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Constrained Groove Pressing(CGP):Die Design,Material Processing and Mechanical Characterization

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Fluid Dynamics & Materials Processing 2019年第3期15卷 171-185页

作者： Reham reda Faculty of Engineering Suez UniversitySuez 43721Egypt

Constrained groove pressing(CGP)is a severe plastic deformation(SPD)technique used as a strengthening method for sheet *** the current work,an optimal/cost-saving design for CGP dies was attained using the stress analysis tool in SolidWorks Simulation Xpress *** study examined low-cost and widely industrially applied aluminium materials,i.e.,pure 1050 Al and 5052 Al *** material was subjected to three passes of the CGP process using a 150 tons capacity *** both materials,inter-pass annealing treatment was undertaken before the third *** effect of the number of CGP passes on the microstructure and tensile properties was studied after each *** CGPed pure 1050 Al with respect to the as-received material,the ultimate tensile strength(UTS),yield strength(YS)and YS/UTS ratio increased with an increasing number of CGP passes until the second pass,while elongation decreased with the number of *** CGPed 5052 Al alloy,the UTS and YS increased after the first pass and then decreased after the second *** in the elongation and YS/UTS ratio of 5052 Al alloy after the CGP process were *** inter-pass annealing and applying the third CGP pass,the strength of pure 1050 Al decreased,and that of 5052 Al alloy increased,which was attributed to the influence of composition on their *** strength-ductility balance decreased with an increasing number of CGP passes in both materials.

关键词： CGP die design 1050 Al 5052 Al processing microstructure tensile properties

A poroelastic numerical model for simulation of hydraulic fracture propagation:Application to Upper Safa formation-Western Desert-Egypt

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Petroleum Research 2020年第1期5卷 39-51页

作者： reda Abdel Azim Petroleum Engineering Department American University of KurdistanDohoukIraq

The hydraulic fracturing in tight sand formations has a significant importance in improving its production *** this study,a poroelastic numerical model is presented in order to study the reservoirs and rock mechanical properties that affect the propagation of the hydraulic *** poroelastic model simulate fully coupled fluid flow,pressures and stress changes by using finite element *** results show that the formation permeability and fracture toughness are key parameters in the design of hydraulic fracture treatment.A case study applied in Upper Safa formation in a well-located western desert *** formation is very tight with permeability of 0.1md and the objective here is to optimize the design procedures for hydraulic fracture *** results show that the formation needs to be pumped for about 5min to produce hydraulic fracture length of 182 *** addition,the total pumping time(30 min)is vital to produce the desired total fracture length of 1000 ft.

关键词： Fracture propagation Finite element Upper Safa formation Poroelastic Leak off model

A hybrid simulation approach to evaluate stimulation micro-seismic events and production potential of fractured geothermal reservoirs

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Petroleum Research 2020年第2期5卷 131-143页

作者： reda Abdel Azim Petroleum Engineering Department American University of Kurdistan Zakho Rd.99641DohoukIraq

This study presents an integrated approach to simulate fluid flow and to predict the micro seismic eventsduring stimulation and circulation of cold water over a longer term in geothermal reservoirs. The integrated approach based on new three dimensional fully coupled thermo-poroelastic numerical model forevaluation of energy recoverable. In the presented approach, the fracture aperture due to fractureslippage is calculated by shear and dilation. The shear slippage is controlled by the concept of shearfailure using linear Mohr-Coulomb criterion. The numerical model is validated against an analytical Oda’smodel for permeability tensor calculation and against an analytical solution for thermo-poroelasticmodel. The heat transfer between the rock and fluid is modelled by using the conductive heat transferwithin the reservoir rock and convective heat transfer in discrete fractures. The thermal stress changesare included in the model to be studied by using roughness induced shear displacement principle in aporo-thermo-elastic environment. The fracture aperture changes are estimated by using an analyticalmodel based on the distributed dislocation technique. The roughness of fracture surfaces is used in thecalculation of residual fracture aperture. The presented approach is used to study the potential ofpermeability enhancement for Habanero geothermal reservoir at a depth of 3600 m. The result show thatthe increasing in tensile effective stress tend to increase the fracture aperture within the zone of *** increasing in fracture aperture led to significant changes in pressure distribution (decrease inimpedance) and hence, increase in the flow rate.

