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deductive way of reasoning about the internet As level topology

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Chinese Physics B 2015年第11期24卷 633-642页

作者： dávid szabó Attila Korsi józsef Bíró András Gulyás High speed Networks Laboratory Budapest University of Technology and Economics MTA-BME Information systems Research Group Budapest University of Technology and Economics MTA-BME Future Internet Research Group Budapest University of Technology and Economics

Our current understanding about the As level topology of the Internet is based on measurements and inductive-type models which set up rules describing the behavior （node and edge dynamics） of the individual Ases and generalize the consequences of these individual actions for the complete As ecosystem using induction. In this paper we suggest a third, deductive approach in which we have premises for the whole As system and the consequences of these premises are determined through deductive reasoning. We show that such a deductive approach can give complementary insights into the topological properties of the As graph. While inductive models can mostly reflect high level statistics （e.g., degree distribution, clustering, diameter）, deductive reasoning can identify omnipresent subgraphs and peering likelihood. We also propose a model, called YEAs, incorporating our deductive analytical findings that produces topologies contain both traditional and novel metrics for the As level Internet.

关键词： internet topology complex network analysis model

Impact of systems modelling on agronomic research and adoption of new practices in smallholder agriculture

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journal of Integrative Agriculture 2015年第8期14卷 1478-1489页

作者： d j Connor H van Rees P s Carberry The University of Melbourne Crop Facts Mandurang South 3551 Australia Commonwealth scientific and Industrial Research Organization

An analysis of the impact of simulation modelling in three diverse crop-livestock improvement projects in Agricultural Research for development（AR4d） reveals benefits across a range of aspects including identification of objectives, design and implementation of experimental programs, effectiveness of participatory research with smallholder farmers, implementation of system change and scaling-out of *** planning change, farmers must consider complex interactions within both biophysical and socioeconomic aspects of their crop and animal production *** this, whole-farm models that include household models of food, workload and financial requirements have the most utility and *** analysis also proposes improvements in design and implementation of AR4 d projects to improve the utility of simulation modelling for securing positive agronomic and livestock outcomes and lasting legacies.

关键词： agricultural systems animal production crop production modelling research for development

Exopolysaccharide-Producing Plant Growth-Promoting Rhizobacteria Under salinity Condition

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Pedosphere 2011年第2期21卷 214-222页

作者： s.K.UPAdHYAY j.s.sINGH d.P.sINGH department of Environmental science Babasaheb Bhimrao Ambedker (Central) UniversityRaibarelly RoadLucknow-226025 (India)

salt-tolerant plant growth-promoting rhizobacteria （PGPR） can play an important role in alleviating soil salinity stress during plant growth and bacterial exopolysaccharide （EPs） can also help to mitigate salinity stress by reducing the content of Na＋ available for plant uptake. In this study, native bacterial strains of wheat rhizosphere in soils of Varanasi, India, were screened to identify the EPs-producing salt-tolerant rhizobacteria with plant growth-promoting traits. The various rhizobacteria strains were isolated and identified using 16s rdNA sequencing. The plant growth-promoting effect of inoculation of seedlings with these bacterial strains was evaluated under soil salinity conditions in a pot experiment. Eleven bacterial strains which initially showed tolerance up to 80 g L-1 NaC1 also exhibited an EPs-producing potential. The results suggested that the isolated bacterial strains demonstrated some of the plant growth-promoting traits such as phosphate solubilizing ability and production of auxin, proline, reducing sugars, and total soluble sugars. Furthermore, the inoculated wheat plants had an increased biomass compared to the unoinoculated plants.

关键词： NaCl plant uptake rhizosphere salt tolerance wheat

Prevalence of Gender-Based Violence among sex Workers in Bangui, Central African Republic (CAR)

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Accuracy details in realistic CFd modeling of an industrial centrifugal pump in direct and reverse modes

Advances in sexual Medicine（性医学进展） 2024年第2期 13页

作者： d.Mossoro-Kpinde Hermione s.C.diemer Henri R.Tende Nzengou Richard s.siki Francis j.d.d.Tekpa Bertrand

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journal of Thermal science 2010年第6期19卷 491-499页

作者： j.C. Páscoa F. j. silva j.s. Pinheiro d.j. Martins department of Electromechanical Engineering Center for Aerospace Sciences and Technology University of Beira Interior EFAFLU Bombas e Ventiladores s.A. R. S. Brás 269 Apartado 23 4494-909 Póvoa do Varzim Portugal

Numerical computation of the flowfield inside a pump is herein used as a numerical laboratory, subject to the limitations of modeling assumptions and to experimental verification. A numerical computation of the flow inside a real industrial centrifugal pump is performed that includes a very sophisticated geometry. Conversely to other computations, in this test case no simplification of the geometry was introduced. Numerical computations are obtained using spalart-Allmaras turbulence model. A detailed analysis of the turbulent flowstructure is performed for the design point and two off design conditions. Additional computations were performed in order to compare the numerical and experimental pump characteristics; these were obtained under normalized testing conditions. Further computations are presented for the pump working in reverse turbine mode (PAT). detailed analyses of the flow allow a comparison of the internal flow losses when the pump is operating in direct and reverse mode. This is also useful to help in the selection of an adequate pump geometry that can work in both modes with best efficiency.

