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20 个结果
  • 简介:在这研究,通过了台湾海峡的三热带气旋(TC)被分析;我们的结果与TC的紧张有关直接证明降水不是。从水预算的观点,潮湿流动集中主导、贡献为在在陆地上的海洋和几乎所有上的TC降水的70%潮湿,特别在TC发行量内。他们的空间分布也是类似的。蒸发在海洋上为降水贡献了30%潮湿,但是与时间改变了很少。潮湿流动集中能被划分成二部分:弯屈集中和潮湿移流。潮湿流动集中主要由于风集中,它在TC的西南的象限是主导的。潮湿移流位于北区域,并且当TC接近了陆地时,变得相对重要。潮湿流动集中和它的二部分在TC运动期间变化了,与乍见陆地加强和近在场的潮湿集中的收缩。三个TC盒子的垂直结构都显示潮湿集中主要在800hPa下面被限制到更低的空气,一个弱分叉区域在在550hPa附近的中间的对流层是在场的。

  • 标签: 热带气旋 降水 预算 水汽通量 水汽辐合 案例
  • 简介:Inthispaper,thenotionoftheboundedcompactapproximationproperty(BCAP)ofapair[Banachspaceanditssubspace]isusedtoprovethatifXisaclosedsubspaceofL∞withtheBCAP,thenL∞/XhastheBCAP.WealsoshowthatX*hastheλ-BCAPwithconjugateoperatorsifandonlyifthepair(X,Y)hastheλ-BCAPforeachfinitecodimensionalsubspaceY∈X.LetMbeaclosedsubspaceofXsuchthatM⊥iscomplementedinX*.IfXhasthe(bounded)approximationpropertyoforderp,thenMhasthe(bounded)approximationpropertyoforderp.

  • 标签: 闭子空间 逼近性质 紧凑型 Banach空间 运营商 共轭
  • 简介:Thispaperinvestigatestheproblemofmodelingandcontrollingpursuerconvoyinthree-dimensionalspace.Theguidancelawsappliedforconvoy,thevelocitypursuit,thedeviatedpursuitandtheproportionalnavigation,steerthepursuerusingtherateofline-of-sight(LOS)betweensuccessivepursuers.Onthebasisofthedifferentialequationsfortherange,thepitchangleofLOSandtheyawangleofLOSbetweensuccessivepursuers,theguidancelawsareproposedtoderivedecentralizedcontrolstrategyforpursuerconvoy.Theresultsconcerningthepursuerconvoyarerigorouslyproven.Simulationsareconductedtodemonstratethefeasibilityandeffectivenessoftheproposedcontrolstrategy.

  • 标签: Pursuer convoy THREE-DIMENSIONAL SPACE GUIDANCE LAWS
  • 简介:Inthispaper,twoirreversibleexothermicautocatalyticreactionswhichcarryoutincontinuousstirredtankreactor(CSTR)areconsidered.Adifferential-algebraicsystemisappliedtomodelthesechemicalreactions.Thestabilityandthedynamicbehaviorarestudiedforthedifferential-algebraicsystem.TheHopfbifurcationappearswhentheparameterexceedsacriticalvalue.Inordertoeliminatethiscomplexbehavior,thedifferential-algebraicsystemisdescribedbyasingle-inputandsingle-outputsystemwithparametervaryingwithindefiniteintervals,andthenvariablestructurecontrolwithslidingmodebasedonaspecialpowerreachinglawisdesignedtostabilizethischemicalsystem.Numericalsimulationsaregiventoillustratetheeffectivenessofthemethod.

