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Neoproterozoic Tectonic Events of Egypt

Acta Geologica Sinica(English Edition) 2021年第4期95卷 1366-1405页

作者： mohamed abd EL-WAHED Zakaria HAMIMI Geology Department Faculty of ScienceTanta UniversityTanta 31527Egypt Department of Geology Faulty of ScienceBen ha UniversityBenha 13518Egypt

The Egyptian Nubian Shield(ENS)represents the northwestern part of the Arabian-Nubian Shield and the northern extension of the East African *** ENS is regarded as being formed due to northward-directed escape *** is characterized by mild accretion and suture zones dominated by major strike-slip zones with a commonly sinistral sense of movement;some shear zones display a dextral sense of *** is dominated by gneisses and migmatites in the south,arc volcaniclastic metasediments and highly dismembered ophiolites in the central parts,whereas its northern part is dominated by late-to post-tectonic *** southern Sinai,the Neoproterozoic rocks are grouped into four complexes,namely Feiran–Solaf,Sa’al–Zaghra,Kid and *** ENS ophiolites were formed between 730–750 Ma,mainly in a supra-subduction zone *** ENS has undergone a Neoproterozoic deformation history involving three successive phases:(1)Early N–S shortening phase(D1),(2)Syn-accretionary phase(D2)and(3)Post-accretionary phase(D3).The initial island-arc stage(780–730 Ma)is a N–S shortening phase initiated by collision between the Eastern Desert tectonic terrane to the north with both the Gebeit and Gabgaba terranes to the south(830–720 Ma).During the arc-splitting and back-arc spreading stage(730–620),voluminous syn-tectonic granitoids intruded into the ENS(750–610 Ma).The E–W-directed compressional/transpressional phase(620–450 Ma)led to the overall uplift of the central part of the ENS and consequently the development and exhumation of the core complexes in oblique convergent *** E–W intense shortening deformation resulted also in the formation of NW-and NE-striking sinistral and dextral strike-slip shear zones,*** latest periods of the E–W-directed compressional/transpressional regime were characterized by deposition of the molasse-type Hammamat Sediments unconformably over the Dokhan Volcanics,or interbedded with *** combined thrusting,folding and sin

关键词： Neoproterozoic deformation N–S shortening syn-accretionary phase post-accretionary phase Egyptian Nubian Shield

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Performance Evaluation and Effectiveness of the Reverberation Room

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Sound & Vibration 2021年第1期55卷 43-55页

作者： mohamed abd-Elbasseer Hatem Kh mohamed Acoustics Laboratory National Institute of Standards(NIS)GizaEgypt

This research presents a thorough evaluation of the reverberation room at Acoustics Laboratory in National Institute of Standards(NIS)according to the related international *** evaluation aims at examining the room performance and exploring its effectiveness in the frequency range from 125 Hz to 10000 Hz according to the international standard *** room,which was designed and built several years ago,is an irregular rectangular shape free from *** volume is about 158.84 m^(3),which meets the requirement of the ISO 354 standard Lmax<1.9V^(1/3).Cut-off frequencies of one and one-third octave are 63 Hz and 100 Hz respectively;however Schroder frequency is 400 *** of cut-off frequency and modal density showed adequate modes that give acceptable uniformity starting comfortably from frequency of 125 *** room has a reverberation time that is suitable for its size over the frequency range of *** room sound absorption surface area and its sound absorption coefficient satisfy the criteria given in ISO 3741 and ISO *** is an accepted diffuse sound field inside the room due to the standard deviation of measured sound level,which is less than 1.5 dB over all the frequency *** only exception was 125 Hz which may be due to a lack of diffusivity of the sound field at this *** evaluation proves that the NIS reverberation room is in full agreement with the international standards,which in turns qualifies the room to host measurements inside without concerns.

