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Global Reference Grids for Big Earth Data

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Big Earth Data 2022年第3期6卷 251-255页

作者： Robert G.Gibb Matthew B.J.Purss zoheir sabeur Peter Strobl Tengteng Qu Manaaki Whenua–Landcare Research Palmerston NorthNew Zealand Pangaea Innovations Pty.Ltd CanberraAustralia Department of Computing and Informatics Talbot CampusUniversity of BournemouthBournemouthUK European Commission Joint Research Centre(JRC)IspraItaly College of Engineering Peking UniversityBeijingChina

The emerging field of Discrete Global Grid Systems(DGGS)provides a way to organise,store and analyse spatio-temporal data at multiple resolutions and scales(from near global scales down to microns).DGGS partition the entire planet into a discrete hierarchy of global tessellations of progressively finer resolution zones(or cells).Data integration,decomposition and aggregation are optimised by assigning a unique spatio-temporal identifier to each *** identifiers are encodings of both the zone’s location and its *** a result,complex multi-dimensional,multi-resolution spatio-temporal operations are simplified into sets of 1D array and filter operations.

关键词： operations simplified partition

Assessment of converting approach to efficient design of micro-turboprop engines

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Chinese Journal of Aeronautics 2020年第2期33卷 572-588页

作者： Hamed GOLCHIN Fathollah OMMI zoheir SABOOHI Department of Mechanical Engineering Tarbiat Modares UniversityTehran 14115-111Iran Aerospace Research Institute(ARI) Ministry of ScienceResearchand TechnologyTehran 14115-111Iran

The design,manufacture and experiment of a shaft power unit for converting a microturbojet engine to a micro-turboprop in the class of less than 20 kW with the aim of obtaining maximum shaft power were described in this *** this purpose,a Wren 100 micro-turbojet engine was used as the gas generator,and the specifications of its outflow were *** optimal configuration of the inter-stage diffuser,which was an annular S-type diffuser,was selected based on its small total pressure drop and outlet flow *** power turbine was a single stage axial turbine that was designed based on the fixed nozzle angle assumption without any taper or twist in its *** turbine rotor was a bladed disk(Blisk)in which its unique blade profiles were designed based on the Wilson ***,the shaft power unit was completed by designing and manufacturing an exhaust complex and ***,the micro-turboprop engine was tested with an overloading *** results show a significant increase in the extracted power,an acceptable efficiency of the power turbine,and a significant reduction in the Specific Fuel Consumption(SFC)compared to other engines that use similar gas generators.

关键词： Axial turbine Blisk Gas generators Micro-turboprop Power unit

Controls on lode gold mineralization,Romite deposit,South Eastern Desert,Egypt

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Geoscience Frontiers 2012年第5期3卷 571-585页

作者： Basem A.zoheir Department of Geology

Field and remote sensing studies reveal that Au-bearing quartz carbonate lodes in Romite deposit, in the extreme South Eastern Desert of Egypt, are controlled by NNE-striking shear zones that splay from the ca. 660--550 Ma Hamisana Zone. Quartz in releasing bends with sinistral shear geometry and abundant boudinaged quartz-carbonate lodes with serrate ribboned fabrics suggest vein formation throughout a transpressive wrench system. Ubiquitous hydrothermal quartz, carbonate, and subordinate chlorite and sericite within the shear zones and as slivers in veins, indicate that gold deposition and hydro- thermal alteration occurred under greenschist facies conditions. The AI （IV） in chlorite indicates a forma- tion temperature of - 300 ℃, comparable with temperatures estimated from arsenopyrite composition for grains intimately associated with gold in quartz veins. The new geological and geochemical data indicate that splays off the Hamisana Zone are potential gold exploration targets. Quartz veins along the high order （2nd or 3rd） structures of this crustal-scale shear zone are favorable targets. In the Romite deposit and in surrounding areas, a Au-As-Cu-Sb-Co-Zn geochemical signature characterizes mineralized zones, and particularly rock chips with 〉 1000 ppm As and high contents of Cu, Zn, and Co target the better mineralized areas. The carbonate δ13CpDB and δ18OsMow isotope signatures preclude an organic source of the ore fluid, but metamorphic and magmatic sources are still valid candidates. The intense deformation and lack of mag- matism in the deposit area argue for metamorphic dewatering of greenstone rocks as the most likely fluid source. The narrow ranges of δ13C （-4.6‰ to -3.1‰） and 6180 （11.9‰- 13.7‰） in carbonate minerals in lodes imply a corresponding uniformity to the ambient temperature and δ13CCO2 （δ13C∑C） of the ore *** calculated δ18OH2O values of 6‰-7.9‰for ore fluids, based on 6180 values of vein quartz further suggest a likely metamorphic o

关键词： Romite gold deposit Orogenic lodes Hamisana Zone Stable isotopes Egypt

Effect of pressure and space between electrodes on the deposition of SiN_(x)H_(y)films in a capacitively coupled plasma reactor

