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Geoscience Frontiers 2013年第4期4卷 469-476页

作者： mohamed metwaly Fouzan AlFouzan King Saud University.College of Science.Geology and Geophysics Department.P.O.Box 2455.Riyadh 11451.Saudi Arabia National Research Institute of Astronomy and Geophysics(NRIAG).Egypt King Abdulaziz City for Science and Technology(KACST).Saudi Arabia

The presence of natural voids and cavities in subsurface karstic limestones causes severe problem for civil engineering and environmental management. The presence of such features hinders the extension of urbanizations particularly in the new metropolitan. The eastern part of Saudi Arabia contains various types of karstic limestone, sinkholes, solution cavities and voids. In this context, geophysical methods particularly electrical resistivity technique is used as a cost-effective solution for investigating subsurface caves, voids, and shallow weathered zones. 2-D electrical resistivity data sets have been acquired along seven profiles in the new urbanization at AI Hassa area. Data processing has been carried out taking into consideration the response of synthetic models, which simulates physical models of the most common karstic features in the area. The results are very useful to determine the extension of shallow weathered zones and to locate different cavities underneath them. The hard limestone bedrock can also be detected and traced along the surveyed profiles.

关键词： Cavity detectionElectrical resistivity tomographySynthetic modeling

The Pan-African Ophiolites and Related Mineralization in Egypt

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Acta Geologica Sinica(English Edition) 2015年第A2期89卷 65-68页

作者： mohamed metwaly Abu Anbar Geology Department Faculty of ScienceTanta University

Precambrian ophiolites are abundant in the Arabian- Nubian Shield of NE Africa and Arabia and range in age fronl 690 to 890 Ma. In Egypt, they are widely distributed in the central and southern Eastern Desert and occu... 详细信息

关键词： RESEARCH Ultrabasic rocks Mafic rocks Igneous rocks Ophiolites Mineralization (Geology)

Compositional Variations and Tectonic Settings of Podiform Chromitites Associated with Ultramafic Rocks of the Pan-African Proterozoic Ophiolites from South Eastern Desert, Egypt

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Acta Geologica Sinica(English Edition) 2020年第S1期94卷 40-42页

作者： mohamed metwaly ABU ANBAR Fernando GERVILLA Geology Department Faculty of ScienceTanta UniversityTantaEgypt Departamento de Mineralogı´a y Petrologı´a Universidad de Granada-CSICAvda.Fuentenueva s/n18002 GranadaSpain

The Precambrian podiform chromitites associated with ophiolites are abundant in Pan-African belt in central Eastern Desert(CED)and south Eastern Desert(SED),Egypt and range from 690 to 890 Ma in *** studied chromitites associated with Neoproterozoic ophiolites are distributed in southern Eastern Desert,Egypt in Baranis-Shalaten sheet and occur as lenticular bodies with variable dimensions in ultramafic component(serpentinites).We present geochemical and mineralogical data from three areas of ophiolites and associated chromitites namely Gebel Abu Dahr(D),Gebel Arais(A)and Gebel Anbat in the Wadi Hodein area(H)(Fig.1).The paper studies the compositional variations and tectonic settings of podiform chromitites associated with ultramafic rocks,in addition to the alteration process of chromite during *** ophiolite in the present areas is composed of the ultramafic rocks(mainly serpentinites)with minor relics of fresh dunite and *** these rocks are affected by metamorphism and subsequent retrograde during subduction and *** samples selected from the serpentinites geochemically analyzed for major,trace and some REE elements and the geochemical results reflect that harzburgite and dunite compositions are typical of depleted mantle *** analyses and SIMS investigations were carried out for three massive podiform chromitite ore bodies and disseminated chromites in serpentinites(1215 spot probe analyses),and silicate minerals in serpentinite rocks such as serpentine and olivine(102 spots).Serpentine minerals are mainly antigorite with some chrysotile in serpentinite rocks and in chromitites,mainly filling cross-cutting *** this study,we consider that the alteration occurred in two stages:during the first one chromite reacted with olivine and water to form Cr-and Fe-rich,porous chromite and chlorite;during the second event magnetite filled the pores,created in the porous chromite and defused into this chromite to for

关键词： Os-rich Laurie Pan-African podiform chromitites Abu Dahl Arayes G.Anbat Holden South Eastern Desert

