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Climate change impact and adaptation on wheat yield, water use and water use efficiency at North Nile Delta

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Frontiers of Earth Science 2020年第3期14卷 522-536页

作者： Marwa Gamal mohamed Ali Mahmoud mohamed ibrahim Ahmed el Baroudy Michael Fullen el-Said Hamad Omar Zheli Ding Ahmed Mohammed Saad Kheir Soil and Water Department Faculty of AgricultureTanta UniversityTanta33516Egypt Soils Water and Environment Research InstituteAgricultural Research CenterGiza12411Egypt Faculty of Science and Engineering The University of WolverhamptonWolverhamptonWV11LYUK Haikou Experimental Station Chinese Academy of Tropical Agricultural Sciences(CATAS)Haikou570000China

Investigation of climate change impacts on food security has become a global hot *** so,efforts to mitigate these issues in arid regions have been ***,in this paper,further research is discussed based on data obtained from various crop and climate *** DSSATcrop models(CMs)(CERESWheat and N-Wheat)were calibrated with two wheat cultivars(Gemiza9 and Misr1).A baseline simulation(1981-2010)was compared with different scenarios of simulations using three Global Climate Models(GCMs)for the 2030s,2050s and *** impacts of climate change were assessed using the GCMs and CMs under the high emission Representative Concentration Pathway(RCP8.5).Results predicted decreased wheat grain yields by a mean of 8.7%,11.4%and 13.2%in the 2030s,2050s and 2080s,respectively,relative to the baseline *** impacts of climatic change are probable,despite some uncertainties within the GCMs(i.e.,2.1%,5.0%and 8.0%)and CMs(i.e.,2.2%,6.0%and 9.2%).Changing the planting date with a scenario of plus or minus 5 or 10 days from the common practice was assessed as a potentially effective adaptation option,which may partially offset the negative impacts of climate *** the sowing date by 10 days(from 20 November to 30 November)proved the optimum scenario and decreased further reduction in wheat yields resulting from climate change to 5.2%,6.8%and 8.5%in the 2030s,2050s and 2080s,respectively,compared with the 20 November *** planting 5-days earlier scenario showed a decreased impact on climate change ***,the 10-days early planting scenario increased yield reduction under projected climate *** cultivar Misr1 was more resistant to rising temperature than *** the negative impacts of projected climate change on wheat production,water use efficiency would slightly *** ensemble of multi-model estimated impacts and adaptation uncertainties of climate change can assist decision-makers in planning clima

关键词： DSSAT models scenarios adaptation water use efficiency climate change

The vitreomacular interface in different types of agerelated macular degeneration

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International Journal of Ophthalmology(English edition) 2017年第2期10卷 246-253页

作者： mohamed Abd elM onaem el-Hifnawy Hisham Ali ibrahim Amir Ramadan Gomaa mohamed A elmasry Ophthalmology Department Alexandria University Faculty of MedicineKhartoum SquareAzaritaAlexandria 21526Egypt

AIM： To evaluate the vitreomacular interface in cases with wet age-related macular degeneration（AMD） and to compare them to eyes with dry AMD and normal ***： This was a cross-sectional comparative study that included 87 eyes with wet AMD,42 eyes with dry AMD and 40 eyes without AMD as a control *** coherence tomography（OCT） examination was performed for all patients to assess the vitreomacular ***： In the wet AMD group,34.5% of cases had vitreomacular adhesion（VMA）.Only 14.3% of dry AMD cases and 10% of control cases had *** was a significant difference between the control group and the wet AMD group（P=0.004） as well as the dry and wet AMD group（P=0.017）.There was also a significant difference between the incidence of VMA in patients with subretinal choroidal neovascularization（CNV,type 1） and intraretinal CNV（type 2 or type 3）（P=0.020）.CONCLUSION： There is an association between posterior vitreous attachment and *** is also an increased incidence of VMA with intra-retinal CNV.

关键词： age-related macular degeneration vitreomacular interface optical coherence tomography macula

3D FEM simulations and experimental validation of plastic deformation of pure aluminum deformed by ECAP and combination of ECAP and direct extrusion

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Transactions of Nonferrous Metals Society of China 2017年第6期27卷 1338-1352页

作者： mohamed ibrahim Abd el AAL Mechanical engineering Department College of Engineering Prince Sattam Bin Abdulaziz UniversityWadi Addawasir Kingdom of Saudi Arabia Mechanical Design & Production Department Faculty of Engineering Zagazig University Zagazig Egypt

Rigid-viscoplastic3D finite element simulations(3D FEM)of the equal channel angular pressing(ECAP),thecombination of ECAP+extrusion with different extrusion ratios,and direct extrusion of pure aluminum were performed ***3D FEM simulations were carried out to investigate the load-displacement behavior,the plastic deformationcharacteristics and the effective plastic strain homogeneity of Al-1080deformed by different forming *** simulationresults were validated by microstructure observations,microhardness distribution maps and the correlation between the effectiveplastic strain and the microhardness ***3D FEM simulations were performed successfully with a good agreement with theexperimental *** load-displacement curves and the peak load values of the3D FEM simulations and the experimentalresults were close from each *** microhardness distribution maps were in a good conformity with the effective plastic straincontours and verifying the3D FEM simulations *** ECAP workpiece has a higher degree of deformation homogeneity thanthe other deformation *** microhardness values were calculated based on the average effective plastic *** microhardness values fitted the experimental results *** microstructure observations in the longitudinal andtransverse directions support the3D FEM effective plastic strain and microhardness distributions result in different formingprocesses.

