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Transactions of Nonferrous Metals Society of China 2015年第12期25卷 3865-3876页

作者： Mohamed Ibrahim abd el AAL M.M.SADAWY Mechanical Design and Production Department Faculty of Engineering Zagazig University Mining and Petroleum Engineering Department Al-Azhar University

Pure aluminum samples were processed by equal channel angular pressing（ECAP） up to 10 passes at room temperature. The effects of the ECAP number of passes on the microstructure evolution, the mechanical properties, deformation homogeneity and corrosion behavior of the processed samples were fully investigated. The imposed strain resulted in an obvious reduction in the grain size from 390 μm before ECAP down to 1.8, 0.4, and 0.3 μm after ECAP up to 2, 4 and 10 passes, respectively. The microhardness, deformation homogeneity and tensile strength were increased while the elongation decreased with the increase of ECAP number of passes. Immersion tests, open circuit potential, Tafel polarization, cyclic polarization and potentiostatic measurements in 3.5% Na Cl solution revealed an obvious improvement in the corrosion resistance of ECAP processed samples compared with the as-cast sample. The increase of the number of passes can be used successfully in producing ultra-fine grained（UfG） bulk pure aluminum sample with a high misorientation angle, reasonably high mechanical properties and corrosion resistance.

关键词： equal channel angular pressing(ECAP) microstructure mechanical properties corrosion resistance passive film pitting

Efficient Deep CNN Model for COVID-19 Classification

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Computers, Materials & Continua 2022年第3期70卷 4373-4391页

作者： Walid el-Shafai Amira A.Mahmoud el-Sayed M.el-Rabaie Taha E.Taha Osama f.Zahran Adel S.el-fishawy Mohammed abd-elnaby fathi E.abd el-Samie Department electronics and electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Security Engineering Lab Computer Science DepartmentPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Computer Engineering College of Computers and Information TechnologyTaif UniversityTaif21944Saudi Arabia Department of Information Technology College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadh84428Saudi Arabia

Coronavirus(COVID-19)infection was initially acknowledged as a global pandemic in Wuhan in *** Health Organization(WHO)stated that the COVID-19 is an epidemic that causes a 3.4%death *** X-Ray(CXR)and Computerized Tomography(CT)screening of infected persons are essential in diagnosis *** are numerous ways to identify positive COVID-19 *** of the fundamental ways is radiology imaging through CXR,or CT *** comparison of CT and CXR scans revealed that CT scans are more effective in the diagnosis process due to their high ***,automated classification techniques are required to facilitate the diagnosis *** Learning(DL)is an effective tool that can be utilized for detection and classification this type of medical *** deep Convolutional Neural Networks(CNNs)can learn and extract essential features from different medical image *** this paper,a CNN architecture for automated COVID-19 detection from CXR and CT images is *** activation functions as well as three optimizers are tested and compared for this *** proposed architecture is built from scratch and the COVID-19 image datasets are directly fed to train *** performance is tested and investigated on the CT and CXR *** activation functions:Tanh,Sigmoid,and RelU are compared using a constant learning rate and different batch *** optimizers are studied with different batch sizes and a constant learning ***,a comparison between different combinations of activation functions and optimizers is presented,and the optimal configuration is ***,the main objective is to improve the detection accuracy of COVID-19 from CXR and CT images using DL by employing CNNs to classify medical COVID-19 images in an early *** proposed model achieves a classification accuracy of 91.67%on CXR image dataset,and a classification accuracy of 100%on CT dataset with training times of 58 min and 46 min on CXR an

关键词： COVID-19 image classification CNN DL activation functions optimizers

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

fractional Optimal Control of Navier-Stokes Equations

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Computers, Materials & Continua 2020年第8期64卷 859-870页

作者： abd-Allah Hyder M.el-Badawy King Khalid University College of ScienceDepartment of MathematicsP.O.Box 900461413AbhaSaudi Arabia Department of Engineering Mathematics and Physics Faculty of EngineeringAl-Azhar UniversityCairo11371Egypt Mathematics Department Al-Azhar UniversityCairoEgypt

In this paper,the non-stationary incompressible fluid flows governed by the Navier-Stokes equations are studied in a bounded *** study focuses on the time-fractional Navier-Stokes equations in the optimal control subject,where the control is distributed within the domain and the time-fractional derivative is proposed as Riemann-Liouville *** addition,the control object is to minimize the quadratic cost *** using the Lax-Milgram lemma with the assistance of the fixed-point theorem,we demonstrate the existence and uniqueness of the weak solution to this ***,for a quadratic cost functional subject to the time-fractional Navier-Stokes equations,we prove the existence and uniqueness of optimal ***,via the variational inequality upon introducing the adjoint linearized system,some inequalities and identities are given to guarantee the first-order necessary optimality conditions.A direct consequence of the results obtained here is that when a→1,the obtained results are valid for the classical optimal control of systems governed by the Navier-Stokes equations.

