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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

Geographical location affects size and materials used in the construction of European Pied Flycatcher(Ficedula hypoleuca) nests

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Avian Research 2019年第2期10卷 111-125页

作者： Kevin b.briggs Lucia E.biddle d.Charles deeming Joseph banks Laboratories School of Life SciencesUniversity of Lincoln

background: Nest construction is a key element of avian reproductive behaviour and the result is often a complex structure that is used for incubation of eggs, which represents an extended phenotype. It is known that nest construction is a plastic behaviour but the extent to which plasticity is observed in a single species with a wide geographical distribution is largely unknown. This study sought to better understand variation in nest size and composition across a very wide geographical area. The hypothesis suggested that location would affect size but not composition of nests of the European Pied Flycatcher (Ficedula hypoleuca). Methods: Nests and reproductive data were collected from seventeen study sites, spread over 6° of latitude and 3.3° of longitude on the island of Great britain. dimensions of nests were measured before they were deconstructed to determine the masses and types materials used in the outer nest and the cup lining. Results: Geographical variation was observed in base thickness of nests but not many other dimensions. Nests varied in composition but were mainly made of leaf, moss, bark, grass, root and fern. Moss was used more to the north and east of the study area compared with more leaf mass towards the south and west. The species of leaf and bark used in the nests varied between geographical locations. Additionally, the use of leaves or bark from a particular tree species did not reflect the incidence of the tree species in the immediate territory. Conclusions: This study showed that nest composition was affected by geographical location over a wide area. Variation between nests at each location was high and so it was concluded that differences in nest composition reflect individual selection of materials but evidence is such that it remains unclear whether this is deliberate to fulfil a specific role in the nest, or simply opportunistic with birds simply picking up materials with the appropriate characteristics as they find them outside the

关键词： breeding success Ficedula hypoleuca Latitude Longitude Nest composition Nest size Nest structure

Trajectory sampling and finite-size effects in first-principles stopping power calculations

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npj Computational Materials 2023年第1期9卷 238-246页

作者： Alina Kononov Thomas W.Hentschel Stephanie b.Hansen Andrew d.baczewski Center for Computing Research Sandia National LaboratoriesAlbuquerqueNMUSA School of Applied&Engineering Physics Cornell UniversityIthacaNYUSA Pulsed Power Sciences Center Sandia National LaboratoriesAlbuquerqueNMUSA

Real-time time-dependent density functional theory(TddFT)is presently the most accurate available method for computing electronic stopping powers from first ***,obtaining application-relevant results often involves either costly averages over multiple calculations or ad hoc selection of a representative ion *** consider a broadly applicable,quantitative metric for evaluating and optimizing trajectories in this *** methodology enables rigorous analysis of the failure modes of various common trajectory choices in crystalline *** randomly selecting trajectories is common practice in stopping power calculations in solids,we show that nearly 30%of random trajectories in an FCC aluminum crystal will not representatively sample the material over the time and length scales feasibly simulated with TddFT,and unrepresentative choices incur errors of up to 60%.We also show that finite-size effects depend on ion trajectory via“ouroboros”effects beyond the prevailing plasmon-based interpretation,and we propose a cost-reducing scheme to obtain converged results even when expensive core-electron contributions preclude large *** work helps to mitigate poorly controlled approximations in first-principles stopping power calculations,allowing 1–2 order of magnitude cost reductions for obtaining representatively averaged and converged results.

关键词： size prevailing selecting

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Acta Mechanica Sinica 2010年第4期26卷 567-572页

作者： d.J.Colquitt A.b.Movchan I.S.Jones W.daniels department of Mathematical Sciences University of Liverpool School of Engineering John Moores University Serco Assurance Walton House 404 The QuadrantBirchwood ParkRisleyWarringtonCheshireWA3 6GAUK

The paper presents a computational model for elastic waves in a structured weld adjacent to the free surface of an elastic solid. The main emphasis is on the interaction of waves with the micro-structure of the weld. Effects of localisation and channeling of waves are addressed. A model of a grain structure within the weld is also considered.

关键词： Macro-structured welds Waves in stratified media dispersion Localisation

Properties of Charmonium States in a Phenomenological Approach

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Communications in Theoretical Physics 2019年第2期71卷 192-202页

作者： Praveen P d’Souza Antony Prakash Monteiro K.b.Vijaya Kumar department of Physics St Philomena College department of Physics Mangalore University

We investigate the spectrum and decay rates of charmonium states within the framework of the non relativistic quark model by employing a Coulomb like potential from the perturbative one gluon exchange and the linear confining potential along with the potential derived from instanton vacuum to account for the hyperfine mass splitting of charmonium states in variational approach. We predict radiative E1, M1, two-photon, lepton and two-gluon decay rates of low lying charmonium states. An overall agreement is obtained with the experimental masses and decay *** have estimated the branching ratio of two gluons decaying into light hadrons.