关键词： equal channel angular pressing (ECAP) extrusion finite element method (FEM) microhardness deformation homogeneity microstructure

An Optimized Ensemble Model for Prediction the Bandwidth of Metamaterial Antenna

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Computers, Materials & Continua 2022年第4期71卷 199-213页

作者： Abdelhameed ibrahim Hattan F.Abutarboush Ali Wagdy mohamed Mohamad Fouad el-Sayed M.el-kenawy Computer Engineering and Control Systems Department Faculty of EngineeringMansoura UniversityMansoura35516Egypt electrical Engineering Department College of EngineeringTaibah UniversityMedina42353Saudi Arabia Operations Research Department Faculty of Graduate Studies for Statistical ResearchCairo UniversityGiza12613Egypt Wireless Intelligent Networks Center(WINC) School of Engineering and Applied SciencesNile UniversityGizaEgypt Department of Communications and electronics Delta Higher Institute of Engineering and TechnologyMansoura35111Egypt Faculty of Artificial Intelligence Delta University for Science and TechnologyEgypt

Metamaterial Antenna is a special class of antennas that uses metamaterial to enhance their *** size affects the quality factor and the radiation loss of the *** antennas can overcome the limitation of bandwidth for small *** learning(ML)model is recently applied to predict antenna *** can be used as an alternative approach to the trial-and-error process of finding proper parameters of the simulated *** accuracy of the prediction depends mainly on the selected *** models combine two or more base models to produce a better-enhanced *** this paper,a weighted average ensemble model is proposed to predict the bandwidth of the Metamaterial *** base models are used namely:Multilayer Perceptron(MLP)and Support Vector Machines(SVM).To calculate the weights for each model,an optimization algorithm is used to find the optimal weights of the *** Group-Based Cooperative Optimizer(DGCO)is employed to search for optimal weight for the base *** proposed model is compared with three based models and the average ensemble *** results show that the proposed model is better than other models and can predict antenna bandwidth efficiently.

关键词： Metamaterial antenna machine learning ensemble model multilayer perceptron support vector machines

Assessment of the impact of a 10-MW grid-tied solar system on the Libyan grid in terms of the power-protection system stability

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Clean Energy 2023年第2期7卷 389-407页

作者： Feras Alasali Abdelaziz Salah Saidi Naser el-Naily Othman Alsmadi mohamed Khaleel ibrahim Ghirani Department of electrical Engineering Faculty of EngineeringThe Hashemite UniversityPO Box 330127Zarqa 13133Jordan Department of electrical Engineering King Khalid UniversityAbha PO Box 394Abha City 61411Saudi Arabia Universitéde Tunis el Manar Ecole Nationale d’Ingénieurs de TunisLaboratoire des SystèmesÉlectriquesTunisie electrical Engineering Department College of Electrical and Electronics Technology-BenghaziBenghaziLibya electrical Engineering Department Faculty of EngineeringThe University of JordanAmmanJordan Aeronautical Engineering Department College of Civil Aviation MisrataLibya

The energy market in Libya is expected to face substantial changes in the next few years:electrical energy consumption will increase by 50% within the next 4 ***,there is a plan to gradually increase renewable energy sources in the power network by 2030 to 30%.Solar photovoltaic(PV)plants will play a significant role in the energy transition and the mix of energy sources in *** article is a study conducted to investigate the challenges of power-flow management and power protection from integrating PV power plants into the Libyan power *** particular,a simulation model is built for the Kufra PV power plant(10 MW)with eight buses to assess the power network performance in terms of power quality such as voltage profile,power losses and ***,the impact of the PV plant on the short-circuit level and the power-protection system is presented under different operating *** fault ride-through(FRT)is operated using standard ambient temperature and a wide range of irradiation intensity,and is verified by using the Libyan grid *** results show that the integration of the PV plant into the grid has a significant impact on the short-circuit level and the FRT over the different fault levels and locations on the *** initial period of the three-phase fault shows that the PV plant will be disconnected from the grid due to a decrease in the root mean square value voltages where the reactive and active power of the grid reach 938 MVAR and 261 MW,*** results show that increasing the fault level will lead to an increase in injecting the active *** work is considered the first extensive investigation into the challenges of modern power-flow management and power protection for the power network system in Libya.

