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Enhancing fault-clearing algorithm for renewable-energy-based distribution systems using artificial neural networks

Clean Energy 2024年第5期8卷 97-116页

作者： Rania G.mohamed m.A.Ebrahim shady h.E.Abdel Aleem Electrical Engineering Department Institute of Aviation Engineering and TechnologyGiza12658Egypt Electrical Engineering Department Faculty of Engineering at ShoubraBenha UniversityCairo11629Egypt

Integrating small and large-scale photovoltaic(PV)solar systems into electrical distribution systems has become mandatory due to increased electricity bills and the concern for limiting greenhouse ***,the reliable and efficient operation of PV-based distribution systems can be confronted by the intermittence and high variability of solar sources and their consequential *** this regard,this article suggests a moderated fault-clearing strategy based on the incremental conductance–maximum power point tracking(IC–mPPT)technique and artificial neural networks(ANNs)to enhance fault detection,localization,and restoration pro-cesses in PV-based distribution *** proposed strategy leverages IC–mPPT to ensure optimal power generation from the PV solar system,even in the presence of *** tracking the maximum power point,the algorithm maintains the performance of the system and mitigates against the impact of faults on the output ***,an ANN is employed to improve fault detec-tion and localization *** developed ANN-based moderated fault-clearing strategy is trained using historical data and fault scenarios,enabling it to recognize fault patterns and make informed decisions through extensive simulations and comparisons with traditional fault-clearing *** accomplish this study,benchmarks in PV-based distribution systems are constructed and em-ployed using the mATLAB®/Simulink®software ***,to validate the efficacy of the developed ANN-based moderated fault-clearing strategy,a real case study of a 1-mw PV-based distribution system in an industrial field located in Giza governorate,Egypt,is tested and *** obtained results demonstrate the effectiveness of the IC–mPPT and ANN-based moderated fault-clearing strategy in achieving faster fault detection,precise fault localization,and efficient restoration in PV solar-based dis-tribution systems while preserving maximum power extraction under small and larg

关键词： photovoltaic solar systems fault-clearing algorithm incremental conductance renewable energy artificial neural network maximum power point tracking

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Risk Factors for Cardiovascular Disease among hotel workers, Bohicon, Benin

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Occupational Diseases and Environmental medicine 2024年第2期12卷 130-141页

作者： mênonli Adjobimey Rose mikponhoué eméline Gbaguidi Esdras hountohotegbè hélène Sacca Paul Ayélo Vikkey Antoine hinson Unité de Recherche et d&#8217Enseignement en Sant&#233 au Travail et Environnement FSS Cotonou Cotonou Benin Service de Santé au Travail du Centre National Hospitalier Universitaire de Pneumo Phtisiologie de Cotonou Cotonou Benin Laboratoire d’ Epid&#233miologie des Maladies Chroniques et Neurologiques FSS Cotonou Benin

Introduction: Non-communicable diseases (NCDs) are on the increase in several sectors of activity. The aim of the study was to determine the frequencies of cardiovascular risk factors (CVRF) and factors associated with hypertension among hotel workers in the city of Bohicon. methods: This was a descriptive and analytical cross-sectional study conducted in the period from December 2018 to January 2019. The variables studied were sociodemographic, occupational, anthropometric and behavioral. Participant recruitment was exhaustive. A standardized questionnaire inspired by the STEPS-whO questionnaire was used for data collection. After the descriptive analysis, a bivariate analysis was performed using Pearson’s Chi-square test or Fisher’s test at the 5% threshold. Results: A total of 101 workers, 53 (52.47%) of them male, participated in the study. The mean age was 30.60 ± 8.20 years, with extremes of 18 and 55 years. The frequencies of the main risk factors were: 68.32% sitting position > 6 hours/day;38.61% shift work;21.78% high psychological demand, 82.18% low decision latitude, 24.75% low social support, 21.78% occupational stress;7 (6.93%) harmful alcohol consumption;6.93% tobacco consumption;48.51% insufficient physical activity;98.02% insufficient fruit and vegetable consumption;59.41% overweight;14.85% hTA. Factors associated with hypertension were: sex, age and marital status. Conclusion: Occupational factors need to be taken into account when assessing CVRFs. NCD control programs are needed in all sectors of activity. A larger study is needed in the hotel sector.

