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Optimal Allocation of a Hybrid Wind Energy-Fuel Cell System Using Different Optimization Techniques in the Egyptian Distribution Network

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Energy and Power Engineering 2021年第1期13卷 17-40页

作者： Adel A. Abou El-Ela Sohir M. Allam nermine k. shehata Department of Electrical Engineering Faculty of Engineering Menoufia University Shebin El-Kom Egypt

This paper presents an optimal proposed allocating procedure for hybrid wind energy combined with proton exchange membrane fuel cell (WE/PEMFC) system to improve the operation performance of the electrical distribution system (EDS). Egypt has an excellent wind regime with wind speeds of about 10 m/s at many areas. The disadvantage of wind energy is its seasonal variations. So, if wind power is to supply a significant portion of the demand, either back.p power or electrical energy storage (EES) system is needed to ensure that loads will be supplied in reliable way. So, the hybrid WE/PEMFC system is designed to completely supply a part of the Egyptian distribution system, in attempt to isolate it from the grid. However, the optimal allocation of the hybrid units is obtained, in order to enhance their benefits in the distribution network.. The critical buses that are necessary to install the hybrid WE/ PEMFC system, are chosen using sensitivity analysis. Then, the binary Crow search algorithm (BCSA), discrete Jaya algorithm (DJA) and binary particle swarm optimization (BPSO) techniques are proposed to determine the optimal operation of power systems using single and multi-objective functions (SOF/MOF). Then, the results of the three optimization techniques are compared with each other. Three sensitivity factors are employed in this paper, which are voltage sensitivity factor (VSF), active losses sensitivity factor (ALSF) and reactive losses sensitivity factor (RLSF). The effects of the sensitivity factors (SFs) on the SOF/MOF are studied. The improvement of voltage profile and minimizing active and reactive power losses of the EDS are considered as objective functions. Back.ard/forward sweep (BFS) method is used for the load flow calculations. The system load demand is predicted up to year 2022 for Mersi-Matrouh City as a part of Egyptian distribution network. and the design of the hybrid WE/PEMFC system is applied. The PEMFC system is designed considering simplified m

关键词： Wind Energy System Proton Exchange Membrane Fuel Cell Binary Crow Search Algorithm Discrete Jaya Algorithm Binary Particle Swarm Optimization Technique

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Finite element modeling assumptions impact on seismic response demands of MRF-buildings

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Earthquak. Engineering and Engineering Vibration 2018年第4期17卷 821-834页

作者： shehata E Abdel Raheem Ahmed k.Abdel Zaher Ahmed MA Taha Civil Engineering Department Engineering College Taibah University Civil Engineering Department Faculty of Engineering Assiut University

Recent seismic events have raised concerns over the safety and vulnerability of reinforced concrete moment resisting frame ＂RC-MRF＂ buildings. The seismic response of such buildings is greatly dependent on the computational tools used and the inherent assumptions in the modelling process. Thus, it is essential to investigate the sensitivity of the response demands to the corresponding modelling assumption. Many parameters and assumptions are justified to generate effective structural finite element（FE） models of buildings to simulate lateral behaviour and evaluate seismic design demands. As such, the present study focuses on the development of reliable FE models with various levels of refinement. The effects of the FE modelling assumptions on the seismic response demands on the design of buildings are investigated. the predictive ability of a FE model is tied to the accuracy of numerical analysis; a numerical analysis is performed for a series of symmetric buildings in active seismic zones. The results of the seismic response demands are presented in a comparative format to confirm drift and strength limits requirements. A proposed model is formulated based on a simplified modeling approach, where the most refined model is used to calibrate the simplified model.

关键词： RC-MRF buildings design codes provisions seismic design finite element modeling modeling assumptions response demands

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Developed Fall Detection of Elderly Patients in Internet of Healthcare Things

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Computers, Materials & Continua 2023年第8期76卷 1689-1700页

作者： Omar Reyad Hazem Ibrahim shehata Mohamed Esmail k.rar College of Computing and Information Technology Shaqra UniversityP.O.Box 33Shaqra11961Saudi Arabia Faculty of Computers and Artificial Intelligence Sohag UniversitySohag82524Egypt Faculty of Engineering Zagazig UniversityZagazig44519Egypt Faculty of Electronic Engineering Menoufia UniversityMenouf32952Egypt

Falling is among the most harmful events older adults may *** the continuous growth of the aging population in many societies,developing effective fall detection mechanisms empowered by machine learning technologies and easily integrable with existing healthcare systems becomes *** paper presents a new healthcare Internet of Health Things(IoHT)architecture built around an ensemble machine learning-based fall detection system(FDS)for older *** to deep neural network.,the ensemble multi-stage random forest model allows the extraction of an optimal subset of fall detection features with minimal *** number of cascaded random forest stages is automatically *** study uses a public dataset of fall detection samples called SmartFall to validate the developed fall detection *** SmartFall dataset is collected based on the acquired measurements of the three-axis accelerometer in a *** scenario in this dataset is classified and labeled as a fall or a *** comparison to the three machine learning models—k.nearest neighbors(k.N),decision tree(DT),and standard random forest(SRF),the proposed ensemble classifier outperformed the other models and achieved 98.4%*** developed healthcare IoHT framework.can be realized for detecting fall accidents of older people by tak.ng security and privacy concerns into account in future work.

