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Interactive data styling and multifocal visualization for a multigrid web-based Digital Earth

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International Journal of Digital Earth 2021年第3期14卷 288-310页

作者： m.J.sherlock m.Hasan F.F.samavati Department of Computer science University of CalgaryCalgaryCanada

Globe-based Digital Earth(DE)is a promising system that uses 3D models of the Earth for integration,organization,processing,and visualization of vast multiscale geospatial *** growing size and scale of geospatial datasets present significant obstacles to interactive viewing and meaningful visualizations of these DE *** address these challenges,we present a novel web-based multiresolution DE system using a hierarchical discretization of the globe on both server and client *** presented web-based system makes use of a novel data encoding technique for rendering large multiscale geospatial datasets,with the additional capability of displaying multiple simultaneous *** the data needed for the current views and scales are encoded and *** leverage the power of GPU acceleration on the client-side to perform real-time data rendering and dynamic *** rendering of multiple views allows us to support multilevel focus+context visualization,an effective approach to navigate through large multiscale global *** client–server interaction as well as the data encoding,rendering,styling,and visualization techniques utilized by our presented system contribute toward making DE more accessible and informative.

关键词： Digital Earth Discrete Global Grid system data integration data fusion multilevel focus+context visualization spatial resolution context awareness

Heat Convection Between Two Confocal Elliptic Tubes Placed at Different Orientations

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Advances in Applied mathematics and mechanics 2009年第5期1卷 639-663页

作者： F.m.mahfouz H.m.Badr Department of mechanical Engineering University of Engineering&TechnologyTaxilaPakistan Department of mechanical Engineering King Fahd University of Petroleum&MineralsKFUPM Box#322DhahranSaudi Arabia

In this paper,transient and steady natural convection heat transfer in an elliptical annulus has been *** annulus occupies the space between two horizontal concentric tubes of elliptic *** resulting velocity and thermal fields are predicted at different annulus orientations assuming isothermal *** full governing equations of mass,momentum and energy are solved numerically using the Fourier spectral *** heat convection process between the two tubes depends on Rayleigh number,Prandtl number,angle of inclination of tube axes and the geometry and dimensions of both *** Prandtl number and inner tube axis ratio are fixed at 0.7 and 0.5,*** problem is solved for the two Rayleigh numbers of 104 and 105 considering a ratio between the two major axes up to 3 while the angle of orientation of the minor axes varies from 0 to 90◦.The results for local and average Nusselt numbers are obtained and discussed together with the details of both flow and thermal *** isothermal heating conditions,the study has shown an optimum value for major axes ratio that minimizes the rate of heat transfer between the two *** important aspect of this paper is to prove the successful use of the Fourier spectral method in solving confined flow and heat convection problems.

关键词： Heat convection Elliptic tubes Fourier spectral methods Rayleigh number Prandtle number

A multi-Factor Authentication-Based Framework for Identity management in Cloud Applications

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Computers, materials & Continua 2022年第5期71卷 3193-3209页

作者： Wael said Elsayed mostafa m.m.Hassan Ayman mohamed mostafa Faculty of Computers and Informatics Zagazig UniversityZagazig44519Egypt College of Computer and Information sciences Jouf UniversitySakaka72314Saudi Arabia

User’s data is considered as a vital asset of several *** data to the cloud computing is not an easy decision for any organization due to the privacy and security *** providers must ensure that both data and applications that will be stored on the cloud should be protected in a secure *** data stored on the public cloud will be vulnerable to outside and inside *** paper provides interactive multi-layer authentication frameworks for securing user identities on the *** access control policies are applied for verifying users on the cloud.A security mechanism is applied to the cloud application that includes user registration,granting user privileges,and generating user authentication *** intrusion detection system is embedded to the security mechanism to detect malicious *** multi factor authentication,intrusion detection,and access control techniques can be used for ensuring the identity of the ***,encryption techniques are used for protecting the data from being *** results are carried out to verify the accuracy and efficiency of the proposed frameworks and *** results recorded high detection rate with low false positive alarms.

