简介：在这研究，一条新分析途径被开发分析保守two-degree-of-freedom(TDOF)的免费非线性的颤动系统。这些系统的数学模型被秒顺序管理非线性的部分微分方程。非线性的微分方程被使用一些中间的变量变成一个单个方程。单个非线性的微分方程被使用Hamiltonian途径的第一份订单解决(哈)。不同参数，在系统的反应上有重要影响，被考虑并且讨论。一些比较被介绍验证在Hamiltonian途径和准确答案之间的结果。最大的相对错误是为颤动的大振幅的不到2.2124%。Hamiltonian途径的第一次重复完成很精确的结果，这被建立了，不要求任何小不安，并且能被用于大量非线性的问题。

简介：Nonlinearmetailogenicdynamicsisoneofthodifficultprob1emsthatcommonlyfacemoderncom-plcxscicnces.TheRussianfamousmetallogenjstA.D.Shcbeglov(1988)paidattentiontotheprob1emofnonlin-earmctal1ogenyandproposedthcconceptofnonlinearmcta11ogeny.HepointedoutthatthercjSane-cessityofamoredetailedandcomprchensive

简介：一个古典抑制矩阵的性能，从起始的结构的性质或当前的结构的性质的使用的构造任何一个，在自由(MDOF)的非线性的多重度的一步一步的解决方案，系统是评估的经分解。分析结果被数字例子证实。因而，一些结论从可能为实际应用被认为指南同样不平的这些分析结果被得出。从起始的结构的性质构造的一个古典抑制矩阵为实际应用是足够的，这被发现，自从它近似有由当前的结构的性质获得了的一样的抑制效果并且以计算是更有效的。

简介：Anonlinearshort-wave-averaged(surfbeat)modelispresented.ThemodelisbasedonthatofRoelvink(1993),butthenumericaltechniquesusedinthesolutionarebasedontheso-calledweighted-averagedflux(WAF)method(egWatsonetal.,1992),withtime-operatorsplittingusedforthetreatmentofsomeofthesourceterms.Thismethodallowsasmallnumberofcomputationalpointstobeused,andisparticularlyefficientinmodellingbreakinglongwaves.Theshort-wave(orprimary-wave)energyequationissolvedusingamoretraditionalLax-Wendrofftechnique.Resultsofvalidationindicatethatthemodelperformssatisfactorilyinmostrespects.

简介：Thespectralpropertiesofnonlineardragforcesofrandomwavesonverticalcircularcylindersareanalyzedinthispaperbymeansofnonlinearspectralanalysis.Theanalysisprovidesbasicparametersforestimationofthecharacteristicdragforces.Numericalcomputationisalsoperformedfortheinvestigationoftheeffectsofnonlinearityofthedragforces.TheresultsindicatethatthewavedragforcescalculatedbylinearwavetheoryarelargerthanthosecalculatedbythethirdorderStokeswavetheoryforgivenwaves.Thedifferencebetweenthemincreaseswithwaveheight.Thewavedragforcescalculatedbyuseoflinearapproximationareabout5％smallerthantheiractualvalueswhenmeasuredinthepeakvaluesofspectraldensities.Thiswillresultinasafetyproblemforthedesignofoffshorestructures.Therefore,thenonlineareffectofwavedragforcesshouldbetakenintoconsiderationindesignandapplicationofimportantoffshorestructures.

简介：Startingfromnonlinearequationsonthef-planecontainingfrictionaldissipationundertheBoussinesqapproximation,anewkindofgeneralizedenergyisproposedastheLyapunovfunction,andaveragesaretakenasanyfunctionsof(x,z)insteadofthecommonly-usedmeansofbilinearfunctionsof(x,z),therebyresultinginanewcriterionofgeneralizednonlinearsymmetricstability.Itshowsthatnotonlymustthedissipativecoefficientbegreaterthanacertaincriticalvaluebuttheinitialdisturbanceamplitudemustbesynchronouslysmallerthananothermarginalvalueaswell.Itfollowsthatthelatterimposesacrucialconstraintontheformer,thusleadingtothefactthatwhentheamplitudeisbiggercomparedtoanothercriticalvalue,generalizednonlinearsubcriticalsymmetricalinstabilitymayoccur.Thenewcriterioncontributesgreatlytotheimprovementofthepreviousresultsofitskind.

