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Regional Evaluation of GOCE-Based GGMs with Ground-Based Gravity and GPS/Levelling Data over Egypt

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International Journal of Geosciences 2019年第6期10卷 652-668页

作者： Ahmed Saadon Basem elsaka Mohamed el-Ashquer gamal el-Fiky Construction Engineering and Utilities Department Faculty of Engineering Zagazig University Zagazig Egypt National Research Institute of Astronomy and Geophysics (NRIAG) Cairo Egypt Institute of Geodesy and Geoinformation University of Bonn Bonn Germany The Bilbies Higher Institute of Engineering Bilbies Egypt

The gravity field and steady-state ocean circulation explorer (GOCE) sa.ellite mission has provided numerous Global Geopotential Models (GGMs) with different processing methodologies and model accuracies. In the current contribution, the latest releases of GOCE-based GGMs are evaluated on the regional scale using the available terrestrial GPS/Levelling and gravity data collected over Egypt. To overcome the spectral inconsistency between the GOCE-based GGMs and the ground-based data, the spectral enhancement method (SEM) is applied. Five of GOCE-based GGMs have been used, na.ely GOSG01S, IGGT_R1, IfE_GOCE05s_ GO_CONS_GCF_2_SPW_R5 (SPW_R5 in the following) and NULP-02. The evaluation process of GOCE-based GGMs with the available ground data over Egypt considering the SEM method shows remarkable improvements obtained from the SPW_R5 model. The model provides lower differences of the standard deviations with respect to the EGM2008 and the other applied geopotential gravity models as well as the applied ground-based gravity and GPS/Levelling data. The findings regarding the ground-based data show obvious reductions of about 15.16% and 32.22% achieved by the GOCE-based model in term of standard deviations differences of gravity anomalies and geoid heights, respectively. Therefore, the SPW_R5 model is recommended to be applied as a reference model for compensating the long-to-short wa.elength (up to spherical harmonics degree/order 280) components when modelling the gravimetric geoid over Egypt.

关键词： GOCE-Based GGMs Gravity Anomalies GNSS/Levelling Spectral Enhancement Method (SEM)

Springback of I-Section Beam after Pure Bending with von Mises Criteria

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World Journal of Engineering and Technology 2018年第1期6卷 104-118页

作者： Reham Saleh gamal Ali Abla.el-Megharbel Port Said Egypt Department of Production Engineering Port Said University Port Said Egypt

The objective of the present paper is to introduce a theoretical analysis of bending I-sections after pure bending. The springback values are determined to provide a quantitative method for predicting the springback using von Mises criteria. The analytical methods for the I-section are given for two cases according to the positions of the yield point along the height of the beam. The controlling parameters on the springback of I-sections are studied. The results obtained are quite successful for the prediction of springback for bending I-sections.

关键词： Bending Sections Beam Springback von Mises

Change of the mode of failure by interface friction and width-to-height ratio of coal specimens

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Journal of Rock Mechanics and Geotechnical Engineering 2015年第3期7卷 256-265页

作者： gamal Rashed Syd S.Peng Department of Mining Engineering West Virginia University

Bumps in coal mines have been recognized as a major hazard for many years. These sudden and violent failures around mine openings have compromised safety, ventilation and access to mine *** studies showed that the violence of coal specimen failure depends on both the interface friction and width-to-height（W/H） ratio of coal specimen. The mode of failure for a uniaxially loaded coal specimen or a coal pillar is a combination of both shear failure along the interface and compressive failure in the coal. The shear failure along the interface triggered the compressive failure in coal. The compressive failure of a coal specimen or a coal pillar can be controlled by changing its W/H ratio. As the W/H ratio increases, the ultimate strength increases. Hence, with a proper combination of interface friction and the W/H ratio of pillar or coal specimen, the mode of failure will change from sudden violent failure which is brittle failure to non-violent failure which is ductile failure. The main objective of this paper is to determine at what W/H ratio and interface friction the mode of failure changes from violent to non-violent. In this research, coal specimens of W/H ratio ranging from 1 to 10 were uniaxially tested under two interface frictions of 0.1 and 0.25, and the results are presented and discussed.

