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Constraints of mantle and Crustal Sources Interaction during Orogenesis of Pre-and Post-collision Granitoids from the Northern Arabian-Nubian Shield:A Case Study from Wadi El-Akhder Granitoids,Southern Sinai,Egypt

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Acta Geologica Sinica(English Edition) 2021年第5期95卷 1527-1550页

作者： moustafa m.mOGAHED khaled m.abdelfadil Geology Department Faculty of ScienceBenha UniversityBenha 13518Egypt Geology Department Faculty of ScienceSohag UniversitySohag 82524Egypt

The Egyptian older and younger granitic rocks emplaced during pre-and post-collision stages of Neoproterozoic Pan-African orogeny,respectively,are widely distributed in the southern Sinai Peninsula,constituting 70% of the basement *** Wadi El-Akhder,southwestern Sinai,is a mountainous terrain exposing two granitoid suites,namely the Wadi El-Akhder Older Granites(AOG)and the Homra Younger Granites(HYG).The AOG(granodiorites with subordinate tonalite compositions)have geochemical characteristics of medium-K calc-alkaline,metaluminous to mildly peraluminous granitoids formed in an island-arc environment,which are conformable with well-known Egyptian older granitoids rocks,whereas the HYG display calc-alkaline to slightly alkaline nature,peraluminous syeno-,monzogranites and alkali feldspar granites matching well those of the Egyptian younger *** respect to the AOG granitoids,the HYG granites contain lower Al_(2)O_(3),FeO^(*),mgO,mnO,CaO,TiO_(2),Sr,Ba,and V,but higher Na_(2)O,K_(2)O,Nb,Zr,Th,and *** AOG are generally characterized by enrichment in LILE and LREE and depletion in HFSE relative to N-mORB values(e.g.,negative Nb and Ta anomalies).The geochemical features of the AOG follow assimilation-fractional crystallization(AFC)trends indicative of extensive crustal contamination of magma derived from a mantle *** chemical characteristics of the AOG are remarkably similar to those of subduction-related granitoids from the ArabianNubian Shield(ANS).The compositional variations from monzogranites through syenogranites to alkali feldspar granite within HYG could not be explained by fractional crystallization *** the whole-rock composition of the HYG to melts generated by experimental dehydration melting of meta-sedimentary and magmatic rocks reveals that they appear to be derived by extended melting of psammitic and pelitic metasediments,which is similar to the most of younger granitic suites in the ANS.

关键词： older and younger granitoids mantle-crust interaction assimilation-fractional crystallization(AFC) southern Sinai Arabian-Nubian Shield

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Origin and Petrogenetic Implications of Spessartine Garnet in Highly-Fractionated Granite from the Central Eastern Desert of Egypt

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Acta Geologica Sinica(English Edition) 2020年第3期94卷 763-776页

作者： mabrouk SAmI Theodoros NTAFLOS Haroun A.mOHAmED Esam S.FARAHAT Christoph HAUZENBERGER Nasser m.mAHDY khaled m.abdelfadil Douaa FATHY Geology Department Faculty of ScienceMinia UniversityEl-Minia 61519Egypt Department of Lithospheric Research University of ViennaAlthanstrasse 14A-1090 ViennaAustria Institute of mineralogy and Petrology Karl-Franzens UniversityGrazAustria Nuclear materials Authority P.O.530El-MaadiCairoEgypt Geology Department Faculty of ScienceSohag UniversityEgypt

A highly-fractionated garnet-bearing muscovite granite represents the marginal granitic facies of the Abu-Diab multiphase pluton in the Central Eastern Desert of Egypt. New electron microprobe analyses(EmPA) and laser ablation inductively coupled plasma mass spectrometry(LA-ICP-mS) data from garnets are reported, in order to constrain their origin and genesis. Garnet in the Abu-Diab host granite is euhedral to subhedral, generally homogeneous and, in rare cases, it shows weak zonation. The garnet contains appreciable amounts of mnO and FeO, with lesser amounts of mgO and CaO, yielding an end-member formula of Sps61–72Alm25–35Prp1–4Adr0–1. moreover, it is depleted in large ion lithophile elements(LILE) with lower values of Ba, Nb and Sr relative to the primitive mantle. Additionally, it contains high concentrations of HREE and Y and their REE pattern shows strong negative Eu anomalies. The garnet was crystallized under relatively low temperature(646°C–591°C) and pressure(mical features indicate that the garnet is magmatic in origin and is chemically similar to that from highly-fractionated A-type granite. It was probably formed at the expense of biotite in a highly-evolved mnO-rich magma and/or by hydroxyl complexing of mn during the ascending fluid phases.

