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MHD Boundary Layer Flow of a Power-Law Nanofluid Containing Gyrotactic Microorganisms Over an Exponentially Stretching Surface

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Computers, Materials & Continua 2020年第2期62卷 525-549页

作者： Mohamed Abd El-Aziz A.M.aly Department of Mathematics Faculty of ScienceKing Khalid UniversityAbha61411Saudi Arabia Department of Mathematics Faculty of ScienceHelwan UniversityHelwan-Cairo11795Egypt Department of Mathematics Faculty of ScienceSouth Valley UniversityQena83523Egypt

This study focusses on the numerical investigations of boundary layer flow for magnetohydrodynamic(MHD)and a power-law nanofluid containing gyrotactic microorganisms on an exponentially stretching surface with zero nanoparticle mass flux and convective *** nonlinear system of the governing equations is transformed and solved by Runge-Kutta-Fehlberg *** impacts of the transverse magnetic field,bioconvection parameters,Lewis number,nanofluid parameters,Prandtl number and power-law index on the velocity,temperature,nanoparticle volume fraction,density of motile microorganism profiles is *** addition,the impacts of these parameters on local skin-friction coefficient,local Nusselt,local Sherwood numbers and local density number of the motile microorganisms are *** results reveal that the power law index is considered an important factor in this *** to neglecting the buoyancy force term,the bioconvection and nanofluid parameters have slight effects on the velocity *** resultant Lorentz force,from increasing the magnetic field parameter,try to decrease the velocity profiles and increase the rescaled density of motile microorganisms,temperature and nanoparticle volume fraction ***,an augmentation of power-law index drops the reduced local skin-friction and reduced Sherwood number,while it increases reduced Nusselt number and reduced local density number of motile microorganisms.

关键词： Bioconvection gyrotactic microorganisms magnetohydrodynamic nanofluid boundary layer power-law

Entropy Generation for Flow and Heat Transfer of Sisko-Fluid Over an Exponentially Stretching Surface

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Computers, Materials & Continua 2020年第1期62卷 37-59页

In the present study,the effects of the magnetic field on the entropy generation during fluid flow and heat transfer of a Sisko-fluid over an exponentially stretching surface are *** similarity transformations are used to transfer the governing partial differential equations into a set of nonlinear-coupled ordinary differential ***-Kutta-Fehlberg method is used to solve the governing *** effects of magnetic field parameter,local slip parameterλ,generalized Biot numberγ,Sisko fluid material parameter,Eckert number Ec,Prandtl number Pr and Brinkman number Br at two values of power law index on the velocity,temperature,local entropy generation number N_(G) and Bejan number Be are ***,the tabular forms for local skin friction coefficient and local Nusselt number under the effects of the physical parameters are *** current results are helpful in checking the entropy generation for *** is found that,an extra magnetic field parameter makes higher Lorentz force that suppresses the *** shear thinning fluids(n<1),the temperature dominates and the velocity *** entropy generation number is more for larger generalized Biot number,magnetic field parameter and Brinkman *** local skin friction coefficient increases as magnetic field parameter and material parameter are increase and it decreases as local slip parameter *** local Nusselt number decreases as magnetic field parameter,local slip parameter and Eckert number are increase,while it increases as material parameter,generalized Biot number and Prandtl number are increase.

关键词： Boundary layer entropy generation exponentially stretching surface magnetic field sisko-fluid

Dispersive soliton solutions for shallow water wave system and modified Benjamin-Bona-Mahony equations via applications of mathematical methods

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Journal of Ocean Engineering and Science 2021年第1期6卷 85-98页

作者： Asghar Ali aly R.Seadawy Mathematics Department University of EducationLahorePakistan Mathematics Department Faculty of ScienceTaibah UniversityAl-Madinah Al-MunawarahSaudi Arabia

We have utilized three novel methods,called generalized direct algebraic,modified F-expansion and improved simple equation methods to construct traveling wave solutions of the system of shallow water wave equations and modified Benjamin-Bona-Mahony *** substituting particular values of the parameters,different solitary wave solutions are derived from the exact traveling wave *** is shown that these employed methods are more powerful tools for nonlinear wave equations.

