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Successional trends and processes on a glacial foreland in Southern Iceland studied by repeated species counts

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Ecological Processes 2019年第1期8卷 138-148页

作者： taylor g.g.ausen Lawrence H.Tanner Jacobs School of Medicine and Biomedical Sciences State University of New York at BuffaloBuffaloNY 14203USA Department of Biological and Environmental Sciences Le Moyne CollegeSyracuseNY 13214USA

Introduction:Primary succession on glacial forelands is increasingly relevant as rapid glacial retreat is exposing growing land areas to plant *** investigated temporal trends,controls,and outcomes in floral succession on a subarctic glacial ***,we examined changes in community composition(mosses,low shrubs,forbs,trees,and graminoids)over long-term(decadal)and short-term(g processes responsible for the observed successional ***:The study area was the foreland of the Skaftafellsjӧkull,located in Vatnajӧkull National Park near the south coast of *** established nine transect lines at varying distances from the ice front representing surfaces of age ranging from less than one decade to over 100 *** transect consisted of five measurement stations of 1 m2 where we measured vegetative cover(VC),species richness(SR),and species density(SD)and calculated species evenness(SE).Measurements were made initially in 2007 and repeated at the same geographic coordinates in ***:VC increased with distance from the ice front from 16%to over 90%.SR and SD increased from the youngest pioneer community through a mid-successional stage corresponding to an age of over 60 but less than 100 *** VC but declining SR,SD,and SE characterized the oldest(over 100 years)bryophyte-dominated *** turnover,which involved forbs almost exclusively,increased moderately from early through midsuccessional sites and declined on older *** of the measurements made in 2014 to those made in 2007 demonstrates increased SR at mid-successional sites while SD remained relatively ***:At a small scale,colonization is controlled by local factors such as microtopography and aspect,particularly in proximity to the *** the landscape level,changes in VC and community structure are controlled by time and nutrient *** nutrient level

关键词： Primary succession glacial foreland Species richness Species density Bryophyte

Quantum Effects on Rayleigh-taylor Instability of Incompressible Plasma in a Vertical Magnetic Field

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Chinese Physics Letters 2010年第12期27卷 132-135页

作者： g. A. Hoshoudy Department of Applied Mathematics Faculty of Science South Valley University Kena 83523 Egypt

Quantum effects on Rayleigh-taylor instability of a stratified incompressible plasmas layer under the influence of vertical magnetic field are investigated. The solutions of the linearized equations of motion together with the boundary conditions lead to deriving the relation between square normalized growth rate and square normalized wave number in two algebraic equations and are numerically analyzed. In the case of the real solution of these two equations, they can be combined to generate a single equation. The results show that the presence of vertical magnetic field beside the quantum effect will bring about more stability on the growth rate of unstable configuration.

关键词： Plasma physics

Vacuum interrupter,high reliability component of distribution switches,circuit breakers and contactors

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 335-342页

作者： SLADE Paul g. MAYO Stephen SMITH R.Kirkland taylor Erik D. Eaton Electrical HorseheadsNY 14845USA

The use of vacuum interrupters(VIs)as the current interruption component for switches,circuit breakers,reclosers and contactors operating at distribution voltages has escalated since their introduction in the mid-1950’*** electrical product has developed a dominating position for switching and protecting distribution *** are even being introduced into switching products operating at transmission *** the reasons for the VI’s popularity are its compactness,its range of application,its low cost,its superb electrical and mechanical life and its ease of *** major advantage is its well-established *** this paper we show how this reliability has been achieved by design,by mechanical life testing and by electrical performance *** introduce the“sealed for life”concept for the VI’s *** discuss this in terms of what is meant by a practical leak rate for VIs with a life of over 30 *** show that a simple high voltage withstand test is an easy and effective method for monitoring the long-term vacuum *** we evaluate the need for routine inspection of this electrical product when it is used in adverse ambient environments.

关键词： Vacuum interrupter (VI) Reliability Mechanical life Electrical life

Code modernization and modularization of APEX and SWAT watershed simulation models

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International Journal of Agricultural and Biological Engineering 2015年第3期8卷 81-94页

作者： Robin A.J.taylor Jaehak Jeong Michael White Jeffrey g.Arnold Blackland Research&Extension Center Texas A&M AgriLife ResearchTempleTexas 76502USA grassland Soil&Water Research Laboratory USDA-ARS TempleTexas 76502USA

SWAT(Soil and Water Assessment Tool)and APEX(Agricultural Policy/Environmental eXtender)are respectively large and small watershed simulation models derived from EPIC(Environmental Policy Integrated Climate),a field-scale agroecology simulation *** three models are coded in Fortran and have evolved over several *** are widely used to analyze anthropogenic influences on soil and water quality and *** of the original Fortran code has been retained even though Fortran has been through several cycles of *** now provides functionality originally restricted to languages like C,designed to communicate directly with the operating system and *** can now use an object-oriented style of programming in Fortran,including inheritance,run-time polymorphism and *** order to enhance their utility in research and policy-making,the models are undergoing a major revision to use some of the new Fortran *** these new programming paradigms the developers of SWAT,APEX,and EPIC are working to make communication between the two models *** paper describes the ongoing revision of these models that will make them easier to use,maintain,modify and *** is intended that they will converge as they continue to evolution,while maintaining their distinctive features,capabilities and identities.