关键词： spessartine garnet LA-ICP-mS A-type granite Abu-Diab Egypt

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Role of magmatism and Related-Exsolved Fluids during Ta-Nb-Sn Concentration in the Central Eastern Desert of Egypt:Evidences from mineral Chemistry and Fluid Inclusions

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Journal of Earth Science 2023年第3期34卷 674-689页

作者： mohamed Abd El monsef mabrouk Sami Fatma Toksoy‐Köksal Rainer Abart martin Ondrejka khaled mabdelfadil Geology Department Faculty of ScienceTanta University31527 TantaEgypt Geology Department Faculty of ScienceMinia University61519 El-MiniaEgypt Department of Geological Engineering Middle East Technical University06800 AnkaraTurkey Department of Lithospheric Research University of Vienna1090 ViennaAustria Department of mineralogy Petrology and Economic GeologyComenius UniversityBratislavaSlovakia Department of Geology Faculty of ScienceSohag University82524 SohagEgypt Department of Physics and Earth Sciences Jacobs University28759 BremenGermany

The rare metals of Abu Dabbab area in the Central Eastern Desert of Egypt have been investigated for their mineralogy and conditions of precipitation using combination of EmPA and fluid inclusions studies,in order to delineate the source,mechanism of formation and evolutionary model for these economic ***(Ta-Nb-Sn)-bearing minerals at the Abu Dabbab area include columbite group minerals(CGms),wodginite and *** both granitic intrusion and its enclosed quartz veins,most of zoned CGms and cassiterite grains are commonly characterized by a well-developed twostage ***,columbite-(mn)(CGm-Ⅰ)represents the early formed phase of CGms that is characterized by high mn#values(0.64-0.92)with quite low Ta#values(0.13-0.49).It was invaded by Ta-rich phases including tantalite-(mn)(CGm-Ⅱ;Ta#=0.13-0.49)and wodginite,which contain high Ta_(2)O_(5)and SnO_(2)(17.91 wt.%).In regard to cassiterite,there are distinct compositional differences between the early-phase cassiterite(Cst-Ⅰ)and the late-phase one(Cst-Ⅱ),where the latter is enriched in Ta_(2)O_(5),Nb_(2)O_(5)and *** chemistry and textural criteria of the early stage CGm-Ⅰand Cst-Ⅰ,all are indicative of magmatic ***,the latter CGm-Ⅱ,wodginite and Cst-Ⅱwere influenced by the late magmatic Ta-rich *** inclusions microthermometry shows criteria of phase separation represented by both boiling and fluid *** initial fluid was supposed to be of magmatic origin(magmatic CH4),that was consequently influenced by fluid mixing/dilution with post-hydrothermal/meteoric water with respect to the decompression process during *** construction gave rise to an estimate P-T conditions(T=330-370℃,P=22-50 mPa).The fluid inclusions’microthermometry supports a transition between magmatic and late to post-hydrothermal activities in addition to surface-derived fluid(meteoric fluid?)in a part as main source for the polymetallic deposits.

关键词： columbite-group minerals wodginite cassiterite magmatic-hydrothermal fluid inclusion deposits Abu Dabbab

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Enhanced Parallelized DNA-Coded Stream Cipher Based on multiplayer Prisoners’Dilemma

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Computers, materials & Continua 2023年第5期75卷 2685-2704页

作者： khaled m.Suwais Faculty of Computer Studies Arab Open UniversityRiyadh11681Saudi Arabia

Data encryption is essential in securing exchanged data between connected *** is the process of transforming readable text into scrambled,unreadable text using secure *** ciphers are one type of an encryption algorithm that relies on only one key for decryption and as well as *** existing encryption algorithms are developed based on either a mathematical foundation or on other biological,social or physical *** technique is to utilise the behavioural aspects of game theory in a stream *** this paper,we introduce an enhanced Deoxyribonucleic acid(DNA)-coded stream cipher based on an iterated n-player prisoner’s dilemma *** main goal is to contribute to adding more layers of randomness to the behaviour of the keystream generation process;these layers are inspired by the behaviour of multiple players playing a prisoner’s dilemma *** implement parallelism to compensate for the additional processing time that may result fromadding these extra layers of *** results show that our enhanced design passes the statistical tests and achieves an encryption throughput of about 1,877 mbit/s,which makes it a feasible secure stream cipher.

