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mineralogy and Geochemistry of Uraniferous Sandstones in Fault Zone,Wadi el Sahu Area,Southwestern Sinai,Egypt:Implications for Provenance,Weathering and Tectonic Setting

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Acta Geologica Sinica(English Edition) 2021年第3期95卷 830-845页

作者： Osama R.SALLAm Hamed ImIRA amira m.el TOHAmY Abd elhadi AABBAS Nuclear materials Authority El-Maadi Cairo P.O.Box:530Egypt

Paleozoic rocks in the Wadi el Sahu area are affected by many major faults in different directions.A reverse fault trending NE-SW is exposed for about 300 m of its length as it cuts through the Abu Hamata and Adedia formations on the south side of Wadi el Sahu.A secondary ascending hydrothermal solution carrying heavy metals and radioactive minerals passed through the fault plain and the surrounding fractures,forming mineralized and radioactive *** mineralized zone thickness ranges from 60 cm to 200 cm along the fault *** rocks were analyzed radiometrically using a portable gamma-ray spectrometer,chemically by employing ICP-ES and ICP-mS,as well as mineralogically by both binocular and Environmental Scanning electron *** content was also determined by fire *** and U contents reached up to 2682 and 1216 ppm,*** investigations indicated the presence of uraninite,torbernite,autunite,sklodowskite,kasolite as uranium minerals,thorite as a thorium mineral,monazite,allanite and xenotime as REE-bearing minerals,zircon and columbite as accessory minerals,gold and nickel as precious and base metals,in addition to cassiterite,chalcopyrite,chalcocite and *** REE and U contents are attributed to the circulation of epigenetic U and REE-bearing hydrothermal solutions along the fault plain and its surrounding *** alteration processes could then be confirmed by the presence of the m-type tetrad effect in the REE-patterns of the ferruginous *** non-chondritic ratio of Nb/Ta,Zr/Hf and Y/Ho in the studied sandstone may be attributed to the tetrad *** Ce and Eu anomaly with unusual REE-patterns was represented by the presence of conjugated m-W tetrad effects,indicating either the dual effect of hydrothermal solutions or groundwater with *** results clarify that the tetrad-effects could be used as evidence for the environment of deposition and as an indication for gold minerali

关键词： uranium gold RREs tetrad effect

Sequence stratigraphic evaluation for the Abu madi Formation,Abu madi/el Qar'a/Khilala gas fields,onshore Nile Delta,Egypt

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Petroleum Research 2023年第4期8卷 514-523页

作者： Farouk I.metwalli Amir Ismail m.S.metwally Ibrahim m.el shafei Geology Department Faculty of ScienceHelwan UniversityCairoEgypt Desert Research Center CairoEgypt Petrobel Oil Company CairoEgypt

The present study aims to integrate a large set of geological and geophysical data into a comprehensive model describing the depositional features of the Abu madi/el Qar'a/Khilala gas *** model is based on the sequence stratigraphic framework of the Abu madi Formation defined using cores,well logs,and time-migrated seismic *** trace attribute sections and relative acoustic impedance sections are also used.A possible depositional pattern for the main Level Ill is established,based on the lithological and petrophysical information derived from the seismic data *** Abu madi For-mation can be regarded as a depositional sequence recording the progressive drowning of the incised *** sequence is bounded at the base by an erosional unconformity,created by a drop in the level of the Late messinian Sea,and at the top by a drowning unconformity related to the Early Pliocene *** bottom of Level II divides the Abu madi sequence into two smaller *** both sequences,gas-bearing traps can be found in the Lowstand Systems Tracts,represented by the fluvial Level Ill and fluvial-deltaic Level Il,respectively.

关键词： Abu madi gas field el Qar'a area Khilala area Sequence stratigraphy analysis Onshore Nile Delta Abu madi Formation

Rooted Tree Optimization for Wind Turbine Optimum Control Based on Energy Storage System

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Computers, materials & Continua 2023年第2期74卷 3977-3996页

作者： Billel meghni Afaf Benamor Oussama Hachana Ahmad Taher Azar amira Boulmaiz Salah Saad el-Sayed m.el-kenawy Nashwa Ahmad Kamal Suliman mohamed Fati Naglaa K.Bahgaat Department of electrical Engineering Badji Mokhtar UniversityLSEM LaboratoryAnnaba23000Algeria Department of electrical Engineering Biskra UniversityLGEB LaboratoryBiskra07000Algeria Department of Drilling and Rig mechanics Ksadi Merbah UniversityOuargla30000Algeria College of Computer and Information Sciences Prince Sultan UniversityRiyadh11586Saudi Arabia Faculty of Computers and Artificial Intelligence Benha UniversityBenha13518Egypt Department of electronics University of Badji MokhtarLERICA LaboratoryAnnaba23000Algeria Delta Higher Institute for Engineering&Technology(DHIET) Mansoura35511Egypt Faculty of Artificial Intelligence Delta University for Science and TechnologyMansoura35712Egypt Faculty of Engineering Cairo UniversityGiza12613Egypt Department of Communications and electronics Engineering Faculty of EngineeringCanadian International College(CIC)ElShiekh ZayedEgypt

