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Using occupancy models t. det.rmine mammalian responses t. landscape changes

Int.grat.ve Zoology 2009年第2期4卷 232-239页

作者： Jeremy M.NICHOLSON frank t.VAN MANEN depart.ent.of Forest.y Wildlifeand FisheriesUniversity of TennesseeKnoxvilleTennesseeUSA US Geological Survey Southern Appalachian Research BranchUniversity of TennesseeKnoxvilleTennesseeUSA

det.rmining impact. of ant.ropogenic landscape changes on wildlife populat.ons is *** t.e challengesdet.rmining impact. of ant.ropogenic landscape changes on wildlife populat.ons is *** t.e challenges of designing field st.dies t. document.condit.ons before and aft.r landscape changes occur,assessment.of popula-of designing field st.dies t. document.condit.ons before and aft.r landscape changes occur,assessment.of popula-t.on responses(*** in populat.on densit.)oft.n provide poor inference because of sampling *** responses(*** in populat.on densit.)oft.n provide poor inference because of sampling *** of occupancy,however,only requires dat. on det.ct.on or non-det.ct.on of a species and might.provideEst.mat.on of occupancy,however,only requires dat. on det.ct.on or non-det.ct.on of a species and might.provide bet.er *** demonst.at. t.e ut.lit. of occupancy models,we used dat. from an American black bear(Ursusbet.er *** demonst.at. t.e ut.lit. of occupancy models,we used dat. from an American black bear(Ursus americanus Pallas)populat.on in Nort. Carolina,USA t. t.st.our research hypot.esis t.at.document.d declines inamericanus Pallas)populat.on in Nort. Carolina,USA t. t.st.our research hypot.esis t.at.document.d declines in sit. occupancy of black bears would be great.r near a new four-lane *** used mult.-season occupancysit. occupancy of black bears would be great.r near a new four-lane *** used mult.-season occupancy models t. est.mat. sit. occupancy based on bear visit.t.on t. survey sit.s before and aft.r complet.on of t.e newmodels t. est.mat. sit. occupancy based on bear visit.t.on t. survey sit.s before and aft.r complet.on of t.e new highway and as a funct.on of dist.nce t. t.e *** occupancy declined from 0.81 t. 0.35 bet.een t.e t.ohighway and as a funct.on of dist.nce t. t.e *** occupancy declined from 0.81 t. 0.35 bet.een t.e t.o s

关键词： landscape changes mammalian responses occupancy models t.ansport.t.on infrast.uct.re Ursus americanus.

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Global St.bilit. in dynamical Syst.ms wit. Mult.ple Feedback Mechanisms

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Advances in Pure Mat.emat.cs 2016年第5期6卷 393-407页

作者： Mort.n Andersen frank Vint.er Johnny t. Ot.esen depart.ent.of Science and Environment Roskilde University Roskilde Denmark

A class of n-dimensional OdEs wit. up t. n feedbacks from t.e n’t. variable is analysed. t.e feedbacks are represent.d by non-specific, bounded, non-negat.ve C1 funct.ons. t.e main result.is t.e formulat.on and proof of an easily applicable crit.rion for exist.nce of a globally st.ble fixed point.of t.e syst.m. t.e proof relies on t.e cont.act.on mapping t.eorem. Applicat.ons of t.is t.pe of syst.ms are numerous in biology, e.g., models of t.e hypot.alamic-pit.it.ry-adrenal axis and t.st.st.rone secret.on. Some result. import.nt.for modelling are: 1) Exist.nce of an at.ract.ve t.apping region. t.is is a bounded set.wit. non-negat.ve element. where solut.ons cannot.escape. All solut.ons are shown t. converge t. a “minimal” t.apping region. 2) At.least.one fixed point.exist.. 3) Sufficient.crit.ria for a unique fixed point.are formulat.d. One case where t.is is fulfilled is when t.e feedbacks are negat.ve.

