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Defence Technology（防务技术） 2022年第9期18卷 1563-1577页

作者： Shannon ryan Julian Berk Santu Rana Brodie McDonald Svetha Venkatesh Applied Artificial Intelligence Institute(A^(2)I^(2)) Deakin University75 Pigdons RdWaurn PondsVIC3216Australia Defence Science and Technology Group 506 Lorimer StreetFishermans BendVIC3207Australia

We present an inverse methodology for deriving viscoplasticity constitutive model parameters for use in explicit finite element simulations of dynamic processes using functional experiments, i.e., those which provide value beyond that of constitutive model development. The developed methodology utilises Bayesian optimisation to minimise the error between experimental measurements and numerical simulations performed in LS-DYNA. We demonstrate the optimisation methodology using high hardness armour steels across three types of experiments that induce a wide range of loading conditions: ballistic penetration, rod-on-anvil, and near-field blast deformation. By utilising such a broad range of conditions for the optimisation, the resulting constitutive model parameters are generalised, i.e., applicable across the range of loading conditions encompassed the by those experiments(e.g., stress states, plastic strain magnitudes, strain rates, etc.). Model constants identified using this methodology are demonstrated to provide a generalisable model with superior predictive accuracy than those derived from conventional mechanical characterisation experiments or optimised from a single experimental condition.

关键词： Constitutive modelling Finite element Bayesian optimisation Finite element model updating

Numerical Diffusion Control of a Space-Time Discontinuous Galerkin Method

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Communications in Computational Physics 2009年第2期5卷 469-483页

作者： Michel Borrel Juliette ryan ONERA BP72-29 Avenue de la Division Leclerc92322Chatillon CedexFrance

Variations on space-time Discontinuous Galerkin(STDG)discretization associated to Runge-Kutta schemes are *** new schemes while keeping the original scheme order can improve accuracy and *** analysis is made on academ... 详细信息

关键词： Gas dynamics aeroacoustics discontinuous Galerkin discretization Runge-Kutta schemes numerical diffusion control

A Multi-Flow Information Flow Tracking Approach for Proving Quantitative Hardware Security Properties

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Tsinghua Science and Technology 2021年第1期26卷 62-71页

作者： Yu Tai Wei Hu Lu Zhang Dejun Mu ryan Kastner the School of Cybersecurity Northwestern Polytechnical UniversityXi'an 710072China the School of Automation Northwestern Polytechnical UniversityXi'an 710072China the Department of Computer Science and Engineering University of CaliforniaSan DiegoCA 92093USA

Information Flow Tracking(IFT)is an established formal method for proving security properties related to confidentiality,integrity,and *** has seen promise in identifying security vulnerabilities resulting from design flaws,timing channels,and hardware Trojans for secure hardware ***,existing IFT methods tend to take a qualitative approach and only enforce binary security properties,requiring strict non-interference for the properties to hold while real systems usually allow a small amount of information flows to enable desirable ***,existing methods are inadequate for reasoning about quantitative security properties or measuring the security of a design in order to assess the severity of a security *** this work,we propose two multi-flow solutions—multiple verifications for replicating existing IFT model and multi-flow IFT *** proposed multi-flow IFT method provides more insight into simultaneous information flow behaviors and allows for proof of quantitative information flow security properties,such as diffusion,randomization,and boundaries on the amount of simultaneous information *** results show that our method can be used to prove a new type of information flow security property with verification performance benefits.

关键词： hardware security Information Flow Tracking(IFT) multi-flow IFT security property

Constraints on treeline advance in a warming climate:a test of the reproduction limitation hypothesis

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Journal of Plant Ecology 2018年第3期11卷 411-422页

作者： Dasvinder Kambo ryan K.Danby Department of Geography Queen’s University99 University AvenueKingstonOntario K7L 3N6Canada School of Environmental Studies Queen’s University99 University AvenueKingstonOntario K7L 3N6Canada

