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Magneto-Photo-Thermoelastic Excitation Rotating Semiconductor Medium Based on Moisture Diffusivity

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 107-126页

作者： Khaled Lotfy A.M.S.mahdy Alaa A.El-Bary E.S.Elidy Department of Mathematics Faculty of ScienceZagazig UniversityZagazig44519Egypt Department of Mathematics Faculty of ScienceTaibah UniversityMadinah42353Saudi Arabia Department of Mathematics and Statistics College of ScienceTaif UniversityTaif11099Saudi Arabia Arab Academy for Science Technology and Maritime TransportAlexandria1029Egypt

In this research,we focus on the free-surface deformation of a one-dimensional elastic semiconductor medium as a function of magnetic field and moisture *** problem aims to analyze the interconnection between plasma and moisture diffusivity processes,as well as thermo-elastic *** study examines the photothermoelasticity transport process while considering the impact of moisture *** employing Laplace’s transformation technique,we derive the governing equations of the photo-thermo-elastic *** equations include the equations for carrier density,elastic waves,moisture transport,heat conduction,and constitutive *** stresses,thermal conditions,and plasma boundary conditions are used to calculate the fundamental physical parameters in the Laplace *** employing numerical techniques,the Laplace transform is inverted to get complete time-domain solutions for the primary physical domains under ***,thermoelastic,and thermoelectric characteristics are employed in conjunction with a g.a.hical analysis that takes into consideration the effects of applied forces on displacement,moisture concentration,carrier density,stress due to forces,and temperature distribution.

关键词： Moisture diffusivity semiconductor photothermoelastic rotation thermomechanical waves laplace transform

High-Order Spatial FDTD Solver of Maxwell’s Equations for Terahertz Radiation Production

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Journal of Applied Mathematics and Physics 2024年第4期12卷 1028-1042页

作者： Abdelrahman mahdy Department of Physical Sciences College of Science Jazan University Jazan Kingdom of Saudi Arabia

We applied a spatial high-order finite-difference-time-domain (HO-FDTD) scheme to solve 2D Maxwell’s equations in order to develop a fluid model employed to study the production of terahertz radiation by the filamentation of two femtosecond lasers in air plasma. We examined the performance of the applied scheme, in this context, we implemented the developed model to study selected phenomena in terahertz radiation production, such as the excitation energy and conversion efficiency of the produced THz radiation, in addition to the influence of the pulse chirping on properties of the produced radiation. The obtained numerical results have clarified that the applied HO-FDTD scheme is precisely accurate to solve Maxwell’s equations and sufficiently valid to study the production of terahertz radiation by the filamentation of two femtosecond lasers in air plasma.

关键词： The Finite-Difference-Time-Domain Terahertz Radiation Production Filamentation of Femtosecond Laser Maxwell’s Equations Solution

Advancing Early Detection of Colorectal Adenomatous Polyps via genetic Data Analysis: A Hybrid Machine Learning.a.proach

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Journal of Computer and Communications 2024年第7期12卷 23-38页

作者： Ahmed S. Maklad Mohamed A. mahdy Amer Malki Noboru Niki Abdallah A. Mohamed Computer Science Department College of Computer Science and Engineering in Yanbu Taibah University Medina Saudi Arabia Information Systems Department Faculty of Computers and Artificial Intelligence Beni-Suef University Beni-Suif Egypt Computer Science Department Faculty of Computers and Artificial Intelligence Beni-Suef University Beni-Suif Egypt Institute of Advanced Science and Technology Tokushima University Tokushima Japan Information Systems Department College of Computer Science and Engineering in Yanbu Taibah University Medina Saudi Arabia Mathematics and Computer Science Department Faculty of Science Menoufia University Menoufia Egypt