关键词： FDRCV Occupational Factors hypertension hotels Benin

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Sorption of certain lanthanides by kieselguhr loaded with Cyanex 572 from sulfate medium

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Journal of Rare Earths 2020年第3期38卷 299-305页

作者： sh.sh.emam m.S.Gasser N.E.El-hefny w.h.mahmoud h.F.Aly hot Laboratories Centre Atomic Energy AuthorityCairo 13759Egypt Department of Chemistry Faculty of ScienceAin Shams UniversityCairoEgypt

Kieselguhr for chromatography was loaded with Cyanex 572 extractant and characterized using X-ray diffraction(XRF),scanning electron microscopy(Sem),Fourier transform infra-red(FT-IR),and thermal *** of some heavy lanthanides together with yttrium by the prepared kieselguhr/Cy-572 sorbent was investigated by batch experiment in terms of initial metal ions concentrations,volume to solid mass ratio(V/m),sulfuric acid concentration as well as *** sorption equilibrium of Cy-572 loaded kieselguhr was satisfactorily explained by the pseudo second-order kinetic model and Langmuir isotherm ***,the values of thermodynamic parameters △G°,△h°,and △S°at25℃of the studied metal ions show that the process is spontaneous and endothermic in nature.2.0 mol/L hNO3 is promising to desorb these metal ions.

关键词： Sorption Cyanex 572 Lanthanides Kieselguhr Sulfate medium Rare earths

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Comparative studies on Y(Ⅲ)and Dy(Ⅲ)extraction from hydrochloric and nitric acids by Cyanex 572 as a novel extractant

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Journal of Rare Earths 2018年第12期36卷 1342-1350页

作者： N.E.El-hefny m.S.Gasser sh.sh.emam w.h.mahmoud h.F.Aly hot Laboratories Centre Atomic Energy Authority Faculty of Science Ain Shams University

Extraction of Y(III) and Dy(III) from hydrochloric and nitric acids by Cy-572 in kerosene was studied. The factors affecting the extraction were separately investigated. The stoichiometry of the extracted species was deduced on the basis of slope analysis method. Evaluation of extraction equilibrium and stripping investigation was studied as well as saponification effect of Cy-572. The composition of the extracted metal species in the organic phase was found to be [mA·(hA)] for Y(III) or Dy(III) in both media.1.0 mol/L hCI is the best stripping agent for each metal ion from the studied acidic media in one *** Cy-572 does not exhibit any selectivity towards the extraction of Y(III) or Dy(III) from both hCI and hNOsolutions. Based on the obtained results, the data were compared and the separation feasibility between lanthanides and Y(III) in the two media was discussed.

关键词： Extraction Cyanex-572 Yttrium Lanthanides Separation factor Saponification

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Inverse heat Transfer Problem of Thermal Contact Conductance Estimation in Periodically Contacting Surfaces

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Journal of Thermal Science 2009年第2期18卷 150-159页

作者： m.h.shojaeefard K.Goudarzi m.sh.mazidi Dept. of mechanical Engineering Iran University of Science and Technology

The problems involving periodic contacting surfaces have different practical applications. An inverse heat conductionproblem for estimating the periodic Thermal Contact Conductance (TCC) between one-dimensional, constantproperty contacting solids has been investigated with conjugate gradient method (CGm) of function *** method converges very rapidly and is not so sensitive to the measurement errors. The advantage of thepresent method is that no a priori information is needed on the variation of the unknown quantities, since the solutionautomatically determines the functional form over the specified domain. A simple, straight forward techniqueis utilized to solve the direct, sensitivity and adjoint problems, in order to overcome the difficulties associatedwith numerical methods. Two general classes of results, the results obtained by applying inexact simulatedmeasured data and the results obtained by using data taken from an actual experiment are presented. In addition,extrapolation method is applied to obtain actual results. Generally, the present method effectively improves theexact TCC when exact and inexact simulated measurements input to the analysis. Furthermore, the results obtainedwith CGm and the extrapolation results are in agreement and the little deviations can be negligible.

关键词： thermal contact inverse problem conjugates gradient method

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Experimental and numerical study on plasma nitriding of AISI P20 mold steel

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International Journal of minerals,metallurgy and materials 2016年第9期23卷 1065-1075页

作者： N.Nayebpashaee h.Vafaeenezhad sh.Kheirandish m.Soltanieh materials Processing Simulation Laboratory(mPS-LAB) School of Materials and Metallurgical EngineeringIran University of Science and Technology(IUST) School of materials and metallurgical Engineering Iran University of Science and Technology(IUST)