关键词： Optimal control lax-milgram lemma fixed point theorem navier-stokes equations

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(nelocity *** 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

Primary Hyperoxaluria Type 1 in Adulthood: Case Series

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Open Journal of Nephrology 2024年第3期14卷 350-360页

作者： Sara el Maakoul Nada el Kadiri Nabil Hmaidouch Salma Belmokadem Loubna Benamar Tarik Bouattar Naima Ouzeddoun Department of Nephrology Dialysis Renal Transplantation Ibn Sina University Hospital-Rabat Rabat Morocco faculty of Medicine and Pharmacy Mohammed V University Rabat Morocco

Introduction: Primary hyperoxaluria type 1 (HP1) is a rare lithiasis with systemic involvement, due to the accumulation of calcium oxalate crystals. In the absence of therapeutic management, it progresses to end-stage chronic renal failure. The aim of this study is to describe and analyse the observations of our patients with HP1. Patients and methods: This is a retrospective study carried out between 2014 and 2023 in the Nephrology-Dialysis Transplant Department of the Ibn Sina University Hospital in Rabat. The clinical, paraclinical and evolutionary elements were taken from the patients’ medical records. Results: We collected 11 cases, with a mean age of 27 ± 8.5 years and a M/f sex ratio of 1.7. The diagnosis of HP1 was made on the basis of genetic analysis in 8 patients, morphological and spectro-photometric analysis of the calculus in one patient, biopsy of the graft in one patient and crystalluria and a family history of PH1 in one patient. Two patients died, and 8 patients were on chronic haemdialysis with systemic damage. Only one patient maintained a stable GfR at 60 ml/min. Conclusion: Early diagnosis combined with conservative treatment is the only way to limit the rapid progression of this disease. This requires awareness and collaboration between nephrologists, urologists and biologists within a specialised team.

关键词： Primary Hyperoxaluria Adulthood Kidney Disease

Physio-biochemical and nutrient constituents of peanut plants under bentazone herbicide for broad-leaved weed control and water regimes in dry land areas

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Journal of Arid Land 2020年第4期12卷 630-639页

作者： Hani S SAUDY Ibrahim M el–METWALLY Goma A abd el–SAMAD Agronomy Department Faculty of AgricultureAin Shams University68–Hadayek Shoubra 11241CairoEgypt Botany Departments National Research CentreEl–Behos St.Dokki 12622CairoEgypt

The abundance of broad-leaved weeds in peanut fields represents the handicap in weed management programs, since limited specific herbicides can be recommended to control them. Moreover, the physio-biochemical constituents and nutritional status in peanut plants as affected by available herbicides, i.e., bentazone under water stress conditions are not well known. Therefore, field trials were conducted during the growing seasons in 2016 and 2017 to investigate the interactional impact of irrigation levels(I_(50), I_(75) and I_(100), representing irrigation by 50%, 75% and 100% of crop evapotranspiration, respectively) and weed control practices(bentazone, bentazone+hoeing once, hoeing twice and weedy check as control) on dominant broad-leaved weeds as well as peanut physiological and agronomic traits. Result indicated that the efficiency of weed control for each weeded treatment under I_(50) significantly equaled with its counterpart under I_(75) or I_(100). Bentazone+hoeing once diminished weed biomass by 89.3% and enhanced chlorophyll content of peanut plants by 51.2%. Bentazone relatively caused a reduction in carotenoides. Hoeing twice and bentazone+hoeing once under I_(100) in both growing seasons as well as hoeing twice under I_(75) in 2017 were the superior combinations for boosting pod yield of peanut plants. Treatment of bentazone+hoeing once and I_(75) recorded the lowest reduction in N utilization percentage and the highest increase in potassium utilization percentage of peanut plants. eliminating weeds enhanced water use efficiency by 37.8%, 49.6% and 34.7% under I_(50), I_(75) and I_(100), respectively. In conclusion, peanut seems to be tolerant to bentazone at moderate water supply, thus it can be safely used in controlling the associated broad-leaved weeds.

关键词： biochemical traits drought nutritional status peanut productivity weed growth

Sedimentation Processes at the Navigation Channel of the Liquefied Natural Gas (LNG) Port, Nile Delta, Egypt

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International Journal of Geosciences 2010年第1期1卷 14-20页

作者： Essam abd el-halim Mohamed Deabes Physical Oceanography Department Coastal Research Institute (CoRI)

