简介：Inphasefieldfracturemodelsthevalueoftheorderparameterdistinguishesbetweenbrokenandundamagedmaterial.Atcrackfacestheorderparameterinterpolatessmoothlybetweenthesetwostatesofthematerial,whichcanberegardedasphases.Thecrackevolutionfollowsimplicitlyfromthetimeintegrationofanevolutionequationoftheorderparameter,whichiscoupledtothemechanicalfieldequations.Amongotherphenomenaphasefieldfracturemodelsareabletoreproducecracknucleationininitiallysoundmaterials.Fora1Dsettingithasbeenshownthatcracknucleationistriggeredbythelossofstabilityoftheunfractured,spatiallyhomogeneoussolution,andthatthestabilitypointdependsonthesizeoftheconsideredstructure.Thisworknumericallyinvestigatestowhichextendsizeeffectsarereproducedbythe2Dphasefieldmodel.Exemplarily,afiniteelementstudyoftheholesizeeffectisperformedandthesimulationresultsarecomparedtoexperimentaldata.

简介：数字建模具有在理解地区性的地下水系统的行为的关键重要性。然而，当在长时间跨度上执行高分辨率的模拟时，为能力建模上的需求是集中的。这份报纸论述一个平行程序的应用程序加快在诺思中国平原地下水流动系统当模特儿详细说明。平行程序被在我们的并行计算的框架上重建著名MODFLOW程序实现，它被设计基于补丁的平行数据结构和算法，但是维持compute流动和MODFLOW的功能完成。有超过100万个格子和时间的一十年的详细模型被解决了。平行模拟结果对观察数据和这二个数据通常在好同意的地被检验。为在答案时间的比较，在32个核心上跑的平行程序比最快的基于MICCG的MODFLOW程序快6倍、比基于GMG的MODFLOW程序快11倍。因此，当使用平行程序时，显著计算时间能被节省，它便于在北方中国平原的快速的建模和地下水流动系统的预言。

简介：Thesimulationofthewholeship-bridgecollisionprocesscanbeeffectivelycarriedoutbynonlineardynamicfiniteelementmethod.Basedonthesimpledescriptionofthetheory,ascenarioofa40000DWToiltankercollidingwithabridgeacrosstheYangtzeRiverisdesignedforsimulation.Thetechnologyofstructuremodelingandthedeterminationofrelatedparametersareintroduced.Thedeformationofthebulbbow,thehistoryofcollisionforcechange,theexchangeofcollisionenergyandthestressdistributionofthebridgepieraredescribedindetail,whichareofgreatvaluetobridgede-signandbridgepierdamageestimation,Somemechanicalcharactersintheprocessofship-bridgecollisionaredescribed.Moreaccurateresultscanbeproducedbyfiniteelementmethodthanthatbyempiricalformulasandsimplifiedanalyticalmethods.

简介：AbackflowmodelofPSSprocessdescribingthecontinuouscounter-currentionexchangecolumnisproposedinthispaper.Theresultsofsimulationareinagreementwithexperimentaldataconsiderably.

简介：Theelectric-staticbodyforcemodelisobtainedbysolvingMaxwell’selectromagneticequations.Basedontheelectro-staticmodel,numericalmodelingofflowaroundacylinderwithadielectricbarrierdischarge(DBD)plasmaeffectisalsopresented.Theflowstreamlinesbetweenthenumericalsimulationandtheparticleimagevelocimetry(PIV)experimentareconsistent.Accordingtothenumericalsimulation,DBDplasmacanreducethedragcoefficientandchangethevortexsheddingfrequenciesofflowaroundthecylinder.

简介：Inordertobetterassesstheperformanceofwirelesscommunicationsystems,itisdesirabletoproducemultipleRayleighfadingenvelopeswithspecifiedcorrelations.Inthispaper,weanalyzetheoreticallyaprocedurewhichgeneratescorrelatedGaussianrandomvariablesfromindependentGaussianrandomvariablesandgiveaphysicalexplanationforthelimitationofthisprocedure.Then,basedonsomeuncorrelatedRayleighfadingenvelopes,asimplebutefficientprocedureforgeneratinganarbitrarynumberofcross-correlatedRayleighfadingenvelopesisproposed.Simulationresultsandcomputationalcomplexityanalysisarepresented,whichshowthattheproposedmethodhassomeadvantages,suchashighaccuracy,lowcomputationalcomplexityandeasyimplementation,overtheconventionalsimulationmethod.