关键词： Reverberation room cut-off frequency sound absorption spatial uniformity modal counts

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Privacy-preserved learning from non-i.i.d data in fog-assisted IoT:A federated learning approach

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Digital Communications and Networks 2024年第2期10卷 404-415页

作者： mohamed abdel-Basset Hossam Hawash Nour Moustafa Imran Razzak mohamed abd Elfattah Faculty of Computers and Informatics Zagazig UniversityZagazigSharqiyah44519Egypt School of Engineering and Information Technology University of New South Wales@ADFACanberraACT2600Australia Deakin University Geelong Waurn Ponds CampusAustralia Computer Science Department Misr Higher Institute for Commerce and ComputersMansoura35511Egypt

With the prevalence of the Internet of Things(IoT)systems,smart cities comprise complex networks,including sensors,actuators,appliances,and cyber *** complexity and heterogeneity of smart cities have become vulnerable to sophisticated cyber-attacks,especially privacy-related attacks such as inference and data poisoning *** Learning(FL)has been regarded as a hopeful method to enable distributed learning with privacypreserved intelligence in IoT *** though the significance of developing privacy-preserving FL has drawn as a great research interest,the current research only concentrates on FL with independent identically distributed(i.i.d)data and few studies have addressed the non-i.i.d *** is known to be vulnerable to Generative Adversarial Network(GAN)attacks,where an adversary can presume to act as a contributor participating in the training process to acquire the private data of other *** paper proposes an innovative Privacy Protection-based Federated Deep Learning(PP-FDL)framework,which accomplishes data protection against privacy-related GAN attacks,along with high classification rates from non-i.i.d ***-FDL is designed to enable fog nodes to cooperate to train the FDL model in a way that ensures contributors have no access to the data of each other,where class probabilities are protected utilizing a private identifier generated for each *** PP-FDL framework is evaluated for image classification using simple convolutional networks which are trained using MNIST and CIFAR-10 *** empirical results have revealed that PF-DFL can achieve data protection and the framework outperforms the other three state-of-the-art models with 3%–8%as accuracy improvements.

关键词： Privacy preservation Federated learning Deep learning Fog computing Smart cities

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Tagetones A and B, new cytotoxic monocyclic diterpenoids from flowers of Tagetes minuta

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Chinese Journal of Natural Medicines 2017年第7期15卷 546-549页

作者： Sabrin Ragab mohamed Ibrahim Gamal abd Allah mohamed Department of Pharmacognosy and Pharmaceutical Chemistry College of Pharmacy Taibah University Al-Madinah Al-Munawarah 30078 Saudi Arabia Department of Natural Products and Alternative Medicine Faculty of Pharmacy King Abdulaziz University Jeddah 21589 Saudi Arabia

Tagetones A(1) and B(2), two new monocyclic diterpenoids were isolated from the n-hexane fraction of fresh flowers of Tagetes minuta L.(Asteraceae). Their structures were established by multiple spectroscopic methods(IR, HR-ESI-MS, and 1D-, and 2D-NMR), in addition to comparison with literature data. Compound 1 showed cytotoxic activity towards MCF7 and A549 cancer cells with IC_(50) values being 4.68 and 4.24 μmol·L^(-1), respectively, compared to doxorubicin(IC_(50) 0.13 and 1.12 μmol·L^(-1), respectively). Compound 2 also exhibited significant activity against HCT116 cancer cells(IC_(50), 6.30 μmol·L^(-1)).

关键词： Tagetes minuta Asteraceae Monocyclic diterpenoids Tagetones Cytotoxic

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Series solution of a natural convection flow for a Carreau fluid in a vertical channel with peristalsis

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Journal of Hydrodynamics 2015年第6期27卷 969-979页

作者： abd ELMABOUD Y. MEKHEIMER Kh.S. mohamed mohamed S. Mathematics Department Faculty of Science and ArtsKhulaisUniversity Of Jeddah Mathematics Department Faculty of ScienceAl-Azhar University(Assiut Branch) Mathematics Department Faculty of ScienceTaif University Hawia Mathematics Department Faculty of ScienceAl-Azhar University

An analysis has been achieved to study the natural convection of a non-Newtonian fluid （namely a Carreau fluid） in a vertical channel with rhythmically contracting walls. The Navier-Stokes and the energy equations are reduced to a system of non- linear PDE by using the long wavelength approximation. The optimal homotopy analysis method （OHAM） is introduced to obtain the exact solutions for velocity and temperature fields. The convergence of the obtained OHAM solution is discussed explicitly. Numerical calculations are carried out for the pressure rise and the features of the flow and temperature characteristics are analyzed by plotting graphs and discussed in detail.

