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Strength and Wear Behavior of mg Alloy AE42 Reinforced with Carbon Short Fibers

Acta metallurgica Sinica(English Letters) 2019年第1期32卷 31-40页

作者： Sabbah Ataya Naser A.Alsaleh mohamed m.el-Sayed Seleman metallurgical and materials Engineering Department Faculty of Petroleum and Mining Engineering Suez University Department of mechanical Engineering College of Engineering Al Imam Mohammad Ibn Saud University

In addition to the advantage of the lightweight of magnesium alloys, magnesium composites have moderate strength and elastic modulus. The proposed application of magnesium composites as diesel truck pistons makes it necessary to assess their wear performance. Little research data have been discussed on wear behavior of mg alloy AE42 matrix and its composites. Thus, this paper reports wear behavior of magnesium alloy AE42(mg–Al–mn—RE; rare earth) and its composite AE42-C, which contains 23 vol% of randomly oriented carbon short fibers. materials characterization, including density measurements, hardness testing, microstructures investigation, and compression testing at temperatures of 25, 150,and 300 °C, were conducted. Wear tests were performed under various loads and sliding distances. Wear mechanisms were also proposed based on the examination of worn surfaces using optical microscopy and scanning electron microscopy equipped with EDX(energy-dispersive X-ray spectrometry) analysis system. The hardness of AE42-23 vol% C composite is twice the hardness of the mg matrix alloy AE42. Significant improvements to yield stress and compressive strength at temperatures of 25, 150, and 300 °C of the composite versus the AE42 alloy are achieved. Wear resistance of the composite is improved considerably versus that of the mg alloy AE42 at the various sliding distances. Smearing of graphite on the worn surface produces a lubricating film that delays change from mild to severe wear of the composite, especially at high loads. EDX analysis of the worn surface shows oxidation of the matrix alloy at higher wear loads, and this mechanism decreases in the presence of carbon fibers under the same loads. Abrasive wear, oxidation, and plastic deformation are the dominant wear mechanisms for the alloy matrix AE42, whereas mainly abrasive wear is the wear mechanism of AE42-23 vol% C composite under the proposed testing conditions.

关键词： magnesium composites Carbon short fibers Compressive strength Wear resistance Wear mechanisms

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ellipsometric configurations using a phase retarder and a rotating polarizer and analyzer at any speed ratio

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Chinese Physics B 2012年第11期21卷 154-166页

作者： Sofyan A.Taya Taher m.el-Agez Anas A.Alkanoo Physics Department Islamic University of Gaza

In this paper, we propose an ellipsometer using a phase retarder and rotating polarizer and analyzer at a speed ratio I：N. Different ellipsometric configurations are presented by assuming N = 1, 2, and 3. moreover, two values of the offset angle of the retarder are considered for each ellipsometric configuration. The m.eller formalism is employed to extract the Stokes parameters, from which the intensity received by the detector is obtained. The optical properties of c-Si are calculated using all configurations. A comparison between different configurations is carried out considering the effect of the noise on the results and the uncertainties in the ellipsometric parameters as functions of the uncertainties of the Fourier coefficients. It is found that the alignment of the phase retarder has a crucial impact on the results and the ellipsometric configuration with speed ratio 1：1 is preferred over the other configurations.

关键词： ellipsometry phase retarder rotating polarizer and analyzer

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Solitary wave solutions for the variable-coefficient coupled nonlinear Schrödinger equations and Davey-Stewartson system using modified sine-Gordon equation method

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Journal of Ocean Engineering and Science 2020年第2期5卷 180-185页

作者： Rehab m.el-Shiekh mahmoud Gaballah Department of mathematics College of Science and Humanities at Howtat SudairMajmaah University11952Saudi Arabia Department of Physics College of Science at Al-ZulfiMajmaah University11952Saudi Arabia Department of mathematics Faculty of EducationAin Shams UniversityCairoEgypt

In this study,the sine-Gordon equation method is modified to deal with variable-coefficient systems containing imaginary parts,such as nonlinear Schrödinger *** are of considerable importance in many fields of research,including ocean engineering and *** an example,we apply the modified method to variable-coefficient coupled nonlinear Schrödinger equations and Davey-Stewartson system with variable coefficients,treating them as one-dimensional and two-dimensional systems,*** a result of this application,novel solitary wave solutions are obtained for both ***,some figures are provided to illustrate how the solitary wave propagation is determined by the different values of the variable group velocity dispersion terms,which can be used to model various phenomena.