The Chromitites Associated with the Pan-African Ophiolites in Egypt

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Acta Geologica Sinica(English Edition) 2016年第S1期90卷 206-208页

作者： mohamed metwaly ABU ANBAR Geology Department Faculty of Science Tanta University

Ophiolites components occur in Pan-African belt in Central Eastern Desert(CED)and South Eastern Desert(*** ultramafic components are severely serpentinized and in some areas occur as small fresh

关键词： SED CED The Chromitites Associated with the Pan-African Ophiolites in Egypt Cr rock high

Origin of Some Neo-Proterozoic Ophiolites from Eastern Desert of Egypt:Geochemical Constraints

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Acta Geologica Sinica(English Edition) 2017年第S1期91卷 4-6页

作者： mohamed metwaly ABU ANBAR YANG Jingsui Geology Department Faculty of ScienceTanta University Institute of Geology Chinese Academy of Geological Sciences

The Neo-Proterozoic ophiolites occur in the central and southern Eastern Desert along suture zone as dismemberedmassesinvolcano-sedimentary *** ophiolite component includes ultramafic rocks mainly serpentinites,mafic rocks,minor bodies of trondhjemite,sheeted dykes,metabasalts,and pillow *** Present studies include two ophiolites in Central and southern eastern Desert named Mubarak–El Mayet and Ghadir respectively(Fig.1).The first one named after wadi Mubarak and wadi El Mayet area(55 km north Marsa Alam city)and the second named after Wadi Ghadir(30 km south Marsa Alam city).The dismembered ophiolite components in MubarakEl Mayet mainly composed mainly of serpentinites,ophiolitic metagabbros,sheeted dykes and Pillow *** components occur as thrusted blocks and sheets in metavolcano-sedimentary assemblages(matrix).Gabbros sometimes occur as coarse grained gabbros(appenites)whereas pillows range in size from 30 cm to 1 m(Fig.2a).The second ophiolite sequence expose in Wadi Ghadir and its *** consists of serpentinized peridotites,layered gabbro,massive isotropic gabbro,1fine grained gabbro,sheeted diabase dykes,pillowed basaltic lavas and minor *** serpentinizedperidotites,metapyroxenitesand serpentinites occur as allochthonous dismembered blocks,fragments and sheets in highly sheered metasediments and metavolcanics(mélange)(Fig.2b,c).The massive and layered gabbros occur in the main wadi(Fig.2d,f)and in many places contain some veins and pockets from *** present gabbros intruded by syenogranites from the *** lavas occur between metasedimentary mélange and ophiolitic gabbros in wadi El Beda as tributary of Wadi Ghadir and sometimes occur as fragments in mé*** pillows range in size from 40 cm to 1 m(Fig.2f)and are mainly amygdaloidal and porphyritic basalt and *** dykes cut the gabbros and pillow lavas in the Wadi El Beda and composed mainly from diabase(Fig.2g,h).In the present stu

关键词： Origin of Some Neo-Proterozoic Ophiolites from Eastern Desert of Egypt:Geochemical Constraints

Evaluating some factors that affect feasility of using ground penetrating radar for landmine detection

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Applied Geophysics 2007年第3期4卷 221-230页

作者： mohamed metwaly Ahmed Ismail Jun Matsushima National Research Institute of Astronomy and Geophysics 11421-Helwan Cairo Egypt Geosystem Department Graduate School of Engineering The University of Tokyo 113-8656 Tokyo Japan

Ground penetrating radar （GPR） is one of the promising technologies that can be used to detect landmines. Many factors may affect the ability of GPR to detect landmines. Among those factors are： 1） the type of landmine material （metallic or plastic）, 2） conditions of the host soil （soil texture and soil moisture）, and 3） the radar frequency utilized. The impact of these factors on the ability of GPR to detect landmines is investigated by studying their effect on the dielectric permittivity contrast between the landmine and the host soil, as well as on the attenuation of the radar waves. The impact of each factor was theoretically reviewed and modeled using the Matlab and Mathcad software packages. Results of the computer modeling were correlated with GPR data acquired for metallic and plastic landmine types. It was found that the ability of GPR to detect landmines depends to a great extent on the landmine type, water content of the host soil, utilized radar frequency, and soil texture. The landmines are much easier to detect than plastic landmines for any soil conditions and any radar frequency. Increasing the soil＇s moisture content, regardless of soil texture, eases the detection of the plastic landmine and worsens the detection of the metallic mines. Increasing the percentage of clay in the soil causes the same effect as the moisture content. However, higher radar frequency delivers better results for landmine detection as long as the percentage of clay and the moisture content in the soil remains low. The results of this study are expected to help in selecting optimum radar antennae and data acquisition parameters depending on the landmine type and environmental conditions.