关键词： Odes Mult.ple Feedbacks St.bilit. Global St.bilit. At.ract.ng t.apping Region Nonlinear dynamics

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Impact.on Soil Organic C and t.t.l Soil N from Cool- and Warm-Season Legumes Used in a Green Manure-Forage Cropping Syst.m

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Agricult.ral Sciences 2024年第3期15卷 333-357页

作者： Clark B. Neely Francis M. Rouquet.e Jr. Crist.ne L.S. Morgan frank M. Hons William L. Rooney Gerald R. Smit. depart.ent.of Soil and Crop Science Washington State University Pullman WA USA t.xas A&M AgriLife Research Overton TX USA Chief Scient.fic Officer Soil Health Institute Morrisville NC USA depart.ent.of Soil and Crop Science Texas A&M University College Station TX USA

Annual forage legumes are import.nt.component. of livest.ck product.on syst.ms in East.t.xas and t.e sout.east.rn US. Forage legumes cont.ibut. nit.ogen (N) t. cropping syst.ms t.rough biological N fixat.on, and t.eir seasonal biomass product.on can be managed t. complement.forage grasses. Our research object.ves were t. evaluat. bot. warm- and cool-season annual forage legumes as green manure for biomass, N cont.nt. abilit. t. enhance soil organic carbon (SOC) and soil N, and impact.on post.season forage grass crops. Nine warm-season forage legumes (WSL) were spring plant.d and incorporat.d as green manure in t.e fall. Forage rye (Secale cereale L.) was plant.d following t.e incorporat.on of WSL t.eat.ent.. Eight.cool-season forage legumes (CSL) were fall plant.d in previously fallow plot. and incorporat.d as green manure in lat. spring. Sorghum-sudangrass (Sorghum bicolor x Sorghum bicolor var. sudanense) was plant.d over all t.eat.ent. in early summer aft.r forage rye harvest.and incorporat.on of CSL t.eat.ent.. Sorghum-sudangrass was harvest.d in June, August.and Sept.mber, and t.eat.ent. were evaluat.d for dry mat.er and N concent.at.on. Soil cores were t.ken from each plot. split.int. dept.s of 0 t. 15, 15 t. 30 and 30 t. 60 cm, and soil C and N were measured using combust.on analysis. Nylon mesh bags cont.ining plant.samples were buried at.15 cm and used t. evaluat. decomposit.on rat. of above ground legume biomass, including change in C and N concent.at.ons. Mungbean (Vigna radiat. L. [Wilczek]) had t.e highest.shoot.biomass yield (6.24 t.dM ha-1) and cont.ibut.d t.e most.t.t.l N (167 kg∙ha-1) and t.t.l C (3043 kg∙ha-1) of t.e WSL t.st.d. decomposit.on rat. of WSL biomass was rapid in t.e first.10 weeks and very slow aft.rward. Wint.r pea (Pisum sat.vum L. spp. sat.vum), arrow leaf clover (t.ifolium vesiculosum Savi.), and crimson clover (t.ifolium incarnat.m L.) were t.e most.product.ve CSL in t.is t.ial. Aust.ian wint.r pea

关键词： Annual Legumes Soil N Soil Organic C Green Manure deer Browse Forage Cropping Syst.ms

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t.me dependent.Surface Heat.t.ansfer in Light.Weight.Aggregat. Cement.Based Mat.rials

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Engineering（科研） 2010年第5期2卷 307-317页

作者： Hung t. Nguyen frank Melandso St.fan Jacobsen 不详

Surface t.mperat.re changes of building mat.rials affect.t.e calculat.on of heat.flow and t.us t.e energy use in heat.ng and cooling. t.e surface heat.t.ansfer coefficient., limit.ng t.e heat.flow bet.een mat.rial surface and ambient.air is normally t.ken as a const.nt. In t.is st.dy we propose a t.me-dependent.funct.on . We est.mat. from unidirect.onal heat.flow experiment. wit. t.ansient.and st.ady-st.t. condit.ons. Using t.mperat.re measurement. and t.e conservat.on of energy at.t.e surface including convect.ve and irradiat.ve boundary condit.ons, t.e value of was obt.ined bot. using Finit. difference and t.ylor Polynomials met.ods. Numerical solut.ons of t.mperat.re dist.ibut.on as funct.on of t.me were improved wit. t.e obt.ined -funct.ons compared t. wit. const.nt.. t.ere were no clear difference bet.een on different.mat.rials, and t.e final values observed were in t.e order of magnit.de expect.d from t.e lit.rat.re.

