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radiation effect on temperature distribution in three-dimensional Couette flow with suction or injection

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Applied Mathematics and Mechanics(English Edition) 2007年第3期28卷 309-316页

作者： Bhupendra Kumar Sharma Mamta Agarwal r.C.Chaudhary Department of Mathematics University of RajasthanJaipur-302004India

A theoretical analysis of three-dimensional Couette flow with radiation effect on temperature distribution has been analysed, when the injection of the fluid at the lower stationary plate is a transverse sinusoidat one and its corresponding removal by constant suction through the upper porous plate is in uniform motion. Due to this type of injection velocity, the flow becomes three-dimensional. The effect of Prandtl number, radiation parameter and injection parameter on rate of heat transfer has been examined by the help of graphs. The Prandtl number has a much greater effect on *** distribution than the injection or radiation parameter.

关键词： Couette flow three-dimensional heat transfer radiation incompressible

Enhanced Trust Based Access Control for Multi-Cloud Environment

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Computers, Materials & Continua 2021年第12期69卷 3079-3093页

作者： N.r.rejin Paul D.Paul raj Technology PuduvoyalGummidipoondi601206India r M D Engineering College KavaraipettaiGummidipoondi601206India

Security is an essential part of the cloud *** ensuring the security of the data being communicated to and from the cloud server,a significant parameter called trust was ***-based security played a vital role in ensuring that the communication between cloud users and service providers remained unadulterated and *** most cloud-based data distribution environments,emphasis is placed on accepting trusted client users’requests,but the cloud servers’integrity is seldom *** paper designs a trust-based access control model based on user and server characteristics in a multi-cloud environment to address this *** proposed methodology consists of data encryption using Cyclic Shift Transposition Algorithm and trust-based access control *** this trust-based access control mechanism framework,trust values are assigned to cloud users using direct trust *** direct trust degree is estimated based on the following metrics:success and failure rate of interactions,service satisfaction index,and dishonesty *** addition to this,trust values are assigned to cloud servers based on the metrics:server load,service rejection rate,and service access *** role-Based Access control policy of each user is modified based on his trust *** the server fails to meet the minimum trust level,then another suitable server will be *** proposed system is found to outperform other existing systems in a multi-cloud environment.

关键词： Cloud computing trust access control cloud service provider cloud data user CSTA

Interpretation of tangential and radial pressure cells in and on sprayed concrete tunnel linings

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Underground Space 2021年第5期6卷 516-527页

作者： Benoit D.Jones Chris r.I.Clayton Inbye Engineering Limited Coventry CV12NPUK Department of Engineering University of SouthamptonSouthampton SO171BJUK

It is important to be able to measure stresses in tunnel linings to verify design assumptions and validate numerical *** sprayed concrete-lined tunnels,continuous monitoring of stresses from the time of spraying onwards is desirable,and this can only be achieved using pressure cells installed on and in the sprayed concrete *** there has been some success in using radial pressure cells between the ground and the lining,a method for obtaining reliable absolute values of stress from tangential pressure cells embedded in the sprayed concrete has not been *** paper describes numerical and experimental studies of the behavior of pressure cells for monitoring stresses in a sprayed concrete lining and describes an original methodology to achieve reliable *** particular,data from tangential pressure cells require careful interpretation,as they are sensitive to temperature,and this temperature sensitivity is found in parametric numerical analyses to vary as the stiffness of the concrete and its coefficient of thermal expansion evolve at early *** pressure cells are also sensitive to shrinkage strains in the concrete,and a methodology for removing this effect is *** the approach described in this paper,it is now possible to use pressure cells to measure absolute values of stresses in and on sprayed concrete tunnel linings from early age into the *** example of radial and tangential pressure cells installed in the Heathrow Terminal 4 concourse tunnel is used to illustrate the methodology.

关键词： Lining stresses Sprayed concrete Shotcrete Monitoring Pressure cells

Effect of Quantizing Magnetic Field on Cyclotron Energy and Cyclotron Effective Mass in Size Quantized Films with Non-Parabolic Energy Band

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Chinese Physics Letters 2007年第9期24卷 2639-2641页

作者： B.I.GULIYEV r.F.EMINBEYLI A. KOrKUT Yuzuncii Yll University Art and Science Faculty Physics Department 65080 Van Turkey

The Fermi energy, cyclotron energy and cyclotron effective mass of degenerate electron gas in a sizeoquantized semiconductor thin film with non-parabolic energy bands are studied. The influences of quantizing magnetic field on these quantities in two-band approximation of the Kane model are investigated. It is shown that the Fermi energy oscillates in a magnetic field. The period and positions of these oscillations are found as a function of film thickness and concentration of electrons. Cyclotron energy and cyclotron effective mass are investigated as a function of film thickness in detail The results obtained here are compared with experimental data on GaAs quantum wells.