关键词： Coupled nonlinear Schrödinger equations Davey-Stewartson system with variable coefficients Sine-Gordon equation method Solitary waves

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On Soft Pre-Rough Approximation Space with Applications in Decision making

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Computer modeling in Engineering & Sciences 2022年第9期132卷 865-879页

作者： m.el Sayed Wadia Faid Hassan Al-shameri m.A.el Safty Department of mathematics College of Science and ArtsNajran UniversityNajran66445Saudi Arabia Department of mathematics and Statistics College of ScienceTaif UniversityTaif21944Saudi Arabia

A soft,rough set model is a distinctive mathematical model that can be used to relate a variety of real-life *** the present work,we introduce new concepts of rough set based on soft pre-lower and soft pre-upper approximation *** concepts are soft pre-rough equality,soft pre-rough inclusion,soft pre-rough belonging,soft predefinability,soft pre-internal lower,and soft pre-external *** study the properties of these ***,we use the soft pre-rough approximation to illustrate the importance of our method in decision-making for Chikungunya medical *** reality,the impact factors of Chikungunya’s medical infection were ***,we develop two new algorithms to address Chikungunya virus *** proposed approach is sensible and effective.

关键词： Soft rough set soft pre-rough set approach soft pre-internal lower and soft pre-external upper soft nowhere dense set and Chikungunya medical application intelligence discovery

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Alumina Effect on the Phase Transformation of 3Y-TZP Ceramics

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Journal of materials Science & Technology 2008年第6期24卷 873-877页

作者： Ezzat S.elshazly m.el-Sayed Ali S.m.el-Hout Department of metallurgy Nuclear Research CenterAtomic Energy AuthorityCairoEgypt

The isothermal tetragonal-to-monoclinic phase transformation of 3 mol fraction Y2O3-ZrO2 ceramics contain- ing different amounts of Al2O3 during ageing in water at 130℃ for periods of time up to 40 h was investigated to explore the effect of Al2O3 addition on this transformation. The propagation of the transformation into the specimen interiors was suppressed by the addition of Al2O3. The transformation kinetics showed a nucleation and growth mechanism on the specimen surface to be dominant in the low temperature ageing in water environment.

关键词： Phase transformation 3Y-TZP Al2O3 Kinetics

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microstructure and mechanical properties of hot extruded 6016 aluminum alloy/graphite composites

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Journal of materials Science & Technology 2018年第9期34卷 1580-1591页

作者： mohamed m.el-Sayed Seleman mohamed m.Z.Ahmed Sabbah Ataya Department of metallurgical and materials Engineering Faculty of Petroleum and Mining Engineering Suez University 43518 Suez Egypt Suez and Sinai metallurgical and materials Research Center of Scientific Excellence (SSmmR-CSE) 43518 Suez Egypt The British University in Egypt Mechanical Engineering Deportment El-Sherouk City 11837 Cairo Egypt Department of mechanical Engineering College of Engineering AI Imam Mohammad Ibn Saud Islamic University Riyadh 11432 saudi Arabia