关键词： homotopy analysis method (HAM) peristaltic transport carreau fluid heat transfer natural convection flow

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Measurements of natural radionuclides in soil samples from Upper Egypt

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Nuclear Science and Techniques 2008年第5期19卷 302-307页

作者： Shaban Ramadan mohamed HARB Khaled SALAHEL DIN abd Elbaset ABBADY mohamed abd Elleh ALI Rolf MICHEL Physics Department Faculty of ScienceSouth Valley University Center for Radiation Protection and Radioecology Hanover University (ZSR)

This paper presents the results of natural radioactivity measured for the soil of Qena using gamma-ray spectrometry at ZSR,Hanover University,*** samples of radioactive concentrations of ^(238)U-series (^(234)Th, ^(214)pb,and^(214)Bi),^(232)Th-series (^(228)Ac,^(212)pb,and ^(208)T1) and ^(40)K were *** objectives were set:(1) activity levels by surface soil sampling at 0～30 cm depth,(2) dose rates of gamma radiation,radium equivalent,index hazard, and effective dose,and (3) ambient dose rates.

关键词：土壤环境放射能 γ光谱测定法辐射暴露环境剂量

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Entropy Generation for Flow and Heat Transfer of Sisko-Fluid Over an Exponentially Stretching Surface

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Computers, Materials & Continua 2020年第1期62卷 37-59页

作者： mohamed abd El-Aziz A.M.Aly Department of Mathematics Faculty of ScienceKing Khalid UniversityAbha61411Saudi Arabia Department of Mathematics Faculty of ScienceHelwan UniversityHelwan-Cairo11795Egypt Department of Mathematics Faculty of ScienceSouth Valley UniversityQena83523Egypt

In the present study,the effects of the magnetic field on the entropy generation during fluid flow and heat transfer of a Sisko-fluid over an exponentially stretching surface are *** similarity transformations are used to transfer the governing partial differential equations into a set of nonlinear-coupled ordinary differential ***-Kutta-Fehlberg method is used to solve the governing *** effects of magnetic field parameter,local slip parameterλ,generalized Biot numberγ,Sisko fluid material parameter,Eckert number Ec,Prandtl number Pr and Brinkman number Br at two values of power law index on the velocity,temperature,local entropy generation number N_(G) and Bejan number Be are ***,the tabular forms for local skin friction coefficient and local Nusselt number under the effects of the physical parameters are *** current results are helpful in checking the entropy generation for *** is found that,an extra magnetic field parameter makes higher Lorentz force that suppresses the *** shear thinning fluids(n<1),the temperature dominates and the velocity *** entropy generation number is more for larger generalized Biot number,magnetic field parameter and Brinkman *** local skin friction coefficient increases as magnetic field parameter and material parameter are increase and it decreases as local slip parameter *** local Nusselt number decreases as magnetic field parameter,local slip parameter and Eckert number are increase,while it increases as material parameter,generalized Biot number and Prandtl number are increase.

关键词： Boundary layer entropy generation exponentially stretching surface magnetic field sisko-fluid

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MHD Boundary Layer Flow of a Power-Law Nanofluid Containing Gyrotactic Microorganisms Over an Exponentially Stretching Surface

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Computers, Materials & Continua 2020年第2期62卷 525-549页

