简介：Thesubsystemsynthesismethodhasbeendevelopedinordertoimprovecomputationalefficiencyforamultibodyvehicledynamicsmodel.Usingthesubsystemsynthesismethod,equationsofmotionofthebasebodyandeachsubsystemcanbesolvedseparately.Inthesubsystemsynthesismethod,variouscoordinatesystemscanbeusedandvariousintegrationmethodscanbeappliedineachsubsystem,aslongastheeffectivemassmatrixandtheeffectiveforcevectorareproperlyproduced.Inthispaper,comparativestudyhasbeencarriedoutforthesubsystemsynthesismethodwithCartesiancoordinatesandwithjointrelativecoordinates.Twodifferentintegrationmethodssuchasanexplicitintegratorandanexplicitimplicitintegratorareemployed.Inordertoseetheaccuracyandcomputationalefficiencyfromthedifferentmodelsbasedonthedifferentcoordinatesystemsanddifferentintegrationmethods,aroughterrainrunsimulationshasbeencarriedoutwitha6×6off-roadmultibodyvehiclemodel.

简介：二联合黑暗solitons在二部件的Bose-Einsteincondensate被考虑，并且他们的动力学被基于的变化途径调查renormalizedintegrals打手势。描述的方程areobtained的物理答案，和动态机制被执行搬到一个有效潜力的classicalparticle的一个坐标表明的静止状态回答。切换和thecoupled黑暗向量solitons的自我套住的动力学被原子人口transferringratio的进化讨论。

简介：Forthethree-dimensionalconvection-dominatedproblemofdynamicsoffluidsinporousmedia,thesecondorderupwindfinitedifferencefractionalstepsschemesapplicabletoparallelarithmeticareputforward.Fractionalstepstechniquesareneededtoconvertamulti-dimensionalproblemintoaseriesofsuccessiveone-dimensionalproblems.Sometechniques,suchascalculusofvariations,energymethod,multiplicativecommutationruleofdifferenceoperators,decompositionofhighorderdifferenceoperators,andthetheoryofpriorestimatesareadopted.Optimalorderestimatesarederivedtodeterminetheerrorinthesecondorderapproximatesolution.Thesemethodshavealreadybeenappliedtothenumericalsimulationofmigration-accumulationofoilresourcesandpredictingtheconsequencesofseawaterintrusionandprotectionprojects.

简介：Densegas-particleflowsareencounteredinavarietyofindustriallyimportantprocessesforlargescaleproductionoffuels,fertilizersandbasechemicals.Thescale-upoftheseprocessesisoftenproblematicandisrelatedtotheintrinsiccomplexitiesoftheseflowswhichareunfortunatelynotyetfullyunderstooddespitesignificanteffortsmadeinbothacademicandindustrialresearchlaboratories.Indensegas-particleflowsboth(effective)fluid-particleand(dissipative)particle-particleinteractionsneedtobeaccountedforbecausethesephenomenatoalargeextentgoverntheprevailingflowphenomena,i.e.theformationandevolutionofheterogeneousstructures.Thesestructureshavesignificantimpactonthequalityofthegas-solidcontactandasadirectconsequencethereofstronglyaffecttheperformanceoftheprocess.Duetotheinherentcomplexityofdensegas-particlesflows,wehaveadoptedamulti-scalemodelingapproachinwhichbothfluid-particleandparticle-particleinteractionscanbeproperlyaccountedfor.Theideaisessentiallythatfundamentalmodels,takingintoaccounttherelevantdetailsoffluid-particle(latticeBoltzmannmodel)andparticle-particle(discreteparticlemodel)interactions,areusedtodevelopclosurelawstofeedcontinuummodelswhichcanbeusedtocomputetheflowstructuresonamuchlarger(industrial)scale.Ourmulti-scaleapproach(seeFig.1)involvesthelatticeBoltzmannmodel,thediscreteparticlemodel,thecontinuummodelbasedonthekinetictheoryofgranularflowandthediscretebubblemodel.Inthispaperwegiveanoverviewofthemulti-scalemodelingstrategy,accompaniedbyillustrativecomputationalresultsforbubbleformation.Inaddition,areaswhichneedsubstantialfurtherattentionwillbehighlighted.

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简介：Basedontheporousmediatheoryandbytakingintoaccounttheeffectsoftheporefluidviscidity,energyexchangesduetotheadditionalthermalconductionandconvectionbetweensolidandfluidphases,amathematicalmodelforthedynamic-thermo-hydro-mechanicalcouplingofanon-localthermalequilibriumfluid-saturatedporousmedium,inwhichthetwoconstituentsareassumedtobeincompressibleandimmiscible,isestablishedundertheassumptionofsmalldeformationofthesolidphase,smallvelocityofthefluidphaseandsmalltemperaturechangesofthetwoconstituents.Themathematicalmodelofalocalthermalequilibriumfluid-saturatedporousmediumcanbeobtaineddirectlyfromtheaboveone.SeveralGurtin-typevariationalprinciples,especiallyHu-Washizutypevariationalprinciples,fortheinitialboundaryvalueproblemsofdynamicandquasi-staticresponsesarepresented.Itshouldbepointedoutthatthesevariationalprinciplescanbedegeneratedeasilyintothecaseofisothermalincompressiblefluid-saturatedelasticporousmedia,whichhavebeendiscussedpreviously.