In this study, plasma nitriding was used to fabricate a hard protective layer on AISI P20 steel, at three process temperatures（450℃, 500℃, and 550℃） and over a range of time periods（2.5, 5, 7.5, and 10 h）, and at a fixed gas N2：h2 ratio of 75vol%：25vol%. The morphology of samples was studied using optical microscopy and scanning electron microscopy, and the formed phase of each sample was determined by X-ray diffraction. The elemental depth profile was measured by energy dispersive X-ray spectroscopy, wavelength dispersive spectroscopy, and glow dispersive spectroscopy. The hardness profile of the samples was identified, and the microhardness profile from the surface to the sample center was recorded. The results show that ε-nitride is the dominant species after carrying out plasma nitriding in all strategies and that the plasma nitriding process improves the hardness up to more than three times. It is found that as the time and temperature of the process increase, the hardness and hardness depth of the diffusion zone considerably increase. Furthermore, artificial neural networks were used to predict the effects of operational parameters on the mechanical properties of plastic mold steel. The plasma temperature, running time of imposition, and target distance to the sample surface were all used as network inputs; Vickers hardness measurements were given as the output of the model. The model accurately reproduced the experimental outcomes under different operational conditions; therefore, it can be used in the effective simulation of the plasma nitriding process in AISI P20 steel.

关键词： tool steel plasma nitriding sputtering neural networks

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Sliding wear Behavior of a Grey Cast Iron Surface Remelted by TIG

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Journal of materials Science & Technology 2009年第5期25卷 622-628页

作者： h.mohamadzadeh h.Saghafian sh.Kheirandish Department of metallurgy and materials Engineering Iran University of Science and TechnologyTehranIran

The sliding wear behavior of a grey cast iron surface remelted by tungsten inert gas （TIG） was studied and compared with the unremelted one in the current work. To evaluate the wear behavior a Pin-on-Disk wear test machine was used. Pins which were prepared from the samples with the remelted layers of different thicknesses of 1.2, 1.8, 2.5 and 3 turn were worn on an AISID3 steel counterface having a hardness of 63hRC under the applied loads of 54, 76 and gg N at a constant sliding velocity of 0.45 m/s. Scanning electron microscopy （Sem） equipped with energy dispersive X-ray analysis （EDS） and X-ray diffraction （XRD） techniques were used to characterize worn surface and subsurface and also wear debris obtained from the wear tests under different test conditions. Results showed that surface remelted grey cast iron have better wear properties for all applied normal loads in comparison with unremelted ones. microscopic studies on the worn surfaces and subsurfaces of samples revealed that dominant wear mechanism for surface remelted samples was mild oxidative, while it was severe for unremelted samples. Increasing remelted layer thickness and then forming grosser microstructure lead to a decline of wear properties, whereas lower thickness of remelted layer with finer microstructure due to having higher cooling rate through remelting process can withstand better against wear.

关键词： Grey cast Iron Surface remelted Tungsten inert gas (TIG) wear

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Dry Sliding Oxidative wear in Plain Carbon Dual Phase Steel

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Journal of Iron and Steel Research International 2007年第4期14卷 43-48页

作者： V Abouei h Saghafian sh Kheirandish Department of metallurgy and materials Engineering Iran University of Science and TechnologyNarmak 16844TehranIran

To investigate the tribological potential of the dual phase （DP） steel as a wear resistant material, the wear and the friction characteristics of this steel, which consists of hard martensite islands embedded in a ductile ferrite matrix, have been investigated and compared with those observed in plain carbon hardened （h） steel that has the same carbon content of 0.2%. Dry sliding wear tests have been carried out using a pin-on-disk wear testing machine at different normal loads of 21.3 N, 28. 5 N, 35.7 N, and 42.6 N and at a constant sliding velocity of 1.20 m/s. The analysis of surface and wear debris of samples showed that the wear mechanism was mainly mild oxidative. The friction and the wear rate of the h steel and the DP Steel have been explained with respect to the microstructure and the wear mechanism.