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Chinese Physics B 2021年第5期30卷 507-512页

作者： Meryem Grari CifAllah zoheir Yasser Yousfi Abdelhak Benbrik University Mohamed First Department of PhysicsLETSER LaboratoryOujdaMorocco University Mohamed First Department of MathematicsLANO LaboratoryOujdaMorocco

The fluid model,also called the macroscopic model,is commonly used to simulate low temperature and low pressure radiofrequency plasma *** varying the parameters of the model,numerical simulation allows us to study several cases,providing us the physico-chemical information that is often difficult to obtain *** this work,using the fluid model,we employ numerical simulation to show the effect of pressure and space between the reactor electrodes on the fundamental properties of silicon plasma diluted with ammonia and *** results show the evolution of the fundamental characteristics of the plasma discharge as a function of the variation of the pressure and the distance between the *** examining the pressure-distance product in a range between 0.3 Torr 2.7 cm and 0.7 Torr 4 cm,we have determined the optimal pressure-distance product that allows better deposition of hydrogenated silicon nitride(SiN_(x)H_(y))films which is 0.7 Torr 2.7 cm.

关键词： fluid model numerical simulation SiN_(x)H_(y) capacitively coupled plasma reactor

Numerical Study of Natural Convective Heat Transfer in an Air Filled Square Cavity Heated from Below and Symmetrically Cooled from the Sides with a Partition in the Hot Wall

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Fluid Dynamics & Materials Processing 2023年第2期19卷 513-539页

作者： Farah Zemani-Kaci Amina sabeur-Bendhina Laboratoire des Sciences et Ingénierie Maritimes Facultéde Génie MécaniqueUSTO-MBBP 1505 El M’naouerOran31000Algérie

A two-dimensional numerical study of laminar natural convection in a square enclosure filled with air with a wall partially heated on the bottom is *** heat source is located on the lower wall with different heated widths varied from 20 to 80%(ε=0.2–0.8)of the total width of the lower wall and different heights h=H/4 and H/2 of the *** effect of the partition height on the main system dynamics is investigated through solution of the two-dimensional Navier-Stokes equations and the energy equation by means of a finite volume method based on the SIMPLE *** influence of the Rayleigh number(Ra=10^(3) to 10^(6))and the hot wall length is also *** is shown that the average Nusselt number grows whenεincreases and when h *** a given value ofεand h,the average Nusselt number increases as Ra *** is concluded that the partition height causes a decrease in the average Nusselt number.

关键词： Natural convection square enclosure heat source partial partition nusselt number

Turbulent Double-Diffusive Natural Convection and Entropy Generation within an Inclined Square Cavity

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Fluid Dynamics & Materials Processing 2022年第6期18卷 1619-1629页

作者： Khaled Said Ahmed Ouadha Amina sabeur Laboratoire des Sciences et Ingénierie Maritimes Facultéde Génie MécaniqueUniversitédes Sciences et de la Technologie Mohamed BOUDIAF d’OranOran El-MnouarAlgérie

The present study deals with double-diffusive convection within a two-dimensional inclined cavity filled with an air-CO_(2) binary gas *** left and the right vertical walls are differentially heated and subjected to different locations of(CO_(2))contaminants to allow for the variation of the buoyancy strength(N).However,the horizontal walls are assumed *** simulations are conducted using the finite volume method to solve the conservation equations of continuity,momentum,energy,and species *** agreement with other numerical results in the literature is *** effect of multiple parameters,namely,buoyancy ratio(N),thermal Rayleigh number(Ra),and inclination angle(α)on entropy generation rate is analyzed and discussed in the postprocessing stage,while considering both laminar and turbulent flow *** computations reveal that these parameters considerably affect both the heat and mass transfer performances of the system.

关键词： CFD entropy generation double diffusive convection inclination angle CO_(2) turbulent regime

Numerical Simulation of Turbulent Diffusion Flames of a Biogas Enriched with Hydrogen

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Fluid Dynamics & Materials Processing 2024年第1期20卷 79-96页

作者： Naima Krarraz Amina sabeur Khadidja Safer Ahmed Ouadha Laboratoire des Science et Ingénierie Maritimes Facultéde Génie MécaniqueUniversitédes Sciences et de la Technologie d’Oran Mohamed BoudiafOranAlgérie Laboratoire des Carburants Gazeux et de l’Environnement Facultéde Génie MécaniqueUniversitédes Sciences et de la Laboratoire des Carburants Gazeux et de l’Environneme

Any biogas produced by the anaerobic fermentation of organic materials has the advantage of being an environmentally friendly ***,the relatively low calorific value of such gases makes their effective utilization in practical applications relatively *** present study considers the addition of hydrogen as a potential solution to mitigate this *** particular,the properties of turbulent diffusion jet flames and the related pollutant emissions are investigated numerically for different operating *** related numerical simulations are conducted by solving the RANS equations in the frame of the Reynolds Stress Model in combination with the flamelet *** effects are also taken into account and the combustion kinetics are described via the GRI-Mech 3.0 reaction *** considered hydrogen fuel enrichment spans the range from 0%to 50%in terms of *** varies between 1 and 10 *** results show that both hydrogen addition and pressure increase lead to an improvement in terms of mixing quality and have a significant effect on flame temperature and *** also reduce CO_(2) emissions but increase NOx *** NO is shown to be the predominant NO formation mechanism.