关键词： centrifugal pump impeller turbulence modeling spalart-Allmaras PAT

Effect of La on the Corrosion Behavior and Mechanism of 3Ni Weathering steel in a simulated Marine Atmospheric Environment

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Acta Metallurgica sinica(English Letters) 2024年第2期37卷 308-324页

作者： Gang Niu Rui Yuan R.d.K.Misra Na Gong Zhi-Hui Zhang Hao-Xiu Chen Hui-Bin Wu Cheng-jia shang Xin-Ping Mao Collaborative Innovation Center of steel Technology University of Science and Technology BeijingBeijing100083China Laboratory for Excellence in Advanced steel Research Department of MetallurgicalMaterials and Biomedical EngineeringUniversity of Texas at El PasoEl PasoTX79968USA Institute of Materials Research and Engineering Agency for ScienceTechnologyand ResearchSingapore138634Singapore department of Materials science and Engineering University of TorontoTorontoONM5S 3E4Canada

The corrosion behavior and mechanism of 3Ni weathering steel in a simulated oceanic atmospheric environment are investigated in order to comprehend the impacts of La,as determined through electrochemical analysis and rust layer *** results of this study demonstrate that the addition of La enhances the corrosion resistance of 3Ni weathering steel in the marine atmospheric environment,thereby reducing the corrosion rate and improving the protection of the rust *** influence of La on corrosion resistance can be attributed to two primary ***,La functions as a grain refiner,minimizing the potential difference of the micro-regions on the substrate surface,thereby significantly reducing the corrosion of bare steel in the marine ***,La inhibits the process of Fe_(3)O_(4) oxidation back toγ-FeOOH during corrosion at the local site,thus decreasing the formation ofγ-FeOOH and enhancing the charge transfer *** research work may serve as a reference for expanding the application of rare earth elements in the field of weathering steel.

关键词： Weathering steel Rare earth Rust layer Corrosion behavior Corrosion resistance

Behavior of fluxed lime iron oxide pellets in hot metal bath during melting and refining

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International journal of Minerals,Metallurgy and Materials 2013年第4期20卷 329-337页

作者： j. Pal s. Ghorai M. C. Goswami d. Ghosh d. Bandyopadhyay s. Ghosh CsIR-National Metallurgical Laboratory department of Metallurgical and Material Engineering Jadavpur University

Lump lime as a fiux material in a basic oxygen furnace （BOF） often creates problems in operation due to its high melting point, poor dissolution property, hygroscopic nature, and fines generation tendency. To alleviate these problems, fluxed lime iron oxide pellets （FLIP） containing 30% CaO were developed in this study using waste iron oxide fines and lime. The suitable handling strengths of the pellet （crushing strength： 300 N; drop strength： 130 times） of FLIP were developed by treating with CO2 or industrial waste gas at room temperature, while no separate binders were used. When the pellet was added into hot metal bath （carbon-containing molten iron）, it was decomposed, melted, and transformed to produce low melting oxidizing slag, because it is a combination of main CaO and Fe2O3. This slag is suitable for facilitating P and C removal in refining. Furthermore, the pellet enhances waste utilization and use of CO2 in waste gas. In this article, emphasis is given on studying the behavior of these pellets in hot metal bath during melting and refining along with thermodynamics and kinetics analysis. The observed behaviors of the pellet in hot metal bath confirm that it is suitable and beneficial for use in BOF and replaces lump lime.

关键词： ore pellets lime dissolution melting refining basic oxygen converters

Vibration analysis of axisymmetric functionally graded viscothermoelastic spheres

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Acta Mechanica sinica 2014年第1期30卷 100-111页

作者： d.K.sharma j.N.sharma s.s.dhaliwal V.Walia department of Mathematics Sant Longowal Institute of Engineering and Technology department of Mathematics National Institute of Technology

The present study focuses on the analysis of free vibrations of axisymmetric functionally graded hollow spheres. The material is assumed to be graded in radial di- rection with a simple power law. Matrix Frrbenious method of extended power series is employed to derive the analytical solutions for displacement, temperature, and stresses. The dispersion relations for the existence of various types of pos- sible modes of vibrations in the considered hollow sphere are derived in a compact form. In order to explore the character- istics of vibrations, the secular equations are further solved by using fixed point iteration numerical technique with the help of MATLAB software. The numerical results have been presented graphically for polymethyl methecrylate materials in respect of natural frequencies, frequency shift, inverse quality factor, displacement, temperature change, and radial stress.

关键词： Functionally graded stresses Vibrations Fr6benius - dispersion - spherical structures

Creation and annihilation phenomena of electron and positron pairs in an oscillating field

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Chinese Physics B 2021年第7期30卷 151-156页

作者： M jiang d d su N s Lin Y j Li school of science China University of Mining and TechnologyBeijing 100083China state Key Laboratory for Geomechanics and deep Underground Engineering China University of Mining and TechnologyBeijing 100083China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

The combination of an oscillating and a static field is used to study the creation and annihilation phenomena during the pair creation *** time evolution,spatial density and momentum distribution of the created particles for a fermionic system are presented,which demonstrate that with the increasing static field intensity,the number of the created particles experiences a distinguishable decrease in every period of the oscillating field,which is caused by the annihilation phenomena between the created electrons and positrons.

关键词： pair creation computational quantum field theory strong laser field