Aims Several mechanistic hypotheses have been developed to explain the existence of alpine treelines *** reproduction limita-tion hypothesis(RLH)postulates that reproductive processes such as seed production and dispersal are restricted in treeline envi-ronments,thereby limiting the establishment of new individuals in advance of extant *** its popularity,no study has tested this hypothesis in a comprehensive *** this experi-ment,we attempted to answer whether there are enough viable seeds being dispersed beyond treeline for sexually mediated tree-line advance,and what the implications of climate change might be on these *** We established 30 plots across two aspects(north ***)and three elevational habitats(forest,treeline and tundra)in a white spruce(Picea glauca)boreal forest-alpine tundra ecotone in south-west Yukon,*** each plot,tree characteristics,seed produc-tion and predispersal damage were ***,eight dispersal trays were positioned in each plot to measure seed rain,and germination trials with and without predation exclosures were constructed in a subset of plots to quantify dispersal and germina-tion *** Findings Results were highly variable both temporally and *** 2014,a mast year,69%of adult trees produced cones compared to 0.4%in the following *** density of trees in forest plots compared to treeline and tundra resulted in greater seed production at lower *** all plots,88%of seeds were damaged before dispersal or were not *** plots had significantly greater predispersal *** rain was greater in south-facing plots than north-facing *** than 2%of seeds produced on the landscape were dispersed into Tundra plots,located 50 m above *** was a net movement of seeds from the north-facing slope to the south at our study site,likely due to prevailing winds during the dispersal *** counts were more

关键词： altitudinal gradients treeline dynamics predispersal seed damage seed predation seed masts ecotones

Epidemiology of diabetic retinopathy,diabetic macular edema and related vision loss

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Eye and Vision 2015年第1期2卷 137-161页

作者： ryan Lee Tien YWong Charumathi Sabanayagam Singapore Eye Research Institute Singapore National Eye CentreSingaporeSingapore Yong Loo Lin School of Medicine National University of SingaporeSingaporeSingapore Ophthalmology and Visual Sciences Academic Clinical Program Duke-NUS Graduate Medical SchoolSingaporeSingapore

Diabetic retinopathy(DR)is a leading cause of vision-loss *** an estimated 285 million people with diabetes mellitus worldwide,approximately one third have signs of DR and of these,a further one third of DR is vision-threatening DR,including diabetic macular edema(DME).The identification of established modifiable risk factors for DR such as hyperglycemia and hypertension has provided the basis for risk factor control in preventing onset and progression of *** research investigating novel risk factors has improved our understanding of multiple biological pathways involved in the pathogenesis of DR and DME,especially those involved in inflammation and oxidative *** in DR prevalence between populations have also sparked interest in genetic studies to identify loci associated with disease *** this review,major trends in the prevalence,incidence,progression and regression of DR and DME are explored,and gaps in literature *** and novel risk factors are also extensively reviewed with a focus on landmark studies and updates from the recent literature.

关键词： Diabetic retinopathy Diabetic macular edema Epidemiology Risk factors

The Role of the p38 Pathway in Adaptive Immunity

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Cellular & Molecular Immunology 2007年第4期4卷 253-259页

作者： ryan Cook Chia-Cheng Wu Young Jun Kang Department of Immunology The Scripps Research Institute10550 North Torrey Pines RoadLa JollaCA 92037USA

Since its discovery in 1993, the mitogen-activated protein （MAP） kinase p38 has attracted much attention for its role in a wide range of cellular processes, many of which involve the immune system. Although p38 has been heavily implicated in the function of all type immune cells, research has tended focus on its role in innate immunity. In this review we attempt to highlight some of the major discoveries that have been made regarding p38＇s role in adaptive immunity, and also to discuss the possible future implications of these discoveries.

关键词： p38 MAPK adaptive immunity T cell B cell

Recent advances in multistep solution nanosynthesis of nanostructured three-dimensional complexes of semiconductive materials

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Progress in Natural Science:Materials International 2013年第1期23卷 273-285页

作者： Huajun Zhou Z.ryan Tian Department of Chemistry and Biochemistry University of ArkansasFayettevilleAR 72701USA Institute of Nanoscale Materials Sciences and Engineering University of ArkansasFayettevilleAR 72701USA

Constructing simply nanostructured zero-,one-,and two-dimensional crystallites into threedimensional multifunctional assemblies and systems at low-cost is essential and highly challenging in materials science and *** to the simply nanostructured components,a three-dimensional(3D) complex made with a precisely controlled spatial organization of all structural nanocomponents can enable us to concert functionalities from all the ***,so doing in nm-scales via a solution chemistry route may be much easier and less expensive than via other ***,we discuss herein some recent advances in multistep solution syntheses of nanostructured 3D complexes of semiconductors with a focus mainly on their synthetic strategies and detailed mechanisms.