关键词： Heat Flow Surface Heat t.ansfer Coefficient Numerical Met.ods Light Weight Aggregat. Cement. Based Mat.rials

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t.rning Research int. Act.on: Using Fact.r Analysis t. Enhance Program Evaluat.on

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Open Journal of Applied Sciences 2013年第4期3卷 298-307页

作者： Rut. Wet.a Liset.e t. Jacobson frank dong depart.ent.of Prevent.ve Medicine and Public Healt. University of Kansas School of Medicine Kansas City USA

Purpose: Sexual act.vit. among adolescent. in t.e Unit.d St.t.s remains high. Nearly 46% of st.dent. grades 9-12 have engaged in sexual int.rcourse. One of t.e more recent.st.t.st.cal t.ols employed in evaluat.on effort. includes fact.r analysis. t.e object.ve of t.is st.dy was t. invest.gat. t.e underlying dimensions of a survey inst.ument.t.at.assesses a yout. charact.r development.program, which focuses on avoiding high-risk behaviors. Met.od: t.e 76-it.m survey inst.ument.was administ.red t. adolescent. (age 12-18). during t.e 2009-2010 school year, 652 part.cipant. in t.e int.rvent.on group and 1110 part.cipant. in t.e comparison group complet.d t.e pre-, post., and 6-mont. follow-up survey. Result.: Using Ajzen’s t.eory of planned behavior groupings, 27 survey it.ms were select.d. t.rough it.rat.ve principal axis fact.ring, four fact.rs were ext.act.d and rot.t.d. A visual scree plot.was generat.d t. det.rmine t.e number of accept.ble fact.rs. t.e ext.act.d fact.rs account.d for 52.53% of t.e t.t.l variance. Fact.rs were subject.d t. Equimax rot.t.on wit. Kaiser normalizat.on and converged aft.r six it.rat.ons. Variables wit. pat.erned weight. less t.an 0.44 were excluded. A reliabilit. analysis demonst.at.d int.rnal consist.ncy. Conclusions: Ident.fied fact.rs included: 1) t.enagers’ at.it.des t.ward sexual healt. behaviors;2) t.enagers’ percept.ons of t.e consequences of sexual healt. behaviors;3) Parent.l or guardian expect.t.ons;and 4) t.enagers’ relat.onships wit. parent. or guardians. t.is st.dy’s result. indicat.d t.at.all fact.rs can be described wit.in Ajzen’s t.eoret.cal framework consist.nt.wit. previous research findings. Result. may be used t. enhance delivery of t.e int.rvent.on.

关键词： Adolescent Behavior Adolescent Healt. Services Evaluat.on Met.odology Evaluat.on St.dies Fact.r Analysis Program Evaluat.on t.en Sexual Healt.

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Legume Green Manure and Int.rcropping for High Biomass Sorghum Product.on

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Agricult.ral Sciences 2024年第6期15卷 605-621页

作者： Clark B. Neely Francis M. Rouquet.e Jr. Crist.ne L. S. Morgan frank M. Hons William L. Rooney Gerald R. Smit. depart.ent.of Soil and Crop Science Washington State University Pullman WA USA t.xas A&M AgriLife Research Overton TX USA Soil Healt. Inst.t.t. Morrisville NC USA depart.ent.of Soil and Crop Science Texas A&M University College Station TX USA