关键词： landmine dielectric permittivity GPR

Groundwater uptake of different surface cover and its consequences in great Hungarian plain

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Ecological Processes 2017年第1期6卷 408-416页

作者： Zoltán Gribovszki Péter Kalicz Kitti Balog András Szabó Tibor Tóth Péter Csáfordi mohamed metwaly Sándor Szalai Institute of Geomatics and Civil Engineering University of SopronSopronHungary Institute for Soil Sciences and Agricultural Chemistry Centre for Agricultural ResearchHungarian Academy of SciencesBudapestHungary Forest Research Institute National Agricultural Research and Innovation CentreBudapestHungary Archaeology Department College of Tourism and ArchaeologyKing Saud UniversityRiyadhSaudi Arabia National Research Institute of Astronomy and Geophysics(NRIAG) CairoEgypt MTA CSFK GGI SopronHungary

Introduction:Forest cover in Hungary has increased from 1.1 to 2.0 million hectares during the last *** EU(European Union)promotes further afforestation;thus,15,000–18,000 ha are being forested each year,mainly in the Hungarian Great *** terms of species used for afforestation,poplar plantations are preferred over native oak *** groundwater uptake of trees can be a significant water balance element of forested areas in shallow groundwater environments within the Hungarian Great *** can cause water table depressions and subsurface salt accumulation in areas with negative water *** study examined the hydrological impact of forest cover in the Hungarian Great *** the framework of this research,climatic water balance,water table depth and salinity,subsoil layering,tree species and stand age were analysed as influencing *** paper compares the effect which an oak forest,a poplar plantation and a pasture have on groundwater uptake and salt ***:The water table level was roughly 0.4–0.5 m lower beneath the oak forest and the poplar plantation than it was beneath the *** groundwater use was 1.5–2 times higher than that of *** uptake of oak forest was greater than that of poplar plantation during the monitoring *** accumulation,which shows water use in the longer run,was slightly higher for poplar in deeper ***:The greater amount of groundwater used by trees does not lead to a higher salt uptake as only a slight accumulation of salt was measured beneath the ***,hybrid poplar was slightly less favourable than native oak when considering salinization ***,even greater groundwater uptake by trees over longer timescales could cause more significant salt accumulation under pronounced drought conditions due to climate change.

关键词： Groundwater recharge/water budget Evapotranspiration Diurnal fluctuation Forest cover Salinization

Volatile organic compounds for the detection of hepatocellular carcinoma—A scoping review

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iLIVER 2024年第1期3卷 45-51页

作者： Sayed metwaly Alicja Psica Opeyemi Sogaolu Irfan Ahmed Ashis Mukhopadhya Mirela Delibegovic mohamed Bekheit Division of Internal Medicine Aberdeen Royal InfirmaryNHS GrampianScotlandAberdeenAB252ZDUnited Kingdom Aberdeen Cardiovascular and Diabetes Centre School of MedicineMedical Sciences and NutritionUniversity of AberdeenForesterhill Health CampusAberdeenAB252ZDUnited Kingdom Department of Critical Care Medicine University of CalgaryAlberta T2N 2T9Canada Department of General Surgery Aberdeen Royal InfirmaryNHS GrampianScotlandAberdeen AB252ZDUnited Kingdom Pakistan Kidney and Liver Institute and Research Centre Lahore 54000Pakistan Hépatica Centre of Integrated HPB CareElite HospitalAlexandria 21325Egypt