简介：

简介：Elbowdraft-tubesarewidelyusedinlargeandmedium-sizedhydropowerstationsinmanycountries.Duringtheapplication,handlingthesomatotypeofelbowtubeshasbeenfoundchallenging:inordertomaintainthedesignedshapeofdrafttubeandtomeettherequirementofconstructionlofting,theconfigurationofreinforcingbarsandthefabricationoftemplates,thegeometryofelbowtubeshastobeaccuratelycalculatedtodrawengineeringgraphics.Basedonthederivedequationsinthispaper,themotionofelbowtubecurveenvelopeissimulatedbyusingcomputers,whichshowsdirectlythesmoothnessofthecurveandprovidesdynamicsimulationforthestudyandoptimizationofthedesignandconstructionofelbowdrafttubes,alongwiththefrontviewandbottomview.

简介：一个二维的数字模型被建议在江苏省从一个发电厂模仿热分泌物。在模型的方程在于oftwo维的非稳定的浅水区方程和热废物搬运方程。Finitevolume方法(FVM)习惯于discretize切开的浅水区方程，和流动差别(FDS)计划被使用。有一样的温度增长的计算区域在海水上显示出热分泌物的效果。在模仿的结果和试验性的数据hows之间的比较好同意。它显示这个方法能在沿海的区域在热传递模拟给高精确。

简介：

简介：

简介：

简介：一个新估计方法被建议，它利用unscentedtransform方法，因此，真平均数和协变性更精确地被接近。没有为EKF必要的linearization进程，新方法能被用于非线性的系统，并且它不要求噪音的Gaussian分布并且什么“s更多的，它实现和更精确的评价特征的容易使它能在卫星轨道模拟的实验表明它的好性能。数字实验证明unscentedKalman过滤器的申请比EKF更有效。

简介：在这研究，一个新数学模型被开发二部分创作了，包括为模仿近的差错地面运动的主导的速度脉搏的泛音和多项式表情。基于建议速度功能，为扎根的加速的相应表情和排水量时间历史也被导出。建议模型然后在下一代变细(NGA)工程图书馆用在差错地面运动附近像脉搏的选择的一些被适合。新模型简单处于良好的竟技状态而且与精确的高水平在差错记录附近模仿实际速度的长时期的部分不仅。建议基于模型的有弹性的反应系列与在脉搏的占优势的频率的邻居的近的差错记录兼容，这被显示出。结果显示建议模型足够地模仿时间历史的部件。最后，建议脉搏的精力与实际记录的精力相比证实相容性。

简介：ThetransientresponsetolongitudinalimpactofflexiblerodswithHertzcontactiscloselyrelatedtotheextentofdeformationswithdifferentimpactparameters.BymeansofLS-DYNA,fordifferentradiusanddifferentspeeds,thelongitudinalimpactofahammerwitharoundedendonadrillrodisnumericallysimulatedinthisarticle.Simulationsdemonstratethatthereisanobviousdif-ferencebetweenanalyticalsolutionandnumericalsolutiononconditionofshortcurvatureradius.Inthecircumstancecontactpressureincreases,theboundaryoftheyieldzoneexceedsthatofthecontactzone,andthesignificantplasticdeformationreducestheintensityofcontactpressurepulse.Contactforce-timecurvesinloadingandunloadingphasesshiftdown.Thenumericalsolutionisingoodagree-mentwithanalyticalsolutiononconditionoflargecurvatureradiusandimpactspeeds.Thedeforma-tionofyieldregionisconstrainedbythesurroundingelasticregionandnosignificantplasticdeforma-tionappears.