关键词： photovoltaic renewable energy sources power protection voltage profile fault ride-through

Intelligent Beetle Antenna Search with Deep Transfer Learning Enabled Medical Image Classification Model

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Computer Systems Science & Engineering 2023年第9期46卷 3159-3174页

作者： mohamed ibrahim Waly Department of Medical Equipment Technology College of Applied Medical SciencesMajmaah UniversityAl Majmaah11952Saudi Arabia

Recently,computer assisted diagnosis(CAD)model creation has become more dependent on medical picture *** is often used to identify several conditions,including brain disorders,diabetic retinopathy,and skin *** traditional CAD methods relied on textures,colours,and *** many models are issue-oriented,they need a more substantial capacity to generalize and cannot capture high-level problem domain *** deep learning(DL)models have been published,providing a practical way to develop models specifically for classifying input medical *** paper offers an intelligent beetle antenna search(IBAS-DTL)method for classifying medical images facilitated by deep transfer *** IBAS-DTL model aims to recognize and classify medical pictures into various *** order to segment medical pictures,the current IBASDTLM model first develops an entropy based weighting and first-order cumulative moment(EWFCM)***,the DenseNet-121 techniquewas used as a module for extracting *** an extreme learning machine(elM)model is used to classify the medical photos.A wide variety of tests were carried out using a benchmark medical imaging dataset to demonstrate the IBAS-DTL model’s noteworthy *** results gained indicated the IBAS-DTL model’s superiority over its pre-existing techniques.

关键词： Medical image segmentation image classification decision making computer aided diagnosis deep learning

Geochemistry of lamprophyres associated with uranium mineralization, Southeastern Desert, Egypt

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Chinese Journal Of Geochemistry 2007年第4期26卷 356-365页

作者： mohamed E. ibrahim mohamed M. el-Tokhi Gehad M. Saleh Mamdouh A. Hassan mohamed A. Rashed Nuclear Materials Authority P. O. Box 530 El Maadi Cairo Egypt Geology Deprtment Faculty of Science United Arab Emirates University United Arab Emirates

Two brecciated shear zones (NNW-SSE) are found crosscutting cataclastic rocks. The cataclastic rocks (3.0 km2) occupy the core of the granitic pluton and enclose a roof pendant of mafic-ultramafic rocks. The NNW-SSE-extending lamprophyre dykes vary in thickness from 0.5 m to 1 m and up to 800 m long, cutting the cataclastic rocks and are composed mainly of plagioclases, amphiboles, relics of pyroxenes and K-feldspar phenocrysts embedded in fine-grained groundmass. They are characterized as being peraluminous, calc-alkaline in composition (chemical trap) and enriched in calcite, sulfide and P2O5. The lamprophyres were affected by hydrothermal alteration (chlorite-carbonate alteration) while the cataclastic rocks were affected by diagenetic alteration (K-feldspar-albite alteration). Uranium mineralization is the product of hydrothermal events and has been investigated by X-ray diffraction (XRD) and environmental scanning electron microscopy (ESEM), involving primary uranium minerals (U3O8) and secondary uranium minerals (uranophane and beta-uranophane, kasolite, torbernite, autonite and meta-autonite) in addition to U- bearing minerals (astrocyanite, betafite and fergusonite). The presence of different mineral parageneses associated with clay minerals indicates that the lamprophyres were subjected to acidic and alkaline mineralizing solutions. Moreover, the U-Zr/U, U-Ce/U values show negative correlations, confirming U-enrichment in both cataclastic rocks and shear zones while the Th-eU/eTh, Th-Zr/Th and Th-Ce/Th values show negative correlations, indicating that the U-bearing solutions are rich in Th in the cataclastic rocks only.

关键词：碎裂岩石剪切区域煌斑岩热液蚀变埃及西南地区沙漠地带

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

Direct Power Control Based on Dead-beat Function and Extended Kalman Filter for PV Systems

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Journal of Modern Power Systems and Clean Energy 2023年第3期11卷 863-872页

作者： Mostafa Ahmed ibrahim Harbi Ralph Kennel mohamed Abdelrahem Chair of High-Power Converter Systems(HLU) Technical University of Munich(TUM)80333 MunichGermany Department of electrical Engineering Faculty of EngineeringAssiut UniversityAssiut 71515Egypt Department of electrical Engineering Faculty of EngineeringMenoufia UniversityShebin El-Koum 32511Egypt IEEE

In this paper,a new proposal for the implementation of the well-known direct power control(DPC)technique in grid-connected photovoltaic(PV)systems is ***,the DPC is executed using a look-up table procedure based on the error between the actual and reference values of the active and reactive ***,the structure of the DPC is simple and results in a fast transient behavior of the inner current loop(injected currents).Therefore,in the current study,the DPC is reformulated using a dead-beat *** this formulation,the reference voltage vector(RVV)is obtained in theα-βreference ***,the switching states for the inverter can be obtained based on the sign of the components of the *** suggested DPC is compared with the conventional one and other switching tables,which are intended for performance ***,an extended Kalman filter(EKF)is utilized to eliminate all grid-voltage ***,the switching frequency of the proposed technique is minimized without any need for weighting factors or cost function *** overall control technique is validated using a hardware-in-the-loop(HIL)experimental set-up and compared with other schemes under different operating conditions.

关键词： Photovoltaic(PV)system direct power control(DPC) sensorless control switching frequency minimization weighting factor