关键词： Three dimensional Complex structures Semiconductor Multistep Solution synthesis

Alternating Direction Implicit Orthogonal Spline Collocation on Non-Rectangular Regions

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Advances in Applied Mathematics and Mechanics 2013年第4期5卷 461-476页

作者： Bernard Bialecki ryan I.Fernandes Department of Applied Mathematics and Statistics Colorado School of MinesGoldenCO 80401USA Department of Mathematics The Petroleum InstituteAbu DhabiUnited Arab Emirates

The alternating direction implicit(ADI)method is a highly efficient technique for solving multi-dimensional time dependent initial-boundary value problems on *** the ADI technique is coupled with orthogonal spline collocation(OSC)for discretization in space we not only obtain the global solution efficiently but the discretization error with respect to space variables can be of an arbitrarily high ***[2],we used a Crank Nicolson ADI OSC method for solving general nonlinear parabolic problems with Robin’s boundary conditions on rectangular polygons and demonstrated numerically the accuracy in various norms.A natural question that arises is:Does this method have an extension to non-rectangular regions?In this paper,we present a simple idea of how the ADI OSC technique can be extended to some such *** approach depends on the transfer of Dirichlet boundary conditions in the solution of a two-point boundary value problem(TPBVP).We illustrate our idea for the solution of the heat equation on the unit disc using piecewise Hermite cubics.

关键词： Alternating direction implicitmethod orthogonal spline collocation two point boundary value problem Crank Nicolson parabolic equation non-rectangular region

Re-evaluation of the function of the male specific lethal complex in Drosophila

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Journal of Genetics and Genomics 2011年第8期38卷 327-332页

作者： James Birchler Harvey Fernandez ryan Donohue Abhijit Sanyal Division of Biological Sciences 311 Tucker HallUniversity of MissouriColumbiaMO 65211USA

A set of proteins and noncoding RNAs, referred to as the male specific lethal （MSL） complex, is present on the male X chromosome in Drosophila and has been postulated to be responsible for dosage compensation of this chromosome -- the up-regulation of its expression to be equal to that of two X chromosomes in females. This hypothesis is evaluated in view of lesser known aspects of dosage compensation such as the fact that metafemales with three X chromosomes also have equal expression to normal females, which would require a down-regulation of each gene copy Moreover, when this complex is ectopically expressed in females or specifically targeted to a reporter in males, there is no increase in expression of the genes or targets with which it is associated. These observations are not consistent with the hypothesis that the MSL complex conditions dosage compensation. A synthesis is described that can account for these observations.

关键词： Dosage compensation MSL Aneuploidy Gene balance hypothesis X chromosome

High energy neutron and pion-decay gamma-ray emissions from solar flares

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Chinese Journal of Astronomy and Astrophysics 2009年第1期9卷 11-40页

作者： Edward L.Chupp James M.ryan Physics Department and Space Science Center in the Institute for the Study of Earth Oceans and Space University of New Hampshire

Solar flare gamma-ray emissions from energetic ions and electrons have been detected and measured to GeV energies since 1980. In addition, neutrons produced in solar flares with 100 MeV to GeV energies have been observed at the Earth. These emissions are produced by the highest energy ions and electrons accelerated at the Sun and they provide our only direct （albeit secondary） knowledge about the properties of the accelerator（s） acting in a solar flare. The solar flares, which have direct evidence for pion-decay gamma-rays, are unique and are the focus of this paper. We review our current knowledge of the highest energy solar emissions, and how the characteristics of the acceleration process are deduced from the observations. Results from the RHESSI, INTEGRAL and CORONAS missions will also be covered. The review will also cover the solar flare capabilities of the new mission, FERMI GAMMA RAY SPACE TELESCOPE, launched on 2008 June II. Finally, we discuss the requirements for future missions to advance this vital area of solar flare physics.

关键词： Sun -- Flares -- Particle Acceleration-Meson Production