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Geochemistry of an Alaskan-type mafic-ultramafic complex in eastern Desert, egypt:New insights and constraints on the Neoproterozoic island arc magmatism

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Geoscience Frontiers 2019年第3期10卷 941-955页

作者： shehta e.abdallah Shehata Ali Mohamed A.Obeid Geology Department Faculty of Science Zagazig University Geology Department Faculty of Science Minia University Geology Department Faculty of Science Fayoum University Faculty of Petroleum and Mining Sciences Alexandria University (Matrouh Branch)

Mikbi intrusion(MI) is a part of the Neoproterozoic Nubian Shield located along the Ne-SW trending major fracture zones prevailing southern eastern Desert of egypt. In this study, we present for the first time detailed mineralogical and bulk-rock geochemical data to infer some constraints on the parental magma genesis and to understand the tectonic processes contributed to MI formation. Lithologically, it is composed of fresh peridotite, clinopyroxenite, hornblendite, anorthosite, gabbronorite, pyroxene amphibole gabbro, amphibole gabbro and diorite. All rocks have low Th/La ratios(mostly e Zr and Th anomalies excluding significant crustal contamination. They show very low concentrations of Nb, Ta, Zr and Hf together with sub-chondritic ratios of Nb/Ta(2-15) and Zr/Hf(19-35),suggesting that their mantle source was depleted by earlier melting extraction event. The oxygen fugacity(logfO_2) estimated from diorite biotite is around the nickel-nickel oxide buffer(NNO) indicating crystallization from a relatively oxidized magma. Amphiboles in the studied mafic-ultramafic rocks indicate relative oxygen fugacity(i.e. ΔNNO; nickel-nickel oxide) of 0.28-3 and were in equilibrium mostly with 3.77-8.24 wt.% H_2 O_(melt)(i.e. water content in the melt), consistent with the typical values of subduction-related magmas. Moreover, pressure estimates(0.53-6.79 kbar) indicate polybaric crystallization and suggest that the magma chamber(s) was located at relatively shallow crustal levels. The enrichment in LILe(e.g., Cs, Ba, K and Sr) and the depletion in HFSe(e.g., Th and Nb) relative to primitive mantle are consistent with island arc signature. The olivine, pyroxene and amphibole compositions also reflect arc affinity. These inferences suggest that their primary magma was derived from partial melting of a mantle source that formerly metasomatized in a subduction zone setting. Clinopyroxene and bulkrock data are consistent with orogenic tholeiitic affinity. Conse

关键词： Alaskan-type complex Neoproterozoic Arc magmatism eastern desert egypt

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The Petrological and Geochemical evolution of ediacaran Rare-Metal Bearing A-type Granites from the Jabal Aja Complex, Northern Arabian Shield, Saudi Arabia

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Acta Geologica Sinica(english edition) 2020年第3期94卷 743-762页

作者： shehta e.abdallah Mokhles K.AZeR Abdullah S.AL SHAMMARI Geology Department Faculty of ScienceZagazig University44519ZagazigEgypt Geological Sciences Department National Research Centre12622 DokkiCairoEgypt Faculty of Science Ha’il University2440 Ha’ilSaudi Arabia

New fieldwork, mineralogical and geochemical data and interpretations are presented for the rare-metal bearing A-type granites of the Aja intrusive complex(AIC) in the northern segment of the Arabian Shield. This complex is characterized by discontinuous ring-shaped outcrops cut by later faulting. The A-type rocks of the AIC are late Neoproterozoic post-collisional granites, including alkali feldspar granite, alkaline granite and peralkaline granite. They represent the outer zones of the AIC, surrounding a core of older rocks including monzogranite, syenogranite and granophyre granite. The sharp contacts between A-type granites of the outer zone and the different granitic rocks of the inner zone suggest that the AIC was emplaced as different phases over a time interval, following complete crystallization of earlier batches. The A-type granites represent the late intrusive phases of the AIC, which were emplaced during tectonic extension, as shown by the emplacement of dykes synchronous with the granite emplacement and the presence of cataclastic features. The A-type granites consist of K-feldspars, quartz, albite, amphiboles and sodic pyroxene with a wide variety of accessory minerals, including Fe-Ti oxides, zircon, allanite, fluorite, monazite, titanite, apatite, columbite, xenotime and epidote. They are highly evolved(71.3–75.8 wt% SiO2) and display the typical geochemical characteristics of post-collisional, within-plate granites. They are rare-metal granites enriched in total alkalis, Nb, Zr, Y, Ga, Ta, Ree with low CaO, MgO, Ba, and Sr. eu-negative anomalies(eu/eu* = 0.17–0.37) of the A-type granites reflect extreme magmatic fractionation and perhaps the effects of late fluid-rock interactions. The chemical characteristics indicate that the A-type granites of the AIC represent products of extreme fractional crystallization involving alkali feldspar, quartz and, to a lesser extent, ferromagnesian minerals. The parent magma was derived from the partial melting of