简介：受到动人的负担的一座带子浮桥桥的一个数学模型用简单地支持的横梁的理论被提出。动人的负担模型的二种类型被使用，第一个一moving-constant-force模型和第二个一动人团的模型。用负担的两种类型，当使遭到了到单个移动负担然后多重移动负担时，一座带子浮桥桥的动态行为被模仿。当模特儿在MATLAB软件用完了Simulink包裹。结果显示模型是正确的。当负担在桥上移动了时，动人的负担模型的二种类型对反应范围有小差别，但是对反应阶段有某差别。当负担离开了时，moving-constant-force模型负担导致的动态回答的振幅比动人团的模型导致的那些大。有很多更多的差别当有更多的负担时。

简介：Tomeettherequirementsfortheaerodynamicperformanceandthrustforcedemandedinhypersonicmissions,theintegrationdesignoffuselageandenginemustbeconsideredforhypersonicvehiclewithascramjetengine.Theconfigurationofwaveriderisatypicalhypersonicvehicleshape,whosefore-bodycancompresstheflowinadvanceandprovideuniformflowfortheairintake,andwhoseaft-bodyisusedasanexpansionsurfaceofnozzle.Inthepresentpaper,anengineeringmethodisappliedtodefinetotalaerodynamiccharacteristicsofanapproximatewaveriderconfiguration.Afinitevolumemethodbasedonthecenterofgridisalsoemployedtonumericallyinvestigatetheoutflowpassthesameconfiguration.Theflowfielddetailsandtheaerodynamicchanacteristicsatgivenconditionsareobtained.Theevaluationforthisconfigurationmaybeusedasaguideforthehypersonicvehicleexperiment.

简介：混合粒子的行为用不同地有颜色却不同的相同玻璃范围在砍的小粒的流动被模仿，与五不同底部墙速度。由DEM模拟，稳固的部分，速度，速度变化和小粒的温度被测量。混合的层厚度与从用从当前的模拟大小获得的明显的自我散开系数的数据的一个简单散开方程的计算相比。计算和模拟结果显示出好协议，证明小粒的材料的混合过程通过散开机制发生了。

简介：Thehydrauliccharacteristicsattheconfluencereachofriverandlakeareinfluencedbymultiplefactorssuchasinflow,topographyandvegetationresistance,andareverycomplicated.Inthisarticle,theconfluencereachofYangtzeRiverandDong-tingLakeisselectedasaspecialexampleandahybridmodelisbuilttostudytheflowatthisconfluence,withtheconsiderationoftheinteractionsbetweenaquaticvegetationandflow.Validationtestsandcalculationsshowthatthemodeliseffectiveandhighlyaccurate.Thesimulationsshowthattheseparationleveeattheconfluencereachmaychangethedischargecapacityinthefloodplain,whichwouldbeenhancedintheupperreachofthelevee,hardlychangedinthemiddlereachandreducedatthelowerplace.Moreover,theseparationleveealsolimitsthewaterexchangebetweentheYangtzeRiverandDong-tingLake.

简介：Algalbloom,knownasredtide,hasoccurredfrequentlyintheBohaiSeainrecentdecadescausinggreateconomiclossestofisheriesaswellashavingsignificantadverseimpactontheenvironment.A3-DEco-Hydraulicmodelisdevelopedtosimulatetheexplosivepropagationofdiatomanddinoflagellateasafunctionoftheconcentrationofvariousnutrients,riverinflow,tide,temperature,wind,sunshineandrainfall.Themodelisintendedtoanswerthequestionsofhowthe1998BohaiSearedtideoccurred,andtoinvestigatehowenvironmentalfactors,suchastemperature,wind,rainfall,solarradiance,seacurrentsandnutrients,affectthealgalbloomprocess.Theparametersemployedinthemodelarecalibratedwiththedatacollectedintheperiods1982-1983and1992-1993.Resultsfromthemodelindicatethateutrophicationoftheseawateristhebasicconditionforalgalbloom,andthatthe1998redtidewastriggeredbytheabnormalwarmweatherinAugustandSeptember.