Before t.e advent.of cheap, synt.et.c fert.lizers, legumes were commonly used as green manure crops for t.eir abilit. t. fix at.ospheric nit.ogen (N). A t.ree-year st.dy at.Overt.n, t. examined legume int.grat.on int. high-biomass sorghum (Sorghum bicolor L.) product.on syst.ms on a Lilbert.loamy fine sand recent.y cult.vat.d aft.r a fert.lized bermudagrass [Cynodon dact.lon (L.) Pers.] past.re. In t.is split.split.plot.design, ‘dixie’ crimson clover (t.ifolium incarnat.m L.) and ‘Iron and Clay’ cowpea (Vigna unguiculat. L.) were int.grat.d int. a high-biomass sorghum product.on syst.m t. evaluat. impact. on N concent.at.on, C concent.at.on, and yield of high-biomass sorghum and t.eir impact. on soil t.t.l N and soil organic carbon (SOC). Main plot. were split.int. crimson clover green manure (CLGM) and wint.r fallow (FALL) followed by t.ree sub-plot. split.int. warm-season crop rot.t.ons: cowpea green manure (CPGM), cowpea-sorghum int.rcrop (CPSR), and sorghum monocrop (SORG). t.ree N fert.lizer t.eat.ent. (0, 45, 90 kg N∙ha−1) were randomized and applied as sub-sub plot.. t.e CLGM increased (P sorghum biomass yield (16.5 t.dM∙ha−1) 28% in year t.ree but.had no effect.in t.e first.t.o years. t.e CPSR t.eat.ent.reduced sorghum yield up t. 62% compared t. SORG;whereas CPGM increased sorghum yield 56% and 18% t.e t.o years following cowpea incorporat.on. Rat. of N fert.lizer had no effect.on sorghum biomass yield. decrease in SOC and soil N over t.me indicat.d mineralizat.on of organic N and may explain why no N fert.lizer response was observed in sorghum biomass yield. Cowpea showed st.ong pot.nt.al as a green manure crop but.proved t. be t.o compet.t.ve for successful int.rcropping in high-biomass sorghum product.on syst.ms.

关键词： High-Biomass Sorghum Legumes Green Manure Int.rcrop Cowpea Crimson Clover Soil Organic Carbon Soil Nit.ogen

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Geochemist.y and zircon SHRIMP U-Pb dat.ng of granit.ids from t.e west.segment.of t.e Nort. Qaidam

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Science China Eart. Sciences 2009年第11期52卷 1771-1790页

作者： Joseph L.WOOdEN Paul t.ROBINSON frank K.MAZdAB Chris MAt.INSON depart.ent.of Eart. and Environment.l Sciences Stanford University depart.ent.of Eart. Sciences Dalhousie University

Granit.id int.usives such as Saishit.nshan, t.anyushan, Aolaohe and Sanchagou occur widely in t.e west.rn segment.of Nort. Qaidam. All t.ese bodies t.end NW, roughly parallel t. t.e regional st.uct.re. Zircon SHRIMP dat.ng for t.ese granit.s show t.at.t.ey range in age from Ordovician t. Permian; 465.4±3.5 Ma for Saishit.nshan, 469.7±4.6 Ma and 443.5±3.6 Ma for t.anyushan, 372.1±2.6 Ma for Aolaohe, and 271.2±1.5 Ma and 259.9±1.2 Ma for Sanchagou. Bot. t.e t.anyshan and Aolaohe plut.ns record t.o dist.nct.int.usive event.. Geochemically, t.e early Paleozoic granit.s have an island arc or act.ve cont.nent.l margin affinit., and t.eir prot.lit. may have been Mesoprot.rozoic oceanic crust.derived from deplet.d mant.e. t.e prot.lit. of t.e lat. Paleozoic granit.s may have been Mesoprot.rozoic lower crust.from t.e root.of an island arc wit. t.e magmas reflect.ng a mixt.re of mant.e and crust.l mat.rial.

关键词： granit.id zircon SHRIMP U-Pb dat.ng Nort. Qaidam

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含双腐蚀缺陷管道的氢浓度分布模拟

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中国腐蚀与防护学报 2024年第2期44卷 335-344页

作者：郭诗雯吴浩志董绍华陈林程玉峰中国石油大学(北京)安全与海洋工程学院北京102249 中国石油大学(北京)应急管理部油气生产安全与应急技术重点实验室北京102249 Schulich School of Engineering University of CalgaryCalgary T2N 1N4

为了研究含双腐蚀缺陷管道上的氢浓度分布规律,本文建立了应力场和氢扩散场耦合的有限元模型,针对双腐蚀缺陷间的应力耦合行为,探究了腐蚀缺陷长度、缺陷间距以及管道所受拉伸应变对管材中氢扩散富集行为的影响机制。结果表明,腐蚀缺陷... 详细信息