关键词： ring complex rare-metal bearing granites sodic amphibole sodic pyroxene within-plate Arabian Shield

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How Can Lean Manufacturing Lead the Manufacturing Sector during Health Pandemics Such as COVID 19: A Multi Response Optimization Framework

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Computers, Materials & Continua 2021年第2期66卷 1397-1410页

作者： abdallah Ali abdallah Department of Industrial engineering German Jordanian UniversityAmman11841Jordan

Lean manufacturing has been used for the last few decades as a process and performance improvement *** known as Toyota production system(TPS),lean is now used in almost all service and manufacturing sectors to deliver favorable results such as decreased operational cost,increased customer satisfaction,decreased cycle time,and enhanced *** the coronavirus disease(COVID 19)pandemic,the manufacturing sector struggled immensely and could not function well even after lockdown was eased in many *** companies found out there are not ready to conform with new regulations made by authorities in many *** paper proposes the use of simulation and multi response optimization in addition to other typical lean tools in order to arrive at optimum performance at the end of each project through an established optimization *** framework is used in a real case study performed at an aluminum extrusion *** manufacturing helps organizations to operate with smaller number of *** standardizes all processes so that most of the jobs can be done by most of the workers,but this is not enough to create a healthy,sanitized work *** framework utilizes the strengths of lean tools and adds pandemic readiness factor to them to ensure improvement in performance and health pandemic *** of the framework in the case company resulted in 50%reduction in labor,$730000 in expected annual cost savings,reduction in inventory levels,improved employee morale and the achievement of pandemic ready status.

关键词： Lean manufacturing COVID 19 health pandemics simulation desirability index optimization

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A TRUST-ReGION ALGORITHM FOR SOLVING MINI-MAX PROBLeM

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Journal of Computational Mathematics 2018年第6期36卷 776-791页

作者： Bothina e1-Sobky abdallah Abotahoun Department of Mathematics Alexandria University Alexandria Egypt

In this paper, we propose an algorithm for solving inequality constrained mini-max optimization problem. In this algorithm, an active set strategy is used together with mul- tiplier method to convert the inequality constrained mini-max optimization problem into unconstrained optimization problem. A trust-region method is a well-accepted technique in constrained optimization to assure global convergence and is more robust when they deal with rounding errors. One of the advantages of trust-region method is that it does not require the objective function of the model to be convex. A global convergence analysis for the proposed algorithm is presented under some conditions. To show the efficiency of the algorithm numerical results for a number of test problems are reported.

关键词： Mini-max problem Active-set Multiplier method Trust-region Global con-vergence

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Spectrum behavior for the nonlinear fractional point reactor kinetics model

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Nuclear Science and Techniques 2018年第1期29卷 96-109页

作者： Ahmed e.Aboanber abdallah A.Nahla A.A.Hemeda Department of Mathematics Faculty of Science Tanta University

The nonlinear fractional point reactor kinetics equation in the presence of Newtonian temperature reactivity feedback with a multi-group of delayed neutrons,which describes the spectrum behavior of neutron density into the homogenous nuclear reactors, is developed. This system is one of the most important stiff coupled nonlinear fractional differentials for nuclear reactor dynamics. The generalization of Taylor's formula that involves Caputo fractional derivatives is developed in an attempt to overcome the difficulty of the stiffness of the nonlinear fractional differential model. Moreover, the general fractional derivatives are calculated analytically throughout this work. Furthermore, the local and global estimated errors were analyzed, which suggest that the error quantification should take into account the possible grow in time of the error. This observation provides a motivation for going beyond more classical local-in-time concepts of error(local truncation error). The neutron density response with time is analyzed for the anomalous diffusion, sub-diffusion, and super-diffusion processes.