Hepatocellular carcinoma(HCC)is an increasingly common and the second leading cause of cancer mortality worldwide with a 5-year survival rate about 12%.Less than 20%of HCC patients are eligible to curative treatment owing to the late ***,there is a need for a readily accessible,early screening *** scoping review critically appraises and synthesizes the current published knowledge about the use of exhaled volatile organic compounds(VOCs)as a potential noninvasive means for HCC detection aiming to advance this nascent field.A systematic electronic search was *** search strategy included all studies published until the 24th of March 2023 using a combination of relevant *** search yielded 9 publications using the Preferred Reporting Items for Systematic Reviews and Meta-analyses *** of the studies described in vitro experiments,and seven clinical studies were conducted on small groups of ***,42 headspace gases were analyzed in the in vitro ***,the clinical studies included 420 HCC patients and 630 *** studies reported potential role for a combination of VOCs in the diagnosis of ***,there is lack of *** there appears to be promise in VOCs research associated with HCC,there is no single volatile biomarker in exhaled breath attributed to HCC and data from extracted studies indicates a lack of *** multicentre population studies are required to verify the existence of VOCs linked to HCC.

关键词： Hepatocellular carcinoma Volatile organic compounds Metabolomics

A New Speed Limit Recognition Methodology Based on Ensemble Learning:Hardware Validation

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Computers, Materials & Continua 2024年第7期80卷 119-138页

作者： mohamed Karray Nesrine Triki mohamed Ksantini ESME ESME Research LabIvry Sur Seine94200France CEM Lab ENISUniversity of SfaxSfax3038Tunisia

Advanced DriverAssistance Systems(ADAS)technologies can assist drivers or be part of automatic driving systems to support the driving process and improve the level of safety and comfort on the *** Sign Recognition System(TSRS)is one of themost important components *** the challengeswith TSRS is being able to recognize road signs with the highest accuracy and the shortest processing ***,this paper introduces a new real time methodology recognizing Speed Limit Signs based on a trio of developed ***,the Speed Limit Detection(SLD)module uses the Haar Cascade technique to generate a new SL detector in order to localize SL signs within captured ***,the Speed Limit Classification(SLC)module,featuring machine learning classifiers alongside a newly developed model called DeepSL,harnesses the power of a CNN architecture to extract intricate features from speed limit sign images,ensuring efficient and precise *** addition,a new Speed Limit Classifiers Fusion(SLCF)module has been developed by combining trained ML classifiers and the DeepSL model by using the Dempster-Shafer theory of belief functions and ensemble learning’s voting *** rigorous software and hardware validation processes,the proposedmethodology has achieved highly significant F1 scores of 99.98%and 99.96%for DS theory and the votingmethod,***,a prototype encompassing all components demonstrates outstanding reliability and efficacy,with processing times of 150 ms for the Raspberry Pi board and 81.5 ms for the Nano Jetson board,marking a significant advancement in TSRS technology.

关键词： Driving automation advanced driver assistance systems(ADAS) traffic sign recognition(TSR) artificial intelligence ensemble learning belief functions voting method

A Distributionally Robust Optimization Scheduling Model for Regional Integrated Energy Systems Considering Hot Dry Rock Co-Generation

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1387-1404页

作者： Hao Qi mohamed Sharaf Andres Annuk Adrian Ilinca mohamed A.mohamed College of Electrical and New Energy China Three Gorges UniversityYichang443002China Department of Industrial Engineering College of EngineeringKing Saud UniversityRiyadh11421Saudi Arabia Institute of Forestry and Engineering Estonian University of Life SciencesTartu51006Estonia Department of Mechanical Engineering école de Technologie SupérieureMontréalQC H3C 1K3Canada Electrical Engineering Department Faculty of EngineeringMinia UniversityMinia61519Egypt

Hot dry rock(HDR)is rich in reserve,widely distributed,green,low-carbon,and has broad development potential and *** this paper,a distributionally robust optimization(DRO)scheduling model for a regionally integrated energy system(RIES)considering HDR co-generation is ***,the HDR-enhanced geothermal system(HDR-EGS)is introduced into the ***-EGS realizes the thermoelectric decoupling of combined heat and power(CHP)through coordinated operation with the regional power grid and the regional heat grid,which enhances the system wind power(WP)feed-in ***,peak-hour loads are shifted using price demand response guidance in the context of time-of-day ***,the optimization objective is established to minimize the total cost in the RIES scheduling cycle and construct a DRO scheduling model for RIES with *** simulating a real small-scale RIES,the results show that HDR-EGS can effectively promote WP consumption and reduce the operating cost of the system.

关键词： Energy harvesting integrated energy systems optimum scheduling time-of-use pricing demand response geothermal energy