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New Trends in Fuzzy Modeling Through Numerical Techniques

Computers, Materials & Continua 2023年第3期74卷 6371-6388页

作者： M.M.Alqarni Muhammad Rafiq Fazal Dayan Jan Awrejcewicz Nauman ahmed Ali Raza Muhammad Ozair Ahmad Witold Pawłowski emad E.Mahmoud Department of Mathematics College of SciencesKing Khalid UniversityAbha61413Saudi Arabia Department of Mathematics Faculty of Sciences and TechnologyUniversity of Central PunjabLahorePakistan Department of Mathematics School of ScienceUniversity of Management and TechnologyLahorePakistan Department of Automation Biomechanics and MechatronicsLodz University of Technology1/15 Stefanowskiego St.90-924LodzPoland Department of Mathematics and Statistics University of LahoreLahorePakistan Department of Mathematics Govt.Maulana Zafar Ali Khan Graduate College WazirabadPunjab Higher Education Department(PHED)Lahore54000Pakistan Institute of Machine Tools and Production Engineering Lodz University of TechnologyPoland Department of Mathematics College of ScienceTaif UniversityP.O.Box11099Taif21944Saudi Arabia

Amoebiasis is a parasitic intestinal infection caused by the highly pathogenic amoeba Entamoeba *** is spread through person-toperson contact or by eating or drinking food or water contaminated with *** transmission rate depends on the number of cysts present in the *** traditional models assumed a homogeneous and contradictory transmission with *** heterogeneity of its transmission rate is a significant factor when modeling disease *** heterogeneity of disease transmission can be described mathematically by introducing fuzzy *** this context,a fuzzy SEIR Amoebiasis disease model is considered in this *** equilibrium analysis and reproductive number are studied with *** numerical schemes forward Euler method and a nonstandard finite difference(NSFD)approach,are developed for the learned model,and the results of numerical simulations are *** numerical and simulation results reveal that the proposed NSFD method provides an adequate representation of the dynamics of the disease despite the uncertainty and ***,the obtained method generates plausible predictions that regulators can use to support decision-making to design and develop control strategies.

关键词： Epidemic model fuzzy parameters amoebiasis NSFD scheme convergence

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Enhancing the Performance of the Marine and Tidal Current Converters Using DC-DC Boost Converter

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Journal of Energy and Power Engineering 2012年第3期6卷 478-484页

作者： emad M. ahmed Masahito Shoyama Graduate School of Information Science and Electrical Engineering Kyushu University Fukuoka 812-0395 Japan

Due to the highly demand on the renewable energy sources as a free and a clean power resource, extracting energy from unsteady flow using marine and tidal current turbines has a distinct focusing nowadays. For their resource characteristic, extracting energy from marine/tidal current needs a simple and robust converter, which could overcome the drawbacks of the mechanical system such as gearbox and enhance conversion system stability. In this paper a new AC-DC-AC conversion system has been proposed. The new conversion system contains a middle stage DC-DC boost converter, which boost the generated rectified DC voltage higher enough that can enable the PWM inverter to generate the required voltage with the synchronized frequency. In order to investigate the efficient performance of the proposed conversion system especially at low current speed compared to the conventional one, different operating conditions have been studied. Moreover, the effect of including boost converter on the THD （total harmonic distortion） has also been checked. The new conversion system presents its capability to enhance and improve system performance not only with low current speed but also with high current speed.

关键词： Renewable energy marine and tidal current energy AC-DC-AC converter DC-DC boost converter.