简介：尽管这被显示出HHT的实现--如果运动的方程被使用而不是差别方程评估下一步加速，一个方法能在假动态测试导致改进错误繁殖性质，当过去常解决一个非线性的系统时，这篇论文证明这个方法可能导致不稳定性。，它的无条件的稳定性为非线性的系统仅仅为线性有弹性的系统被验证，因为集中的步度是不到1，不稳定性发生。集中罐头的步度经常在假动态测试是不到1，是值得注意的，自从仅仅当集中的步度不管它的价值是否更大接近1时，一个会聚的答案被完成或不到1。因此，到假动态测试的这个计划的申请应该被禁止，自从不稳定性的可能性可能不正确地破坏一个标本。因而，由使用差别方程决定下一步加速的HHT-α方法的实现在假动态测试为使用被推荐。

简介：—Inthispaper,anonlinearmodelispresentedtodescribewavetransformationinshallowwat-erwiththezero-vorticityequationofwave-numbervectorandenergyconservationequation.Thenonlineareffectduetoanempiricaldispersionrelation(byHedges)iscomparedwiththatofDalrymple＇sdispersionrelation.Themodelistestedagainstthelaboratorymeasurementsforthecaseofasubmergedellipticalshoalonaslopebeach,wherebothrefractionanddiffractionaresignificant.Thecomputationre-sults,comparedwiththoseobtainedthroughlineardispersionrelation.showthatthenonlineareffectofwavetransformationinshallowwaterisimportant.Andtheempiricaldispersionrelationissuitableforre-searchingthenonlinearityofwaveinshallowwater.

简介：Inthispaper,thenonlinearcollapseoftheBOHAI-8pilefoundationjacketplatformhasbeenanalyzed.Theultimateloadandcollapseprocessoftwocomputationalmodelsofthestructurearegiven.Onemodelisoffixedsupportwhoselengthiseighttimesthepilelegdiameterandtheotherconsid-ersthenonlinearityofthesoil-pileinteraction.

简介：六个增强的具体框架与或没有石工技术填入在水平周期的负担下面被构造并且测试。所有六个框架有在列的横向的加强被没为可锻的框架遇见currentACI说明的矩形的箍在提供的相同细节。为比较目的，在三个这些框架的列是由carbon-fiber-reinforced-polymer(CFRP)的jacketed避免的表可能砍失败。Anonlinear闲差事分析，单个元素的力量变丑关系基于ACI318，FEMA356，和陈在被形成“s模型，为这些框架并且与测试结果相比被执行。这些框架的行为上的填入的失败机制和影响在学习被检验。从现在的分析的结论为infilled水泥框架大楼结构的评估和设计向结构的工程师提供珍贵信息。

简介：质地图像分割基于非线性的散开被介绍。质地的规模能在非线性的散开的过程期间被测量。有保存的边的一幅光滑的5隧道向量图象，紧张镇静，可伸缩，质地的取向想象，能被联合非线性的散开完成。一个多信道的统计区域活跃轮廓被采用分割这幅向量图象。因为参数不对不同质地图象敏感，方法能被看作一种无指导的分割。试验性的结果在质地图象的半自动的抽取显示出它的高效率。

