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Standard precaution measurements during ophthalmology practice in the pandemic stage of COVID-19

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International Journal of Ophthalmology(English edition) 2020年第7期13卷 1017-1022页

作者： Ahmed mohamed reda Wael m.Ahmed Department of ophthalmology Faculty of MedicineAin Sham UniversityCairo 11566Egypt Dar Eloyoun Eye Laser Centers Muscat 118Oman

AIm:To take specific precautions and keep a safe practice during providing ophthalmology health services without compromising the patient’s safety as well as the team workers and the community in the pandemic stage of corona virus disease 2019(COVID-19).mETHODS:Applying patient circulation scheme implemented in our ophthalmology centers with the guidance of ministry of health infection control guidelines star ted from the moment that we receive a call or Whats App message or Facebook inquiry from patients until 21 d after patients first visit if *** directions were ***,community awareness of the disease and the ophthalmology related advices in how eye can transfers the infection and how to protect our eyes not to be infected through videos interviews of our consultants and distribution in social media like Instagram,Facebook,Whats App pages radio and TV interviews as well as leaflet health awareness for distribution for ***,scheduling of patients’appointments to prevent overcrowdings and cross ***,protective measurements tools in the center to detect and prevent any exposure of the patients to patients and to protect medical staff,COVID-19 scoring system was set up to identify patients with fever,respiratory symptoms,acute conjunctivitis or recent travel to outbreak areas and to encourage these individuals to postpone their appointments for at least 21 *** use of personal protective equipment was *** all the elective surgeries keeping only the emergency types advised by fourth:how to deal with our patients if they need an urgent ophthalmological intervention and how to deal with suspected cases of corona if any cases ***:Our measures helped our colleagues to try to keep providing ophthalmology health services without increasing the incidence of infection for COVID-19 until this pandemic is ***:In our practice,ophthalmologists should work with new aura of social media to facilitate the

关键词： corona virus COVID-19 Instagram Facebook WhatsApp personal protective equipment

Synthesis of glass ceramics from kaolin and dolomite mixture

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International Journal of minerals,metallurgy and materials 2017年第2期24卷 194-201页

作者： mohamed reda Boudchicha Fausto Rubio Slimane Achour Engineering mechanics and materials Laboratory Mechanical Engineering Department Faculty of Technology Universite 20 Aout 1955 de Skikda Skikda 21000 Algeria Ceramics and Glass Institute Consejo Superior de Investigaciones Cientificas Madrid 28049 Spain National Polytechnic School Constantine 25000 Algeria

Cordierite- and anorthite-based binary glass ceramics of the CaO-mgO-Al2O3-SiO2 （CmAS） system were synthesized by mixing local and abundant raw minerals （kaolin and doloma by mass ratio of 82/18）. A kinetics study reveals that the activation energy of crystalli- zation （Ea） calculated by the methods of Kissinger and marotta are 438 kJ·mol^-1 and 459 kJ·mol^-1, respectively. The Avrami parameter （n） is estimated to be approximately equal to 1, corresponding to the surface crystallization mechanism. X-ray diffraction （XRD） analysis shows that the anorthite and cordierite crystals are precipitated from the parent glass as major phases. Anorthite crystals first form at 850℃, whereas the μ-cordierite phase appears after heat treatment at 950℃. Thereafter, the cordierite allotropically transforms to α-cordierite at 1000℃. Complete densification is achieved at 950℃; however, the density slightly decreases at higher temperatures, reaching a stable value of 2.63 kg·m^-3 between 1000℃ and 1100℃, The highest Vickers hardness of 6 GPa is also obtained at 950℃. However, a substantial decrease in hardness is recorded at 1000℃; at higher sintering temperatures, it slightly increases with increasing temperature as the ct-cordierite crystallizes.

关键词： glass ceramics kaolinite dolomite crystallization activation energy

Optimized system for combined production of electricity/green hydrogen for multiple energy pathways:a case study of Egypt

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Clean Energy 2024年第4期8卷 219-236页

作者： reda Ragab mohamed HamdiHafez A.El Salmawy mohamed A.Ismail mechanical Power Engineering Department Zagazig UniversityZagazig 44519Egypt mechanical Engineering Department College of EngineeringKing Faisal UniversityAl-Ahsa 31982Saudi Arabia