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Impedance spectroscopy and DFT/TD-DFT studies of diyttrium trioxide for optoelectronic fields

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Journal of Rare Earths 2023年第4期41卷 605-612页

作者： Ali A.Alkathiri A.A.Atta Moamen S.Refat Sonam Shakya A.M.Hassanien Saud A.Algarni emad M.A.ahmed Sultan E.Alomariy Mohammed Alsawat Norah Algethami Department of Physics College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Chemistry Aligarh Muslim UniversityAligarh202002India Department of Physics Faculty of Science and Humanity Studies at Al-QuwayiyahShaqra UniversityAl-Quwayiyah11971Saudi Arabia

Yttrium(Ⅲ)oxide or so-called diyttrium trioxide(Y_2O_3)is an excellent candidate ceramic material for optoelectronic ***,electrical conductivity,and dielectric relaxation properties of bulk yttrium(Ⅲ)oxide were studied.X-ray diffraction(XRD)results indicate that the yttrium(Ⅲ)oxide compound has a crystalline cubic *** transform infrared(FTIR)technique was used to ascertain the chemical structure of the yttrium(Ⅲ)oxide *** spectroscopy was used to analyze frequency-dependent electrical properties as a function of temperature in the range of 303-423 K and frequency range of 0.1 Hz-2 *** spectroscopy parameters such as dielectric constant,dielectric loss,loss factor,electric modulus,and complex impedance of the yttrium(Ⅲ)oxide compound were *** Nyquist plot describes the complex impedance of the yttrium(Ⅲ)oxide for different *** universal Jonscher's power law was used for the analysis of the complex electrical conductivity of the yttrium(Ⅲ)oxide *** is found that the real(σ')and imaginary(σ")parts of the complex conductivity increase with increasing *** exponent frequency(s)equals unity,which confirms that the predominant conduction mechanism is a nearly constant loss(NCL)***/TD-DFT studies using B3LYP/LanL2DZ level of theory were used to provide comparable theoretical data and electronic energy gap of HOMO→LUMO.

关键词： Yttrium(Ⅲ)oxidel Impedance spectroscopy DFT/TD-DFT Rare earths

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Structural, Magnetic and Dielectric Properties of Fe-Co Co-Doped Ba0.9Sr0.1TiO3Prepared by Sol Gel Technique

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New Journal of Glass and Ceramics 2014年第2期4卷 19-28页

作者： Inas Kamal Batttisha ibrahim Sayed ahmed Farag Mostafa Kamal Mohamed Ali ahmed emad Girgis Hesham Azmi El Meleegi Fawzi Gooda El Desouky Materials Science Lab (1) Physics Department Faculty of Science Cairo University Giza Egypt Metal Physics Laboratory Physics Department Faculty of Science Mansoura University Mansoura Egypt National Research Center (NRC) Solid State Physics Department Dokki Giza Egypt National Research Centre (NRC) Thin Film Lab Electron Microscope Department Dokki Giza Egypt

The structural, dielectric and magnetic properties of pure and Fe-Co co-doped Ba0.9Sr0.1TiO3, (Ba(1-x)SrxTiO3, where (x = 0.10) and (Ba0.9Sr0.1Ti(1-x-y)FexCoyO3), where (x = 0.1, y = 0) and (x = 0 and y = 0.10) and (x = 0.5, y = 0.5) in powder form, abbreviated as (BST) and (BST10FO), (BST10CO) and (BST5F5CO), respectively were prepared by a modified sol gel technique. Crystallization, surface morphology and electrical behavior of BST are improved by Fe3+ and Co2+ ions with optimized grain size. Phase identification by using X-ray diffraction and surface morphology will be studied by using transmission electron microscope (TEM) and scanning electron microscope imaging (SEM). Phase identification by using X-ray diffraction and surface morphology evaluation by using transmission electron microscope (TEM) and scanning electron microscope imaging (SEM) will be studied. The nano-scale presence and the formation of the tetragonal perovskite phase as well as the crystallinity were detected using the mentioned techniques. The dielectric properties of the prepared samples have been investigated as a function of temperature and frequency. The dielectric measurements are carried out in the frequency range of 42 Hz - 1 MHz, at temperature ranging between 25°C and 250°C. The results showed an abrupt decrease in the dielectric permittivity by increasing the frequency range. The magnetic hysteresis loop confirmed enhancement in the magnetization properties by co-doping with Fe3+-Co2+ ions. An increase in the saturation of the magnetization at room temperature was detected by decreasing the crystallite sizes of the prepared samples.