关键词： non-relativistic quark model instantons charmonium radiative decay two gluon decay two photon decay leptonic decay branching ratio

MATHEMATICAL MOdELLING OF PHASE TRANSFORMATION FROM HOT-dEFORMEd AUSTENITE IN LOW CARbON STEELS

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Acta Metallurgica Sinica(English Letters) 2003年第3期16卷 204-210页

作者： Y.b.Xu G.d.Wang X.H.Liu State Key Laboratory of Rolling And Automation Northeastern University Shenyang 110004 ChinaState Key Laboratory of Rolling And AutomationNortheastern University Shenyang 110004 ChinaState Key Laboratory of Rolling And AutomationNortheastern University Shenyang 110004 China

On the basis of superelement model, Cahn’s transformation kinetics theory and Scheil’s additivity rule, the CCT diagrams and transformation kinetics in low carbon steel were predicted considering both undeformed and deformed conditions. The influence of deformation on phase equilibria and transformation incubation period was evaluated quantitatively. The recrystallization kinetics and the evolution of dislocation density were calculated during continuous cooling. The results show deformation considerably shortens transformation incubation period, accelerates transformation kinetics and makes CCT curve shift leftwards. The calculated CCT diagrams and the volume fraction of each phase are in good agreement with measurements.

关键词： thermodynamics transformation kinetics continuous cooling hot-deformed austenite

Ni/Al Intermetallics Plasma Transferred Arc Processing

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材料热处理学报 2004年第05B期25卷 948-951页

作者： Veronica A. b. Almeida Ana Sofia C. M. d'Oliveira Master student - PIPE Federal University of Parana Curitiba/BrazilMechanical Engineering Department Federal University of Parana Curitiba/Brazil

In-situ alloy development during surface processing allows for a limitless materials selection to protect components exposed to severe service conditions. In fact surface alloying offers the possibility to strengthen surface components with alloys that would not be possible to process otherwise. This work used Plasma transferred arc (PTA) hardfacing for surface alloying. different amounts of aluminium powder, 5-25%, were added to a Ni based superalloy, from Hastealloy C family, in the atomized form. The mixture was homogeneized in a ball mill and PTA deposited on carbon steel substrate. The influence of different processing parameters on the final surface alloy was evaluated as current intensity and depositing velocity were varied. Coatings were characterized by optical and scanning electronic microscopy, X-ray diffraction and Vickers microhardness profiles, under a 500g load. Results showed that PTA hardfacing is an adequate surface alloying. For the conditions tested increasing hardness was obtained by solid solution for the lower amounts of Al added and due to the new intermetallic phases for the richer Al mixture.

关键词： PTA合金等离子转移电弧 Ni/Al金属互化物表面处理

An Engineering Application Tool for Visual Assessment of the Equilibrium beach

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China Ocean Engineering 2007年第4期21卷 701-713页

作者： T.L.LEE d.S.JENG b.R.CHEN department of Construction Technology Leader UniversityTainan 709China division of Civil Engineering School of EngineeringPhysics and MathematicsUniversity ofDundeeDD1 4HNScotlandU.K. department of Resource and Environment Leader UniversityTainan 709China

An engineering application tool for prediction of the static equilibrium bay （ beach Mod） is established to describe two bay shape formulas by use of the programming software ＂MATLAb＂ with a graphic user interface （ GUI）. The tool is user-friendly for engineering students for the design of beach shapes. This tool was tested through application on three types of beaches in Taiwan and Australia. by implementing the concept of Headland Control, the beach Mod program allows users to draw a structure and create an ＇artificial headland. The results indicate that beach Mod can efficiently forecast beach changes as well as MEPbAY, a competing software package, while boasting a better user interface.

关键词： prediction static equilibrium bay MATLAb graphic user interface

Magnetic and Transport Properties of Mn_(0.98)Cr_(0.02)Te Epitaxial Films Grown on Al_2O_3 Substrates

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Journal of Materials Science & Technology 2014年第2期30卷 103-106页

作者： Z.H.Wang d.Y.Geng J.Li Y.b.Li Z.d.Zhang Shenyang National Laboratory for Materials Science Institute of Metal Researchand International Centre for Materials PhysicsChinese Academy of Sciences Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of Sciences

The epitaxial Mno0.98Cr0.02Te films on single crystal Al2O3 （0001） substrates were prepared by pulsed laser deposition. The X-ray diffraction and scanning electron microscopy results showed that the good continuous epitaxial film was obtained with substrate temperature of 500 ℃. When the substrate temperature reached 700 ℃, the film was island growth and the manganese oxides phase appeared. The temperature dependence of both the magnetization and electrical resistance showed a sharp rise at around 60 K due to the magnetoelastic coupling. The temperature dependence of the electrical resistance of Mno0.98Cr0.02Te provided evidence for a transition from the metallic to semiconducting state at 305 K due to the spin disorder scattering with a large contribution from the influence of magnon drag.

关键词： Magnetic properties Mno0.98Cr0.02Te films X-ray diffraction Epitaxial film