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Mild Solutions of a Class of Conformable fractional Differential Equations with Nonlocal Conditions

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Acta Mathematicae Applicatae Sinica 2023年第2期39卷 249-261页

作者： mohamed BOUAOUID Sultan Moulay Slimane University Faculty of Sciences and TechnicsDepartment of MathematicsBP 52323000Beni MellalMorocco

This paper deals with the existence,uniqueness and continuous dependence of mild solutions for a class of conformable fractional differential equations with nonlocal initial *** results are obtained by means of the cl... 详细信息

关键词： fractional partial differential equations fractional derivatives and integrals cosine family of linear operators nonlocal conditions

Heat transfer of copper/water nanofluid flow through converging-diverging channel

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Journal of Central South University 2016年第2期23卷 484-496页

作者： mohamed Rafik SARI mohamed KEZZAR Rachid ADJABI Mechanical Engineering Department University of Skikda Industrial Mechanics Laboratory Badji-Mokhtar University of Annaba

The main objective of this work is to investigate analytically the steady nanofluid flow and heat transfer characteristics between nonparallel plane walls. Using appropriate transformations for the velocity and temperature, the basic nonlinear partial differential equations are reduced to the ordinary differential equations. Then, these equations have been solved analytically and numerically for some values of the governing parameters, Reynolds number, Re, channel half angle, α, Prandtl number, Pr, and Eckert number, Ec, using Adomian decomposition method and the Runge-Kutta method with mathematic package. Analytical and numerical results are searched for the skin friction coefficient, Nusselt number and the velocity and temperature profiles. It is found on one hand that the Nusselt number increases as Eckert number or channel half-angle increases, but it decreases as Reynolds number increases. On the other hand, it is also found that the presence of Cu nanoparticles in a water base fluid enhances heat transfer between nonparallel plane walls and in consequence the Nusselt number increases with the increase of nanoparticles volume fraction. finally, an excellent agreement between analytical results and those obtained by numerical Runge-Kutta method is highly noticed.

关键词： nanofluid flow heat transfer copper nanoparticles inclined walls analytical solution

大学生创业企业中变革型领导行为对其企业绩效的影响研究

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大学生创业企业中变革型领导行为对其企业绩效的影响研究

作者： ABDELRAHMAN nasr ABDELRAHMAN mohamed 华东师范大学

学位级别：硕士

Completed Tensor Product and flatness

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Algebra Colloquium 2020年第3期27卷 599-606页

作者： mohamed Tabaa Department of Mathematics Faculty of Sciences Mohammed v University in RabatMorocco

We give,in a more general case than the Noetherian case,an answer to the question posed by Shaul on the flatness of the completed tensor product.

关键词： preadic topology completed tensor product coherent ring flat module

A Survey of Racks and Quandles:Some Recent Developments

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Algebra Colloquium 2020年第3期27卷 509-522页

作者： mohamed Elhamdadi Department of Mathematics University of South Florida TampaFL 33620USA

This short survey contains some recent developments of the algebraic theory of racks and *** report on some elements of representation theory of quandles and ring theoretic approach to quandles.

关键词： rack quandle representation ring isomorphism

Anti-wear properties evaluation of frictional sliding interfaces in automobile engines lubricated by copper/graphene nanolubricants

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friction 2020年第5期8卷 905-916页

作者： mohamed Kamal Ahmed ALI Xianjun HOU mohamed AAABDELKAREEM Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Automotive and Tractors Engineering Department Faculty of EngineeringMinia UniversityEl-Minia 61111Egypt Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan 430070China

Owing to the significance of improving fuel economy, reducing emissions, and extending the durability of engine components, this study focused on the tribological performance of nano-additives. In this study, copper (Cu) and graphene (Gr) nanomaterials were dispersed in a fully formulated engine oil (5W-30) with different concentrations. The tribological trials were investigated under various speeds and loads, utilizing a reciprocating tribometer to mimic the ring/liner interfaces in the engine. The frictional surface morphologies were com-prehensively analyzed using electron probe X-ray microanalysis (EPMA), field emission scanning electron microscopy (fESEM), energy dispersive spectrometer (EDS), and three dimensional (3D) surface profilometry to explore the mechanisms responsible for improving the tribological performance of the frictional sliding parts in the engine. The tribological test results illustrated that lubrication by nano-additives reduced the wear rate (WR) and friction coefficient (COf) by 25%–30% and 26.5%–32.6%, respectively, as compared with 5W-30. The results showed that this is a promising approach for increasing the durability and lifespan of frictional sliding components and fuel economy in automobile engines.