  • 标签: Differential-algebraic systems AUTOCATALYTIC reaction HOPF BIFURCATION
  • 简介:TocomparethedevelopmentofphysicalcrustsinthreetypicalcultivatedsoilsofChina,ablacksoil(LuvicPhaeozem),aloesssoil(HaplicLuvisol),andapurplesoil(CalcaricRegosol)werepackedinsplashplateswithcoveredanduncoveredtreatments,andexposedtosimulatedrainfall.Meshescoveredabovethesurfacesofhalfofsoilsamplestosimulatetheeffectsofcropresidueoncrusting.Theresultsindicatedaprogressivebreakdownofaggregatesonthesoilsurfaceasrainfallcontinued.Thebulkdensityandshearstrengthonthesurfaceofthethreesoiltypesincreasedlogarithmicallyasrainfalldurationincreased.Duringthefirst30minofsimulatedrainfall,thepurplesoildevelopeda7-8mmthickcrustandtheloesssoildevelopeda3-4mmthickcrust.Theblacksoildevelopedadistinguishable,butstillunstable,crustafter80minofsimulatedrainfall.Soilorganicmatter(SOM)content,themeanweightdiameter(MWD)ofsoilaggregates,andsoilclaycontentwerenegativelycorrelatedwiththerateofcrustformation,whereasthepercentageofaggregatedispersion(PAD),theexchangeablesodiumpercentage(ESP),andthesiltandsandcontentswerepositivelycorrelatedwithcrusting.Mechanicalbreakdowncausedbyraindropimpactwastheprimarymechanismofcrustformationintheblacksoilwithmorestableaggregates(MWD25.0mm,PAD3.1%)andhigherSOMcontent(42.6gkg~(-1)).Slakingandmechanicaleluviationweretheprimarymechanismsofcrustformationinthepurplesoilwithlowclaycontent(103gkg~(-1)),cationexchangecapacity(CEC,228mmolkg~(-1)),ESP(0.60%),andSOM(17.2gkg~(-1)).MechanicalbreakdownandslakingwerethemostimportantintheloesssoilwithlowCEC(80.6mmolkg~(-1)),ESP(1.29%),SOM(9.82gkg~(-1)),andhighPAD(71.7%)andMWD(4.6mm).Simulatedresiduecoverreducedcrustformationinblackandloesssoils,butincreasedcrustformationinpurplesoil.

  • 标签: 中国土壤 物理 地壳形成 阳离子交换容量 模拟降雨 土壤团聚体
  • 简介:我们调查了之间的差别同温层(S类型)并且在intraseasonal时间的tropospheric(T类型)北极摆动(AO)事件可伸缩,以他们对表面空气温度的影响(坐)在北半球和与他们的空间结构联系的动态特征上。S类型AO事件证明一个平流层对流层联合了结构,当T类型事件展出了一个平流层对流层时解开的结构。在北半球上的环形的容纳的异例被发现与S类型AO事件被联系,而如此的一个环形的特征是实质地在T类型AO事件的destructed。在二种类型的对流层的不同水平结构能主要被归因于强迫的短暂旋涡反馈。至于Ttype事件的垂直地解开的结构,把他们区分开来与S类型事件的内在的动态特征在地带地限制的Rossby波浪的垂直繁殖躺着。在T类型事件,在一垂直波导存在的地方,地带地限制的Rossby波浪包能在东北亚洲上从重要高度异例发出,然后向上宣传进平流层。相反,如此的垂直繁殖不为S类型事件是明显的。在T类型事件从对流层与地带地限制的Rossby波浪的向上的注射联系的同温层的异例能进一步通过在climatological想PW和异常PW之间的干扰导致行星的波浪(PW)的异常垂直繁殖,导致最后的平流层对流层T类型事件的解开的结构。

  • 标签: 北极涛动 三维动态 ROSSBY波 垂直传播 耦合结构 类型
  • 简介:Thispaperpresentsanumericalapproachformodelingtheinteractionbetweenmultiplecracksinarectangularplateundercyclicloads.Itinvolvestheformulationoffatiguegrowthofmultiplecracktipsundermixed-modeloadingandanextensionofahybriddisplacementdiscontinuitymethod(aboundaryelementmethod)tofatiguecrackgrowthanalyses.Becauseofanintrinsicfeatureoftheboundaryelementmethod,ageneralgrowthproblemofmultiplecrackscanbesolvedinasingle-regionformulation.Inthenumericalsimulation,remeshingofexistingboundariesisnotnecessaryforeachincrementofcrackextension.Crackextensionisconvenientlymodeledbyaddingnewboundaryelementsontheincrementalcrackextensiontothepreviouscrackboundaries.Asanexample,thenumericalapproachisusedtoanalyzethefatiguegrowthofthreeparallelcracksinarectangularplate.Thenumericalresultsillustratethevalidationofthenumericalapproachandcanrevealtheefectofthegeometryofthecrackedplateonthefatiguegrowth.