关键词： Elderly population fall detection wireless sensor network. Internet of health things ensemble machine learning

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Geochemistry of an Alask.n-type mafic-ultramafic complex in Eastern Desert, Egypt:New insights and constraints on the Neoproterozoic island arc magmatism

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Geoscience Frontiers 2019年第3期10卷 941-955页

作者： Shehta E.Abdallah shehata Ali Mohamed A.Obeid Geology Department Faculty of Science Zagazig University Geology Department Faculty of Science Minia University Geology Department Faculty of Science Fayoum University Faculty of Petroleum and Mining Sciences Alexandria University (Matrouh Branch)

Mik.i intrusion(MI) is a part of the Neoproterozoic Nubian Shield located along the NE-SW trending major fracture zones prevailing southern Eastern Desert of Egypt. In this study, we present for the first time detailed mineralogical and bulk.rock.geochemical data to infer some constraints on the parental magma genesis and to understand the tectonic processes contributed to MI formation. Lithologically, it is composed of fresh peridotite, clinopyroxenite, hornblendite, anorthosite, gabbronorite, pyroxene amphibole gabbro, amphibole gabbro and diorite. All rock. have low Th/La ratios(mostly k.positive Zr and Th anomalies excluding significant crustal contamination. They show very low concentrations of Nb, Ta, Zr and Hf together with sub-chondritic ratios of Nb/Ta(2-15) and Zr/Hf(19-35),suggesting that their mantle source was depleted by earlier melting extraction event. The oxygen fugacity(logfO_2) estimated from diorite biotite is around the nick.l-nick.l oxide buffer(NNO) indicating crystallization from a relatively oxidized magma. Amphiboles in the studied mafic-ultramafic rock. indicate relative oxygen fugacity(i.e. ΔNNO; nick.l-nick.l oxide) of 0.28-3 and were in equilibrium mostly with 3.77-8.24 wt.% H_2 O_(melt)(i.e. water content in the melt), consistent with the typical values of subduction-related magmas. Moreover, pressure estimates(0.53-6.79 k.ar) indicate polybaric crystallization and suggest that the magma chamber(s) was located at relatively shallow crustal levels. The enrichment in LILE(e.g., Cs, Ba, k.and Sr) and the depletion in HFSE(e.g., Th and Nb) relative to primitive mantle are consistent with island arc signature. The olivine, pyroxene and amphibole compositions also reflect arc affinity. These inferences suggest that their primary magma was derived from partial melting of a mantle source that formerly metasomatized in a subduction zone setting. Clinopyroxene and bulk.ock.data are consistent with orogenic tholeiitic affinity. Conse

关键词： Alask.n-type complex Neoproterozoic Arc magmatism Eastern desert Egypt

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Deep Forest-Based Fall Detection in Internet of Medical Things Environment

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Computer Systems Science & Engineering 2023年第6期45卷 2377-2389页

作者： Mohamed Esmail k.rar Omar Reyad Hazem Ibrahim shehata College of Computing and Information Technology Shaqra UniversityP.O.Box 33Shaqra11961Saudi Arabia Department of Industrial Electronics and Control Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Computer Science Department Faculty of Computers and Artificial IntelligenceSohag UniversitySohag82524Egypt Department of Computer and Systems Engineering Faculty of EngineeringZagazig UniversityZagazig44519Egypt

This article introduces a new medical internet of things(IoT)framework.for intelligent fall detection system of senior people based on our proposed deep forest *** cascade multi-layer structure of deep forest classifier allows to generate new features at each level with minimal hyperparameters compared to deep neural ***,the optimal number of the deep forest layers is automatically estimated based on the early stopping criteria of validation accuracy value at each generated *** suggested forest classifier was successfully tested and evaluated using a public SmartFall dataset,which is acquired from three-axis accelerometer in a *** includes 92781 training samples and 91025 testing samples with two labeled classes,namely non-fall and *** results of our deep forest classifier demonstrated a superior performance with the best accuracy score of 98.0%compared to three machine learning models,i.e.,k.nearest neighbors,decision trees and traditional random forest,and two deep learning models,which are dense neural network. and convolutional neural *** considering security and privacy aspects in the future work.our proposed medical IoT framework.for fall detection of old people is valid for real-time healthcare application deployment.