关键词： System of shallow water wave equations Modified Benjamin-Bona-Mahony equation Generalized direct algebraic method Improved simple equation method Modified F-expansion method Traveling wave solutions Solitary wave solutions

Stem cells:Sources, and regenerative therapies in dental research and practice

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World Journal of Stem Cells 2015年第7期7卷 1047-1053页

作者： Lobna Abdel Aziz aly Oral and Maxillofacial Surgery Faculty of DentistryFuture University

Stem cells are considered to be among the principle scientific breakthroughs of the twentieth century for the future of medicine, and considered to be an important weapon to fight against diseases, particularly those that have resisted the efforts of science for a long time. Human dental tissues have limited potentials to regenerate but the discovery of dental stem cells have developed new and surprising scenario in regenerative dentistry. Stem cell treatments are one example of thepossibility using adult cells sourced from patients' own bodies' means that it can be expected that in the near future such treatments may become routine at dental practices. The hope is that it will become possible to regenerate bone and dental tissues including the periodontal ligament, dental pulp and enamel, and that the creation of new teeth may also become feasible. In view of this possibility of achieving restoration with regenerative medicine, it can be considered that a new era of dentistry is beginning. Thus the aim of this review is to give dental professionals a brief overview of different stem cells sources and the latest findings and their implications for improving oral health and treating certain conditions of the human mouth and face.

关键词： Stem cells Regeneration Dental research

Framework for COVID-19 Segmentation and Classification Based on Deep Learning of Computed Tomography Lung Images

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Journal of Electronic Science and Technology 2022年第3期20卷 246-256页

作者： Wessam M.Salama Moustafa H.aly the Department of Basic Science Faculty of EngineeringPharos UniversityAlexandria12455Egypt the Department of Electronics and Communications Engineering College of Engineering and TechnologyArab Academy for ScienceTechnology and Maritime TransportAlexandria1029Egypt

Corona Virus Disease 2019(COVID-19) has affected millions of people worldwide and caused more than6.3 million deaths(World Health Organization, June 2022). Increased attempts have been made to develop deep learning methods to diagnose COVID-19 based on computed tomography(CT) lung images. It is a challenge to reproduce and obtain the CT lung data, because it is not publicly available. This paper introduces a new generalized framework to segment and classify CT images and determine whether a patient is tested positive or negative for COVID-19 based on lung CT images. In this work, many different strategies are explored for the classification ***50 and VGG16 models are applied to classify CT lung images into COVID-19 positive or negative. Also,VGG16 and ReNet50 combined with U-Net, which is one of the most used architectures in deep learning for image segmentation, are employed to segment CT lung images before the classifying process to increase system performance. Moreover, the image size dependent normalization technique(ISDNT) and Wiener filter are utilized as the preprocessing techniques to enhance images and noise suppression. Additionally, transfer learning and data augmentation techniques are performed to solve the problem of COVID-19 CT lung images deficiency, therefore the over-fitting of deep models can be avoided. The proposed frameworks, which comprised of end-to-end, VGG16,ResNet50, and U-Net with VGG16 or ResNet50, are applied on the dataset that is sourced from COVID-19 lung CT images in Kaggle. The classification results show that using the preprocessed CT lung images as the input for U-Net hybrid with ResNet50 achieves the best performance. The proposed classification model achieves the 98.98%accuracy(ACC), 98.87% area under the ROC curve(AUC), 98.89% sensitivity(Se), 97.99 % precision(Pr), 97.88%F-score, and 1.8974-seconds computational time.

关键词： Augmentation classification computed tomography(CT) Corona Virus Disease 2019(COVID-19) deep learning ResNet50 segmentation U-Net VGG16

The effect of multi-intermediate bands on the behavior of an InAs_(1-x)N_x/GaAs(1-y)Sb_y quantum dot solar cell

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Journal of Semiconductors 2015年第4期36卷 1-6页

作者： Abou El-Maaty M.aly A.Nasr Power Electronics and Energy Conversion Department ERINRCB College of Computer Qassim University Radiation Engineering Department NCRRTAtomic Energy Authority

A mathematical model of quantum dot intermediate band solar cells （QDIBSCs） is investigated using two intermediate bands （IBs）. These two IBs arise from the quantum dot （QD） semiconductor material within the bandgap energy. Some parameters such as the width of the QD （WQD） and the barrier thickness or the inter-dot distances between the QDs （BT） are studied to show their influence on the performance of the QDIBSC. The timeindependent Schr6dinger equation, which is solved using the Kronig-Penney model, is used to determine the posi- tion and bandwidth energies of the two IBs. In our proposed model, the cubic shape of the QDs from InAs0.9N0.1 and the barrier or host semiconductor material from GaAs0.98Sb0.02 are utilized. It is shown from the results obtained that changing the parameters WQD and Bx has more influence on the bandwidth energy for the first IB, A 1, than in the case of the second IB, A2. The optimum power conversion efficiencies （PCEs） of the QDIBSCs with two IBs for the model under study are 58.01% and 73.55% at 1 sun and maximum solar concentration, respectively. One can observe that, in the case of the two IBs, an improvement of the PCE is achieved.