The incorporation of graphite particles into AA6016 aluminum alloy matrix to fabricate metal/ceramic composites is still a great challenge and various parameters should be considered. In this study, dense AA6016 aluminum alloy/（0-20 wt%） graphite composites have successfully been fabricated by powder metallurgy process. At first, the mixed aluminum and graphite powders were cold compacted at 200 mPa and then sintered at 500 ℃ for 1 h followed by hot extrusion at 450 ℃. The influence of ceramic phases（free graphite and in-situ formed carbides） on microstructure, physical and mechanical properties of the produced composites were finally investigated. The results show that the fabricated composites have a relative density of over 98%. SEm observations indicate that the graphite has a good dispersion in the alloy matrix even at high graphite content. Hardness of all the produced composites was higher than that of aluminum alloy matrix. No cracks were observed at strain less than 23% for all hot extruded *** strength, reduction in height, ultimate tensile stress, fracture stress, yield stress, and fracture strain of all Al/graphite composites were determined by high precision second order equations. Both compressive and ultimate tensile strengths have been correlated to microstructure constituents with focusing on the in-situ formed ceramic phases, silicon carbide（SiC） and aluminum carbide（Al4 C3）. The ductile fracture mode of the produced composites became less dominant with increasing free graphite content and in-situ formed carbides. Wear resistance of Al/graphite composites was increased with increasing graphite content. Aluminum/20 wt% graphite composite exhibited superior wear resistance over that of AA6016 aluminum alloy.

关键词： AA6016/graphite composites Hot extrusion In-situ carbides mechanical properties Wear resistance Fracture behavior

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Using BlazePose on Spatial Temporal Graph Convolutional Networks for Action Recognition

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Computers, materials & Continua 2023年第1期74卷 19-36页

作者： motasem S.Alsawadi el-Sayed m.el-kenawy miguel Rio electronic and electrical Engineering Department University College LondonLondonWC1E 7JEEngland Department of Communications and electronics Delta Higher Institute of Engineering and TechnologyMansoura35111Egypt Faculty of Artificial Intelligence Delta University for Science and TechnologyMansoura35712Egypt

The ever-growing available visual data(i.e.,uploaded videos and pictures by internet users)has attracted the research community’s attention in the computer vision ***,finding efficient solutions to extract knowledge from these sources is ***,the BlazePose system has been released for skeleton extraction from images oriented to mobile *** this skeleton graph representation in place,a Spatial-Temporal Graph Convolutional Network can be implemented to predict the *** hypothesize that just by changing the skeleton input data for a different set of joints that offers more information about the action of interest,it is possible to increase the performance of the Spatial-Temporal Graph Convolutional Network for HAR ***,in this study,we present the first implementation of the BlazePose skeleton topology upon this architecture for action ***,we propose the Enhanced-BlazePose topology that can achieve better results than its ***,we propose different skeleton detection thresholds that can improve the accuracy performance even *** reached a top-1 accuracy performance of 40.1%on the Kinetics *** the NTU-RGB+D dataset,we achieved 87.59%and 92.1%accuracy for Cross-Subject and Cross-View evaluation criteria,respectively.

关键词： Action recognition BlazePose graph neural network OpenPose skeleton spatial temporal graph convolution network

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Forecasting E-Commerce Adoption Based on Bidirectional Recurrent Neural Networks

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Computers, materials & Continua 2022年第3期70卷 5091-5106页

作者： Abdullah Ali Salamai Ather Abdulrahman Ageeli el-Sayed m.el-kenawy Community college Jazan UniversityJazanKingdom of Saudi Arabia Department of Communications and electronics Delta Higher Institute of Engineering and TechnologyMansoura35111Egypt

E-commerce refers to a system that allows individuals to purchase and sell things *** primary goal of e-commerce is to offer customers the convenience of not going to a physical store to make a *** will purchase the item online and have it delivered to their home within a few *** goal of this research was to develop machine learning algorithms that might predict e-commerce platformsales.A case study has been designed in this paper based on a proposed continuous Stochastic Fractal Search(SFS)based on a Guided Whale Optimization Algorithm(WOA)to optimize the parameter weights of the Bidirectional Recurrent Neural Networks(BRNN).Furthermore,a time series dataset is tested in the experiments of e-commerce demand ***,the results were compared to many versions of the state-of-the-art optimization techniques such as the Particle Swarm Optimization(PSO),Whale Optimization Algorithm(WOA),and Genetic Algorithm(GA).A statistical analysis has proven that the proposed algorithm can work significantly better by statistical analysis test at the P-value less than 0.05 with a one-way analysis of variance(ANOVA)test applied to confirm the performance of the proposed ensemble *** proposed Algorithm achieved a root mean square error of RmSE(0.0000359),mean(0.00003593)and Standard Deviation(0.000002162).