  • 标签: 循环荷载作用 平行裂纹 矩形板 疲劳裂纹扩展 边界元法 数值方法
  • 简介:ThispaperanalyzesthequeuingproblemthatwasexperiencedduringtheShanghaiWorldExpoof2010.Thequeuingproblemwillbediscussedatthreelevels.Thethreelevelsincludethephysical,psychological,andsocialaspectsofthequeuingproblem.Thecollectivebehaviorofvisitorsisstudiedthroughanalyzingtheinformationfromthedifferentsources,suchas,thenetworkofelectroniceyes,theevaluationplatformbasedonmobilephonesystemandtheInternet.Ahybridinformationnetworktechnologyisimplemented.BasedontheWuli-Shili-Renli(WSR)systemmethodology,anewtheoreticalanalysisframeworkforthequeuingproblemisproposed.

  • 标签: 2010年上海世博会 排队服务系统 信息网络技术 排队问题 移动电话系统 系统方法论
  • 简介:Basedontheseismicresponsecharacteristicsofspaceframestructures,anewtypeofseismicisolationbearingdefinedasathree-dimensionalseismicisolationbearing(3DSIB)isdevelopedinthispaper.Thebearingoffersexcellentpropertiessuchasmulti-dimensionalseismicisolation,reasonablerotationcapability,goodabilitytoresistliftingload,uncoupledstiffnessinhorizontalandverticaldirections,etc.Inthe3DSIB,thehorizontaldimensionisdesignedbycombiningtheTeflonslidingdeviceandhelicalspring,whiletheverticaldimensionisdevelopedbyintroducingdiskspringsorhelicalsprings.Themathematicalmodelofthe3DSIBwasestablishedanditsperformancewiththecriticalparameterswastestedonashakingtable.Furthermore,the3DSIBwasappliedina120mspanhangarstructureandsimulatedusingSAP2000softwaretoevaluateitsperformanceinpracticalstructures.Theperformanceofthestructureswithandwithout3DSIBwascompared.Itisshownthatthehangarstructurewith3Dbearingsachievesabetterperformance.Theaxialforceandaccelerationresponseofthestructureswith3DSIBareeffectivelyreduced,whilethedisplacementresponseofthebearingiswithinthepredeterminedrange.

  • 标签: 隔震支座 三维地震 大跨度 应用 空间框架结构 SAP2000
  • 简介:Animprovedthree-dimensional(3-D)experimentalvisualizationmethodologyispresentedforevaluatingthefracturemechanismsofferriticstainlesssteelsbyin-situtensiletestingwithanenvironmentalscanningelectronmicroscope(ESEM).Thesamplesweremachinedwitharadialnotchedshapeandaslopedsurface.Bothplanarsurfacedeformationandslopingsurfacedeformation-inducedmicrovoidswereobservedduringdynamictensionexperiments,whereagreateramountofinformationcouldbeobtainedfromtheslopingsurface.Theresultsshowedthatmicrovoidsformedatthegrainboundariesofhighlyelongatedlargegrains.Themicrovoidsnucleatedintheseverelydeformedregionsgrewnearlyparalleltothetensileaxis,predominantlyalongthegrainboundaries.Themicrovoidsnucleatedattheinterfaceofparticlesandthematrixdidnotpropagateduetothehighplasticityofthematrix.Thelargemicrovoidspropagatedandshowedazigzagshapealongthegrainboundanes,seeminglyaconsequenceofthefractureoftheslipbandscausedbydislocationpile-ups.Thefinalfailuretookplaceduetothereductionoftheload-bearingarea