简介：Thecalculationofsettlingspeedofcoarseparticlesisfirstlyaddressed,withacceleratedStokesiandynamicswithoutadjustableparameters,inwhichfarfieldforceactingontheparticleinsteadofparticlevelocityischosenasdependentvariablestoconsiderinter-particlehydrodynamicinteractions.Thesedimentationofasimplecubicarrayofsphericalparticlesissimulatedandcomparedtotheresultsavailabletoverifyandvalidatethenumericalcodeandcomputationalscheme.TheimprovedmethodkeepsthesamecomputationalcostoftheorderO(NlogN)asusualacceleratedStokesiandynamicsdoes.Then,morerealisticrandomsuspensionsedimentationisinvestigatedwiththehelpofMontCarlomethod.Thecomputationalresultsagreewellwithexperimentalfitting.Finally,thesedimentationoffinercohesiveparticle,whichisoftenobservedinestuaryenvironment,ispresentedasafurtherapplicationincoastalengineering.

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简介：Thecarbon-13spin-spinrelaxationtimesoffluorine-containingionomersaremeasuredandmotionalcorrelationtimesτ_oandτ_darecalculatedbyusingVJGMmodel.Theresultsshowthatthemotionsofpolymermainchaininionomersbecomemoredifficultwithincreasingofionizationdegreeandcontentsoffunctionalgroup,anddependonthefinestructuresandstabilityofionicmicrodomains.

简介：重氢氰化物的高度激动的颤动的混乱动力学被二条独立途径探索：(1)Lyapunov分析基于为层次的古典阶段空间，并且(2)狄克逊剧降分析基于摆钟动力学和使量子化的层次的概念。结果证明在这二个算法之间有明显的关联。我们也建议剧降能为动态混乱的度作为一项质的措施被带的二附近的狄克逊之间的精力差别相互。

简介：Multipleexcitongeneration(MEG)dynamicsincolloidalPbSquantumdots(QDs)characterizedwithanimprovedtransientgrating(TG)techniquewillbereported.Onlyonepeaksoonafteropticalabsorptionandafastdecaywithin1pscanbeobservedintheTGkineticswhenthephotonenergyofthepumplighthνissmallerthan2.7Eg(Eg:bandgapbetweenLUMOandHOMOintheQDs),whichcorrespondstohotcarriercooling.Whenhνisgreaterthan2.7Eg,however,aftertheinitialpeak,theTGsignaldecreasesfirstandsoonincreases,andthenanewpeakappearsatabout2to3ps.TheinitialpeakandthenewpeakcorrespondtohotcarriersatthehigherexcitedstateandMEGatthelowestexcitedstate,respectively.Byproposingatheoreticalmodel,wecancalculatethehotcarriercoolingtimeconstantandMEGoccurrencetimeconstantquantitatively.WhenMEGdoesnothappenforhνsmallerthan2.7Eg,hotcarriercoolswithatimeconstantof400fs.WhenMEGoccursforhνlargerthan2.7Eg,hotcarriercoolswithatimeconstantassmallas200fs,whileMEGoccurswithatimeconstantof600fs.ThedetailedhotcarriercoolingandMEGoccurrencedynamicscharacterizedinthisworkwouldshedlightonthefurtherunderstandingofMEGmechanismofvarioustypeofsemiconductorQDs.

简介：通过吝啬地的近似，Gaussian近似，不安扩大，和一个3理论的地理论上的重正常化组分析的详细研究，我们证明不稳定性修理了理论的点，和他们的联系不稳定性代表，与可伸缩和一阶的阶段转变在一个地驱动的分级的4模型展出的普遍性行为相当可能相关，在它的批评温度和近的th下面放大并且领先修正到可伸缩的Finitetime被考虑。我们也证明一阶的阶段转变的不稳定性代表Yang庇护边奇特等价于那些，并且采用后者改进我们前者的估计。结果与存在数字结果同意很好。

简介：ConsidertheCauchyproblemsforann-dimensionalnonlinearsystemoffluiddynamicsequations.ThemainpurposeofthispaperistoimprovetheFouriersplittingmethodtoaccomplishthedecayestimateswithsharpratesoftheglobalweaksolutionsoftheCauchyproblems.WewillcoupletogethertheelementaryuniformenergyestimatesoftheglobalweaksolutionsandawellknownGronwall'sinequalitytoimprovetheFouriersplittingmethod.ThismethodwasinitiatedbyMariaSchonbekinthe1980'stostudytheoptimallongtimeasymptoticbehavioursoftheglobalweaksolutionsofthenonlinearsystemoffluiddynamicsequations.Asapplications,thedecayestimateswithsharpratesoftheglobalweaksolutionsoftheCauchyproblemsforn-dimensionalincompressibleNavier-Stokesequations,forthen-dimensionalmagnetohydrodynamicsequationsandformanyotherveryinterestingnonlinearevolutionequationswithdissipationscanbeestablished.