关键词： Nonlinear fractional Generalized Taylor’s formula Point kinetics Multi-group delayed neutrons Temperature feedback reactivity

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Developed mathematical technique for fractional stochastic point kinetics model in nuclear reactor dynamics

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Nuclear Science and Techniques 2018年第9期29卷 197-213页

作者： Ahmed e.Aboanber abdallah A.Nahla Adel M.edress Department of Mathematics Faculty of Science Taibah University Department of Mathematics Faculty of Science Tanta University

Fractional stochastic kinetics equations have proven to be valuable tools for the point reactor kinetics model, where the nuclear reactions are not fully described by deterministic relations. A fractional stochastic model for the point kinetics system with multi-group of precursors,including the effect of temperature feedback, has been developed and analyzed. A major mathematical and inflexible scheme to the point kinetics model is obtained by merging the fractional and stochastic technique. A novel split-step method including mathematical tools of the Laplace transforms, Mittage–Leffler function, eigenvalues of the coefficient matrix, and its corresponding eigenvectors have been used for the fractional stochastic matrix differential equation. The validity of the proposed technique has been demonstrated via calculations of the mean and standard deviation of neutrons and precursor populations for various reactivities: step, ramp, sinusoidal, and temperature reactivity feedback. The results of the proposed method agree well with the conventional one of the deterministic point kinetics equations.

关键词： Ito stochastic point kinetics equations Temperature feedback effects Wiener process Fractional calculus Mittage–Leffler function

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An Attention-Based Approach to enhance the Detection and Classification of Android Malware

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Computers, Materials & Continua 2024年第8期80卷 2743-2760页

作者： abdallah Ghourabi Department of Computer Science College of Computer and Information SciencesJouf UniversitySakaka72388Saudi Arabia

The dominance of Android in the global mobile market and the open development characteristics of this platform have resulted in a significant increase in *** malicious applications have become a serious concern to the security of Android *** address this problem,researchers have proposed several machine-learning models to detect and classify Android malware based on analyzing features extracted from Android ***,most existing studies have focused on the classification task and overlooked the feature selection process,which is crucial to reduce the training time and maintain or improve the classification *** current paper proposes a new Android malware detection and classification approach that identifies the most important features to improve classification performance and reduce training *** proposed approach consists of two main ***,a feature selection method based on the Attention mechanism is used to select the most important ***,an optimized Light Gradient Boosting Machine(LightGBM)classifier is applied to classify the Android samples and identify the *** feature selection method proposed in this paper is to integrate an Attention layer into a multilayer perceptron neural *** role of the Attention layer is to compute the weighted values of each feature based on its importance for the classification *** evaluation of the approach has shown that combining the Attention-based technique with an optimized classification algorithm for Android malware detection has improved the accuracy from 98.64%to 98.71%while reducing the training time from 80 to 28 s.

关键词： Android malware malware detection feature selection attention mechanism LightGBM mobile security

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Seismic performance of high-rise buildings in selected regions in Saudi Arabia according to different seismic codes

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earthquake engineering and engineering Vibration 2021年第1期20卷 179-191页

作者： Sayed Mahmoud Mohamed Alsearheed Waleed abdallah Department of Civil and Construction engineering College of EngineeringImam Abdulrahman Bin Faisal UniversitySaudi Arabia Department of Building engineering College of ArchitectureImam Abdulrahman Bin Faisal UniversitySaudi Arabia Department of Civil engineering College of Engineering at MatariaHelwan UniversityCairoEgypt

The design code for each country is revised and updated based on an expected zone’s seismic intensities,geotechnical site classifications,structural systems,construction materials and methods of construction in order to provide more realistic considerations of seismic demand,seismic response,and seismic *** on the aforementioned provisions,structures designed according to different seismic codes may yield different performances for the same level of *** study aims to investigate and compare the induced responses related to the earthquake-resistant design of reinforced concrete(RC)buildings according to the Saudi building code(SBC-301),American code(ASCe-7),uniform building code(UBC-97),and european code(eC-8).In order to account for the provision regarding the hazard specification and its effect on the induced seismic responses,four regions in the Kingdom of Saudi Arabia with different seismic levels are *** code provisions related to the specification of site classification and its effect on the induced design base shear are investigated as *** differences are observed in the induced responses with the variation in seismic design codes for the considered seismic hazards and site classifications.