  • 标签: 铁素体不锈钢 拉伸变形 原位 可视化 环境扫描电子显微镜 立体
  • 简介:The‘Chuju’(楚居),oneofthebamboo-slipmanuscriptsfromtheWarringStatesPeriodkeptintheTsinghuaUniversityLibrary,providesextensiveinformationabouttheChuroyaldynasty.The‘Chuju’(楚居)acknowledgesJilian(季連),whoadoptedthesurnameofMi(羋),asthefounderoftheChustate.However,Jilianisnotincludedamongthe‘ThreeAncestorsofChu’(sanChuxian,三楚先),i.e.Laotong(老童)Zhurong(祝融),andYuxiong(鬻熊)—alsoknownasXuexiong(穴熊)—whowerejointlyinvokedandofferedsacrificesduringtheWarringStatePeriod.Thisarticleaddressthisquestionandsuggests,basedontherecordsfromthe‘Chuju’,thatJilianandYuxiongwerebrothers,andthatthedescendantsofYuxiongwerethosewhosucceededtothethroneinsteadofthoseofJilian.SincetheChuroyaldynastywasrelatedtoYuxiongandnottoJilian,Jilianwasnotincluded,becausesacrificialritesduringtheWarringStatePeriodusedtoemphasizedirectboundswiththeirancestors.

  • 标签: 季连 三楚先 世界 古典文明史
  • 简介:Asmanycountrieshaveenteredanewperiodofadjustmentanddevelopmentalcompetitioninthewakeofthefinancialcrisis,someprofoundchangesandtransformationshaveinevitablytakenplaceintheinternationalstrategicconfigurationandtheinternationalorder.AstheconnotationsandconditionsofChina’snew

  • 标签: 风险 金融危机 国际秩序 国际战略 中国
  • 简介:QTLmappingforsevenqualitytraitswasconductedbyusing254recombinantinbredlines(RIL)derivedfromajaponica-japonicaricecrossofXiushui79/CBao.Theseventraitsinvestigatedweregrainlength(GL),grainlengthtowidthratio(LWR),chalkgrainrate(CGR),chalkinessdegree(CD),gelatinizationtemperature(GT),amylosecontent(AC)andgelconsistency(GC)ofheadrice.ThreemappingmethodsemployedwerecompositeintervalmappinginQTLMapper2.0softwarebasedonmixedlinearmodel(MCIM),inclusivecompositeintervalmappinginQTLIciMapping3.0softwarebasedonstepwiseregressionlinearmodel(ICIM)andmultipleintervalmappingwithregressionforwardselectioninWindowsQTLCartographer2.5basedonmultipleregressionanalysis(MIMR).ResultsshowedthatfiveQTLswithadditiveeffect(A-QTLs)weredetectedbyallthethreemethodssimultaneously,twobytwomethodssimultaneously,and23byonlyonemethod.FiveA-QTLsweredetectedbyMCIM,ninebyICIMand28byMIMR.ThecontributionratesofsingleA-QTLrangedfrom0.89%to38.07%.AlltheQTLswithepistaticeffect(E-QTLs)detectedbyMIMRwerenotdetectedbytheothertwomethods.FourteenpairsofE-QTLsweredetectedbybothMCIMandICIM,and142pairsofE-QTLsweredetectedbyonlyonemethod.Twenty-fivepairsofE-QTLsweredetectedbyMCIM,141pairsbyICIMandfourpairsbyMIMR.ThecontributionratesofsinglepairofE-QTLwerefrom2.60%to23.78%.IntheXiu-BaoRILpopulation,epistaticeffectplayedamajorroleinthevariationofGLandCD,andadditiveeffectwasthedominantinthevariationofLWR,whilebothepistaticeffectandadditiveeffecthadequalimportanceinthevariationofCGR,AC,GTandGC.QTLsdetectedbytwoormoremethodssimultaneouslywerehighlyreliable,andcouldbeappliedtoimprovethequalitytraitsinjaponicahybridrice.