关键词： dual phase steel wear microstructure heat treatment

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Study of Sintering Behaviour and Electrical Conductivity of Cr-Zn-Fe-O System

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Journal of materials Science & Technology 1999年第1期15卷 79-82页

作者： hanna, A.A. Khalil, m.sh. Saleh, h.I. Ali, A.F. Inorganic Chemistry Department National Research Centre Dokki Cairo Egypt

A series of chemical composition based on Cr, Fe and O with Zn as a partially substituting ion has been prepared in the general formula Zn//xCr//1// minus //xFe//2O by coprecipitation method using Nh//4Oh as the precipitating agent at ph equals 10.3. The prepared samples were identified by both thermal analysis (DTA and TGA) and X-ray diffraction. It was found that no single phase is obtained for any of the studied compositions but a mixture of different phases is observed, depending on the molar percentage of zinc ion substitution as well as on the sintering temperature. The temperature dependence of the electrical conductivity, sigma , of the prepared samples is plotted between 25 and 680 degree C. It was observed that the electrical conductivity increases with temperature for both samples with x equals 0.00 and 0.80 Zn ion content while it is nearly temperature independent for samples with intermediate Zn concentration x equals 0.2 and 0.5 mol fraction. The activation energy, E//a, calculated from the linear relation, lg sigma -1000/T for the final mixtures (sintered at 1300 degree C) was calculated. (Edited author abstract) 16 Refs.

关键词： Chromium compounds

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Landscape of global urban environmental resistome and its association with local socioeconomic and medical status

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Science China(Life Sciences) 2024年第6期67卷 1292-1301页

作者： Jun wu Yige hu michael h Perlin David Danko Jun Lu manuela Oliveira Johannes werner maria m Zambrano maria A Sierra Olayinka O Osuolale Paweł Łabaj Nicolás Rascovan Nur hazlin hazrin-Chong Soojin Jang haruo Suzuki marina Nieto-Caballero Bharath Prithiviraj Patrick K h Lee Agnieszka Chmielarczyk Anna Różańska Yongxiang Zhao Lan wang Christopher E mason Tieliu shi Center for Bioinformatics and Computational Biology and the Institute of Biomedical SciencesSchool of Life SciencesEast China Normal UniversityShanghai 200241China Department of Biology Program on Disease EvolutionUniversity of LouisvilleLouisville 40292USA weill Cornell medicine New York 10065USA The Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine New York 10065USA Department of Pulmonary medicine Shanghai Chest HospitalShanghai Jiao Tong UniversityShanghai 200025China i3S-Instituto de Investiga玢o e Inova玢o em Saúde Universidade do PortoPorto 4050-290Portugal Ipatimup-Instituto de Patologia e Imunologia molecular da Universidade do Porto Porto 4200-465Portugal Departamento de Biologia Faculdade de CiênciasUniversidade do PortoPorto 4050-290Portugal high Performance and Cloud Computing Group Zentrum für Datenverarbeitung(ZDV)Eberhard Karls University of TübingenW鋍hterstra遝7672074TübingenGermany Corporación Corpogen Research Center Bogotá110311Colombia Applied Environmental metagenomics and Infectious Diseases Research(AemIDR) Department of Biological SciencesElizade UniversityIlara-Mokin 340271Nigeria maopolska Centre of Biotechnology Jagiellonian UniversityKraków 30-005Poland Aix-marseille Université Mediterranean Institute of OceanologyUniversitéde ToulonCNRSIRDUM 110Marseille 83041France Department of Biological Sciences and Biotechnology Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia43600 UKM BangiSelangor Institut Pasteur Korea Seoul 13488Republic of Korea Faculty of Environment and Information Studies Keio UniversityFujisawaKanagawa 252-0882Japan University of Colorado at Boulder CivilEnvironmental and Architectural DepartmentBoulder 80303USA Brooklyn College of the City University of New York Brooklyn 11210USA School of Energy and Environment City University of Hong KongHong Kong 999077China Department of microbiology Faculty of MedicineJagiellonian UniversityKraków 30-005Poland Biological Targeting Diagnosis and The

Antimicrobial resistance(AmR)poses a critical threat to global health and development,with environmental factors—particularly in urban areas—contributing significantly to the spread of antibiotic resistance genes(ARGs).however,most research to date has been conducted at a local level,leaving significant gaps in our understanding of the global status of antibiotic resistance in urban *** address this issue,we thoroughly analyzed a total of 86,213 ARGs detected within 4,728 metagenome samples,which were collected by the meta SUB International Consortium involving diverse urban environments in 60 cities of 27 countries,utilizing a deep-learning based *** findings demonstrated the strong geographical specificity of urban environmental resistome,and their correlation with various local socioeconomic and medical *** also identified distinctive evolutionary patterns of ARG-related biosynthetic gene clusters(BGCs)across different countries,and discovered that the urban environment represents a rich source of novel *** study provides a comprehensive overview of the global urban environmental resistome,and fills a significant gap in our knowledge of large-scale urban antibiotic resistome analysis.

关键词： urban environment metagenome antibiotic resistance resistance diversity biosynthetic gene clusters

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