Antioxidant assays Molecular identification

Analysis of the Impact of the Blazhko Effect Both on the Van Hoof Effect and Radial Velocity Amplitude in the Star RR Lyr

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Research in Astronomy and Astrophysics 2024年第6期24卷 253-272页

作者： Y.El jariri F.L.Sefyani A.Benhida Z.Benkhaldoun K.Kolenberg K.Chafouai A.Habib M.Sabil Observatoire de l'Oukaimeden LPHEAFSSMUniversitéCadi AyyadMarrakech2390Morocco Observatoire de l'Oukaimeden LPHEAFSTGUniversitéCadi AyyadMarrakech549Morocco Département de physique Universitéd'Anvers Avenue Groenenborger 171Anvers2020Belgium LICPM ENSA-BMUniversitéSultan Moulay SlimaneBeni-Mellal23020Morocco

The Van Hoof effect is a phase shift existing between the radial velocity curves of hydrogen and metallic lines within the atmosphere of pulsating *** this article,we present a study of this phenomenon through the spectra of the brightest pulsating star RR Lyr of RR Lyrae stars recorded for 22 *** based ourselves,on the one hand,on 1268 spectra(41 nights of observation)recorded between the years 1994 and 1997 at the Observatory of Haute Provence(OHP,France)previously observed by Chadid and Gillet,and on the other hand on 1569 spectra(46nights of observation)recorded at our Oukaimeden Observatory(Morocco)between 2015 and *** this study,we have detected information on atmospheric dynamics that had not previously been ***,the Van Hoof effect which results in a clear correlation between the radial velocities of hydrogen and those of the metallic lines has been observed and analyzed at different Blazhko phases.A correlation between the radial velocities of different metallic lines located in the lower atmosphere has been observed as *** the first time,we were able to show that the amplitude of the radial velocity curves deduced from the lines of hydrogen and that of FeⅡ(λ4923.921?)increases toward the minimum of the Blazhko cycle and decreases toward the maximum of the same Blazhko ***,we found that the Van Hoof effect is also modulated by the Blazhko ***,toward the minimum of the Blazhko cycle the Van Hoof effect is more visible and at the maximum of the Blazhko cycle,this effect is *** also observed the temporal evolution of the amplitudes of the radial velocities of the lower and upper *** observed over a long time,we can interpret it as a function of the Blazhko phases.

关键词： stars:atmospheres stars:variables:RR Lyrae shock waves techniques:spectroscopic techniques:radial velocities stars:individual(RR Lyr)

Mc Kean–Vlasov BSDEs with Locally Monotone Coefficient

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Acta Mathematica Sinica,English Series 2023年第7期39卷 1414-1424页

作者： Brahim BOUFOUSSI Soufiane MOUCHTABIH LIBMA Faculty of Sciences SemlaliaCadi Ayyad University2390 MarrakeshMorocco École Supérieure de Technologie d'El Kelaa des Sraghna UniversitéCadi AyyadRoute de Béni Mellal Km 8 B.P.104El Kelaa des SraghnaMorocco

We consider a McKean Vlasov backward stochastic differential equation(MVBSDE) of the form Y_(t)=-F(t,Y_(t),Z_(t),[Y_(t)]) dt+Z_(t) dB_(t),Y_(T)=ξ,where [Y_(t)] stands for the law of Y,.We show that if F is locally monotone in y,locally Lipschitz with respect to z and law's variable,and the monotonicity and Lipschitz constants κ_(n),L_(n) are such that L_(n)^(2)+κ_(n)^(+)=O(log(N)),then the MVBSDE has a unique stable solution.