关键词： Neural networks e-commerce forecasting risk management machine learning

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Softζ-Rough Set and Its Applications in Decision making of Coronavirus

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Computers, materials & Continua 2022年第1期70卷 267-285页

作者： m.A.el Safty Samirah Al Zahrani m.K.el-Bably m.el Sayed Department of mathematics and Statistics College of ScienceTaif UniversityTaif21944Saudi Arabia Department of mathematics Faculty of ScienceTanta UniversityTantaEgypt Department of mathematics College of Science and ArtsNajran UniversityNajran66445Saudi Arabia

In this paper,we present a proposed method for generating a soft rough approximation as a modification and generalization of Zhaowen et *** were obtained between our approach and the previous study and ***,an application on Coronavirus(COVID-19)has been presented,illustrated using our proposed concept,and some influencing results for symptoms of Coronavirus patients have been ***,following these concepts,we construct an algorithm and apply it to a decision-making problem to demonstrate the applicability of our proposed ***,a proposed approach that competes with others has been obtained,as well as realistic results for patients with ***,we used mATLAB programming to obtain the results;these results are consistent with those of theWorld Health Organization and an accurate proposal competing with the method of Zhaowen et *** been ***,it is recommended that our proposed concept be used in future decision making.

关键词： Soft set soft rough set softζrough set COVID-19 intelligence discovery decision making

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In vitro digestibility of Aucklandia costus-loaded nanophytosomes and their use in yoghurt as a food model

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Food Bioscience 2022年第6期50卷 1016-1024页

作者： Fadwa W.Abdulqahar Tamer m.el-messery Ahmed A.Zaky marwa m.el-Said Food Science Department College of AgricultureUniversity of AnbarRamadyIraq Dairy Department Food Industries and Nutrition Research InstituteNational Research CentreDokkiCairo12622Egypt Department of Food Technology Food Industries and Nutrition Research InstituteNational Research CentreDokkiCairo12622Egypt

This work achieved the encapsulation of valuable bioactive substances from Aucklandia costus(AC)in nanophytosomes as a new phytoconstituent delivery *** fluid extraction(SFE)and solvent-maceration methods were used to extract oil and phenolics from AC,*** physicochemical characterization of SFE-oil and phenolic extract(PE)-High-performance liquid chromatography(HPLC)and Gas chromatography–mass spectrometry(GC-mS)were used to identify and quantify all compounds extracted from AC using both extraction *** nanophytosomes was studied using dynamic light scattering(DLS),encapsulation efficiency(EE),and transmission electron microscopy(TEm).The in vitro digestibility of SFE-oil and PE-loaded nanophytosomes after in vitro digestion was *** was selected as a food model for fortification with AC-loaded nanophytosomes at different concentrations(5%,10%,and 15%).pH,acidity,water holding capacity(WHC),and viscosity were evaluated in all yoghurt samples during storage,while color analysis and sensory evaluation were evaluated at 0 *** SFE-oil-and PE-loaded nanophytosomes showed promising results,and the bioavailability suggested that nanoencapsulation provided a controlled release of the phenolic and flavonoid ***,the addition of AC-loaded nanophytosomes into yoghurt resulted in increases in the viscosity(16.53 Pa s-1)and decreases in WHC(59.50%).Yoghurts with AC-loaded nanophytosomes were more stable than the control(yoghurt without nanophytosomes).Overall,the current findings indicated that AC-loaded nanophytosomes would be a preferable candidate for incorporation into yoghurt to improve its *** research might provide scientific evidence supporting AC-loaded nanophytosomes as possible fortifying elements in manufacturing functional yoghurt and a new vision for designing unique dairy products with functional qualities.

关键词： Aucklandia costus Supercritical fluid extraction maceration Nanophytosomes Yoghurt

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