关键词： Fractured reservoirs Finite element Permeability tensor Fracture aperture Tensile stress Fractal density and dimension

ASTER Analysis for Locating REE-Bearing Granites in Arid Regions:Example from the Arabian Shield

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Journal of Earth Science 2022年第5期33卷 1114-1123页

作者： reda Amer Timothy M.Kusky Department of Earth and Space Sciences Lamar UniversityBeaumontTX77710USA State Key Laboratory of Geological Processes and Mineral Resources Center for Global TectonicsSchool of Earth SciencesBadong National Observatory and Research Station for GeohazardsChina University of GeosciencesWuhan430074China

The world’s increasing demand for rare earth elements(REEs)highlights the potential for using new multispectral remote sensing techniques to define new exploration targets in arid regions,such as the Kingdom of Saudi Arabia(KSA),Egypt,and regions of central and western *** REEs cannot be detected by satellite multispectral instruments,REEs-bearing alkaline granites can be identified on ASTER ***,we develop a new ASTER band ratio scheme to delineate mineralization-related features of the Ghurayyah REE-bearing peralkaline granite in the northwestern *** Ghurayyah peralkaline stock is located at the intersection of a NW striking segment of the Najd-fault system,and an E-W striking *** is surrounded to the north and west by metavolcanics,from east by the Jabal Dabbagh alkali granite,and from the south by *** mineralogical composition of granitic rocks resulted in spectral variation and causes absorption features at different wavelengths in the shortwave infrared(SWIR).The newly developed band ratios were constructed from(b6+b8)/(b6–b8)in red;(b6+b8)/b4 in green,and(b7–b9)/(b7+b9)in blue,enabling the discrimination between the Ghurayyah REE-bearing peralkaline granite,Jabal Dabbagh alkali granite,monzogranite,and *** work will be carried out to perform higher-resolution drone-based hyperspectral imaging for new high-resolution mapping and evaluate the existing REE deposits,emphasizing field spectral measurements to identify the spectral reflectance of REEs mineralized zones and the absorption features of monazite,columbite-tantalite,and aeschynite-(Y),coupled with rock sampling for petrographical,spectral,and geochemical *** methods have great potential for locating REEs-bearing peralkaline granites in the Arabian shield and elsewhere,such as arid portions of central and western China and adjacent regions.

关键词： remote sensing multispectral imaging rare earth elements Arabian Shield mineral exploration

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

Blockchain with Explainable Artificial Intelligence Driven Intrusion Detection for Clustered IoT Driven Ubiquitous Computing System

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Computer Systems Science & Engineering 2023年第9期46卷 2917-2932页

作者： reda Salama Mahmoud Ragab Information Technology Department Faculty of Computing and Information TechnologyKing Abdulaziz UniversityJeddah 21589Saudi Arabia Department of Mathematics Faculty of ScienceAl-Azhar UniversityNaser City11884CairoEgypt

In the Internet of Things(IoT)based system,the multi-level client’s requirements can be fulfilled by incorporating communication technologies with distributed homogeneous networks called ubiquitous computing systems(UCS).The UCS necessitates heterogeneity,management level,and data transmission for distributed ***,security remains a major issue in the IoT-driven ***,energy-limited IoT devices need an effective clustering strategy for optimal energy *** recent developments of explainable artificial intelligence(XAI)concepts can be employed to effectively design intrusion detection systems(IDS)for accomplishing security in *** this view,this study designs a novel Blockchain with Explainable Artificial Intelligence Driven Intrusion Detection for IoT Driven Ubiquitous Computing System(BXAI-IDCUCS)*** major intention of the BXAI-IDCUCS model is to accomplish energy efficacy and security in the IoT *** BXAI-IDCUCS model initially clusters the IoT nodes using an energy-aware duck swarm optimization(EADSO)algorithm to accomplish ***,deep neural network(DNN)is employed for detecting and classifying intrusions in the IoT ***,blockchain technology is exploited for secure inter-cluster data transmission *** ensure the productive performance of the BXAI-IDCUCS model,a comprehensive experimentation study is applied,and the outcomes are assessed under different *** comparison study emphasized the superiority of the BXAI-IDCUCS model over the current state-of-the-art approaches with a packet delivery ratio of 99.29%,a packet loss rate of 0.71%,a throughput of 92.95 Mbps,energy consumption of 0.0891 mJ,a lifetime of 3529 rounds,and accuracy of 99.38%.