关键词： Cloud computing service providers multi-layer authentication frameworks and access control

Device and circuit analysis of a sub 20 nm double gate mOsFET with gate stack using a look-up-table-based approach

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Journal of semiconductors 2017年第12期38卷 37-41页

作者： s Chakraborty A Dasgupta R Das m Kar A Kundu C K sarkar Department of Electronics and Communications Engineering Heritage Institute of Technology Kolkata 700107India Nano Device simulation Laboratory Department of Electronics and Telecommunication EngineeringJadavpur UniversityKolkata 700032India

In this paper, we explore the possibility of mapping devices designed in TCAD environment to its modeled version developed in cadence virtuoso environment using a look-up table （LUT） approach. Circuit simu- lation of newly designed devices in TCAD environment is a very slow and tedious process involving complex scripting. Hence, the LUT based modeling approach has been proposed as a faster and easier alternative in ca- dence environment. The LUTs are prepared by extracting data from the device characteristics obtained from device simulation in TCAD. A comparative study is shown between the TCAD simulation and the LUT-based alternative to showcase the accuracy of modeled devices. Finally the look-up table approach is used to evaluate the perform- ance of circuits implemented using 14 nm nmOsFET.

关键词： 14 nm double gate mOsFET look-up table VerilogA

Effects of Variable Thermal Conductivity and Non-linear Thermal Radiation Past an Eyring Powell Nanofluid Flow with Chemical Reaction

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Communications in Theoretical Physics 2017年第6期67卷 723-731页

作者： m.Ramzan m.Bilal shamsa Kanwal Jae Dong Chung Department of Computer science Bahria UniversityIslamabad Campus Department of mathematics Faculty of ComputingCapital University of Science and Technology Department of mathematical sciences Fatima Jinnah Women University Department of mechanical Engineering Sejong University

Present analysis discusses the boundary layer flow of Eyring Powell nanofluid past a constantly moving surface under the influence of nonlinear thermal radiation. Heat and mass transfer mechanisms are examined under the physically suitable convective boundary condition. Effects of variable thermal conductivity and chemical reaction are also considered. series solutions of all involved distributions using Homotopy Analysis method(HAm) are *** of dominating embedded flow parameters are discussed through graphical illustrations. It is observed that thermal radiation parameter shows increasing tendency in relation to temperature profile. However, chemical reaction parameter exhibits decreasing behavior versus concentration distribution.

关键词： Eyring Powell nanofluid nonlinear thermal radiation convective boundary condition variable thermal conductivity chemical reaction

Origin and geochemistry of Pan-African granitoid rocks in the Gabal Um shomer area,southwestern sinai,Egypt

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Chinese Journal Of Geochemistry 2009年第2期28卷 125-135页

作者： E1-Tokhi m.m. musallum A. Amin B.m. Geology Department College of ScienceUnited Arab Emirates UniversityUnited Arab Emirates

Geological, petrological and geochemical studies indicated that there are two distinct types of granitoid rocks: older quartz diorites to granodiorite assemblage and younger granitoids, the latter occurring in two phases. The older granitoids have a meta-aluminous chemistry and a calc-alkaline character, with high mgO, Fe2O3, TiO2, CaO, P2O5, sr and low siO2, K2O, and Rb. Their major and trace elements data, together with low 87sr/ 86sr ratios (0.7029±0.0008) are indicative of I-type affinities. The second- and third-phase granitoids range from calc-alkaline to alkaline, respectively. The second-phase granitoids have a peraluminous chemistry and high sr, Ba, CaO, mgO, Al2O3 and Ti2O and low siO2, K2O, Nb, Y and Rb relative to the third-phase granitoids. The corundum normative nature and field observations suggested that it was formed by partial melting of the lower crust. The third-phase granitoids are alkaline in nature and characterized by higher siO2, Rb, Y, Nb and lower mgO, sr and Ba values than the younger granitoids (phase Ⅱ). They are A-type granitoids which were generated from below or within the existing continental crust.

关键词：花岗岩类岩石地球化学西奈半岛过铝质花岗岩起源西南埃及石英闪长岩

Integrated Use of Organic and Bio-fertilizers to Improve Yield and Fruit Quality of Olives Grown in Low Fertility sandy soil in an Arid Environment

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Phyton-International Journal of Experimental Botany 2023年第6期92卷 1813-1829页

作者： Bassam F.Alowaiesh m.m.Gad mohamed saleh m.Ali Biology Department College of ScienceJouf UniversitySakaka72341Saudi Arabia Horticulture Department Faculty of AgricultureZagazig UniversityZagazig44511Egypt Horticulture Department (pomology)Faculty of AgricultureSuez Canal UniversityIsmailia41522Egypt