The integration of wind turbines(WTs)in variable speed drive systems belongs to the main factors causing lowstability in electrical ***,in order to avoid this issue,WTs hybridization with a storage system is a *** paper investigates WT system operating at variable *** system contains of a permanent magnet synchronous generator(PmSG)supported by a battery storage system(BSS).To enhance the quality of active and reactive power injected into the network,direct power control(DPC)scheme utilizing space-vector modulation(SVm)technique based on proportional-integral(PI)control is ***,to improve the rendition of this method(DPC-SVm-PI),the rooted tree optimization technique(RTO)algorithm-based controller parameter identification is used to achieve PI optimal *** compare the performance ofRTO-based controllers,they were implemented and tested along with some other popular controllers under different working *** obtained results have shown the supremacy of the suggested PIRTO algorithm compared to competing controllers regarding total harmonic distortion(THD),overshoot percentage,settling time,rise time,average active power value,overall efficiency,and active power steadystate error.

关键词： Rooted tree optimization(RTO)method direct power control(DPC) wind turbine(WT) proportional integral(PI) PmSG

Adipose tissue-derived mesenchymal stem cells and chitosan/poly(vinyl alcohol)nanofibrous scaffolds for cartilage tissue engineering

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Cell Regeneration 2020年第1期9卷 62-73页

作者： Ghada Nour-eldeen mazen Abdel-Rasheed amira m.el-Rafei Osama Azmy Gehan T.el-Bassyouni molecular Genetics and Enzymology Department National Research CentreDokkiCairo 12622Egypt Stem Cell Research group Medical Research Centre of ExcellenceNational Research CentreCairo 12622Egypt Reproductive Health Research Department National Research Centre33 El-Buhouth StDokkiCairo 12622Egypt Refractories Ceramics and Building Materials DepartmentNational Research CentreDokkiCairo 12622Egypt

Osteoarthritis(OA)has been defined as a chronic inflammatory joint disease characterized by progressive articular cartilage *** growing interest in regenerative medicine,using cell therapy and tissue engineering,where cellular components in combination with engineered scaffolds and bioactive materials were used to induce functional tissue *** the present study,nanofibrous scaffold based on chitosan(CS)/poly(vinyl alcohol)(PVA)were used to develop biologically functionalized biomaterial to mimic the extracellular matrix,allowing the human adipose tissue derived mesenchymal stem cells(ADSCs)to proliferate and differentiate to chondrogenic *** morphology of the nanofibrous mat was examined using field emission scanning electron microscope(FE/SEm).The characteristic functional groups and the nature of the chemical bonds between atoms were evaluated using Fourier transform infrared spectroscopy(FTIR)*** of the seeded cells was morphologically evaluated by scanning electron microscopy and by flow cytometry for the expression of the stem cell surface *** differentiation potential was verified after chondrogenic induction by analyzing the expression of chondrogenic marker genes using real-time(RT PCR).Current study suggest significant potential for the use of ADSCs with the nanofibrous scaffolds in improving the osteoarthritis pathology.

关键词： Adipose tissue mesenchymal stem cells Nanofibrous scaffolds Osteoarthritis Cartilage tissue engineering

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

Efficient Segmentation Approach for Different medical Image modalities

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Computers, materials & Continua 2022年第11期73卷 3119-3135页

作者： Walid el-Shafai amira A.mahmoud el-Sayed m.el-Rabaie Taha E.Taha Osama F.Zahran Adel S.el-Fishawy Naglaa F.Soliman Amel A.Alhussan Fathi E.Abd el-Samie Department electronics and electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Security Engineering Laboratory Department of Computer SciencePrince Sultan UniversityRiyadh11586Saudi Arabia Department of Information Technology College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadhSaudi Arabia

This paper presents a study of the segmentation of medical *** paper provides a solid introduction to image enhancement along with image segmentation *** the first step,the morphological operations are employed to ensure image detail protection and *** objective of using morphological operations is to remove the defects in the texture of the ***,the Fuzzy C-means(FCm)clustering algorithm is used to modify membership function based only on the spatial neighbors instead of the distance between pixels within local spatial neighbors and cluster *** proposed technique is very simple to implement and significantly fast since it is not necessary to compute the distance between the neighboring pixels and the cluster *** is also efficient when dealing with noisy images because of its ability to efficiently improve the membership partition *** results are performed on different medical image ***(Us),X-ray(mammogram),Computed Tomography(CT),Positron Emission Tomography(PET),and magnetic Resonance(mR)images are the main medical image modalities used in this *** obtained results illustrate that the proposed technique can achieve good results with a short time and efficient image *** results on different image modalities show that the proposed technique can achieve segmentation accuracies of 98.83%,99.71%,99.83%,99.85%,and 99.74%for Us,mammogram,CT,PET,and mRI images,respectively.

