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Journal of Central South University 2015年第5期22卷 1606-1613页

作者： ibrahim a.abbas Department of Mathematics Faculty of Science and Arts - Khulais University of Jeddah Nonlinear Analysis and Applied Mathematics Research Group (NAAM) Department of MathematicsKing Abdulaziz University Department of Mathematics Faculty of Science Sohag University

The present work is concerned with the solution of a problem on thermoelastic interactions in a functional graded material due to thermal shock in the context of the fractional order three-phase lag model. The governing equations of fractional order generalized thermoelasticity with three-phase lag model for functionally graded materials(FGM)(i.e., material with spatially varying material properties) are established. The analytical solution in the transform domain is obtained by using the eigenvalue *** inversion of Laplace transform is done numerically. The graphical results indicate that the fractional parameter has significant effects on all the physical quantities. Thus, we can consider the theory of fractional order generalized thermoelasticity an improvement on studying elastic materials.

关键词： three-phase lag model fimctionally graded materials fractional calculus generalized thermoelasticity

Interaction due to various sources in saturated porous media with incompressible fluid

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Journal of Central South University 2016年第5期23卷 1232-1242页

作者： Rajneesh Kumar ibrahim a.abbas Department of Mathematics Kurukshetra University Department of Mathematics Faculty of Science and Arts-KhulaisUniversity of Jeddah Nonlinear Analysis and Applied Mathematics Research Group (NAAM) Department of MathematicsKing Abdulaziz University Department of Mathematics Faculty of ScienceSohag University

The disturbance due to mechanical and thermal sources in saturated porous media with incompressible fluid for two-dimensional axi-symmetric problem is *** Laplace and Hankel transforms techniques are used to investigate the *** concentrated source and source over circular region have been taken to show the utility of the *** transformed components of displacement,stress and pore pressure are *** inversion techniques are used to obtain the resulting quantities in the physical domain and the effect of porosity is shown on the resulting *** the field quantities are found to be sensitive towards the porosity *** is observed that porosity parameters have both increasing and decreasing effect on the numerical values of the physical *** the values of the physical quantities are affected by the different boundaries.A special case of interest is also deduced.

关键词： axi-symmetry incompressible porous medium pore pressure Laplace transform Hankel transform concentrated source and source over circular region

Generalized thermoelasticity of the thermal shock problem in an isotropic hollow cylinder and temperature dependent elastic moduli

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Chinese Physics B 2012年第1期21卷 289-294页

作者： ibrahim a.abbas Mohamed I.A.Othman Department of Mathematics Faculty of Science and Arts-KhulaisKing AbdulAziz UniversityJeddahSaudi Arabia Department of Mathematics Faculty of ScienceSohag UniversitySohagEgypt Department of Mathematics Faculty of ScienceZagazig UniversityP.O.Box 44519ZagazigEgypt

In this paper, we construct the equations of generalized thermoelasicity for a non-homogeneous isotropic hollow cylider with a variable modulus of elasticity and thermal conductivity based on the Lord and Shulman theory. The problem has been solved numerically using the finite element method. Numerical results for the displacement, the temperature, the radial stress, and the hoop stress distributions are illustrated graphically. Comparisons are made between the results predicted by the coupled theory and by the theory of generalized thermoelasticity with one relaxation time in the cases of temperature dependent and independent modulus of elasticity.

关键词： generalized thermoelsticity thermal shock temperature dependent elastic moduli finiteelement method

Response of thermal source in a transversely isotropic thermoelastic half-space with mass diffusion by using a finite element method

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Chinese Physics B 2012年第8期21卷 307-313页

作者： ibrahim a.abbas Rajneesh Kumar Vijay Chawla Department of Mathematics Faculty of Science and Arts-KhulaisKing Abdulaziz UniversityJeddahSaudi Arabia Department of Mathematics Faculty of ScienceSohag UniversitySohagEgypt Department of Mathematics Kurukshetra UniversityKurukshetra-136119HaryanaIndia

The two-dimensional problem of generalized thermoelastic diffusion material with thermal and diffusion relaxation times is investigated in the context of the Lord-Shulman theory. As an application of the problem, a particular type of thermal source is considered and the problem is solved numerically by using a finite element method. The components of displacement, stress, temperature distribution chemical potential and mass concentration are obtained. The resulting quantities are depicted graphically for a special model. An appreciable effect of relaxation times is observed on various resulting quantities.