关键词： Bump Burst Coal strength Violent failure Width-to-height(W/H) ratio Interface friction Stressestrain curve

Ensemble Machine Learning to Enhance Q8 Protein Secondary Structure Prediction

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Computers, Materials & Continua 2022年第11期73卷 3951-3967页

作者： Moheb R.Girgis Rofida M.gamal Enas elgeldawi Computer Science Department Faculty of ScienceMinia University61519MiniaEgypt

Protein structure prediction is one of the most essential objectives practiced by theoretical chemistry and bioinformatics as it is of a vital importance in medicine,biotechnology and *** secondary structure prediction(PSSP)has a significant role in the prediction of protein tertiary structure,as it bridges the gap between the protein primary sequences and tertiary structure *** secondary structures are classified into two categories:3-state category and 8-state *** the 3 states and the 8 states of secondary structures from protein sequences are called the Q3 prediction and the Q8 prediction problems,*** 8 classes of secondary structures reveal more precise structural information for a variety of applications than the 3 classes of secondary structures,however,Q8 prediction has been found to be very challenging,that is why all previous work done in PSSP have focused on Q3 *** this paper,we develop an ensemble Machine Learning(ML)approach for Q8 PSSP to explore the performance of ensemble learning algorithms compared to that of individual ML algorithms in Q8 *** ensemble members considered for constructing the ensemble models are well known classifiers,na.ely SVM(Support Vector Machines),KNN(K-Nearest Neighbor),DT(Decision Tree),RF(Random Forest),and NB(Naïve Bayes),with two feature extraction techniques,na.ely LDA(Linear Discriminate Analysis)and PCA(Principal Component Analysis).Experiments have been conducted for evaluating the performance of single models and ensemble models,with PCA and LDA,in Q8 *** novelty of this paper lies in the introduction of ensemble learning in Q8 PSSP *** experimental results confirmed that ensemble ML models are more accurate than individual ML *** also indicated that features extracted by LDA are more effective than those extracted by PCA.

关键词： Protein secondary structure prediction(PSSP) Q3 prediction Q8 prediction ensemble machine leaning boosting bagging

A silent network’s resounding success:how mutations of core metabolic genes confer antibiotic resistance

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Signal Transduction and Targeted Therapy 2021年第9期6卷 2601-2602页

作者： gamal Wareth Heinrich Neubauer Lisa D.Sprague Friedrich-Loeffler-Institut Institute of Bacterial Infection and ZoonosesJenaGermany Department of Bacteriology Mycology and ImmunologyFaculty of Veterinary MedicineBenha UniversityToukhEgypt

A largely underrated factor in antibiotic resistance is the role of metabolic *** a recent paper published in Science,Lopatkin et al.1 used different in vitro evolution protocols and extensive sequencing data analyses to demonstrate that metabolic mutations develop in response to antibiotic treatment in clinically relevant bacteria(Fig.1).

关键词： resistance network silent

Mitochondrial DNA-Based Identification of Developmental Stages and Empty Puparia of Forensically Important Flies(Diptera)in Egypt

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Journal of Forensic Science and Medicine 2018年第3期4卷 129-134页

作者： Hedayat A.Abdel Ghaffar Marie Z.Moftah Alexandre Favereaux Mohamed Swidan Omar Shalaby Sara.el Ramah Reda gamal Department of Zoology Faculty of ScienceAlexandria University department of Life Science University of Bordeauxinterdisciplinary Institute of Neuroscience UMR 5297CNRSBordeauxFrance department of Biology and Geology Faculty of EducationAlexandria UniversityAlexandriaEgypt department of Life Science Faculty of BiologyTechnische Universitat DresdenDresdenGermany

Relying on morphology in the estimation of postmortem intervals is not always accurate for all life phases of flies,especially for immature *** present study demonstrates the application of cytochrome oxidase I sequences,a partial mitochondrial(mt)gene region,to differentiate forensically important flies in Alexandria,***-three adult flies,larvae,and pupae were collected from rabbit *** were used for *** analysis revealed no significant intraspecific divergence in Diptera ***,a neighbor-coining tree using the Kimura 2-parameter model illustrated reciprocal morphology between *** represented five species,four genera,four subfamilies,two families,and one *** herein identify five different species,Chrysomya albiceps,Chrysomya megacephala,Calliphora vicina,Lucilia sericata,and Ophyra capensis,using mt DNA as a species-specific marker for identification in a local database set-up.