关键词： Biogas hydrogen diffusion flame turbulence NO formation route pressure

Geochemical and geochronological characteristics of the Um Rus granite intrusion and associated gold deposit,Eastern Desert,Egypt

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Geoscience Frontiers 2020年第1期11卷 325-345页

作者： Basem zoheir Richard Goldfarb Astrid Holzheid Hassan Helmy Ahmed El Sheikh Department of Geology Faculty of ScienceBenha University13518BenhaEgypt Institute of Geosciences University of KielLudewig-Meyn Str.1024118KielGermany State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences(Beijing)Beijing100083China Department of Geology Faculty of ScienceMinia University61519MiniaEgypt Department of Geology Faculty of ScienceSohag UniversityEgypt

The Um Rus tonalite-granodiorite intrusion(~6 km2)occurs at the eastern end of the Neoproterozoic,ENE-trending Wadi Muba rak shear belt in the Central Eastern Desert of ***-bearing quartz veins hosted by the Um Rus intrusion were mined intermittently,and initially by the ancient Egyptians and until the early 1900 *** relationship between the gold mineralization,host intrusion,and regional structures has always been *** present new geochemical and geochronological data that help to define the tectonic environment and age of the Um Rus *** addition,field studies are integrated with EPMA and LA-ICP-MS data for gold-associated sulfides to better understand the formation and distribution of gold *** bulk-rock geochemical data of fresh host rocks indicate a calc-alkaline,metaluminous to mildly peraluminous,I-type granite *** trace element composition reflects a tectonic setting intermediate between subduction-related and within-plate environments,presumably transitional between syn-and post-collisional *** crystallization age of the Um Rus intrusion was determined by in situ SHRIMP 206 Pb/238 U and 207Pb/235U measurements on accessory monazite *** resultant monazite U-Pb weighted mean age(643±9 Ma;MSWD 1.8)roughly overlaps existing geochronological data for similar granitic intrusions that are confined to major shear systems and are locally associated with gold mineralization in the Central Eastrn Desert(e.g.,Fawakhir and Hangaliya).This age is also consistent with magmatism recognized as concomitant to transpressional tectonics(D2:~650 Ma)during the evolution of the Wadi Mubark *** of the gold-bearing quartz veins in NNE-SSW and N-S striking fault segments was likely linked to the change from transpressional to transtensional tectonics and terrane exhumation(D3:620-580 Ma).The development of N-S throughgoing fault arrays and dike swarms(~595 Ma)led to heterogeneous deformation and recrystallizat

关键词： Um Rus intrusion Whole-rock geochemistry SHRIMP U-Pb monazite dating Gold mineralization LA-ICP-MS data of pyrite and arsenopyrite

Impact of the Inlet Flow Angle and Outlet Placement on the Indoor Air Quality

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Fluid Dynamics & Materials Processing 2024年第11期20卷 2603-2616页

作者： Ikram Mostefa Tounsi Mustapha Boussoufi Amina sabeur Mohammed El Ganaoui Laboratoire des Sciences et Ingénierie Maritimes Facultéde Génie Mécanique.Universitédes Sciences et de la Technologie d’Oran Mohammed BoudiafBP 1505 El M’NaouerOran31000Algérie Laboratoire LERMAB IUT Longwy Universitéde LorraineNancy54000France

This study aims to optimize the influence of the inlet inclination angle on the Indoor Air Quality(IAQ),heat,and temperature distribution in mixed convection within a two-dimensional square cavityfilled with an air-CO_(2)*** air-CO_(2)mixture enters the cavity through two inlet openings positioned at the top wall,which is set at the ambient temperature(TC).Three values of the Reynolds numbers,ranging from 1000 to 2000,are considered,while the Prandtl number is kept constant(Pr=0.71).The temperature distribution and streamlines are shown for Rayleigh number(Ra)equal to 104,three inlet inclination anglesϕ(0,π/6 andπ/4)and three CO_(2)concentrations values(1500,2500,3500 ppm)applied at both hot vertical walls(maintained at a constant temperature TH).Afinite volume method is used under the assumption of two-dimensional laminarflow to solve the NavierStokes and energy *** results indicate that inlet inclination angle has an impact on the indoor air quality(IAQ),which,in turn,affects the heat transfer distribution and thermal comfort within the cavity.

关键词： Mixed convection air-CO_(2) mixture inlet inclination angles laminarflow indoor air quality