关键词： thermoelastic diffusion thermal source finite element method relaxation time

Effects of magnetohydrodynamic flow past a vertical plate with variable surface temperature

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Applied Mathematics and Mechanics(English Edition) 2010年第3期31卷 329-338页

作者： ibrahim a.abbas G.PALANI Department of Mathematics Faculty of Sciences and ArtsNajran University Department of Mathematics Faculty of ScienceSohag University Department of Mathematics S.S.Govt.Arts College

An analysis is performed to study the magnetohydrodynamic flow of an electrically conducting, viscous incompressible fluid past a semi-infinite vertical plate with variable surface temperature under the action of transversely applied magnetic field. The heat due to viscous dissipation and the induced magnetic field are assumed to be negligible. The dimensionless governing equations are unsteady, two-dimensional, coupled and non-linear governing equations. It is found that the magnetic field parameter has a retarding effect on the velocities of air and water.

关键词： finite element vertical plate skin friction velocity Nusselt number

Congruent Feature Selection Method to Improve the Efficacy of Machine Learning-Based Classification in Medical Image Processing

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 357-384页

作者： Mohd Anjum Naoufel Kraiem Hong Min Ashit Kumar Dutta Yousef ibrahim Daradkeh Department of Computer Engineering Aligarh Muslim UniversityAligarh202002India College of Computer Science King Khalid UniversityAbha61413Saudi Arabia School of Computing Gachon UniversitySeongnam13120Republic of Korea Department of Computer Science and Information Systems College of Applied SciencesAlMaarefa UniversityRiyadh13713Saudi Arabia Department of Computer Engineering and Information College of Engineering in Wadi AlddawasirPrince Sattam bin Abdulaziz UniversityAl-Kharj16273Saudi Arabia

Machine learning(ML)is increasingly applied for medical image processing with appropriate learning *** applications include analyzing images of various organs,such as the brain,lung,eye,etc.,to identify specific flaws/diseases for *** primary concern of ML applications is the precise selection of flexible image features for pattern detection and region *** of the extracted image features are irrelevant and lead to an increase in computation ***,this article uses an analytical learning paradigm to design a Congruent Feature Selection Method to select the most relevant image *** process trains the learning paradigm using similarity and correlation-based features over different textural intensities and pixel *** similarity between the pixels over the various distribution patterns with high indexes is recommended for disease ***,the correlation based on intensity and distribution is analyzed to improve the feature selection ***,the more congruent pixels are sorted in the descending order of the selection,which identifies better regions than the ***,the learning paradigm is trained using intensity and region-based similarity to maximize the chances of ***,the probability of feature selection,regardless of the textures and medical image patterns,is *** process enhances the performance of ML applications for different medical image *** proposed method improves the accuracy,precision,and training rate by 13.19%,10.69%,and 11.06%,respectively,compared to other models for the selected *** mean error and selection time is also reduced by 12.56%and 13.56%,respectively,compared to the same models and dataset.

关键词： Computer vision feature selection machine learning region detection texture analysis image classification medical images

Efficacy of extract from Ononis spinosa *** ethanol-induced gastric ulcer in rats

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Journal of Traditional Chinese Medicine 2021年第2期41卷 270-275页

作者： Manal Ahmad abbas Yasser ibrahim Kandil Manal Mohammad abbas Faculty of Allied Medical Sciences Al-Ahliyya Amman UniversityAmman 19328Jordan Biochemistry Department Faculty of PharmacyAl-Azhar UniversityCairo 11884Egypt