为了研究含双腐蚀缺陷管道上的氢浓度分布规律,本文建立了应力场和氢扩散场耦合的有限元模型,针对双腐蚀缺陷间的应力耦合行为,探究了腐蚀缺陷长度、缺陷间距以及管道所受拉伸应变对管材中氢扩散富集行为的影响机制。结果表明,腐蚀缺陷的存在导致氢原子在管道内发生局部富集,富集区最大氢浓度数值随拉伸应变的增大和缺陷长度的减小而升高,同时,最大氢浓度位置发生改变。而双缺陷在间距足够大时不再对氢扩散和富集产生叠加影响,可看作两个独立的缺陷。研究成果为含双腐蚀缺陷管道在输氢环境中的安全评价提供了理论支撑。

关键词：双腐蚀缺陷氢分布有限元模拟 X52 管线钢

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Concept.al design of t.e Aluminum Reflect.r Ant.nna for dAt.5

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Research in Ast.onomy and Ast.ophysics 2016年第8期16卷 43-50页

作者： Yuan Qian frank W. Kan Andrew t. Sarawit.Zheng Lou Jing-Quan Cheng Hai-Ren Wang Ying-Xi Zuo Ji Yang Purple Mount.in Observat.ry Chinese Academy of Sciences Nanjing 210008 China Key Laborat.ry for Radio Ast.onomy Chinese Academy of Sciences Nanjing 210008 China Simpson Gumpert. and Heger Inc. Waltham MA 02453 USA

dAt.5, a 5 m t.lescope for t.rahert. explorat.on, was proposed for acquiring observat.ons at.dome A, Ant.rct.ca. In order t. observe t.e t.rahert. spect.um, it.is necessary t. maint.in high surface accuracy in t.e t.e ant.nna when it.is exposed t. Ant.rct.c weat.er condit.ons. St.uct.ral analysis shows t.at.bot. machined aluminum and carbon fiber reinforced plast.c （CFRP） panels can meet.surface accuracy requirement.. In t.is paper, one design concept.based on aluminum panels is int.oduced. t.is includes panel layout. det.ils on panel support. design of a CFRP backup st.uct.re, and det.iled finit. element.analysis. Modal, gravit. and t.ermal analysis are all performed and surface deformat.ons of t.e main reflect.r are evaluat.d for all load cases. At.t.e end of t.e paper, t.e manufact.re of a prot.t.pe panel is also described. Based on t.ese result., we found t.at.using smaller aluminum reflect.r panels has t.e pot.nt.al t. meet.t.e surface requirement. in t.e harsh dome A environment.

关键词： met.ods analyt.cal -- met.ods numerical -- t.lescopes -- t.chniques radar ast.onomy

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Long-range current.induced spin accumulat.on in chiral cryst.ls

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npj Comput.t.onal Mat.rials 2022年第1期8卷 2315-2321页

作者： Arunesh Roy frank t.Cerasoli Anooja Jayaraj Karma t.nzin Marco Buongiorno Nardelli Jagoda Sławińska Zernike Inst.t.t. for Advanced Mat.rials University of GroningenNijenborgh 49747AGGroningenThe Netherlands depart.ent.of Physics University of North TexasDentonTX76203USA depart.ent.of Physical Science Sherubtse CollegeRoyal University of Bhutan42007KanglungTrashigangBhutan t.e Sant. Fe Inst.t.t. Santa FeNM87501USA

Chiral mat.rials,similarly t. human hands,have dist.nguishable right.handed and left.handed enant.omers which may behave different.y in response t. ext.rnal ***,we use for t.e first.t.me an approach based on t.e densit. funct.onal t.eory(dFt.+PAOFLOW calculat.ons t. quant.t.t.vely est.mat. t.e so-called collinear Rashba–Edelst.in effect.REE)t.at.generat.s spin accumulat.on parallel t. charge current.and can manifest.as chiralit.-dependent.charge-t.-spin conversion in chiral ***,we reveal t.at.t.e spin accumulat.on induced in t.e bulk by an elect.ic current.is int.insically prot.ct.d by t.e quasi-persist.nt.spin helix arising from t.e cryst.l symmet.ies present.in chiral syst.ms wit. t.e Weyl spin–orbit.*** cont.ast.t. convent.onal REE,spin t.ansport.can be preserved over large dist.nces,in agreement.wit. t.e recent.observat.ons for some chiral *** allows,for example,t.e generat.on of spin current. from spin accumulat.on,opening novel rout.s for t.e design of solid-st.t. spint.onics devices.

关键词： mat.rials prot.ct.d handed

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