关键词： engine tribology nanomaterial nanolubricant friction wear tribofilm

Robust design and analysis for opto-mechanical two array laser warning system

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Defence Technology（防务技术） 2023年第9期27卷 46-52页

作者： Mazhar Tayel mohamed Shehata mohamed Mabrouk Abdlarhman Adel mohamed Shady Shokry Mostafa Alshershby faculty of Engineering Alexandria UniversityAlexandriaEgypt Egyptian Air Defense Collage AlexandriaEgypt Laser and Optoelectronics Department Technical Research CenterEgypt

In the past three decades,laser warning systems(LWS)have emerged in great importance,as the development of laser-guided weapons,such as airborne Hellfire missiles,has increased,posing an imminent threat to vital areas and *** laser warning station(LWS)can detect,classify,identify,and give alarm from laser threat at a very short time with high ***,the designers of this system must take into account the detectability and field of view to cover the area to be *** main contribution in this research is an analytical design of LWS that consists of 24 detector elements,distributed in two arrays(2×12)***,calculating the best distance between the detectors according to the laser beam spot *** addition,enhancement laser warring sensor detection capability and detection performance fOV between the detectors to increase coverage area up to 360°.Moreover,decreasing dead zone area between the laser detectors *** calculations and illustrations made to reach the best systematic design.

关键词： LWS field of view Detector elements

Y-Shaped Intra-Scleral fixated Lens versus Retro-Pupillary Iris Claw Lens in the Treatment of Aphakia

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Open Journal of Ophthalmology 2019年第2期9卷 105-124页

作者： Ahmed mohamed Morshed Mahmoud nasr Aldeeb Adel Kamal Abdeen Salah mohamed Almosalamy Ophthalmology Department Faculty of Medicine Zagazig University Zagazig Egypt

Background: Many reasons can lead to an aphakia without adequate capsular support for implantation of a posterior chamber intraocular lens (IOL), such as intraoperative unintentional rupture of posterior capsule during phacoemulsification, planned intracapsular cataract extraction, ocular trauma and lens dislocation due to congenital and acquired causes. Purpose: To compare Y-shaped intra-scleral fixation of a posterior chamber IOL with retro pupillary fixation of an iris-claw intraocular lens (IOL) for Aphakic eyes without sufficient capsular support as respects safety, visual recovery and complications of both methods. Patients and Methods: One hundred Aphakic eyes were arbitrarily distributed between two groups. Group A included 50 eyes treated with retropupillary fixation of iris claw lens and group B included 50 eyes treated with Y-shaped intra-scleral fixation technique. Preoperative, intraoperative and postoperative data were analysed including best corrected visual acuity (BCVA), intraocular pressure (IOP), surgical time, intraoperative problems, IOL malposition and postoperative complications. following up on patients was carried out for at least six months. Results: The mean duration of surgery was 21 ± 5.3 min in group A and was 53.4 ± 6.9 min in group B (p-value 0.05). IOL tilt was found in 0 (0%) eyes in group A and in 5 (10%) eyes in group B (p 0.05). Conclusion: The results of our study indicated that both methods are satisfactory in correcting aphakia without sufficient capsular support as regards postoperative best corrected visual acuity (BCVA);however the surgical technique of retropupillary iris claw lens is easier, shorter, with low intra- and postoperative complications and safer than those used for intra-scleral fixation of IOL. But for eyes which lack both iris and capsular support, a scleral fixation of a posterior chamber IOL remains the only option.

关键词： Aphakia Iris-Claw Intraocular Lens (IOL) Y-Shaped Intra Scleral fixation

Correction:A Lightweight Approach for Skin Lesion Detection through Optimal features fusion

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Computers, Materials & Continua 2025年第1期82卷 1459-1459页

作者： Khadija Manzoor fiaz Majeed Ansar Siddique Talha Meraj Hafiz Tayyab Rauf Mohammed A.El-Meligy mohamed Sharaf Abd Elatty E.Abd Elgawad Department of Information Technology University of GujratGujrat50700Pakistan Department of Software Engineering University of GujratGujrat50700Pakistan Department of Computer Science COMSATS University Islamabad-Wah CampusWah Cantt47040Pakistan Independent Researcher BradfordBD80HSUK Advanced Manufacturing Institute King Saud UniversityRiyadh11421Saudi Arabia Department of Industrial Engineering College of EngineeringKing Saud UniversityRiyadh11421Saudi Arabia

In the article“A Lightweight Approach for Skin Lesion Detection through Optimal features fusion”by Khadija Manzoor,fiaz Majeed,Ansar Siddique,Talha Meraj,Hafiz Tayyab Rauf,Mohammed ***-Meligy,mohamed Sharaf,Abd Elatty *** Elgawad Computers,Materials&Continua,2022,Vol.70,No.1,pp.1617–***:10.32604/cmc.2022.018621,URL:https://***/cmc/v70n1/44361,there was an error regarding the affiliation for the author Hafiz Tayyab *** of“Centre for Smart Systems,AI and Cybersecurity,Staffordshire University,Stoke-on-Trent,UK”,the affiliation should be“Independent Researcher,Bradford,BD80HS,UK”.

关键词： fusion Skin feature