关键词： code modernization modularization object-oriented programming Fortran 2008 landscape-scale models APEX EPIC SWAT

Magnetospheric Boundary Layer Structure and Dynamics as Seen From Cluster and Double Star Measurements

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空间科学学报 2013年第6期33卷 577-603页

作者： Y V Bogdanova C J Owen M W Dunlop M g g T taylor A N Fazakerley Space Science and Technology Department RALChiltonDidcotOxfordshireOX11 0QXUK Mullard Space Science Laboratory University College LondonHolmbury St.MaryDorkingSurreyRH5 6NTUK Science and Robotic Exploration Directorate ESA/ESTECNoordwijkThe Netherlands

In this review,we discuss the structure and dynamics of the magnetospheric LowLatitude Boundary Layer(LLBL)based on recent results from multi-satellite missions Cluster and Double *** boundary layer,adjacent to the magnetopause on the magnetospheric side,usually consists of a mixture of plasma of magnetospheric and magnetosheath origins,and plays an important role in the transfer of mass and energy from the solar wind into the magnetosphere and subsequent magnetospheric *** southward Interplanetary Magnetic Field(IMF)conditions,this boundary layer is generally considered to be formed as a result of the reconnection process between the IMF and magnetospheric magnetic field lines at the dayside magnetopause,and the structure and plasma properties inside the LLBL can be understood in terms of the time history since the reconnection *** northward IMF conditions,the LLBL is usually thicker,and has more complex structure and *** observations confirm that the LLBL observed at the dayside can be formed by single lobe reconnection,dual lobe reconnection,or by sequential dual lobe reconnection,as well as partially by localized cross-field *** LLBL magnetic topology and plasma signatures inside the different sub-layers formed by these processes are discussed in this *** role of the Kelvin-Helmholtz instability in the formation of the LLBL at the flank magnetopause is also ***,we conclude that the LLBL observed at the flanks can be formed by the combination of processes,(dual)lobe reconnection and plasma mixing due to non-linear Kelvin-Helmholtz waves.

关键词：边界层结构磁层顶双星群集国际货币基金组织等离子体特性测量拓扑结构

Decomposing the drivers of residential space cooling energy consumption in EU-28 countries using a panel data approach

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Energy and Built Environment 2020年第4期1卷 432-442页

作者： Andreas Andreou John Barrett Peter g.taylor Paul E.Brockway Zia Wadud Sustainability Research Institute School of Earth and EnvironmentUniversity of LeedsLeedsLS29JTUK Low Carbon Energy Research group School of Chemical and Process EngineeringUniversity of LeedsLeedsLS29JTUK Spatial Modelling and Dynamics Research group Institute for Transport StudiesUniversity of LeedsLeedsLS29JTUK

While space cooling currently represents less than 1%of final energy use in the residential sector of the Euro-pean Union(EU-28),it was the fastest growing end-use during the 2000-15 period with a mean annual growth rate of 6%per ***,little is known about factors which have driven regional air-conditioning(AC)energy consumption over time,since the literature is limited to cross-sectional studies that lack differentiation between climatic and non-climatic *** projections for the EU’s electricity sector may therefore neglect the potential implications of rapidly growing AC *** develop a novel decomposition framework,which breaks down residential space cooling energy consumption in EU-28 countries into the effect of different components from 2000 to *** is extended to panel data models identifying specific drivers of space cooling’s climate-sensitive ***,we explore scenarios of residential AC energy consumption up to 2050 and evaluate their impact on summer time peak *** diffusion was found to be the key driver of space cooling energy consumption,but this effect was partly counterbalanced by efficiency *** weather influences AC equipment ownership rate in EU-28 households,personal income has a larger marginal *** baseline scenarios,AC diffusion saturates by 2050,while modestly increasing sectoral final energy ***,our range of scenario values for space cooling energy consumption in 2050 exceed the majority of those originat-ing from recently published *** a future renewables-driven electricity system,energy security risks may emerge from a scenario of fast AC up-take in new and renovated buildings,especially for colder European countries where modelled peak cooling electricity demand is shown to outgrow the projected expansion of solar *** findings have important implications for the EU’s strategy to decarbonise energy supply.