简介：Forthesimulationofthenonlinearwavepropagationincoastalareaswithcomplexboundaries,anumericalmodelisdevelopedincurvilinearcoordinates.Inthemodel,theBoussinesq-typeequationsincludingthedissipationtermsareemployedasthegoverningequations.Inthepresentmodel,thedependentvariablesofthetransformedequationsarethefreesurfaceelevationandtheutilityvelocityvariables,insteadoftheusualprimitivevelocityvariables.TheintroductionofutilityvelocityvariableswhicharetheproductsofthecontravariantcomponentsofthevelocityvectorandtheJacobimatrixcanmakethetransformedequationsrelativelyconcise,thetreatmentoflateralboundaryconditionseasierandthedevelopmentoftheprogramsimpler.Thepredictor-correctormethodandfive-pointfinite-differenceschemeareemployedtodiscretizethetimederivativesandthespatialones,respectively.Thenumericalmodelistestedforthreecases.Itisfoundthatthenumericalresultsareingoodagreementwiththeanalyticalresultsandexperimentaldata.

简介：Basedonthe1stordercnoidalwavetheory,thewavediffractionaroundthepiergroupinshallowwaterisstudiedinthispaper.Theformulasforcalculatingthenonlinearwaveforcesarealsopresentedhere.Inordertoverifythetheoreticalresults,modeltestsareconductedinthewaveflumeinTheStateKeyLaboratoryofCoastalandOffshoreEngineeringlocatedinDalianUniversityofTechnology.TherangeofthewaveparametersintheexperimentsischaracteristicwaveperiodTg/d1/2=8.08-22.86,characteristicwaveheightH/d=0.10.45.Theresultsobtainedfromtheexperimentsagreewiththetheoreticalresultsquitewell.Itisshownthat,inshallowwaterthenonlinearwaveforcesactingonapiergrouparegreaterthanthosecalculatedbylinearwavetheory,thevalueofincrementinwaveforceincreaseswiththeincreasesofthenonlinearityofthewave.Inthewaverangestudiedinthispaper,thenonlinearwaveforcecanreachover4timestheforcecalculatecdbylinearwavetheory.Thus,itissuggestedthat,whenTg/d1/2>8,thewaveforceonthepiersinthepiergroupinshallowwatershouldbecalculatedbyusingthecnoidalwavetheory.

简介：Anonlineardynamicanalysismodelisestabilishedonthebasisof"lumpedmass"approach,whichtakestheinfluenceofthefluidflowwithinthepipeintoconsideration.Numericalresultsarecomparedwiththepublishedworks,andtheeffectsofinternalfluidflow,internalpressure,dyanmicsaswellasthenonlinearcharacteristicsonthebehaviorofflexiblerisersarediscussed.Fromthiswork,someusefulconclusionsaredrawn.

简介：Inthestratifiedatmosphereinwhichthemomentnondivergentapproximationwasapplied,introducingthenonlineartermbecauseofthenonhomogcneousspatialdistributionofdensityandassumingthesolutiontobeoftheformofprogressivewave,weobtainatwo-ordernonlinearsystem.Bymeansofthissystem,allresultswhichwerederivedbyLiuetal.(1984)wereobtained.Moreover,itcanbeprovedthatthereexistedperiodicsolutioninthenonlinearsystemswhenthereexistedperiodicsolutionintheone-orderapproxima-tionsystem,andsomemathematicproblemsarisingfromseriesexpansionwereavoided.Inthispaper,aseriesofapproximatesolutionsofnonlinearsystemisalsodiscussed.

简介：Thestudyinthispaperisfocusingontrajectoriesofparticlesintheirrotationalprogressivewaterwavescoexistingwithuniformcurrent.TheparametricequationsofparticletrajectoriesoverarangeoflevelsinaLagrangiantypeofdescriptionaredevelopedanalyticallyviatheEuler-Lagrangetransformation.TheLagrangianwaveperiodofparticlemotiondifferingfromtheEulerianwaveperiodandthemasstransportcanalsobeobtaineddirectly.Thethird-ordersolutionofparticletrajectoryexhibitsthattheydonotmoveinclosedorbitalmotionbutrepresentanetmovementthatdecreasesexponentiallywiththewaterdepth.Uniformcurrentisfoundtohavesignificanteffectonthetrajectoriesanddriftvelocityofgravitywaves.Overall,theinfluenceofincreaseduniformcurrentistoincreasetherelativehorizontaldistancetraveledbyaparticle,aswellasthemagnitudeofthetime-averageddriftvelocityonthefreesurface.Foradversecurrentcases,areversebehaviorisfound.Theobtainedthird-ordersolutionssatisfytheirrotationalconditioncontrastedtotheGerstnerwavesandareverifiedbyreducingtothoseoftwo-dimensionalgravitywavesinLagrangiancoordinates.