关键词： Encryption game theory DNA cryptography stream cipher parallel computing

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A practical application of photogrammetry to performing rib characterization measurements in an underground coal mine using a DSLR camera

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International Journal of mining Science and Technology 2017年第1期27卷 83-90页

作者： Brent A.Slaker khaled m.mohamed mining Engineer Ground Control Branch NIOSH Office of Mine Safety and Health ResearchPittsburghPAUSA

Understanding coal mine rib behavior is important for inferring pillar loading conditions as well as ensuring the safety of miners who are regularly exposed to ribs. Due to the variability in the geometry of underground openings and ground behavior, point measurements often fail to capture the true movement of mine workings. Photogrammetry is a potentially fast, cheap, and precise supplemental measurement tool in comparison to extensometers, tape measures, or laser range meters, but its application in underground coal has been limited. The practical use of photogrammetry was tested at the Safety Research Coal mine, National Institute for Occupational Safety and Health(NIOSH). A commercially available, digital single-lens reflex(DSLR) camera was used to perform the photogrammetric surveys for the experiment. Several experiments were performed using different lighting conditions, distances to subject,camera settings, and photograph overlaps, with results summarized as follows: the lighting method was found to be insignificant if the scene was appropriately illuminated. It was found that the distance to the subject has a minimal impact on result accuracy, and that camera settings have a significant impact on the photogrammetric quality of images. An increasing photograph resolution was preferable when measuring plane orientations; otherwise a high point cloud density would likely be excessive. Focal ratio(F-stop) changes affect the depth of field and image quality in situations where multiple angles are necessary to survey cleat orientations. Photograph overlap is very important to proper three-dimensional reconstruction, and at least 60% overlap between photograph pairs is ideal to avoid unnecessary post-processing. The suggestions and guidelines proposed are designed to increase the quality of photogrammetry inputs and outputs as well as minimize processing time, and serve as a starting point for an underground coal photogrammetry study.

关键词： Photogrammetry Coal mining Underground Rib characterization

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ESSD: Energy Saving and Securing Data Algorithm for WSNs Security

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Computers, materials & Continua 2022年第11期73卷 3969-3981页

作者： manar m.Aldaseen khaled m.matrouk Laiali H.Almazaydeh khaled m.Elleithy Computer Engineering Department Al-Hussein Bin Talal UniversityMa’anJordan Software Engineering Department Al-Hussein Bin Talal UniversityMa’anJordan Computer Science and Engineering Department University of BridgeportCTBridgeportUSA

The Wireless Sensor Networks(WSNs)are characterized by their widespread deployment due to low cost,but the WSNs are vulnerable to various types of *** defend against the attacks,an effective security solution is ***,the limits of these networks’battery-based energy to the sensor are the most critical impediments to selecting cryptographic ***,finding a suitable algorithm that achieves the least energy consumption in data encryption and decryption and providing a highly protected system for data remains the fundamental *** this research,the main objective is to obtain data security during transmission by proposing a robust and low-power encryption algorithm,in addition,to examining security algorithms such as ECC and mD5 based on previous *** this research,the Energy Saving and Securing Data algorithm(ESSD)algorithm is introduced,which provides the message Digest 5(mD5)computation simplicity by modifying the Elliptic Curve Cryptography(ECC)under the primary condition of power *** three algorithms,ECC,mD5,and ESSD,are applied to Low Energy Adaptive Clustering Hierarchy(LEACH)and Threshold-sensitive Energy Efficient Sensor Network Protocol(TEEN)hierarchical routing algorithms which are considered the most widely used in *** results of security methods under the LEACH protocol show that all nodes are dead at 456,496,and 496,respectively,to ECC,mD5,and *** results of security methods under the TEEN protocol show that the test ends at 3743,4815,and 4889,respectively,to ECC,mD5,and *** on these results,the ESSD outperforms better in terms of increased security and less power *** addition,it is advantageous when applied to TEEN protocol.

关键词： Cryptography ECC energy consumption ESSD LEACH mD5 RSA TEEN WSNs

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Torsional Wave in a Dissipative Cylindrical Shell Under Initial Stresses

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Computers, materials & Continua 2022年第2期70卷 3021-3030页

作者： mahmoud m.Selim khaled A.Gepreel Department of mathematics-College of Sciences&Humanities in Al Aflaj Prince Sattam bin Abdulaziz UniversityAl-Aflaj11912KSA Department of mathematics Suez Faculty of ScienceSuez UniversityEgypt Department of mathematics Faculty of ScienceTaif UniversityTaif21944Saudi Arabia

The dispersion relation of torsional wave in a dissipative,incompressible cylindrical shell of infinite length incorporating initial stresses effects is *** governing equation and closed form solutions are derived with the aid of Biot’s *** velocity and damping of torsional wave are obtained analytically and the influences of dissipation and initial stresses are studied in *** proposed a new method for obtaining the phase and damping velocities of torsional wave in a complex *** results analyzing the torsional wave propagation incorporating initial stress effects are analyzed and presented in *** analytical and numerical solutions reveal that,the dissipation as well as the initial stresses have notable impacts on the phase velocity of torsional wave in a pre-stressed dissipative cylindrical *** numerical results reveal that,the initial stresses and dissipation,considerably,effect the phase velocity of the torsional *** has been observed that,any change in dissipation parameter(δ)produces a substantial change in damping velocity of torsional *** addition,it can be seen that,the phase velocity increases as the initial stress parameter ***,the result of numerical simulation illustrated the influence of dissipation and initial stresses on damping and phase velocities of torsional wave *** conclusion made shown the consistency with the Biot’s incremental deformation theory,and the effective on model such as engineering mechanics and displacement of particles.