关键词： Sol Gel Nano-Structure Magnetic Hysteresis Loop Dielectric Permittivity Nano-Composite BaSrTiO3 (BST) TEM XRD SEM

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Melting and Corrosion Behavior of Al-9Zn Based Alloys with Cu and Mg Additions

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Materials Sciences and Applications 2011年第5期2卷 469-475页

作者： El Said Gouda emad ahmed Nabih Tawfik 不详

In the present paper, the effect of Mg and Cu additions on melting, mechanical and corrosion behavior of Al-9Zn alloy was studied and analyzed. It was found that, addition of Cu and Mg led to form the Al-Cu, Al-Mg and Mg-Zn intermetallic compounds. These compounds tend to increase the hardness values due to the precipitation strengthening hardening mechanism of these compounds. Also corrosion behavior of the Cu and Mg content alloys measured by the weight loss method is better than those of the Al-9Zn alloy. Furthermore, corrosion resistance of the Cu content alloys is superior to that of the Mg content alloys.

关键词： Corrosion Hardness Melting Point Aerospace Alloys

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Dielectric and Magnetic Properties of Nano-Structure BiFeO3Doped with Different Concentrations of Co Ions Prepared by Sol-Gel Method

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New Journal of Glass and Ceramics 2015年第3期5卷 59-73页

作者： Inas Kamal Batttisha ibrahim Sayed ahmed Farag Mostafa Kamal Mohamed Ali ahmed emad Girgis Fawzi El Desouki Hesham Azmi El Meleegi Fawzi El Desouki National Research Centre (NRC) Solid State Physics Department 33 Bohouth St Dokki Giza Egypt Metal Physics Laboratory Physics Department Faculty of Science Mansoura University Mansoura Egypt Materials Science Lab (1) Physics Department Faculty of Science Cairo University Giza Egypt National Research Centre (NRC) Thin Film Lab Electron Microscope Department 33 Bohouth St Dokki Giza Egypt

BiFe1-xCoxO3 (x = 0, 0.03, 0.05 and 0.1) symbolic as (BFO, BF3CO, BF5CO and BF10CO) in powder form has been prepared by sol-gel technique using ethylenediamine tetraacetic acid (EDTA) as a chelating agent. X-ray diffraction (XRD) and FTIR analysis showed rhombohedra distorted BiFeO3 structure with compressive lattice distortion induced by the Co substitution at Fe sites. The transmission electron microscope (TEM) shows irregular particles. The additive of cobalt oxide has led to grains refining giving the following crystallite sizes of 18 nm for BF5Co. The scanning electron microscope (SEM) study reveals that the samples morphology shows relatively uniform grain size distribution. The dielectric properties of BiFeO3 nano-particles in the frequency range of 1 up to 5 MHz at RT revealed that the A.C. conductivity of the prepared samples reaches its maximum value in BF5CO. By decreasing BiFeO3 particle size as a result of doping with different Co ion concentrations, an enhancement in magnetization and a simultaneous suppression in current leakage occurred. The remnant magnetization Mr of BiFe1-xCoxO3 (x = 0, 0.03, 0.05, 0.1) ceramics significantly enhanced, which provides potential applications in information storage.

关键词： Nano-Structure Multiferroic BiFe1-xCoxO3 (x = 0 0.03 0.05 0.1) XRD FTIR TEM Remnant Magnetization

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新型液相色谱-荧光检测法测定药物剂型和人血浆中的他达拉非和盐酸达泊西汀(英文)

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色谱 2015年第7期33卷 765-770页

作者： MAHA Hegazy AMIRA Kessiba MOHAMED Abdelkawy ahmed emad El Gindy Analytical Chemistry Department Faculty of PharmacyCairo University Pharmaceutical Chemistry Department Faculty of PharmacyMisr International University Pharmaceutical Chemistry Department Faculty of PharmacyFuture University