Olive productivity should be improved through stimulating nutrition,particularly under poor fertility ***,the objective of this study was to assess the efficacy of applying organic and bio-fertilizers on the physiological growth,yield and fruit quality of olive trees under newly reclaimed poor-fertility sandy soil in an arid *** a field experiment carried out at El-Qantara,North sinai,Egypt over two consecutive seasons(2019-2020 and 2020-2021),olive Kalamata trees were evaluated under three organic fertilizer treatments alone or in combination with three bio-fertilizers *** fertilizer was applied as goat manure(16.8 kg/tree/year),or olive pomace(8.5 kg/tree/year)in mid-December of each season *** *** bio-fertilizers were applied as N-fixing bacteria(150 g/tree)was inculated in early march of each season,or amino acid mixture(1.5%)was applied three times,at 70%of full bloom,21 days after full bloom,and a month later in comparison to a non-fertilized trees(control).The cultivar used was Kalamata,a dual-purpose cultivar for oil and table olives whose value increases when processed as table *** results indicated that the goat manure followed by olive pomace significantly enhanced photosynthetic pigments(chlorophyll a,b,and carotenoids),leaf mineral contents(N,P,K,Ca,mg and Fe),tree canopy volume,number of flowers per inflorescence,number of inflorescences per shoot,initial fruit set,fruit *** fruit quality,fruit length and width,fruit weight,and total fruit yield was increased compared to the non-fertilized ***,The bio-fertilizer N-fixing bacteria followed by the amino acid mixture significantly improved all of the aforementioned ***,it is recommended,both environmentally and economically to utilize organic and bio-fertizers,particularly goat manure combined with N-fixing bacteria,in low-fertility soil to sustain olive production as well as reducing mineral ferti

关键词： Organic and bio-fertilizers olives kalamata vegetative growth leaf mineral contents fruit quality

Historical Arabic Images Classification and Retrieval Using siamese Deep Learning model

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Computers, materials & Continua 2022年第7期72卷 2109-2125页

作者： manal m.Khayyat Lamiaa A.Elrefaei mashael m.Khayyat Computer science Department Umm Al-Qura UniversityMakkahSaudi Arabia Computer science Department King Abdulaziz UniversityJeddahSaudi Arabia Electrical Engineering Department Faculty of Engineering at ShoubraBenha UniversityCairoEgypt Department of Information systems and Technology College of Computer Science and EngineeringUniversity of JeddahJeddahSaudi Arabia

Classifying the visual features in images to retrieve a specific image is a significant problem within the computer vision field especially when dealing with historical faded colored ***,there were lots of efforts trying to automate the classification operation and retrieve similar images *** reach this goal,we developed a VGG19 deep convolutional neural network to extract the visual features from the images ***,the distances among the extracted features vectors are measured and a similarity score is generated using a siamese deep neural *** siamese model built and trained at first from scratch but,it didn’t generated high evaluation ***,we re-built it from VGG19 pre-trained deep learning model to generate higher evaluation ***,three different distance metrics combined with the sigmoid activation function are experimented looking for the most accurate method formeasuring the similarities among the retrieved *** that the highest evaluation parameters generated using the Cosine distance ***,the Graphics Processing Unit(GPU)utilized to run the code instead of running it on the Central Processing Unit(CPU).This step optimized the execution further since it expedited both the training and the retrieval time *** extensive experimentation,we reached satisfactory solution recording 0.98 and 0.99 F-score for the classification and for the retrieval,respectively.

关键词： Visual features vectors deep learning models distance methods similar image retrieval

Use of a Laser/TIG Combination for surface modification of Ti-6Al-4V Alloy

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Journal of materials science & Technology 2001年第2期17卷 237-239页

作者： m.Labudovic and R.Kovacevic southern methodist University, Dept. of mechanical Engineering, Dallas, Texas, U.s.A. Dept. of mech. Eng. Southern Methodist Univ. Dallas United States

The surface modification of materials such as Ti-6Al-4V is necessary to improve their wear resistant properties for use in tribological applications. In this paper it is shown that a laser with low power and tungsten inert gas (TIG) can be combined together for surface modification of Ti-6Al-4V alloy, and when performed in a controlled atmosphere of pure nitrogen or a mixture of nitrogen and argon, can produce a wear-resistant surface alloy. Compared with laser processing, a cheaper surface modification process has been developed involving a shorter processing time, which is free of stringent requirements such as a vacuum system.

关键词： Ti TIG Use of a Laser/TIG Combination for surface modification of Ti-6Al-4V Alloy Al