Liquefied Natural Gas (LNG) port is located at Abu Qir Bay on the northwestern coast of the Nile delta, Egypt. The port was constructed in 2004 to export liquefied natural gas worldwide. The offshore basins of this port including the turning and berthing areas (15-m depth) are connected to the deep water by a 15-m depth dredged channel that extends 4 km offshore. However, the navigation channel and its contiguous basins have experienced problematic shoaling that might affect the navigation activities of gas tankers. Sedimentation processes have been investigated by analyses of waves, currents, bathymetry, grain size of seabed and channel dimensions. Sedimentation rates are estimated using a developed numerical model. Sedimentation rate fluctuates between 0.048 × 106 m3/month and 0.388 × 106 m3/month, with an annual sedimentation rate of 1.977 × 106 m3/yr. The variance in the sedimentation rates between winter and summer resulted in increasing of current speed and direction flowing towards offshore. The sedimentation process is influenced by the temporal variability in the direction and intensity of the predominant waves, currents, orientation of navigation channel, basin breakwaters, seafloor morphology and sediment sources. Due to the geographic location of LNG port it lays within a sediment sink for sediments supplied from different alternating directions by several pathways, flowing towards the N-W, S-W, N-E, and S-E quadrants. Most of these currents components are substantially effective in transporting fine-grained sediment towards the navigation channel axis and contiguous basins. Together with these currents, the predominant NW and SE waves acting to agitate and stirrup sediments in the vicinity of the port, and thereby accelerating sedimentation rates.

关键词： Sedimentation Rate Nile Delta Navigation Channel Bed Load Suspended Load and Sediment Transport

Early diagnostic evaluation of miR-122 and miR-224 as biomarkers for hepatocellular carcinoma

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Genes & Diseases 2017年第4期4卷 215-221页

作者： Khalda S.Amr hanan abd elmawgoud Atia Rehab abd elazeem elbnhawy Wafaa M.Ezzat Medical Molecular Genetics Department National Research CentreCairoEgypt Biochemistry Department Faculty of Pharmacy(Girls)Al-Azhar UniversityCairoEgypt Urology and Nephrology Center Mansoura UniversityMansouraEgypt Internal Medicine Department National Research CenterCairoEgypt

Hepatocellular carcinoma(HCC)is one of the common lethal types of tumor all over the *** lethality of HCC accounts for many *** of them,the lack of reliable diagnostic markers at the early stage,in this context,serum miRNAs became promising diagnostic ***,we aimed to identify the predictive value of two miRNAs(miR-122 and miR-224)in plasma of patients with HCC preceded by chronic HCV *** miRNA assays specific for hsa-miR-122 and hsa-miR-224 were used to assess the expression levels of the chosen miRNAs in plasma samples collected from three groups;40 patients with HCC related to HCV,40 with CHC patients and 20 healthy *** study revealed that the mean plasma values of miRNA-122 were significantly lower among HCC group when compared to CHC and control groups(Pficantly higher among HCC group when compared to both CHC group and control ***,it was found that miR-122 can predict development of HCC at cut-off valueelopment of HCC at cut-off value>1.2(RQ)and(AUC Z 0.93,Pf AfP to diagnose HCC was(AUC:0.619;P Z 0.06).In conclusion,the expression plasma of miR-122 and miR-224 could be used as noninvasive biomarkers for the early prediction of developing HCC at the early stage.

关键词： Diagnosis Hepatocellular carcinoma miR-122 miR-224 Sensitivity

Proposed Privacy Preservation Technique for Color Medical Images

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Intelligent Automation & Soft Computing 2023年第4期36卷 719-732页

作者： Walid el-Shafai Hayam A.abd el-Hameed Noha A.el-Hag Ashraf A.M.Khalaf Naglaa f.Soliman Hussah Nasser AlEisa fathi E.abd el-Samie Department of electronics and electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Security Engineering Laboratory Department of Computer SciencePrince Sultan UniversityRiyadh11586Saudi Arabia electrical Communications Engineering Department Faculty of EngineeringMinia UniversityMinia61111Egypt Higher Institute of Commercial Science Management Information SystemsEl-Mahala El-KobraEgypt Department of Information Technology College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadhSaudi Arabia

Nowadays,the security of images or information is very *** paper introduces a proposed hybrid watermarking and encryption technique for increasing medical image ***,the secret medical image is encrypted using Advanced Encryption Standard(AES)***,the secret report of the patient is embedded into the encrypted secret medical image with the Least Signiﬁcant Bit(LSB)watermarking *** that,the encrypted secret medical image with the secret report is concealed in a cover medical image,using Kekre’s Median Codebook Generation(KMCG)***,the stego-image obtained is split into 16 ***,it is sent to the *** adopt this strategy to send the secret medical image and report over a network *** proposed technique is assessed with different encryption quality metrics including Peak Signal-to-Noise Ratio(PSNR),Correlation Coefﬁcient(Cr),fea-ture Similarity Index Metric(fSIM),and Structural Similarity Index Metric(SSIM).Histogram estimation is used to conﬁrm the matching between the secret medical image before and after *** results demonstrate that the proposed technique achieves good performance with high quality of the received medical image and clear image details in a very short processing time.

关键词： LSB steganography AES algorithm KMCG algorithm