By optimal sizing of a wind/photovoltaic hybrid renewable-energy(RE)system,trimming the surplus capacity to reduce the fluctuations in the electricity supplied to the grid,and using it to produce green hydrogen through electrolysis,a stable output with maximum possible capacity factor(CF)is generated to maintain the electricity grid ***,the trimmed energy is used in a secondary conversion path that minimizes the weighted average cost of the energy generated from the entire *** surplus power-to-gas conversion allows the use of green hydrogen to produce electricity,methanol,or ammonia subject to the resource availability,site characteristics,and financial *** on robust site selection criteria,the best performance is obtained at two sites:Ras Ghareb and minya,achieving the lowest energy cost with some variance in their *** the Ras Ghareb site,the optimally sized RE plant provided the grid with a quasi-steady capacity of 423 mW with a CF of 80.04%and was capable of injecting 2965.8648 GWh throughout the year with the lowest cost of 2.4355¢/kWh.A surplus of 3.9%of the total energy produced from the plant was directed to produce 1922-ton H_(2)/year,achieving the lowest cost of hydrogen production of$1.9745/kg H_(2).For the other selected site,minya,the clipped energy is used to produce 3330.47-ton H_(2)/year with an optimized lowest cost of$3.5268/kg H_(2).The difference in hydrogen costs was attributed to the number of full operating hours of the electrolyser in both *** cost is mainly affected by the electricity price and the electrolyser *** both tending to decrease,future forecasts show hydrogen cost reductions.

关键词： hybrid renewable-energy system(HRES) green hydrogen electrolysis power-to-gas methanol ammonia

3D static modeling and sequence stratigraphy using well logs and seismic data:An example of Abu Roash G member in Bahga oilfield

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Energy Geoscience 2024年第3期5卷 362-377页

作者： mohamed reda mohamed Fathy mohamed mosaad Fahad Alshehri mohamed S.Ahmed Geology Department Faculty of ScienceAl-Azhar UniversityP.O.Box 11884Nasr CityCairoEgypt Abdullah Alrushaid Chair for Earth Science Remote Sensing Research Geology and Geophysics DepartmentCollege of ScienceKing Saud UniversityRiyadh11451Saudi Arabia

This research uses both three-dimensional(3D)modeling and geologic well control to piece back together the architectural parts of the Late Cretaceous *** goal is to figure out the sizes,directions,locations,and controls of the layers of the fluvial sandstone *** stratigraphy is essential for 3D reservoir modeling and petroleum geology understanding in the Bahga *** purpose of this work is to create a static model that shows the layers and facies distribution in the reservoir *** will use data from nine well logs and 22 seismic lines calibrated by the Abu Roash G member reservoir core intervals to accomplish *** petrophysical study discovered three parts in the Abu Roash G member reservoir rock:channel fill that is affected by tides,channel fill that is dominated by tides(intertidal sands),and channel top with lenticular bedded *** model's findings point to the existence of an NNW-oriented sand body,which could be a prime location to produce *** original oil in place(OOIP)is about 3,438,279 Stock Tank Barrels(STB),and the oil reserve reaches up to 1,031,484(STB).Sequence stratigraphic analysis using seismic and well log information(SB)reveals that the Upper Cretaceous AR/G reservoir of the Bahga field is characterized by third-and fourth-order stratigraphic sequences,which are constrained by three maximum Flooding Surfaces(mFS)and two Sequence *** integration of the derived geological model and sequence stratigraphic results can lower future extraction risk by identifying the locations and trends of the geologic facies with the necessary petrophysical properties for the hydrocarbon accumulations.

关键词： Three-dimensional reservoir modeling Sequence stratigraphy Reservoir characterization Abu Roash reservoir Abu Gharadig Basin

Thermal performance of domed roof in air-conditioned spaces

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Energy and Built Environment 2024年第2期5卷 270-287页

作者： Ibrahim reda Raouf N.Abdelmessih mohamed Steit Ehab m.mina mechanical Power Engineering Faculty of EngineeringAin Shams University1 El-Sarayat St.Cairo 11517Egypt Architectural Engineering Faculty of EngineeringAin Shams UniversityCairoEgypt

Due to their thermal performance,domed roofs are one of the passive solutions that affect energy consumption in *** thermal performance of domed roofs has been investigated in many naturally ventilated ***,few studies have discussed their performance in conditioned ***,this study introduces a computational comparison between domed and flat roofs to investigate their impact on thermal comfort inside a conditioned *** an earlier stage,field measurements were carried out inside a Bahraini mosque to acquire its indoor air conditions during the summer period of 2021,in addition to validating the computational *** findings of this study confirm that,under mechanical cooling conditions,the flat roof offers a lower indoor temperature than the domed roof by 0.4℃and 0.1℃for open and closed doors,***,the air velocity is lower by approximately 0.01 m/s for both door *** overall PmV values of the flat roof are also lower by 0.07 and 0.01,while the PPD values are lower by 0.20,and 0.34 for open and closed doors,*** on these small differences,it can be concluded that the thermal performance of both roofing systems behaves equally in conditioned ***,the air patterns are substantially different,the overall thermal performance is *** similarity drives building designers to rethink the thermal performance of the domed roofs in air-conditioned spaces with such a hot climate,regardless of their aesthetic and acoustical behaviour.