简介：在这篇论文，有连续分布式的延期的一个非线性的非自治的食肉动物猎物分散模型被学习，在所有参数是时间依赖者的地方。在由n补丁组成的这个系统，猎物种类能在n补丁之中分散，但是食肉动物种类被限制到一个补丁；不能分散。系统在任何分散率效果下面是一致地坚持的，这被证明。而且，一些足够的条件为系统的一个唯一的几乎周期的答案的存在被建立。例子证明在纸的标准是新的，一般；容易可证实。

简介：Globalbifurcationsandmulti-pulsechaoticdynamicsforasimplysupportedrectangularthinplatearestudiedbytheextendedMelnikovmethod.Therectangularthinplateissubjecttotransversalandin-planeexcitation.Atwo-degree-of-freedomnonlinearnonautonomoussystemgoverningequationsofmotionfortherectangularthinplateisderivedbythevonKarmantypeequationandtheGalerkinapproach.Aone-tooneinternalresonanceisconsidered.Anaveragedequationisobtainedwithamulti-scalemethod.Aftertransformingtheaveragedequationintoastandardform,theextendedMelnikovmethodisusedtoshowtheexistenceofmulti-pulsechaoticdynamics,whichcanbeusedtoexplainthemechanismofmodalinteractionsofthinplates.AmethodforcalculatingtheMelnikovfunctionisgivenwithoutanexplicitanalyticalexpressionofhomoclinicorbits.Furthermore,restrictionsonthedamping,excitation,anddetuningparametersareobtained,underwhichthemulti-pulsechaoticdynamicsisexpected.Theresultsofnumericalsimulationsarealsogiventoindicatetheexistenceofsmallamplitudemulti-pulsechaoticresponsesfortherectangularthinplate.

简介：Inthisstudy,weevaluatethevaluesoflatticethermalconductivityκLoftypeIIGeclathrate(Ge34)anddiamondphaseGecrystal(d-Ge)withtheequilibriummoleculardynamics(EMD)methodandtheSlack'sequation.ThekeyparametersoftheSlack'sequationarederivedfromthethermodynamicpropertiesobtainedfromthelatticedynamics(LD)calculations.TheempiricalTersoff'spotentialisusedinbothEMDandLDsimulations.Thethermalconductivitiesofd-Gecalculatedbybothmethodsareinaccordancewiththeexperimentalvalues.ThepredictionsoftheSlack'sequationareconsistentwiththeEMDresultsabove250KforbothGe34andd-Ge.Inatemperaturerangeof200-1000K,theκLvalueofd-GeisaboutseveraltimeslargerthanthatofGe34.

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简介：Thechaindynamicsofapairofdiblockpoly(styrene-b-butadiene)(PS210-b-PB960)andtriblockpoly(styrene-b-butadiene-b-styrene)(PS200-b-PB1815-b-PS200)copolymersinbothdiluteandsemidilutetoluenesolutionshasbeencomparativelystudiedbydynamiclaserlightscattering.Asexpected,themutualdiffusionofindividualchainchangesintoafastcooperativediffusionofthechainsegments('blobs')betweentwoneighboringentanglementpointsforboththecopolymersasthesolutionchangesfromdilutetosemidilute.Furtherincreasesoftheconcentrationleadtoasecondslowrelaxationmode.Forthetriblockchains,thereexistsanadditionalmiddlerelaxationbetweenthefastandtheslowmodes.with0.33＜α＜0.44,muchsmallerthan0.75predictedor0.72observedforlinearhomopolymerchainsingoodsolvent.ItimpliesthatthesolventqualityoftolueneforPBmightnotbeasgoodasthatforPS.Duetosuchadifferenceinsolubility,itisreasonabletospeculatethatthePBandPSblocksaretransientlysegregatedinsemidilutesolution.TherelaxationofthesetransientPBandPSricherdomainsleadstotheobservedslowrelaxation.Suchaspeculationissupportedbytheappearanceofanadditionalslowrelaxationmodeinthestudyofpolyisoprene-b-polystyrene-b-polyisopreneinsemidilutesolutionincyclohexane,anon-selectivesolvent,inwhichwealternatedthesolubilitydifferencebyavariationofthesolutiontemperature.