关键词： coated conductor buffer layer self-epitaxy CeO2

Metabolic and Signaling Aspects Underpinning the regulation of Plant Carbon Nitrogen Interactions

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Molecular Plant 2010年第6期3卷 973-996页

作者： Adriano Nunes-Nesi Alisdair r. Fernie Mark Stitt Max Planck Institute for Molecular Plant Physiology Am M~hlenberg 1 14476 Potsdam-Golm Germany

In addition to light and water, CO2 and mineral elements are required for plant growth and development. Among these factors, nitrogen is critical, since it is needed to synthesize amino acids, which are the building elements of protein, nucleotides, chlorophyll, and numerous other metabolites and cellular components. Therefore, nitrogen is required by plants in higher quantities and this investment in nitrogen supports the use of CO2, water, and inorganic nitrogen to produce sugars, organic acids, and amino acids, the basic building blocks of biomass accumulation. This system is maintained by complex metabolic machinery, which is regulated at different levels according to environmental factors such as light, CO2, and nutrient availability. Plants integrate these signals via a signaling network, which involves metabolites as well as nutrient-sensing proteins. Due to its importance, much research effort has been expended to understand how carbon and nitrogen metabolism are integrated and regulated according to the rates of photosynthesis, photorespiration, and respiration. Thus, in this article, we both discuss recent advances in carbon/nitrogen metabolisms as well as sensing and signaling systems in illuminated leaves of C3-plants and provide a perspective of the type of experiments that are now required in order to take our understanding to a higher level.

关键词： Primary metabolism CN balance signaling.

Free vibration and critical speed of moderately thick rotating laminated composite conical shell using generalized differential quadrature method

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Applied Mathematics and Mechanics(English Edition) 2013年第4期34卷 437-456页

作者： K.DANESHJOU M.TALEBITOOTI r.TALEBITOOTI School of Mechanical Engineering Iran University of Science and Technology School of Automotive Engineering Iran University of Science and Technology

The generalized differential quadrature method （GDQM） is employed to con- sider the free vibration and critical speed of moderately thick rotating laminated compos- ite conical shells with different boundary conditions developed from the first-order shear deformation theory （FSDT）. The equations of motion are obtained applying Hamilton＇s concept, which contain the influence of the centrifugal force, the Coriolis acceleration, and the preliminary hoop stress. In addition, the axial load is applied to the conical shell as a ratio of the global critical buckling load. The governing partial differential equations are given in the expressions of five components of displacement related to the points ly- ing on the reference surface of the shell. Afterward, the governing differential equations are converted into a group of algebraic equations by using the GDQM. The outcomes are achieved considering the effects of stacking sequences, thickness of the shell, rotating velocities, half-vertex cone angle, and boundary conditions. Furthermore, the outcomes indicate that the rate of the convergence of frequencies is swift, and the numerical tech- nique is superior stable. Three comparisons between the selected outcomes and those of other research are accomplished, and excellent agreement is achieved.

关键词： generalized differential quadrature method (GDQM) natural frequency,rotating conical shell first-order shear deformation theory (FSDT) critical speed

High permittivity and low dielectric loss analysis of lead free Sr_(1-x)La_x(Ti_(0.5) Fe_(0.5))O_3

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Journal of Central South University 2013年第12期20卷 3363-3371页

作者： M.r.Shah A.K.M.Akther Hossain Department of Physics Primeasia University Department of Physics Bangladesh University of Engineering and Technology

The structural and electrical properties of lead free Srx-xLax（***.5）O3 （SLTFO） prepared by standard solid state reaction technique were studied. The X-ray diffraction analysis confirmed the formation of a single-phase cubic perovskite structure. The compositional dependence of lattice constant, density and microstructural studies show that they vary significantly with La3＋ content. when measured at 10 kHz, all the compositions of SLTFO at room temperature exhibit a high permittivity （about 104） and low dielectric loss （about 10-3）. SLTFO also display minimum dielectric loss within the lower and higher limits of frequency, indicating that the samples are of good quality. It is concluded from the calculated ac conductivity that the conduction is due to mixed polarons hopping. The complex impedance plot exhibits a tendency of forming a single semicircular arc for all compositions, which implies a dominance of grain boundary resistance on the impedance. Impedance parameters were determined by fitting the experimental data with Cole-Cole empirical formula. The results of the present experiment indicate that the lead free SLTFO materials with higher permittivity and lower dielectric loss have possible practical applications.