Tadalafil(TAD)and dapoxetine HCl(DAP)are recently co-formulated and both show native ***,a novel,accurate,specific and sensitive reversed-phase high performance liquid chromatographic method with fluorescence detection was developed and validated for their separation and quantitation in dosage form and human plasma using avanafil as an internal standard(IS).Separation was achieved using isocratic elution within 7.0 min on C18column and acetonitrile-0.15%triethylamine(40∶60,v/v;pH 4)as a mobile *** flow rate was 1.0 mL/min and the detection was time-programmed at 330,410 and 370 nm for TAD,DAP and IS,respectively,after excitation at 236 *** linear ranges from 0.01 to 30.00μg/mL for each drug with the limits of detection of 4.20 and 7.20 ng/mL for TAD and DAP,*** method was validated in accordance to the International Conference on Harmonization(ICH)guidelines and was successfully applied to spiked human plasma with mean recoveries of 98.17%and 98.83%for TAD and DAP respectively.

关键词： high performance liquid chromatography(HPLC) fluorescence detection tadalafil(TAD) dapoxetine HCl(DAP) dosage form human plasma

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基于CFD的海底管道石油泄漏规律研究

基于CFD的海底管道石油泄漏规律研究

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作者： emad ahmed ABDULGHAFFAR HASSAN（海桑）西安石油大学

学位级别：硕士

石油泄漏是一个严重的问题,一旦发生油气泄漏,将对自然生态系统和海洋环境造成极大的威胁和破坏。为了更好地支持也门共和国东南海岸阿拉伯海海底石油泄漏的风险评估和污染控制,本文建立了也门共和国东南海岸阿拉伯海海底局部输油管道... 详细信息

石油泄漏是一个严重的问题,一旦发生油气泄漏,将对自然生态系统和海洋环境造成极大的威胁和破坏。为了更好地支持也门共和国东南海岸阿拉伯海海底石油泄漏的风险评估和污染控制,本文建立了也门共和国东南海岸阿拉伯海海底局部输油管道二维瞬态数值模型,并将海底石油泄漏分为海底裸露输油管道泄漏和海底埋地输油管道泄漏两种情况,研究了海水流速、泄漏速度、泄漏口角度、海底输油管道埋地深度、海泥孔隙率和原油密度对海泥和水体中石油泄漏扩散特征和运移规律的影响。得到了两种情况下漏油在海水中的横向扩散速度与原油密度之间的关系式,研究结果可为海底输油管道的泄漏事故处理工作提供有效的指导和一定的理论依据。研究了海底裸露管道泄漏扩散特性,结果表明石油泄漏后在水中形成了一股射流,油品扩散到达海面的时间随海水流速的增大而增大,当海水流速从0.1 m/s增大到0.5 m/s时,溢油扩散到达海面的时间从14 s增大到34 s。随海底输油管道泄漏口径的增大而减小,当海底输油管道泄漏口径从30 mm增大到70 mm时,溢油扩散到达海面的时间从19 s缩短到了12 s。随泄漏速度的增大而减小,当泄漏速度从2 m/s增大到8 m/s时,溢油扩散到达海面的时间从23 s缩短到了9 s。泄漏口方向在管道顶部的下游时,随着海底输油管道泄漏口朝向与竖直方向的夹角的增大,原油泄漏后的水平扩散距离和垂直扩散距离均先增大后减小。溢油扩散到达海面的时间先减小后增大,当海底输油管道泄漏口朝向与竖直方向的夹角为60°时,原油能更快扩散到达海面。泄漏口方向在管道顶部的上游时,随着泄漏口角度的增大,溢油扩散到达海面的时间增大。当海底输油管道泄漏口朝向与竖直方向的夹角为30°时,泄漏的原油几乎垂直向上运动,在较短的时间内便能扩散到达海面。研究了海底埋地管道泄漏扩散特性,结果表明泄漏油品在海泥中呈圆形扩散形态。海水流速主要影响油品在水体中的扩散特性,而对海泥区域的油品扩散规律影响较小。泄漏油品到达海泥-海水交界面的时间随泄漏速度的增大而减小,当泄漏速度从2 m/s增大到8 m/s时,泄漏油品扩散到海泥-海水交界面的时间从10 s减小到5 s。海泥-海水交界面被油品所覆盖的宽度范围约为3～5 m,并随着海底输油管道埋地深度的增加和泄漏时间的延长而加宽,泄漏油品到达海面的时间随着海底输油管道埋地深度的增加而增大,当海底输油管道埋地深度从0.5 m增加到1.5 m时,泄漏油品到达海面的时间从20 s增大到30 s。海泥中的渗透速度随着海泥孔隙率的增大而减小,研究结果表明考虑周围的海泥环境有助于合理判断石油泄漏的污染范围。对比分析了两种情况下不同密度的原油发生泄漏后的扩散特性,结果表明油品密度越小,受海水浮力的作用越大,随着海水流动向水平方向扩散的速度越大。与海底裸露管道相比,海底埋地管道发生泄漏后,油品扩散速度较小。此外,进一步拟合得到了海底裸露管道和海底埋地管道两种情况下,漏油在海水中的横向扩散速度与原油密度之间的关系式,从而可以为制定不同情况下的海上漏油应急预案提供指导。