In this study, a hybrid machine learning (HML)-based approach, incorporating genetic data analysis (g.a., is proposed to accurately identify the presence of adenomatous colorectal polyps (ACRP) which is a crucial early detector of colorectal cancer (CRC). The present study develops a classification ensemble model based on tuned hyperparameters. Surpassing.a.curacy percentages of early detection approaches used in previous studies, the current method exhibits exceptional performance in identifying.a.RP and diagnosing CRC, overcoming limitations of CRC traditional methods that are based on error-prone manual examination. Particularly, the method demonstrates the following CRP identification accuracy data: 97.7 ± 1.1, precision: 94.3 ± 5, recall: 96.0 ± 3, F1-score: 95.7 ± 4, specificity: 97.3 ± 1.2, average AUC: 0.97.3 ± 0.02, and average p-value: 0.0425 ± 0.07. The findings underscore the potential of this method for early detection of ACRP as well as clinical use in the development of CRC treatment planning strategies. The advantages of this approach are highly expected to contribute to the prevention and reduction of CRC mortality.

关键词： Colorectal Adenoma Detection Colorectal Cancer Diagnosis Hybrid Machine Learning genetics Analysis

Reduced differential transform and Sumudu transform methods for solving fractional financial models of awareness

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Applied Mathematics(A Journal of Chinese Universities) 2023年第3期38卷 338-356页

作者： A.M.S.mahdy K.A.gepreel Kh.Lotfy A.El-Bary Department of Mathematics and Statistics College of ScienceTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Mathematics Faculty of ScienceZagazig UniversityP.O.Box 44519ZagazigEgypt Arab Academy for Science Technology and Maritime Transport1029AlexandriaEgypt

In that paper,we new study has been carried out on previous studies of one of the most important mathematical models that describe the global economic movement,and that is described as a non-linear fractional financial model of awareness,where the studies are represented at the steps following:One:The schematic of the model is ***:The disease-free equilibrium point(DFE)and the stability of the equilibrium point are ***:The stability of the model is fulfilled by drawing the Lyapunov exponents and Poincare ***:The existence of uniformly stable solutions have ***:The Caputo is described as the fractional ***:Fractional optimal control for NFFMA is discussed by clarifying the fractional optimal control through drawing before and after ***:Reduced differential transform method(RDTM)and Sumudu Decomposition Method(SDM)are used to take the resolution of an ***,we display that SDM and RDTM are highly identical.

关键词： financial of awareness stability Lyapunov exponents Poincare map fractional optimal control Hamiltonian

Simultaneous impacts of MHD and variable wall temperature on transient mixed Casson nanofluid flow in the stag.a.ion point of rotating sphere

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Applied Mathematics and Mechanics(English Edition) 2018年第9期39卷 1327-1340页

作者： A.mahdy Department of Mathematics Faculty of Science South Valley University

A numerical analysis is provided to scrutinize time-dependent magnetohydrodynamics(MHD) free and forced convection of an electrically conducting non-Newtonian Casson nanofluid flow in the forward stag.a.ion point region of an impulsively rotating sphere with variable wall temperature. A single-phase flow of nanofluid model is reflected with a number of experimental formulae for both effective viscosity and thermal conductivity of nanofluid. Exceedingly nonlinear governing partial differential equations(PDEs)subject to their compatible boundary conditions are mutated into a system of nonlinear ordinary differential equations(ODEs). The derived nonlinear system is solved numerically with implementation of an implicit finite difference procedure merging with a technique of quasi-linearization. The controlled parameter impacts are clarified by a parametric study of the entire flow regime. It is depicted that from all the exhibited nanoparticles,Cu possesses the best convection. The surface heat transfer and surface shear stresses in the x-and z-directions are boosted with maximizing the values of nanoparticle solid volume fraction ? and rotation λ. Besides, as both the surface temperature exponent n and the Casson parameter γ upg.a.e, an enhancement of the Nusselt number is given.