关键词： Space cooling AC diffusion Decomposition analysis Panel data model Peak demand

Prevalence and associations of non-retinopathy ocular conditions among older Australians with self-reported diabetes:The National Eye Health Survey

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International Journal of Ophthalmology(English edition) 2020年第10期13卷 1642-1651页

作者： Joshua Foreman Stuart Keel Myra B Mcguinness Jonathan g Crowston Hugh R taylor Mohamed Dirani Centre for Eye Research Australia the Royal Victorian Eye&Ear HospitalVictoria 3002MelbourneAustralia Ophthalmology Department of Surgerythe University of MelbourneVictoria 3010MelbourneAustralia Indigenous Eye Health Unit Melbourne School of Population and Global Healththe University of MelbourneVictoria 3010MelbourneAustralia Singapore Eye Research Institute Singapore National Eye Centre168751Singapore

AIM:To determine the prevalence and associations of non-retinopathy ocular conditions among older Australian adults with ***:Multistage random-cluster sampling was used to select 3098 non-indigenous Australians aged 50 y or older(46.4%male)and 1738 indigenous Australians aged 40 y or older(41.1%male)from all levels of geographic remoteness in *** underwent a standardised questionnaire to ascertain diabetes history,and a clinical examination to identify eye *** determined the prevalence of uncorrected refractive error,visually significant cataract,cataract surgery,age-related macular degeneration,glaucoma,ocular hypertension,retinal vein occlusion and epiretinal membrane among those with and without self-reported ***:Participants with self-reported diabetes had a higher prevalence of cataract surgery than those without diabetes(28.8%vs 16.9%,OR 1.78,95%CI:1.35-2.34 among non-indigenous Australians,and 11.3%vs 5.2%,OR 1.62,95%CI:1.22-2.14 among indigenous Australians).Diabetic retinopathy(DR)increased the odds of cataract surgery among self-reported diabetic indigenous and nonindigenous Australians(OR 1.89,P=0.004 and OR 2.33,Pg diabetes for≥20 y and having vision-threatening DR increased the odds of cataract surgery among indigenous Australians with diabetes(OR 3.73,P=0.001 and 7.58,Pg diabetes epidemic,interventions to reduce the impact of diabetes-related blindness should include increased cataract surgery services.

关键词： retinopathy diabetes prevalence public health national survey cataract

In situ selective laser gas nitriding for composite TiN/Ti-6Al-4V fabrication via laser powder bed fusion

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Journal of Materials Science & Technology 2020年第10期42卷 98-107页

作者： P.A.Morton H.C.taylor L.E.Murr O.g.Delgado C.A.Terrazas R.B.Wicker W.M.Keck Center for 3D Innovation The University of Texas at El PasoEl PasoTX79968USA Department of Mechanical Engineering The University of Texas at El PasoTX 79968USA Department of Metallurgical Materials and Biomedical EngineeringThe University of Texas at El PasoTX 79968USA

Laser-assisted gas nitriding of selective Ti-6Al-4V surfaces has been achieved during laser powder bed fusion fabrication by exchanging the argon build gas environment with *** variation of processing parameters allowed microdendritic Ti N surface coatings to be formed having thicknesses ranging from a few tens of microns to several hundred microns,with TiN dendrite microstructure volume fractions ranging from 0.6 to 0.75;and corresponding Vickers microindentation hardness values ranging from^7.5 gPa–9.5 *** TiN hard layers ranging from 50μm to 150μm thick were also fabricated in the laser-beam additively manufactured Ti-6Al-4V alloy producing prototype,hybrid,planar composites having alternating,ductile Ti-6Al-4V layers with a hardness of^4.5 gPa and a stiff,TiN layer with a hardness of^8.5 *** results demonstrate prospects for fabricating novel,additively manufactured components having selective,hard,wear and corrosion resistant coatings along with periodic,planar or complex metal matrix composite regimes exhibiting superior toughness and related mechanical properties.

关键词： Ti-6Al-4V TiN ceramic coatings and embedded layers Dendritic microstructures Selective laser melting Additive manufacturing Metal matrix composites Selective nitriding

Thirty-two essential questions for understanding the social-ecological system of forage fish:the case of pacific herring

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Ecosystem Health and Sustainability 2016年第4期2卷 44-55页

作者： Phillip S.Levin Tessa B.Francis Nathan g.taylor Conservation Biology Division Northwest Fisheries Science CenterNOAA Fisheries2725 Montlake Boulevard EastSeattleWashington 98112USA Puget Sound Institute University of Washington Tacoma326 East D StreetTacomaWashington 98421USA Fisheries and Oceans Canada 3190 Hammond Bay RoadNanaimoBritish Columbia V9T 1K6Canada

Forage fishes are ecologically and economically important low trophic level species,and in recent years interest in their biology and management has *** Herring are emblemat-ic of the management issues facing forage species-they are central components of the Northeast Pacific pelagic food web and support important commercial *** addition,the importance of Herring to indigenous peoples have made them cultural keystone *** employed a participatory process to promote collaborative priority-setting for this critical forage *** with managers,the fisher-ies industry,indigenous peoples,and scientists,we co-constructed a conceptual model of the Pacific Her-ring social-ecological system(SES)in the Northeast *** then identified a set of questions,that,if answered,would significantly increase our ability to sustainably manage the Herring *** objective was to generate a road map for scientists who wish to conduct useful forage fish research,for resource managers who wish to develop new research efforts that could fill critical gaps,and for public agencies and private foundations seeking to prioritize funding on forage fish issues in the *** this socio-cultural centrality comes complexity for fisheries *** participatory process highlighted the value of conceptualizing the full SES,overcame disciplinary differences in scientific approaches,research philos-ophy,and language,and charted a path forward for future research and management for forage species.

关键词： fisheries forage fish interdisciplinary science Pacific Herring Pacific Ocean social-ecological system