关键词： intermediate bands solar cells quantum dots efficiency solar concentration

Optical soliton and elliptic functions solutions of Sasa-satsuma dynamical equation and its applications

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Applied Mathematics(A Journal of Chinese Universities) 2021年第2期36卷 229-242页

作者： aly R.Seadawy Naila Nasreen LU Dian-chen Mathematics department Faculty of scienceTaibah UniversityAI-Madinah Al-MunawarahSaudi Arabia Faculty of Science Jiangsu UniversityZhenjiang 212013China

The Sasa-satsuma(SS)dynamical equation interpret propagation of ultra-short and femto-second pulses in optical *** dynamical model has important physical *** this article,two mathematical techniques namely,improved F-expansion and improved aux-iliary methods are utilized to construct the several types of solitons such as dark soliton,bright soliton,periodic soliton,Elliptic function and solitary waves solutions of Sasa-satsuma dynamical *** results have imperative applications in sciences and other fields,and construc-tive to recognize the physical structure of this complex dynamical *** computing work and obtained results show the infuence and effectiveness of current methods.

关键词： Sasa-Satsuma equation improved F-expansion and auxiliary equation methods solitons elliptic function and periodic solutions

Natural Convection in an H-Shaped Porous EnclosureFilled with a Nanofluid

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Computers, Materials & Continua 2021年第3期66卷 3233-3251页

作者： Zehba A.S.Raizah Abdelraheem M.aly Department of Mathematics College of ScienceKing Khalid UniversityAbha62529Saudi Arabia Department of Mathematics South Valley UniversityQena83523Egypt

This study simulates natural convection flow resulting from heat partitions in an H-shaped enclosure filled with a nanofluid using an incompressible smoothed particle hydrodynamics(ISPH)*** right area of the H-shaped enclosure is saturated with non-Darcy porous *** center variable partitions of the H-shaped enclosure walls are kept at a high-temperature *** left and right walls of the H-shaped enclosure are positioned at a low temperature Tc and the other walls are *** ISPH method,the source term in pressure Poisson equation(PPE)is *** influences of the controlling parameters on the temperature distributions,the velocity field and average Nusselt number are *** performed simulations proofed that the length of the heated partitions augments the velocity field and temperature distributions in an H-shaped *** number rises the fluid velocity and heat transfer in an H-shaped *** porous layer on the right side of the H-shaped enclosure at a lower Darcy parameter causes a high resistance force for the fluid flow and heat transfer characteristic inside an H-shaped *** nanoparticles reduces the velocity field and enhances the heat transfer inside an H-shaped enclosure.

关键词： H-shaped enclosure ISPH natural convection nanofluid porous medium

a.alytical Solution for Peristaltic Transport of Viscous Nanofluid in an Asymmetric Channel with Full Slip and Convective Conditions

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Communications in Theoretical Physics 2017年第7期67卷 96-102页

作者： Abdelhalim Ebaid Emad H. aly K. Vajravelu Department of Mathematics Faculty of Science University of Tabuk Tabuk 71491 Saudi Arabia Department of Mathematics Faculty of Science University of Jeddah Jeddah 21589 Saudi Arabia Department of Mathematics Faculty of Education Ain Shams University Roxy 11757 Cairo Egypt Department of Mathematics Department of Mechanical Materials and Aerospace Engineering University of Central Florida Orlando FL 32816 USA

The peristaltic ttow of nanofluids is a relatively new area of research. Scientists are of the opinion that the no-slip conditions at the boundaries are no longer valid and consequently, the first and the second order slip conditions should be addressed. In this paper, the effects of slip conditions and the convective boundary conditions at the boundary walls on the peristaltic flow of a viscous nanofluid are investigated for. Also, the exact a.alytical solutions are obtained for the model. The obtained results are presented through graphs and discussed. The results reveal that the two slip parameters have strong effects on the temperature and the nanoparticles volume fraction profiles. Moreover, it has been seen that the temperature and nanoparticles volume fraction profiles attain certain values when the first slip condition exceeds a specified value. However, no limit value for the second slip parameter has been detected. Further, the effects of the various emerging parameters on the flow and heat transfer characteristics have been presented.

关键词： nanofluid peristaltic flow slip model convective conditions asymmetric channel