关键词： Thermal comfort Computational fluid dynamics(CFD) Predicted mean vote(PmV)and predicted percentage dissatisfied(PPD) Domed roof Flat roof

medical Feature Selection Approach Based on Generalized Normal Distribution Algorithm

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Computers, materials & Continua 2021年第12期69卷 2883-2901页

作者： mohamed Abdel-Basset reda mohamed Ripon K.Chakrabortty michael J.Ryan Yunyoung Nam mohamed Abouhawwash Faculty of Computers and Informatics Zagazig UniversityZagazig44519Egypt Capability Systems Centre School of Engineering and ITUNSWCanberraAustralia Department of Computer Science and Engineering Soonchunhyang UniversityAsan31538Korea Department of mathematics Faculty of ScienceMansoura UniversityMansoura35516Egypt Department of Computational mathematics Scienceand Engineering(CMSE)Michigan State UniversityEast Lansing48824MIUSA

This paper proposes a new pre-processing technique to separate the most effective features from those that might deteriorate the performance of the machine learning classifiers in terms of computational costs and classification accuracy because of their irrelevance,redundancy,or less information;this pre-processing process is often known as feature *** technique is based on adopting a new optimization algorithm known as generalized normal distribution optimization(GNDO)supported by the conversion of the normal distribution to a binary one using the arctangent transfer function to convert the continuous values into binary ***,a novel restarting strategy(RS)is proposed to preserve the diversity among the solutions within the population by identifying the solutions that exceed a specific distance from the best-so-far and replace them with the others created using an effective updating *** strategy is integrated with GNDO to propose another binary variant having a high ability to preserve the diversity of the solutions for avoiding becoming stuck in local minima and accelerating convergence,namely improved GNDO(IGNDO).The proposed GNDO and IGNDO algorithms are extensively compared with seven state-of-the-art algorithms to verify their performance on thirteen medical instances taken from the UCI *** is shown to be superior in terms of fitness value and classification accuracy and competitive with the others in terms of the selected *** the principal goal in solving the FS problem is to find the appropriate subset of features that maximize classification accuracy,IGNDO is considered the best.

关键词： Generalized normal distribution optimization feature selection transfer function novel restarting strategy UCI repository

An Improved Jellyfish Algorithm for multilevel Thresholding of magnetic Resonance Brain Image Segmentations

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Computers, materials & Continua 2021年第9期68卷 2961-2977页

作者： mohamed Abdel-Basset reda mohamed mohamed Abouhawwash Ripon K.Chakrabortty michael J.Ryan Yunyoung Nam Faculty of Computers and Informatics Zagazig UniversityZagazig44519Egypt Department of mathematics Faculty of ScienceMansoura UniversityMansoura35516Egypt Department of Computational mathematics Scienceand Engineering(CMSE)Michigan State UniversityEast LansingMI48824USA Capability Systems Centre School of Engineering and ITUNSW CanberraAustralia Department of Computer Science and Engineering Soonchunhyang UniversityAsan31538Korea

Image segmentation is vital when analyzing medical images,especially magnetic resonance(mR)images of the ***,several image segmentation techniques based on multilevel thresholding have been proposed for medical image segmentation;however,the algorithms become trapped in local minima and have low convergence speeds,particularly as the number of threshold levels ***,in this paper,we develop a new multilevel thresholding image segmentation technique based on the jellyfish search algorithm(JSA)(an optimizer).We modify the JSA to prevent descents into local minima,and we accelerate convergence toward optimal *** improvement is achieved by applying two novel strategies:Rankingbased updating and an adaptive ***-based updating is used to replace undesirable solutions with other solutions generated by a novel updating scheme that improves the qualities of the removed *** develop a new adaptive strategy to exploit the ability of the JSA to find a best-so-far solution;we allow a small amount of exploration to avoid descents into local *** two strategies are integrated with the JSA to produce an improved JSA(IJSA)that optimally thresholds brain mR *** compare the performances of the IJSA and JSA,seven brain mR images were segmented at threshold levels of 3,4,5,6,7,8,10,15,20,25,and *** was compared with several other recent image segmentation algorithms,including the improved and standard marine predator algorithms,the modified salp and standard salp swarm algorithms,the equilibrium optimizer,and the standard JSA in terms of fitness,the Structured Similarity Index metric(SSIm),the peak signal-to-noise ratio(PSNR),the standard deviation(SD),and the Features Similarity Index metric(FSIm).The experimental outcomes and the Wilcoxon rank-sum test demonstrate the superiority of the proposed algorithm in terms of the FSIm,the PSNR,the objective values,and the SD;in terms of the SSIm,IJSA was competitive with