关键词：石油泄漏扩散海泥孔隙率泄漏角度流体模拟

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Sizing and Design of the PV-WIND Energy Dryer for Medical Herbs

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Smart Grid and Renewable Energy 2013年第2期4卷 217-226页

作者： emad ahmed Sweelem Abdel-Shafy A. Nafeh Faten Hosny Fahmy PV Cells Department Electronics Research Institute Cairo Egypt

Medical herbs are located in Egypt in different areas and they are very important to increase the national income of Egypt. It is necessary to dry the herbs in their growing locations. As the growing locations are located far from the natural supply grid of Egypt, renewable energy sources such as PV&WIND are preferably utilized to achieve the drying process. Moreover, since the drying process is actually used to remove water from the herbs, thus it can preserve the herbs in storage drastically by preventing the attack of microorganisms during the moist conditions of herbs and also reduce their weight and bulk (for cheaper transport). Where, this paper selects, at first, the suitable drying site, and then it suggests. The suggested drying system is completely designed, and includes the following three systems: the solar thermal system, the dryer, and the renewable energy system.

关键词： Medical Herbs Dryer Solar Thermal System Renewable Energy

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The Effect of Gold Salt Concentration in the Production of Gold Nanospheres

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Journal of Applied Mathematics and Physics 2020年第8期8卷 148-1495页

作者： Sabreen Juda Badi emad K. Al-Shakarchi Shyma’a Jamal ahmed Physics Department College of Science Al-Nahrain University Baghdad Iraq College of Medicine University of Baghdad Baghdad Iraq

The optical, electrical and chemical properties of the gold nanospheres synthesized by different gold concentrations in deionized water through a simple chemical reduction method (Turkevich method) were studied. They were dependent on the variation of the gold salt concentration. The peaks of the surface Plasmon resonance (SPR) absorption band and their wavelengths were detected by a UV-visible spectrophotometer. The diameters of the spherical gold nanoparticles were measured theoretically using UV-visible absorption spectrum analysis of the synthesized gold nanoparticles in colloidal form by calculating the ratio of the absorbance at the surface Plasmon resonance (SPR) peak to the absorbance at the lowest peak closed to SPR peak. The values of the gold nanoparticles diameters were (23 nm) and decreased to (13 nm) as the function of molarity changed in the range (0.1 - 0.3 mM). They were compared with the results of the transmission electron microscopy (TEM), which was about (15 - 20 nm) measured by the reference images of Sigma-Aldrich values. The conductivity measurements showed increasing the conductivity with molarity increased. The total dissolved solids (TDS) exhibited increase by linear relation with molarity increasing. The pH-value of the gold nanoparticles solutions varied with the molarity and recorded a bowing value of pH-value at (0.2 mM).

关键词： Gold Nanoparticles Turkevich Method Surface Plasmon Resonance Total Dissolved Solids Conductivity Measurements

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