OBJECTIVE:To investigate the efficacy of the extract from Ononis spinosa L.(***)on ethanol-induced gastric ulcer in ***:Phytochemical constituents of the extract from *** were analyzed using liquid chromatography-mass *** were classified into 4 equal groups;ulcer control received oral vehicle;positive control was administered with 40 mg/kg esomeprazole(standard drug)and 2 groups received 0.5 and 1 g/kg of *** extract,*** ulcer was induced by absolute ethanol(5 mL/kg)orally to all *** of ulcer index,cyclooxygenase-2(COX-2)expression and determination of total glutathione level in gastric mucosa were ***:Oral administration of the extract from *** at doses 0.5 and 1 g/kg lowered the ulcer indices by 80.39%and 98.71%,respectively,compared to 67.89%by esomeprazole(40 mg/kg).Histologically,treatment with the extract decreased necrosis and hemorrhage in mucosa and edema and infiltration by inflammatory cells in *** immunohistochemical technique,it was demonstrated that COX-2 expression increased in mucosa of animals treated with the extract as well as by *** and esomeprazole increased total glutathione level in the stomach compared to *** was the major compound of the extract followed by trifolirhizin,myricitrin,gentisic acid,cycloartenol and ***:The present study demonstrated that the extract from *** was able to protect gastric mucosa from ethanol injury by at least 2 mechanisms,namely the induction of COX-2 and decreasing oxidative stress in the stomach.

关键词： Ononis Stomach ulcer Cyclooxygenase 2 Ethanol Ulcer index

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Microwave-assisted solvent extraction of castor oil from castor seeds

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Chinese Journal of Chemical Engineering 2018年第12期26卷 2516-2522页

作者： Nur Atirah ibrahim Muhammad abbas Ahmad Zaini Centre of Lipids Engineering & Applied Research (CLEAR) Ibnu-Sina Institute for Scientific & Industrial Research Universiti Teknologi Malaysia 81310 UTM Johor Bahru Johor Malaysia School of Chemical & Energy Engineering Faculty of Engineering Universiti Teknologi Malaysia

This study was aimed at evaluating the physicochemical properties and oxidation stability of castor oil using microwave-assisted solvent extraction(MAE). MAE was performed using 5% ethanol in hexane as solvent at different extraction times, power intensities and solvent-to-feed(S/F, ml of solvent to gram of feed) *** process parameters were optimized by statistical approach using historical data design of response surface method(RSM). The oils were characterized for yield, physicochemical properties, dielectric properties and oxidation stability, and comparison was also made with oil extracted using Soxhlet method. Results show that the maximum oil yield of 37% was obtained at 20 min with microwave power intensity of 330 W and S/F ratio of 20. The main fatty acid composition of castor oil is ricinoleic acid. The density, refractive index, dielectric properties and oxidation stability of oils are not affected by the extraction methods and extraction parameters of MAE. However, the MAE-extracted oil is more viscous compared to that by Soxhlet method. With extra caution on oil oxidation, MAE could be a promising solvent extraction method with an 86% less in processing time and a higher yield.

关键词： Castor seed Castor oil Dielectric properties Microwave-assisted solvent extraction Oxidation stability

Transfer Learning-based Computer-aided Diagnosis System for Predicting Grades of Diabetic Retinopathy

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Computers, Materials & Continua 2022年第6期71卷 4573-4590页

作者： Qaisar abbas Mostafa E.A.ibrahim Abdul Rauf Baig College of Computer and Information Sciences Imam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11432Saudi Arabia Department of Electrical Engineering Benha Faculty of EngineeringBenha UniversityQalubiaBenha13518Egypt