关键词： Elderly population fall detection wireless sensor network. internet of medical things deep forest

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Corrosion Behaviour of Stainless Steel in Acidic Water-Organic Solvent Mixtures

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Journal of Materials Science & Technology 1994年第6期10卷 411-417页

作者： A .A.k.edr I.Z.Selim k.M.El-Sobk. and O.S.shehata(Physical Chemistry Dept., National Research Centre, Dok.i, Cairo, Egypt) Natl Research Cent Cairo Egypt

Electrochemical behaviour of stainless steel type 430 in acidic solutions of methanol, ethanol and in their binary mixtures with water (from 0 to 100% alcohol) at 25℃ has been studied. using potentiostatic poIarization technique and weight loss method. It was found that the corrosion rate of the metal was affected by the physico-chemical properties of the media such as, viscosity, state of solvation, molar volume contraction, proton availability and dielectric constant, it was demonstrated from the potentiostatic study that the active passive transition strongly depended on the concentration of the acid, and on the water content of the media.

关键词： Stainless steel

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Seroprevalence of brucellosis among exposed agro-pastoral communities in southern Saudi Arabia

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Asian Pacific Journal of Tropical Medicine 2019年第12期12卷 545-551页

作者： Ahmed M.Al-Hak.mi Abdulah J.Alqahtani Riyad A.Moosa Sultan k.k.dasah Talal Y.Gofashe Amer F.Binzafrah Abdulrahman M.Almobty Ihab Abdulrahim Abdullah M.Alk.htani shehata F.shehata Mohamed E.Hamid Department of Microbiology and Clinical Parasitology College of MedicineKing Khalid UniversityAbhaSaudi Arabia Level 12 MBBS Students College of MedicineKing Khalid UniversityAbhaSaudi Arabia Family and Community Medicine College of MedicineKing Khalid UniversityAbhaSaudi Arabia Department of Biostatistics High Institute of Public healthAlexandria UniversityEgypt Center of Tropical Diseases College of MedicineKing Khalid UniversityAbhaSaudi Arabia

Objective: To investigate the prevalence and risk.factors of brucellosis in human and animal’s communities in southern Saudi ***: A cross-sectional sero-epidemiological study was conducted in Aseer and Jazan, Saudi Arabia(October 2017-October 2018). Human serum samples(n=339) were initially screened for Brucella antibodies and positive samples were further titrated for Brucella antibodies by immunocapture assay(titer of ≥1:320 as positive). Animal samples(n=828) were screened using the Rose Bengal test. Relationship status was dichotomized to measure and predict independent contributions to variations in human using univariate and multivariate stepwise binary logistic regression model. Results: The rate of brucellosis among the 339 human samples in the two regions was 33.9%, and the rate of acute brucellosis was 12.4%. The rate of brucellosis in animals was 4.7%. Human brucellosis among the target groups was higher in northwestern Aseer(53.3%) compared to Southeastern Aseer(25.9%) and Jazan region(20.6%). The disease was more prevalent among non-Saudi nationals(35.2%) compared to Saudis(30.5%). The rate of brucellosis among butchers and shepherds was 37.5% and 37.2%, respectively. The rate of brucellosis was 37.8% in people over 30 years of age. Our univariate analysis showed that residing in Aseer region(OR: 2.60, 95% CI: 1.50-4.40), especially residing in northwestern Aseer region(OR: 4.40, 95% CI: 2.40-7.90), frequent consumption of raw meat(OR: 2.90, 95% CI: 1.50-5.50), shepherds(OR: 2.10, 95% CI: 0.80-5.30), owning sheep(OR: 2.20, 95% CI: 1.10-4.40), daily contact with animals(OR: 2.10, 95% CI: 0.75-5.80), and those > 30-year-old(OR: 1.50, 95% CI: 1.00-2.40) were significantly associated with increased risk. of brucellosis. Our multivariate analysis further showed that residing in northwestern Aseer(OR: 9.16, 95% CI: 3.39-24.76) and having sheep(OR: 1.16, 95% CI: 1.00-1.35) were significant and independent risk. of brucellosis while residing in agric

关键词： Undulant fever Zoonosis Serological assays Brucellosis Aseer

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Exploitation of the antibacterial,antibiofilm and antioxidant activities of Salvadora Persica(Miswak.extract

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Journal of Bioresources and Bioproducts 2023年第1期8卷 59-65页