关键词： Propagation torsional wave dissipation cylindrical shell initial stress

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State-space approach to vibration of gold nano-beam induced by ramp type heating

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Nano-micro Letters 2010年第3期2卷 139-147页

作者： Hamdy m.Youssef khaled A.Elsibai mathematical Department-Faculty of Education-Alexandria University-Egypt mathematics Department Faculty of ScienceMansoura University

In the nanoscale beam,two effects become *** is the non-Fourier effect in heat conduction and the other is the coupling effect between temperature and strain *** the present study,a generalized solution for the generalized thermoelastic vibration of gold nano-beam resonator induced by ramp type heating is *** solution takes into account the above two ***-space and Laplace transform methods are used to determine the lateral vibration,the temperature,the displacement,the stress and the strain energy of the *** effects of the relaxation time and the ramping time parameters have been studied.

关键词： Thermoelasticity Euler-Bernoulli equation Gold nano-beam Ramp type heating

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Advantages and disadvantages of nuclear reactions used in reactors or cyclotrons,in addition to a theoretical study based on photodisintegration on natural indium for^(111)Ag production

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Nuclear Science and Techniques 2022年第2期33卷 1-13页

作者： khaled m.El-Azony Nader m.A.mohamed Dalal A.Aloraini Radioactive Isotopes and Generators Department Hot Labs.CenterEgyptian Atomic Energy AuthorityP.O.Box 13759CairoEgypt Reactors Department Egyptian Atomic Energy AuthorityP.O.Box 13759CairoEgypt Physics Department College of SciencePrincess Nourah Bint Abdulrahman UniversityRiyadhKingdom of Saudi Arabia

Production routes were recorded on available reactions for^(111)Ag production from nuclear reactors or cyclotrons using a natural palladium target based on^(110)Pd(n,γ)and^(110)pd(d,n)reactions,respectively.^(nat)Cd(γ,x)based on^(110)Cd(γ,p)has also been studied as a prospective reaction for the production of^(111)***,these nuclear reactions are difficult to utilize because,in some cases,they reduce the specific activity of^(111)*** is a consequence of the stable silver isotopes produced in high *** isotopes include^(107,109)Ag and,in other cases,the high impurity of silver radioisotopes,such as^(110)m,^(106)m,^(105)Ag,that are produced during parallel nuclear *** to a scarcity of data regarding the(γ,α)reaction,the gamma reaction on natural indium for^(111)Ag production based on the^(115)In(γ,α)reaction was *** ^(nat)In(γ,α)reaction satisfies the criteria as a possible reaction to produce^(111)Ag with a sufficient yield and purity as consequence of the high^(115)In(95.7%)abundance as an enriched form and a relatively soft background caused by the parallel nuclear reactions.

关键词： Silver-111 Nuclear data Natural cadmium Natural palladium Natural indium

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Control of a Two-wheeled machine with Two-directions Handling mechanism Using PID and PD-FLC Algorithms

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International Journal of Automation and computing 2019年第4期16卷 511-533页

作者： khaled m. Goher Sulaiman O. Fadlallah School of Engineering University of Lincoln Lincoln LN6 7TS UK mechanical Engineering Department Auckland University of Technology Auckland 1142 New Zealand

This paper presents a novel five degrees of freedom (DOF) two-wheeled robotic machine (TWRm) that delivers solutions for both industrial and service robotic applications by enlarging the vehicle′s workspace and increasing its flexibility. Designing a two-wheeled robot with five degrees of freedom creates a high challenge for the control, therefore the modelling and design of such robot should be precise with a uniform distribution of mass over the robot and the actuators. By employing the Lagrangian modelling approach, the TWRm′s mathematical model is derived and simulated in matlab/Simulink?. For stabilizing the system′s highly nonlinear model, two control approaches were developed and implemented: proportional-integral-derivative (PID) and fuzzy logic control (FLC) strategies. Considering multiple scenarios with different initial conditions, the proposed control strategies′ performance has been assessed.

关键词： Two-wheeled inverted pendulum (IP) with two direction handling Lagrangian formulation proportional-integral-derivative (PID) fuzzy logic control (FLC) under-actuated systems

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