关键词： Blockchain internet of things ubiquitous computing explainable artificial intelligence clustering deep learning

A Transfer Learning-Enabled Optimized Extreme Deep Learning Paradigm for Diagnosis of COVID-19

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Computers, Materials & Continua 2022年第1期70卷 1381-1399页

作者： Ahmed reda Sherif Barakat Amira Rezk Department of Information System Faculty of Computer and Information ScienceMansoura UniversityMansouraEgypt

Many respiratory infections around the world have been caused by ***-19 is one of the most serious coronaviruses due to its rapid spread between people and the lowest survival *** is a high need for computer-assisted diagnostics(CAD)in the area of artificial intelligence to help doctors and radiologists identify COVID-19 patients in cloud *** learning(ML)has been used to examine chest X-ray *** this paper,a new transfer learning-based optimized extreme deep learning paradigm is proposed to identify the chest X-ray picture into three classes,a pneumonia patient,a COVID-19 patient,or a normal ***,three different pre-trainedConvolutionalNeuralNetwork(CNN)models(resnet18,resnet25,densenet201)are employed for deep feature ***,each feature vector is passed through the binary Butterfly optimization algorithm(bBOA)to reduce the redundant features and extract the most representative ones,and enhance the performance of the CNN *** selective features are then passed to an improved Extreme learning machine(ELM)using a BOA to classify the chest X-ray *** proposed paradigm achieves a 99.48%accuracy in detecting covid-19 cases.

关键词： Butterfly optimization algorithm(BOA) covid-19 chest X-ray images convolutional neural network(CNN) extreme learning machine(ELM) feature selection

Temperature-dependent barrier height inhomogeneities in PTB7:PC71BM-based organic solar cells

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Chinese Physics B 2020年第9期29卷 609-614页

作者： Brahim Ait Ali reda Moubah Abdelkader Boulezhar Hassan Lassri LERDyS Faculty of Science Ain ChockHassan II University of CasablancaMorocco LPMMAT Faculty of Science Ain ChockHassan II University of CasablancaMorocco

We report on the temperature-dependent Schottky barrier in organic solar cells based on PTB7:*** ideality factor is found to increase with temperature decreasing,which is explained by a model in which the solar cell is taken as Schottky barrier ***,the dark current in the device originates from the thermally emitted electrons across the Schottky *** fittings obtained with the thermal emission theory are systematically studied at different *** is concluded that the blend/Ca/Al interface presents great inhomogeneity,which can be described by 2 sets of Gaussian distributions with large zero bias standard *** the decrease of temperature,electrons favor going across the Schottky barrier patches with lower barrier height and as a consequence the ideally factor significantly increases at low temperature.

关键词： organic materials photovoltaics Schottky barrier barrier height

Teaching Syntactic Relations:A Cognitive Semiotic Perspective

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Language and Semiotic Studies 2017年第2期3卷 1-21页

作者： Ghsoon reda Yanbu University College

This paper suggests a theoretical model for teaching syntactic relations to foreign students of English Linguistics using insights from Cognitive Grammar as developed in Langacker(e.g.1987,1991,1999) and elaborated on in Radden and Dirven(2007). The model deals with syntactic relations as participants in a prototypically structured network of events, radiating out from the experiential action chain schema(a skeletal concept of force dynamics involved in the interaction between entities)(see Langacker, 1999). This involves dealing with syntactic relations as meaning-making tools that collaborate with the verb in a regular manner manipulating the prototypical schema. The aim is to draw attention to the need to add a cognitive semiotic dimension to the teaching of sentence structure. Such a dimension exposes learners to the cognitive factors behind grammatical meaning making and may, therefore, result in a better understanding of language structure and use on the part of learners who can become English language teachers.

关键词： action chain schema Cognitive Grammar figure-ground perception event schemas syntactic relations