This study focusses on the numerical investigations of boundary layer flow for magnetohydrodynamic(MHD)and a power-law nanofluid containing gyrotactic microorganisms on an exponentially stretching surface with zero nanoparticle mass flux and convective *** nonlinear system of the governing equations is transformed and solved by Runge-Kutta-Fehlberg *** impacts of the transverse magnetic field,bioconvection parameters,Lewis number,nanofluid parameters,Prandtl number and power-law index on the velocity,temperature,nanoparticle volume fraction,density of motile microorganism profiles is *** addition,the impacts of these parameters on local skin-friction coefficient,local Nusselt,local Sherwood numbers and local density number of the motile microorganisms are *** results reveal that the power law index is considered an important factor in this *** to neglecting the buoyancy force term,the bioconvection and nanofluid parameters have slight effects on the velocity *** resultant Lorentz force,from increasing the magnetic field parameter,try to decrease the velocity profiles and increase the rescaled density of motile microorganisms,temperature and nanoparticle volume fraction ***,an augmentation of power-law index drops the reduced local skin-friction and reduced Sherwood number,while it increases reduced Nusselt number and reduced local density number of motile microorganisms.

关键词： Bioconvection gyrotactic microorganisms magnetohydrodynamic nanofluid boundary layer power-law

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Degree-Based Moment Estimation for Ordered Networks

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Journal of Systems Science & Complexity 2017年第3期30卷 721-733页

作者： LI Wenlong YAN Ting abd ELGAWAD mohamed QIN Hong Department of Statistics and Hubei Key Laboratory of Mathematical Sciences Central China Normal UniversityWuhan 430079China Department of Mathematics Faculty of ScienceBenha UniversityBenha 13518Egypt

The edges between vertices in networks take not only the common binary values, but also the ordered values in some situations(e.g., the measurement of the relationship between people from worst to best in social networks). In this paper, the authors study the asymptotic property of the moment estimator based on the degrees of vertices in ordered networks whose edges are ordered random variables. In particular, the authors establish the uniform consistency and the asymptotic normality of the moment estimator when the number of parameters goes to infinity. Simulations and a real data example are provided to illustrate asymptotic results.

关键词： Asymptotic normality consistency moment estimators increasing number of parameters,ordered network.

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Response of slope surface roughness to wave-induced erosion during water level fluctuating

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Journal of Mountain Science 2020年第4期17卷 871-883页

作者： GU Ju LIU Gang abd ELBASIT mohamed Ahmed mohamed SHI Hong-qiang State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China Agricultural Research Council Institute for SoilClimate&WaterPrivate Bag X79Pretoria 0001South Africa

The bank slopes in hydro-fluctuation areas of reservoirs or lakes suffer from severe erosion due to an absence of protection. Waves are one of the important external forces that cause bank erosion and slope failures. However, the processes and quantified impacts of wave-induced erosion on slopes remain unclear under different water level-fluctuation conditions. This paper focuses on the characteristics of wave-induced slope erosion under three conditions: water level dropping(WLD), fixed(WLF) and rising(WLR). A steel tank with glass pane was used to simulate the wave-induced slope erosion in the three treatments. The slope elevation data were collected by using the method of the pin meter for every 15 minutes from the beginning to the end, a total of 5 times during all treatments. These data were processed by using software(SURFER 9.0) to get the slope micro-topography and the erosion volume. Then the temporal and spatial change of slope erosion was analysed according to the erosion amount or erosion rate calculated based on bulk density of slope soil. The results demonstrated that the soil erosion rates for different water level changing treatments are in the following order: WLR>WLD>WLF. For the erosion spatial variation, the middle part of the slope was the major source of sediment in the WLD. The upper part of the slope was the major source of the sediment for the other two treatments. Compared with the standard deviation(SD), the coefficient of variation(CV) based on the SD is more representative of variations in the soil surface roughness(SSR). Furthermore, the good fit between the SSR and soil erosion rate have the potential to be used to predict soil erosion. Above all, the injection angle of the wave determined the rate of erosion to some extent, and the fall-back flow of the wave could also influence the extent of erosion, deposition, and bank morphology. It is vital to choose the appropriate index(SD or CV) in the three water levels to improve the predict

关键词： Bank erosion Erosion rate Micro topography Soil surface roughness Breaking point

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