关键词： Cytochrome oxidase Diptera mitochondrial DNA phylogenetic analysis

Investigation of Connecting Wind Turbine to Radial Distribution System on Voltage Stability Using SI Index and λ - V Curves

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Smart Grid and Renewable Energy 2016年第1期7卷 16-45页

作者： gamal Abd el-Azeem Mahmoud Eyad Saeed Solimanx Oda Department of electrical Engineering Faculty of Engineering Suez Canal University Ismailia Egypt

The growth of wind energy penetration level in distribution system raises the concern about its impact on the operation of the power system, especially voltage stability and power loss. Among the major concerns, this paper studied the impact of connecting wind Turbine (WT) in radial distribution system with different penetration levels and different power factor (lead and lag) on power system voltage stability and power loss reduction. Load flow calculation was carried out using forward-backward sweep method. The analysis proceeds on 9- and 33-bus radial distribution systems. Results show that voltage stability enhancement and power loss reduction should be considered as WT installation objective.

关键词： Power Loss Radial Distribution System Si Index Voltage Stability Optimal Size and Location of Wind Turbine

Study on the Mediterranean coastal seaweed Ulva linza exposed to natural and stressed environmental conditions

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Journal of Coastal Life Medicine 2015年第10期 766-775页

作者： Ayman Abd elmoneim el-gamal Eman Mohamed Fakhry Dahlia Mohamed el-Maghraby Department of Marine Geology Coastal ResearchInstituteNational Water Research Center15El-Pharanna StreetEl-Shallalat21514 AlexandriaEgypt Department of Botany and Microbiology Faculty of ScienceAlexandria University21511 AlexandriaEgypt

Objective:To study Ulva linza(***)as macro-alga exposed to different levels of ionizing radiation from the natural background of ***:Samples of *** were collected from two different habitats at the two terminals of the rocky shore of Abu Qir Bay,Alexandria,*** western terminal at Abu Qir represented an area of normal background radiation while the eastern terminal at Rosetta represented an area of relatively high background *** between the algae grown in areas of relatively high and normal background radiation was investigated by using different ***,the ambient water quality was measured and the concentrations of natural radionuclides(^(238)U,^(232)Th and^(40)K)bio-accumulated in the tested macro-alga were ***:The algae naturally exposed to radionuclides(^(238)U series,^(232)Th series and^(40)K)were *** dose rates in *** inhabiting in Rosetta and Abu Qir were calculated as 70.12 and 42.67 nGy/h,*** analysis of algal samples demonstrated that total pigment contents were 2.21 and 2.19 mg/g on a fresh weight basis for *** inhabiting in Rosetta and Abu Qir,*** acid compositions showed comparable profiles for both algal samples with saturated fatty acids as major *** results of protein profiles confirmed slight differential expression in protein ***-related randomly amplified polymorphic DNA provided evidence that both samples were strongly *** using transmission electron microscopy,no obvious ultra structural changes in the examined cells were ***:These experimental results demonstrate that radiation doses are not high enough to cause damage or manifest any significant variation in Ulva tissues.

关键词： Ulva linza Radionuclides Protein profile Random amplified polymorphic DNA electron microscopy

Correlation between SYNTAX Score and Pattern of Risk Factors in Patients Referred for Coronary Angiography in Cardiology Department, Menoufia University

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World Journal of Cardiovascular Diseases 2018年第8期8卷 431-439页

作者： Ahmed Mokhtar el Kersh Ahmed Ashraf Reda Mohamed gamal el Hadad Khaled Hussein el-Sharnouby Department of Cardiology Menoufia University Hospitals Menoufia Egypt Department of Cardiology Shibin El Kom Teaching Hospital Menoufia Egypt

Objectives: The role of SYNTAX (SX) score in assessing the complexity of coronary artery disease (CAD) is well established. In this study we investigate the relationship between conventional risk factors of CAD with its complexity using SX score. Methods: The study consisted of 52 patients with CAD who were admitted to Cardiology Department—Menoufia University Hospitals for elective coronary angiography. The overall SX score was calculated prospectively using the SX score algorithm. Then comparison was done between populations with and without each risk factor. Results: There was a statistically significant correlation between age, hypertension, diabetes mellitus, dyslipidemia and smoking with SX score results (p 0.05). In a multivariate regression analysis, including conventional risk factors of CAD as independent covariates, it revealed that aging, having diabetes mellitus and smoking were identified as significant independent risk factors for CAD complexity. Conclusion: Advanced age, having diabetes mellitus and cigarette smoking are considered to be independent risk factors for the complexity of CAD. Therefore, when these factors present, we expect that the SX score of the patient to be high indicating a complex CAD.

关键词： Coronary Artery Disease SYNTAX Score Risk Factors