关键词： McKean–Vlasov BSDE locally monotone coefficient stability

Computational study of inverse ferrite spinels

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Chinese Physics B 2019年第5期28卷 305-311页

作者： A EL Maazouzi R Masrour A Jabar M Hamedoun Laboratory of Materials Processes Environment and Quality Cadi Ayyad University National School of Applied Sciences Institute of Nanomaterials and Nanotechnologies

The magnetic properties of inverse ferrite Fe_(3+) Fe_(3+)Co_(2+) O^(2-)_4, Fe^(3+) Fe^(3+)Cu^(2+) O^2_(-4), Fe^(3+) Fe^(3+)Fe^(2+) O^2_(-4),and Fe^(3+) Fe^(3+)Ni^(2+) O^(2-)_4spinels have been studied using Monte Carlo simulation. We have also calculated the critical and Curie Weiss temperatures from the thermal magnetizations and inverse of magnetic susceptibilities for each *** hysteresis cycles have been found for the four systems. Finally, we found the critical exponents associated with magnetization, magnetic susceptibility, and external magnetic field. Our results of critical and Curie Weiss temperatures are similar to those obtained by experiment results. The critical exponents are similar to those of known 3 D-Ising model.

关键词： inverse ferrites spinels Monte Carlo simulation critical and Curie Weiss temperatures magnetic hysteresis cycles critical exponents

Thermal Analysis of a Phase Change Material Based Heat Sink for Cooling Protruding Electronic Chips

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Journal of Thermal Science 2009年第3期18卷 268-275页

作者： Mustapha FARAJI Hamid EL QARNIA EI Khadir LAKHAL Fluids Mechanic and Energetic Laboratory Automatic Environment and Transfer Process Laboratory Cadi Ayyad University Faculty of Sciences Semlalia Department of Physics

This work aims to numerically study the melting natural convection in a rectangular enclosure heated by three discreet protruding electronic chips. The beat sources generate heat at a constant and uniform volumetric rate. A part of the power generated in the heat sources is dissipated to a phase change material （PCM, n-eicosane with melting temperature, Tm = 36℃）. Numerical investigations were carded out in order to examine the effects of the plate thickness on the maximum temperature of electronic components, the percentage contribution of plate heat conduction on the total removed heat and temperature profiles in the plate. Con＇elations for the dimensionless secured working time （time to reach the threshold temperature, Tcr = 75℃） and the corresponding liquid fraction were derived.

关键词： Phase change material protruding electronic component natural convection

Interpolation in the Automorphism Group of a Polynomial Ring

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Algebra Colloquium 2020年第3期27卷 587-598页

作者： M'hammed El Kahoui Najoua Essamaoui Mustapha Ouali Department of Mathematics Faculty of Sciences Semlalia Cadi Ayyad UniversityP.O.Box 2390MarrakeshMorocco

Let R be a commutative ring with unity and SA_(n)(R)be the group of volumepreserving automorphisms of the polynomial R-algebra R^([n]).Given a proper ideal a of R,we address in this paper the question of whether the canonical group homomorphism SA_(n)(R)→SA_(n)(R/α)is *** an application,we retrieve and generalize,in a unified way,several known results on residual coordinates in polynomial rings.

关键词： polynomial automorphism coordinate residual coordinate

^238U and^232Th concentrations measured in different medical drugs by using solid-state nuclear track detectors and resulting radiation doses to the skin of patients

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Nuclear Science and Techniques 2016年第3期27卷 11-22页

作者： m.a.misdaq a.matrane Nuclear Physics and Techniques Laboratory Faculty of Sciences SemlaliaUniversity of Cadi AyyadBP.239040000 MarrakechMorocco URAC-15 Research Unit Associated to the CNRST RabatMorocco Nuclear Medicine Service Mohamed VI University Hospital CentreFaculty of Medicine and PharmacyUniversity of Cadi Ayyad40000 MarrakechMorocco