关键词： single-phase nanofluid Casson transient mixed magnetohydrodynamics(MHD) non-uniform heating

An Approximate Numerical Methods for Mathematical and Physical Studies for Covid-19 Models

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Computer Systems Science & Engineering 2022年第9期42卷 1147-1163页

作者： Hammad Alotaibi Khaled A.gepreel Mohamed S.Mohamed Amr M.S.mahdy Department of Mathematics College of ScienceTaif UniversityTaif21944Saudi Arabia

The advancement in numerical models of serious resistant illnesses is a key research territory in different fields including the nature and the study of disease *** of the aims of these models is to comprehend the elements of conduction of these *** the new strain of Covid-19(Coronavirus),there has been no immunization to protect individuals from the virus and to forestall its spread so *** things being equal,control procedures related to medical services,for example,social distancing or separation,isolation,and travel limitations can be adjusted to control this *** article reveals some insights into the dynamic practices of nonlinear Coronavirus models dependent on the homotopy annoyance strategy(HPM).We summon a novel sign stream chart that is utilized to depict the Coronavirus *** the numerical investigations,it is uncovered that social separation of the possibly tainted people who might be conveying the infection and the healthy virus-free people can diminish or interrupt the spread of the *** mathematical simulation results are highly concurrent with the statistical *** free balance and dependability focus for the Coronavirus model is discussed and the presence of a consistently steady arrangement is demonstrated.

关键词： Covid-19 model optimal control existence of uniformly stable sig.a. stream chart homotopy perturbation technique

Direct-acting.a.tivirals sofosbuvir and daclatasvir attenuate carbon tetrachloride-induced liver fibrosis in mice

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Liver Research 2023年第1期7卷 71-81页

作者： Mayadah M.Abdelsalam Nageh El-mahdy Sabry Abou-Saif Department of Pharmacology and Toxicology Faculty of PharmacyTanta UniversityTantaEgypt Department of Tropical Medicine and Infectious Diseases Faculty of MedicineTanta UniversityTantaEgypt

Background and aim:Advanced liver fibrosis is a major risk for developing hepatocellular carcinoma(HCC)in chronic hepatitis C virus(HCV)***-acting.a.tivirals(DAAs)which are used for treating HCV infection,produce more than 90%cure rate but do not seem to diminish the rate of occurrence or recurrence of *** study aimed to investigate the effect of DAAs sofosbuvir(SOF)and daclatasvir(DAC)on carbon tetrachloride(CCl4)-induced fibrotic changes in ***:Eighty adult male Swiss albino mice were randomly allocated into 8 groups(10 mice/group):normal control group,SOF group(receiving SOF 80 mg/kg body weight(BW),oral gavage,daily),DAC group(receiving DAC 30 mg/kg BW,oral gavage,daily),SOF t DAC group(receiving.a.combination of both,daily),CCl4 model group(receiving CCl42 mL/kg BW,intraperitoneal twice weekly)and three CCl4-intoxicated groups receiving either SOF or DAC or their *** CCl4 groups received CCl4 for 12 weeks followed by DAAs for another 12 ***:CCl4-induced a significant elevation of alanine aminotransferase(ALT)and aspartate aminotransferase(AST),and produced histopathological evidence of fibrosis and liver degeneration along with a significant increase(P0.001)of the proliferation markers(proliferating cell nuclear antigen(PCNA)and Ki-67),hepatic stellate cells(HSCs)activation markers(alpha-smooth muscle actin(a-SMA)and glial fibrillary acidic protein(g.a.)),fibrosis marker(matrix metalloproteinase-9(MMP-9))and proinflammatory cytokine(tumor necrosis factor-alpha(TNF-a)).CCl4-intoxicated mice treated with SOF,DAC,or their combination revealed a significant amelioration(P0.001)of CCl4-induced elevation of liver enzymes,fibrotic changes,and liver degeneration along with a significant attenuation(P0.001)of CCl4-induced upregulation of all tested *** effects of SOF,DAC,and their combination on liver enzymes were comparable while the effect of SOF t DAC combination on mitigating CCl4-induced upregulation of the