Diabetic retinopathy(DR)diagnosis through digital fundus images requires clinical experts to recognize the presence and importance of many intricate *** task is very difficult for ophthalmologists and ***,many computer-aided diagnosis(CAD)systems were developed to automate this screening process *** this paper,aCAD-DR system is proposed based on preprocessing and a pre-train transfer learningbased convolutional neural network(PCNN)to recognize the five stages of DR through retinal fundus *** develop this CAD-DR system,a preprocessing step is performed in a perceptual-oriented color space to enhance the DR-related lesions and then a standard pre-train PCNN model is improved to get high classification *** architecture of the PCNN model is based on three main ***,the training process of the proposed PCNN is accomplished by using the expected gradient length(EGL)to decrease the image labeling efforts during the training of the CNN ***,themost informative patches and images were automatically selected using a few pieces of training labeled ***,the PCNN method generated useful masks for prognostication and identified regions of ***,the DR-related lesions involved in the classification task such as micro-aneurysms,hemorrhages,and exudates were detected and then used for recognition of *** PCNN model is pre-trained using a high-end graphical processor unit(GPU)on the publicly available Kaggle *** obtained results demonstrate that the CAD-DR system outperforms compared to other state-of-the-art in terms of sensitivity(SE),specificity(SP),and accuracy(ACC).On the test set of 30,000 images,the CAD-DR system achieved an average SE of 93.20%,SP of 96.10%,and ACC of 98%.This result indicates that the proposed CAD-DR system is appropriate for the screening of the severity-level of DR.

关键词： Diabetic Retinopathy retinal fundus images computer-aided diagnosis system deep learning transfer learning convolutional neural network

Novel synthesis of stabilized Bi_(1-x-y)Gd_(x)Dy_(y)O_(1.5) solid electrolytes with enhanced conductivity for intermediate temperature solid oxide fuel cells(SOFCs)

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Journal of Rare Earths 2024年第10期42卷 1903-1911页

作者： Ahmed H.ibrahim Yehia M.abbas H.A.Ayoub Marwa H.Ali Mustafa Aldoori Materials Science Laboratory Physics DepartmentFaculty of ScienceSuez Canal University41522IsmailiaEgypt Ministry of Higher Education and Scientific Research Aliraqia University10011BaghdadIraq

Herein,we report the synthesis of a Dy-Gd co-doped cubic phase-stabilized Bi_(2)O_(3) solid electrolyte system via solid-state processing under atmospheric *** with Dy^(3+) and Gd^(3+) has been observed to significantly enhance the densification process during sintering for stabilization purposes,thereby improving the electrical properties of δ-Bi_(2)O_(3)-type *** synthesized ceramics were characterized using X-ray diffraction(XRD),field emission scanning electron microscopy-energy dispersive X-ray spectroscopy(FESEM-EDX),thermal gravimetry/differential thermal analysis(TG/DTA),and the four-point probe technique(4PPT).XRD analysis reveals that the samples Bi_(1-x-y)Gd_(x)Dy_(y)O_(1.5)(y=0.05/x=0.05,0.10,0,15,and 0.20,and x=0.05/y=0.10,0.15,and 0.20) exhibit a stable face-centered cubic δ-phase and a mixed-phase crystallographic *** XRD analysis of the stabilized δ-phase suggests that the prepared oxides show a face-centered cubic(FCC) structure with a space group of *** micrographs reveal that the composition Bi_(0.90)Gd_(0.05)Dy_(0.05)O_(1.5) has no significant ***,an evident increase in the pore formation is observed as the amount of Gd_(2)O_(3) increases until it reaches 20%.This finding suggests that dense pellets are formed during the sintering process at 900-1000℃.The DTA analyses were performed to verify the phase stability,which agrees with the XRD *** electrochemical performance of the synthesized Dy-Gd co-doped Bi_(2)O_(3)solid electrolyte system was evaluated and analyzed in detail by using the electrochemical impedance spectroscopy(EIS) technique,Based on EIS and conductivity measurements,Bi_(0.75)Gd_(0.20)Dy_(0.05)O_(1.5) exhibits the lowest activation energy of 0.519 eV and the highest conductivity value of 0.398 S/cm at 627℃compared to the other samples;this composition can be used as a solid electrolyte for intermediatetemperature solid oxide fuel cells(SOFCs).

关键词： Solid oxide fuel cells(SOFCs) Rare earths Solid-state processing Rietveld Fast Fourier transform(FFT) Electrochemical impedance spectroscopy(EIS)