Urban populations in Morocco receive free medical drugs as prescribed by doctors in district health *** explore the exposure pathway of ^(238)U and^(232)Th and their decay products on the skin of patients,these radionuclides were measured in various medical drugs by using solid-state nuclear track detectors(SSNTDs).The measured concentrations range of ^(238)U and ^(232)Th in the medical drug samples of interest vary from(4.3±0.3) to(11.1±0.7) mBq 1^(-1) and(0.49±0.03) to(1.3±0.1)mBq 1^(-1),respectively.A new dosimetric model,based on the concept of specific alpha-dose and alpha-particle residual energy,was developed for evaluating radiation doses to skin following the application of different medical drugs by *** maximum total equivalent effective dose to skin due to the ^(238)U and ^(232)Th series from cutaneous application of different medical drugs by patients was found to be 2.8 mSv year^(-1) cm^(-2).

关键词：固体核径迹探测器药物应用辐射剂量皮肤患者浓度测定放射性核素城市人口

Enhanced IDS with Deep Learning for IoT-Based Smart Cities Security

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Tsinghua Science and Technology 2024年第4期29卷 929-947页

作者： Chaimae Hazman Azidine Guezzaz Said Benkirane Mourade Azrour Higher School of Technology Essaouira Cadi Ayyad UniversityMarrakesh 81000Morocco Faculty of Sciences and Technologies Moulay Ismail UniversityErrachidia 52000Morocco

Cyberattacks against highly integrated Internet of Things (IoT) servers, apps, and telecoms infrastructure are rapidly increasing when issues produced by IoT networks go unnoticed for an extended period. IoT interface attacks must be evaluated in real-time for effective safety and security measures. This study implements a smart intrusion detection system (IDS) designed for IoT threats, and interoperability with IoT connectivity standards is offered by the identity solution. An IDS is a common type of network security technology that has recently received increasing interest in the research community. The system has already piqued the curiosity of scientific and industrial communities to identify intrusions. Several IDSs based on machine learning (ML) and deep learning (DL) have been proposed. This study introduces IDS-SIoDL, a novel IDS for IoT-based smart cities that integrates long shortterm memory (LSTM) and feature engineering. This model is tested using tensor processing unit (TPU) on the enhanced BoT-IoT, Edge-IIoT, and NSL-KDD datasets. Compared with current IDSs, the obtained results provide good assessment features, such as accuracy, recall, and precision, with approximately 0.9990 recording time and calculating times of approximately 600 and 6 ms for training and classification, respectively.

关键词： intrusion detection LSTM IoT security ML DL TPU

ANALYSIS FOR THERMAL BEHAVIOR AND ENERGY SAVINGS OF A SEMI-DETACHED HOUSE WITH DIFFERENT INSULATION STRATEGIES IN A HOT SEMI-ARID CLIMATE

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Journal of Green Building 2017年第1期12卷 78-106页

作者： Issam Sobhy Abderrahim Brakez Brahim Benhamou Energy Processes Research Group LMFE(URAC 27)Faculty of Science SemlaliaCadi Ayyad UniversityMarrakechMorocco EnR2E laboratory National Center of Studies and Research on Water and Energy CNEREECadi Ayyad UniversityMarrakechMorocco

The purpose of this research is to assess thermal performance and energy saving of a residential building in the hot semi-arid climate of Marrakech(Morocco).The studied house is built as usual in Marrakech without any thermal insula-tion except for its external walls,facing East and West,which are double walls with a 5 cm air gap in between(“cavity wall”technique).The cavity wall effec-tive thermal conductivity was carefully calculated taking into account both radia-tion and convection heat *** results,obtained from winter and summer monitoring of the house,show well dampening of air temperature,thanks to its thermal ***,this temperature remained outside the standard thermal comfort zone leading to large cooling/heating ***-tion results indicate that the cavity wall contributes to an overall reduction of 13%and 5%of the house heating and cooling loads ***,the addition of XPS roof thermal insulation significantly enhances the heating and cooling energy savings to 26%and 40%respectively.

关键词： dynamic simulation monitoring cooling&heating load thermal insulation cavity wall energy saving