关键词： dielectric properties solid state reaction Sr titanate X-ray diffraction

Innate and adaptive immune responses that control lymph-borne viruses in the draining lymph node

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Cellular & Molecular Immunology 2024年第9期21卷 999-1007页

作者： Carolina r.Melo-Silva Luis J.Sigal Department of Microbiology and Immunology Thomas Jefferson UniversityBluemle Life Sciences Building Room 709233 South 10th StreetPhiladelphiaPA19107USA

The interstitial fluids in tissues are constantly drained into the lymph nodes(LNs)as lymph through afferent lymphatic vessels and from LNs into the blood through efferent *** are strategically positioned and have the appropriate cellular composition to serve as sites of adaptive immune initiation against invading ***,for lymph-borne viruses,which disseminate from the entry site to other tissues through the lymphatic system,immune cells in the draining LN(dLN)also play critical roles in curbing systemic viral dissemination during primary and secondary ***-borne viruses in tissues can be transported to dLNs as free virions in the lymph or within infected *** of the entry mechanism,infected myeloid antigen-presenting cells,including various subtypes of dendritic cells,inflammatory monocytes,and macrophages,play a critical role in initiating the innate immune response within the *** innate immune response involves cellular crosstalk between infected and bystander innate immune cells that ultimately produce type I interferons(IFN-Is)and other cytokines and recruit inflammatory monocytes and natural killer(NK)***-I and NK cell cytotoxicity can restrict systemic viral spread during primary infections and prevent serious ***,the memory CD8+T-cells that reside or rapidly migrate to the dLN can contribute to disease prevention during secondary viral *** review explores the intricate innate immune responses orchestrated within dLNs that contain primary viral infections and the role of memory CD8+T-cells following secondary infection or CD8+T-cell vaccination.

关键词： Virus infection lymph borne virus lymph node virus control innate immunity adaptive immunity dendritic cells Langerhans cells macrophages inflammatory monocytes natural killer cells CD8+T-cells

Optimal Artificial Intelligence Based Automated Skin Lesion Detection and Classification Model

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Computer Systems Science & Engineering 2023年第1期44卷 693-707页

作者： Kingsley A.Ogudo r.Surendran Osamah Ibrahim Khalaf Faculty of Engineering and the Built Environment Department of Electrical and Electronics Engineering TechnologyUniversity of JohannesburgJohannesburg2006South Africa Center for Artificial Intelligence and research(CAIr) Chennai Institute of TechnologyChennai600069India Al-Nahrain Nanorenewable Energy research Center Al-Nahrain UniversityBaghdad64074Iraq

Skin lesions have become a critical illness worldwide,and the earlier identification of skin lesions using dermoscopic images can raise the survival *** of the skin lesion from those dermoscopic images will be a tedious *** accuracy of the classification of skin lesions is improved by the use of deep learning ***,convolutional neural networks(CNN)have been established in this domain,and their techniques are extremely established for feature extraction,leading to enhanced *** this motivation,this study focuses on the design of artificial intelligence(AI)based solutions,particularly deep learning(DL)algorithms,to distinguish malignant skin lesions from benign lesions in dermoscopic *** study presents an automated skin lesion detection and classification technique utilizing optimized stacked sparse autoen-coder(OSSAE)based feature extractor with backpropagation neural network(BPNN),named the OSSAE-BPNN *** proposed technique contains a multi-level thresholding based segmentation technique for detecting the affected lesion *** addition,the OSSAE based feature extractor and BPNN based classifier are employed for skin lesion ***,the parameter tuning of the SSAE model is carried out by the use of sea gull optimization(SGO)*** showcase the enhanced outcomes of the OSSAE-BPNN model,a comprehensive experimental analysis is performed on the benchmark *** experimentalfindings demonstrated that the OSSAE-BPNN approach outper-formed other current strategies in terms of several assessment metrics.

关键词： Deep learning dermoscopic images intelligent models machine learning skin lesion