简介：Basedonthe1stordercnoidalwavetheory,thenonlinearwavediffractionaroundacircularcylinderinshallowwaterisstudiedinthispaper.Theequationofthewavesurfacearoundthecylinderisformulatedandbyusingthisformulathewavesurfaceelevationonthecylindersurfacecanbeobtained.Inthispaper,theformulaforcalculatingthecnoidalwaveforceonacircularcylinderisalsoderived.Forthewaveconditionswhichareoftenencounteredinpracticalengineeringdesigns,theratiosofthenonlinearwaveforcestothelinearwaveforcesarecalculated,andtheresultsareplottedinthispaperfordesignpurposes.Inordertoverifythetheoreticalresults,modeltestsareconducted.Aftercomparingthetestresultswiththetheoreticalones,itisconcludedthat,inshallowwater,forthecaseofTg/d1/2>8-10andH/d>0.3,thecnoidalwavetheoryshouldbeusedtocalculatethewaveactiononacylindricalpier.

简介：精确预言近海结构运动反应和伙伴绳索线紧张在技术应用和科学研究是重要的。在我们的学习，一个truss圆材平台，在墨西哥湾操作了，被一对内部地数字的代码夫妇数字地模仿并且分析。站台运动回答和联系绳索行紧张通过一个时间领域被计算并且调查非线性的联合动态分析。在模拟和相应领域大小之间的令人满意的同意在联系的将军，显示数字代码能被用来进行与它的绳索和起床人系统交往的truss圆材的时间域分析。基于在线性、非线性的结果之间的比较，在预言站台运动反应和绳索行紧张的非线性的相对重要性被估计并且介绍。通过联合并且伪静电干扰分析，在在预言系在的行紧张和站台运动的站台壳和绳索/起床人的系统之间的动态联合效果的重要性被确定。这些结果可以提供从属便于大规模的数字模拟和设计的必要信息近海结构。

简介：一种技术到的二重要延期为一个明确的假动态算法执行非线性的错误繁殖分析(Chang，2003)被介绍。一个人从给定的时间步扩大稳定性学习到一个完全的一步一步的集成过程。它是证明的经分解那条保证稳定性条件在每次，步导致全部一步一步的集成过程的稳定的计算。非线性的错误繁殖结果的另外的延期表演，它为自由(SDOF)的非线性的单个度被导出系统，能被用于自由(MDOF)的非线性的多重度系统。这个应用程序依赖于系统在的自然频率的决心每次走，自从所有数字性质和错误繁殖，在时间步的性质是仔细与这些频率有关。结果从非线性的步度被导出。非线性的即时度被介绍代替非线性的步度并且被显示在实践易用。延期能也被用于基于非线性，和因此步力量适当地被选择在测试以前执行假动态测试的一时间的即时度从一个SDOF系统导出的结果。

简介：BasedonBiot'sconsolidationtheory,atwo-dimensionalmodelforcomputationoftheseabedresponsetowavesispresentedwiththefiniteelementmethod.Numericalresultsfordifferentwaveconditionsareobtained,andtheeffectsofwavenon-linearityonthewave-inducedseabedresponseareexamined.Moreover,thewave-inducedmomentaryliquefactioninuniformandinhomogeneousseabedsisinvestigated.Itisshownthatthewavenon-linearityaffectsthedistributionofthewave-inducedporepressureandeffectivestresses,whiletheinfluenceofwavenon-linearityontheseabedliquefactionpotentialisnotsosignificant.