关键词： Image segmentation ultrasonic mammogram CT PET mRI morphological operations FCm active contours

Tribological Characterization of Hybrid metal matrix Composites Processed by Powder metallurgy

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Acta metallurgica Sinica(English Letters) 2017年第8期30卷 781-790页

作者： m. megahed m. A. Attia m. Abdelhameed A. G. el-shafei Department of mechanical Design and Production Engineering Faculty of EngineeringZagazig UniversityP.O.Box 44519ZagazigEgypt

Aluminum （Al）-based aluminum oxide （Al2O3） and silicon carbide （SIC） particles hybrid metal matrix com- posites were processed by powder metallurgy technique, followed by sintering at 500 ℃ and then hot extrusion. The tribological properties of these composites with different weight fractions of Al2O3 and SiC were investigated; extrusion process significantly reduces the extent of porosity after cold compaction and sintering processes. Hybridization of the two reinforcements improved hardness and wear resistance of the composites. With an increase in SiC content, hardness was increased and consequently the wear resistance was enhanced also. Scanning electron microscopy observations show a better interfacial bond between matrix and reinforcements and a better distribution of the reinforcements.

关键词： Hybrid metal matrix composite Powder metallurgy Abrasive wear Hardness Porosity

Deep CNN model for multimodal medical Image Denoising

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Computers, materials & Continua 2022年第11期73卷 3795-3814页

作者： Walid el-Shafai amira A.mahmoud Anas m.Ali el-Sayed m.el-Rabaie Taha E.Taha Osama F.Zahran Adel S.el-Fishawy Naglaa F.Soliman Amel A.Alhussan Fathi E.Abd el-Samie Department electronics and electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Security Engineering Laboratory Department of Computer SciencePrince Sultan UniversityRiyadh11586Saudi Arabia Alexandria Higher Institute of Engineering&Technology(AIET) AlexandriaEgypt Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadhSaudi Arabia

In the literature,numerous techniques have been employed to decrease noise in medical image modalities,including X-Ray(XR),Ultrasonic(Us),Computed Tomography(CT),magnetic Resonance Imaging(mRI),and Positron Emission Tomography(PET).These techniques are organized into two main classes:the multiple Image(mI)and the Single Image(SI)*** the mI techniques,images usually obtained for the same area scanned from different points of view are used.A single image is used in the entire procedure in the SI *** denoising techniques can be carried out both in a transform or spatial *** paper is concerned with single-image noise reduction techniques because we deal with single medical *** most well-known spatial domain noise reduction techniques,including Gaussian filter,Kuan filter,Frost filter,Lee filter,Gabor filter,median filter,Homomorphic filter,Speckle reducing anisotropic diffusion(SRAD),Nonlocal-means(NL-means),and Total Variation(TV),are ***,the transform domain noise reduction techniques,including wavelet-based and Curvelet-based techniques,and some hybridization techniques are ***,a deep(Convolutional Neural Network)CNN-based denoising model is proposed to eliminate Gaussian and Speckle noises in different medical image *** model utilizes the Batch Normalization(BN)and the RelU as a basic *** a result,it attained a considerable improvement over the traditional *** previously mentioned techniques are evaluated and compared by calculating qualitative visual inspection and quantitative parameters like Peak Signal-to-Noise Ratio(PSNR),Correlation Coefficient(Cr),and system complexity to determine the optimum denoising algorithm to be applied *** on the quality metrics,it is demonstrated that the proposed deep CNN-based denoising model is efficient and has superior denoising performance over the traditionaldenoising techniques.

关键词： Image enhancement medical imaging speckle noise Gaussian noise denoising filters CNN denoising

Hybrid Segmentation Approach for Different medical Image modalities

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Computers, materials & Continua 2022年第11期73卷 3454-3471页

作者： Walid el-Shafai amira A.mahmoud el-Sayed m.el-Rabaie Taha E.Taha Osama F.Zahran Adel S.el-Fishawy Naglaa F.Soliman Amel A.Alhussan Fathi E.Abd el-Samie Department electronics and electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Security Engineering Laboratory Department of Computer SciencePrince Sultan UniversityRiyadh11586Saudi Arabia Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadhSaudi Arabia

The segmentation process requires separating the image region into sub-regions of similar *** sub-region has a group of pixels having the same characteristics,such as texture or *** paper suggests an efficient hybrid segmentation approach for different medical image modalities based on particle swarm optimization(PSO)and improved fast fuzzy C-means clustering(IFFCm)*** extensive comparative study on different medical images is presented between the proposed approach and other different previous segmentation *** existing medical image segmentation techniques incorporate clustering,thresholding,graph-based,edge-based,active contour,region-based,and watershed *** paper extensively analyzes and summarizes the comparative investigation of these ***,a prediction of the improvement involves the combination of these techniques is *** obtained results demonstrate that the proposed hybrid medical image segmentation approach provides superior outcomes in terms of the examined evaluation metrics compared to the preceding segmentation techniques.

关键词： Image segmentation ultrasonic images X-ray images CT images PET images mR images fuzzy c-mean morphological operations active contour