关键词： magnetic resonance imaging brain image segmentation artificial jellyfish search algorithm ranking method local minima Otsu method

maize response to elevated plant density combined with lowered N-fertilizer rate is genotype-dependent

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The Crop Journal 2015年第2期3卷 96-109页

作者： Ahmed medhat m.Al-Naggar reda A.Shabana mohamed m.m.Atta Tarek H.Al-Khalil Agronomy Department Faculty of Agriculture Cairo University

Increasing plant density and improving N fertilizer rate along with the use of high density-tolerant genotypes would lead to maximizing maize(Zea mays L.) grain productivity per unit land area. The objective of this investigation was to match the functions of optimum plant density and adequate nitrogen fertilizer application to produce the highest possible yields per unit area with the greatest maize genotype efficiency. Six maize inbred lines differing in tolerance to low N and high density(D) [three tolerant(T); L-17, L-18, L-53,and three sensitive(S); L-29, L-54, L-55] were chosen for diallel crosses. Parents and crosses were evaluated in the 2012 and 2013 seasons under three plant densities: low(47,600),medium(71,400), and high(95,200) plants ha-1and three N fertilization rates: low(no N addition), medium(285 kg N ha-1) and high(570 kg N ha-1). The T × T crosses were superior to the S × S and T × S crosses under the low N–high D environment in most studied traits across seasons. The relationships between the nine environments and grain yield per hectare(GYPH) showed near-linear regression functions for inbreds L54, L29, and L55 and hybrids L18 × L53 and L18 × L55 with the highest GYPH at a density of47,600 plants ha-1and N rate of 570 kg N ha-1and a curvilinear relationship for inbreds L17, L18, and L53 and the rest of the hybrids with the highest GYPH at a density of95,200 plants ha-1combined with an N rate of 570 kg N ha-1. Cross L17 × L54 gave the highest grain yield in this study under both high N–high-D(19.9 t ha-1) and medium N–high-D environments(17.6 t ha-1).

关键词： Quadratic regression Appropriate N rate High-density tolerant maize Unit area productivity

Oil-source correlation and Paleozoic source rock analysis in the Siwa Basin,Western Desert:Insights from well-logs,Rock-Eval pyrolysis,and biomarker data

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Energy Geoscience 2024年第3期5卷 313-327页

作者： mohamed I.Abdel-Fattah mohamed reda mohamed Fathy Diaa A.Saadawi Fahad Alshehri mohamed S.Ahmed Petroleum Geosciences and Remote Sensing Program Department of Applied Physics and AstronomyCollege of SciencesUniversity of SharjahSharjah27272United Arab Emirates Geology Department Faculty of ScienceSuez Canal UniversityIsmailiaEgypt Faculty of Science Geology DepartmentAl-Azhar UniversityP.O.Box 11884Nasr CityCairoEgypt Abdullah Alrushaid Chair for Earth Science Remote Sensing Research Geology and Geophysics DepartmentCollege of ScienceKing Saud UniversityRiyadh11451Saudi Arabia

Understanding the origins of potential source rocks and unraveling the intricate connections between reservoir oils and their source formations in the Siwa Basin(Western Desert,Egypt)necessitate a thorough oil-source correlation *** objective is achieved through a meticulous analysis of well-log responses,Rock-Eval pyrolysis,and biomarker *** analysis of Total Organic Carbon across 31 samples representing Paleozoic formations in the Siwa A-1X well reveals a spectrum of organic richness ranging from 0.17 wt%to 2.04 wt%,thereby highlighting diverse levels of organic content and the presence of both Type II and Type III *** of the fingerprint characteristics of eight samples from the well suggests that the Dhiffah Formation comprises a blend of terrestrial and marine organic ***,a significant contribution from more oxidized residual organic matter and gas-prone Type III kerogen is ***,the Desouky and Zeitoun formations exhibit mixed organic matter indicative of a transitional environment,and thus featuring a pronounced marine influence within a more reducing setting,which is associated with Type II *** analysis of five oil samples from different wells—SIWA L-1X,SIWA R-3X,SIWA D-1X,PTAH 5X,and PTAH 6X,it is evident that terrestrial organic matter,augmented by considerable marine input,was deposited in an oxidizing environment,and contains Type III *** scrutiny confirms the coexistence of mixed terrestrial organic matter within varying redox *** is the uniformity of identified kerogen Types II and III across all samples,known to have potential for hydrocarbon *** discovery presented in this paper unveils captivating prospects concerning the genesis of oil in the Jurassic Safa reservoir,suggesting potential links to Paleozoic sources or even originating from the Safa member *** revelations mark a substantial advancement in understanding source

关键词： Biomarker data Oil-source correlation Rock-Eval pyrolysis Source rocks Siwa Basin