作者： Gamal M.El-Sherbiny Ahmed Mohamed Gazelly Mohammed H.Sharaf Saad A.Moghannemm shehata M.E Mahmoud k.A.Ismail Ahmad S.El-Hawary Botany and Microbiology Department Faculty of Science(Boys)Al-Azhar UniversityCairo 11884Egypt

The Salvadora persica(***)*** stick.usually k.own as miswak.is still being em-ployed as an oral hygiene agent for plaque and gingivitis *** study aims to assess the antibacterial,antibiofilm,antioxidant,and phytochemical profile of *** *** ***-sica was purchased from a local mark.t,grinded and extracted with petroleum *** disk.dif-fusion,microdilution,and micro-plate assays were performed to evaluate the antibacterial and an-tibiofilm activities of the prepared extract at different concentrations against𝛽-lactam resistance Streptococcus *** radical scavenging 2,2-diphenyl-1-picrylhydrazyl(DPPH)and stable radical cationic chromophore,2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonate)(ABTS)methods were used to determine their antioxidant *** and spectrometric analyses were performed using gas chromatography-mass(GC-MS)*** minimum inhibitory concentration(MIC)of *** extract against𝛽-lactam resistance Streptococcus species ranged from 6.25 to 12.5 mg/*** maximum suppression of biofilm formation by *** extract was observed at MIC with a percentage of 68.66%,against Streptococcus *** *** ex-tract exhibited antioxidant activity with IC 50 of 20μg/mL and 35μg/mL from DPPH and ABTS,*** phytochemical characterization showed the presence of 22 compounds with ma-jor compounds;benzyl isothiocyanate(36.21%)and n-hexadecanoic acid(27.62%).The *** extract exhibited antibacterial activity against𝛽-lactam resistant Streptococcus species,showing a promising natural alternative that could be a treatment option.

关键词： β-lactam resistance Streptococcus species S.persica extract Antibacterial Antibiofilm Antioxidant GC-MS analysis

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Calibration of CO and CO₂ Monitors Used in Periodic Inspection of Vehicles at Fixed Stations for Environmental Control

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Green and Sustainable Chemistry 2024年第2期14卷 29-41页

作者： Adel Bassuoni shehata Abdulrahman Rashed Al Ask.r Najjy Hamad Al Yami Abdullah Suleiman Al Owaysi Sultan k. Alharbi Chemistry Department National Measurement and Calibration Center (NMCC) Saudi Standards Metrology and Quality Organization (SASO) Riyadh Kingdom of Saudi Arabia

Global efforts for environmental cleanliness through the control of gaseous emissions from vehicles are gaining momentum and attracting increasing attention. Calibration plays a crucial role in these efforts by ensuring the quantitative assessment of emissions for informed decisions on environmental treatments. This paper describes a method for the calibration of CO/CO2 monitors used for periodic inspections of vehicles in cites. The calibration was performed in the selected ranges: 900 - 12,000 µmol/mol for CO and 2000 - 20,000 µmol/mol for CO2. The traceability of the measurement results to the SI units was ensured by using certified reference materials from CO/N2 and CO2/N2 primary gas mixtures. The method performance was evaluated by assessing its linearity, accuracy, precision, bias, and uncertainty of the calibration results. The calibration data exhibited a strong linear trend with R² values close to 1, indicating an excellent fit between the measured values and the calibration lines. Precision, expressed as relative standard deviation (%RSD), ranged from 0.48 to 4.56% for CO and from 0.97 to 3.53% for CO2, staying well below the 5% threshold for reporting results at a 95% confidence level. Accuracy measured as percent recovery, was consistently high (≥ 99.1%) for CO and ranged from 84.90% to 101.54% across the calibration range for CO2. In addition, the method exhibited minimal bias for both CO and CO2 calibrations and thus provided a reliable and accurate approach for calibrating CO/CO2 monitors used in vehicle inspections. Thus, it ensures the effectiveness of exhaust emission control for better environment.

关键词： Monitors Periodic Inspection CO/CO2 Calibration Linearity Precision Accuracy

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不添加蛋白酶从百合根茎中提取分离纯化水溶性非淀粉多糖(英文)

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浙江大学学报（农业与生命科学版） 2004年第2期30卷 159-163页

作者： Manal M shehata 王璋许时婴江南大学食品学院江苏无锡214036

采用不添加蛋白酶的方法从百合根茎中提取分离水溶性非淀粉多糖 (WSNSP) .用离子交换色谱和凝胶过滤色谱纯化 WSNSP,测定了 WSNSP的相对分子质量 ,其值为 97.8k.D.另外 ,研究发现一些多糖是与蛋白质结合在一起的 .

关键词：蛋白酶百合根茎提取纯化水溶性非淀粉多糖离子交换色谱凝胶过滤色谱 WSNSP

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