关键词： high-rise building SBC-301 international seismic codes seismic zones site classifications

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Germination and Photosynthetic Responses to Salinity and Alkalinity in Avicenna marina Propagules

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Phyton-International Journal of experimental Botany 2022年第5期91卷 1015-1026页

作者： abdallah Atia Ahmed abdallah Hussain Barhoumi Zouhaier Department of Biology College of Arts and Science Mahayel AsirKing Khalid UniversityAbha61413Saudi Arabia Research Unit Nutrition and Nitrogen Metabolism and Stress ProteinDepartment of BiologyFaculty of Sciences of TunisCampus Universitaire El Manar ITunis1068Tunisia Department of Biology King Khalid UniversityAbha61413Saudi Arabia Faculty of Science Abu HarazGezira UniversityWed Medani21111Sudan Laboratory of extremophile Plants Biotechnology Center of Borj CedriaUniversity Tunis El ManarTunis1068Tunisia

Avicenna marina(Forssk.)Vierh is a halophytic *** reproductive unit is green and has photosynthetic *** are naturally exposed to fluctuations in some abiotic factors at the soil surface,including salinity and *** objective of this study was to determine the effects of two salts including NaCl and NaHCO_(3)on germination processes and discuss the relationships between cotyledon photosynthesis and embryo axis growth in *** *** propagules came from Al Birk,located on the shoreline of the Saudi Red *** results showed that the studied salts did not affect neither the final germination percentage nor the embryo axis ***,rooting and root growth were delayed by both salts at 300 mM and were strongly inhibited by 600 mM NaHCO_(3).Both NaCl and NaHCO_(3)reduced the photosynthetic *** two salts did not affect the other photosynthetic parameters,including stomatal conductance,net transpiration,and intercellular CO_(2).Thereafter,the reduction in net photosynthesis was not related to any limitation of stomatal *** early germination phase was independent of cotyledon photosynthesis,whereas rooting and root growth may be limited by reduced photosynthesis under NaCl and NaHCO_(3).

关键词： Avicenna marina propagules cotyledons embryo growth germination photosynthesis alkalinity salinity

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Geochemical Stream Sediment Survey in the Wadi Umm Rilan Area,South eastern Desert,egypt:A New Occurrence for Gold Mineralization

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Acta Geologica Sinica(english edition) 2017年第3期91卷 1041-1062页

作者： Mohamed abdallah Gad DARWISH Geology Department Faculty of ScienceAswan University

The present paper investigates the stream sediment geochemistry, behavior of gold and associated elements, delineates Au-anomalous sites and defines related sources in the Wadi Umm Rilan area. Fifty three major and trace elements were analyzed using ICP-MS and treated applying various statistical and mapping techniques. The results showed a significant difference of mean and median Au and most chemical elements in the three portions of the area, and higher values were recorded in the western portion. Furthermore, Au-anomalous sites appeared in upper and lower parts of the Wadi Umm Rilan, along the tributaries of metavolcanic unit and near granitoid contacts. This indicates the main source of Au mineralization is related to emplacement of granitoid plutons and accompanying hydrothermal solutions. There are significant indications for the presence of more than one mineralization event forming a probable single major episode of mineralization in the area, involving Au, Pb and U mineralizations. Geology, geomorphologic aspects and weathering processes could control stream sediment geochemistry, anomalies of Au and associated elements, elemental association and their dispersion patterns. Therefore, the area is fruitful and regarded as a promising target for Au exploration, using Ag, As, Sb, Cd, Cs, and TI as pathfinder elements.

关键词： geochemical survey stream sediments Au mineralization Wadi Umm Rilan area southeastern Desert egypt

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