  • 标签: QTL定位 RIL群体 品质性状 杂交粳稻 统计模型 分析基
  • 简介:在这研究,与起始的不安(CNOP-I)有关的有条件的非线性的最佳的不安的途径被采用为三主要木质的植物在植物数量调查最大的变化(适度的broadleaved常绿树,适度的broadleavedsummergreen,和北方的needleleaved常绿树)在中国。调查用一个最先进的Lund-Potsdam-Jena动态全球植被模型(LPJDGVM)在陆地使用紧张的某个范围以内被进行。CNOP-I表示采伐森林和罐头的一个班关于起始的不安被认为陆地使用的一种类型。当CNOP-I表示的采伐森林为所有三植物有一样的紧张时,在在北中国常绿树的北方的needleleaved的植物数量的变化在南部的中国比在常绿树的适度的broadleaved和适度的broadleavedsummergreen的植物数量的变化大。作为采伐森林紧张增加,在功能的类型碳改变的三木质的植物的植物数量变化,以一种非线性的方式。陆地使用在上的影响种功能的类型因为在气候状况和陆地使用之间的相互作用没在LPJ模型被考虑,是次要的。最后,网上的采伐森林的不同影响三植物的主要生产功能的类型被为粗野主要生产和自造营养物质的呼吸建模分析。我们的结果建议CNOP-I途径是为探索陆上的生态系统的非线性、不同的回答打使用的一个有用工具。

  • 标签: 土地利用类型 中国北方 木本植物 植被模型 波茨坦 反应
  • 简介:Controlofthespatiotemporalpatternsnearthecodimension-threeTuring–Hopf–Wavebifurcationsisstudiedbyusingtime-delayedfeedbackinathree-variableBrusselatormodel.LinearstabilityanalysisofthesystemshowsthatthecompetitionamongtheTuring-,Hopf-andWave-modes,thewavenumber,andtheoscillationfrequencyofpatternscanbecontrolledbychangingthefeedbackparameters.TheroleofthefeedbackintensityPuplayedoncontrollingthepatterncompetitionisequivalenttothatofPw,butoppositetothatofPv.TheroleofthefeedbackintensityPuplayedoncontrollingthewavenumberandoscillationfrequencyofpatternsisequivalenttothatofPv,butoppositetothatofPw.Whentheintensitiesoffeedbackareappliedequally,changingthedelayedtimecouldnotalterthecompetitionamongthesemodes,however,itcancontroltheoscillationfrequencyofpatterns.Theanalyticalresultsareverifiedbytwo-dimensional(2D)numericalsimulations.

  • 标签: 延迟反馈控制 CWA BRUSSELATOR模型 图灵 余维 ve
  • 简介:Asemi-implicit3-Dnumericalformulationforsolvingnon-hydrostaticpressurefree-surfaceflowsonanunstructured,sigmagridisproposed.Pressure-splittingand9semi-implicitmethodsareinheritedandreformedfromCasulli'sz-coordinateformulation.Thenon-orthogonalsigma-coordinatetransformationleadstoadditionalterms.Theresultinglinearsystemforthenon-hydrostaticcorrectionisdiagonallydominantbutunsymmetric,anditissolvedbytheBiCGstabmethod.Incontrastwithz-coordinatenon-hydrostaticmodels,thenewmodelfitsverticalboundariesmuchbetter,whichisimportantforthelong-timesimulationofsedimenttransportandriverbeddeformation.Alock-exchangedensityflowiscomputedtodeterminewhetherthenewschemeisabletosimulatenon-hydrostaticfree-surfaceflows.ThenewmodelisfurtherverifiedusingthefielddataofanaturalriverbendofthelowerYangtzeRiver.Goodagreementbetweensimulationsandearlierresearchresults,fielddataisobtained,indicatingthatthenewmodelisapplicabletohydraulicprojectsinrealrivers.

  • 标签: 三维数值模型 自由表面流动 静水压力 非结构化 半隐式 电网