关键词： Direct-acting.a.tivirals(DAAs) Sofosbuvir(SOF) Daclatasvir(DAC) Carbon tetrachloride(CCl4) Liver fibrosis Hepatocellular carcinoma(HCC)

基于Li_(2)O-NiO-P_(2)O_(5)体系的新型密封玻璃的制备与表征

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Journal of Central South University 2022年第5期29卷 1437-1446页

作者： Hany ABO-MOSALLAM Ebrahim A.mahdy g.a.s Research Department National Research CentreEl-Buhouth StDokkiCairo 12622Egypt

基于Li_(2)O-NiO-P_(2)O_(5)体系,改变氧化镍的浓度(摩尔分数从5%到15%),采用熔体淬火技术合成系列玻璃样品。XRD图谱表明含5%和10%氧化镍制备的玻璃样品具有非晶性质,在Li_(3)P和Ni_(2)P_(4)O_(12)相沉淀中镍含量高,摩尔分数高达15%。... 详细信息

基于Li_(2)O-NiO-P_(2)O_(5)体系,改变氧化镍的浓度(摩尔分数从5%到15%),采用熔体淬火技术合成系列玻璃样品。XRD图谱表明含5%和10%氧化镍制备的玻璃样品具有非晶性质,在Li_(3)P和Ni_(2)P_(4)O_(12)相沉淀中镍含量高,摩尔分数高达15%。随着镍取代锂,可以观察到玻璃化转变温度(T_g)和玻璃化软化温度(T_s)呈系统性升高。这与玻璃网格中结构的增加、结构的连惯性有关。结构研究表明,Ni^(2+)存在于八面体和四面体的位置。系列玻璃样品的密度为(2.38±0.1)~(2.46±0.1) g/cm^(3),摩尔体积为(42.28±0.1)~(39.15±0.1) cm^(3)/mol。用NiO替代Li_(2)O合成的非晶材料的溶解速率从1.53×10~(-5)降低到3.20×10^(-6 )g/(cm^(2)·min)。在25~250℃的温度范围内,玻璃的热膨胀系数从157×10^(-7)到96×10^(-7)℃^(-1)变化。所制备的玻璃有望用作低温密封材料。

关键词：玻璃密封氧化镍热膨胀溶解速率

Numerical Simulation for the Efficiency of the Produced Terahertz Radiation by Two Femtosecond Laser Pulses: Above-Threshold-Ionization

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Journal of Applied Mathematics and Physics 2023年第10期11卷 2997-3008页

作者： Abdelrahman mahdy Physics Department College of Science Jazan University Jazan 45142 Saudi Arabia

The tunneling ionization (TI) is the most dominated ionization process in the production of terahertz radiation by two femtosecond lasers, although its validity above the ionization threshold of some gases is uncertain. In the present research, we employ a 1D fluid code to simulate the efficiency of the produced terahertz radiation by two femtosecond laser beams in air plasma. Two ionization models in the context of the TI process which are the Ammosov-Delone-Krainov (ADK) for noble gases and its developed molecular ADK (MO-ADK) model for molecular gases are intrinsically used to conduct this study. The main target of the present research is to examine the validity of these models Above-Threshold-Ionization (ATI) of these gases. For this purpose, we simulated the ionization rate and the power spectrum of the produced radiation, in addition we numerically evaluated the efficiency of the produced radiation as function of the input beams intensity at particular energy fraction factor, relative phase and initial pulse duration of these beams. These calculations conducted for a selected noble gas at varying energy levels and a chosen molecular air plasma gas at different quantum numbers. Numerical results near and above the ionization threshold of the selected gases have clarified that the ADK and MO-ADK model are successful valid to study the efficiency of the produced THz radiation at low energy levels and small quantum numbers of the selected gases, meanwhile, with any further increase in the energy level and the quantum number values of these gases, both of the ADK and MO-ADK are failed to correctly analyze the efficiency process and estimate its fundamental parameters.

关键词： Terahertz Radiation Production Femtosecond Laser Computational Physics