简介：AmeshlessapproachtoanalysisofarbitraryKirchhoffplatesbythelocalboundaryintegralequation(LBIE)methodispresented.Themethodcombinestheadvantageousfeaturesofallthethreemeth-ods:theGalerkinfiniteelementmethod(GFEM),theboundaryelementmethod(BEM)andtheelement-freeGalerkinmethod(EFGM).Itisatrulymeshlessmethod,whichmeansthatthediscretizationisinde-pendentofgeometricsubdivisionintoelementsorcells,butisonlybasedonasetofnodes(orderedorscat-tered)overadomaininquestion.Itinvolvesonlyboundaryintegration,however,overalocalboundarycen-teredatthenodeinquestion;Itposesnodifficultiesinsatisfyingtheessentialboundaryconditionswhileleadingtobandedandsparsesystemmatricesusingthemovingleastsquare(MLS)approximations.Itisshownthathighaccuracycanbeachievedforarbitrarygeometriesforclampedandsimply-supportededgeconditions.Themethodisfoundtobesimple,efficient,andattractive.

简介：Anewmethodforestimationtheboundsofeigenvaluesispresented.InordertoshowthatthemethodproposeisaseffectiveasQiu’s,anundampingspring-masssystemwith5nodesand5degreesoffreedomisgiven.Toillustratethatthepresentmethodcanbeappliedtostructureswhichcannotbetreatedbynon-negativedecompsition,aplandframewith202nodesand357beamelementsisgiven.TheresultsshowthatthepresentmethodiseffectiveforestimatingtheboundsofeigenvaluesandismorecommonthanQiu’s.

简介：我们在场为绝缘的弹性体(DE)的一个有限元素方法变换器基于DE的非线性的域理论。方法在商业有限元素软件ABAQUS被实现，它提供一个大图书馆描述有限弹性的功能。这个方法能被用来与复杂配置并且在不同类的变丑下面解决DE变换器的机电的联合问题。

简介：Aconcurrentmultiscalemethodisdevelopedforsimulatingquasi-staticcrackpropagationinwhichthefailureprocessesoccurinonlyasmallportionofthestructure.Forthispurpose,amultiscalemodelisadoptedandbothscalesarediscretizedwithfinite-elementmeshes.Theextendedfiniteelementmethodisemployedtotakeintoaccountthepropagationofdiscontinuitiesonthefine-scalesubregions.Atthesametime,fortheothersubregions,thecoarse-scalemeshisemployedandisresolvedbyusingtheextendedmultiscalefiniteelementmethod.Severalrepresentativenumericalexamplesaregiventoverifythevalidityofthemethod.

简介：ExplicitexpressionsofMori-Tanaka’stensorforatransverselyisotropicfiberreinforcedUDcompositearepresented.Closed-formformulaefortheeffectiveelasticpropertiesofthecompositeareobtained.Ina3Dsense,theresultingcompliancetensorofthecompositeissymmetric.Nevertheless,the2DcompliancetensorbasedonadeterioratedMori-Tanaka’stensorisnotsymmetric.Noristhecompliancetensordefineduponadeteriorated2DEshelby’stensor.Thein-planeeffectiveelasticpropertiesgivenbythosethreeapproachesaredifferent.AdetailedcomparisonbetweenthepredictedresultsobtainedfromthoseapproacheswithexperimentaldataavailableforanumberofUDcompositesismade.更多还原

简介：提高的不一致的合理B花键(NURBS)放大了边界在有修改精确集成方法的联合的有限元素方法在这份报纸为短暂的热传导问题被建议。放大边界有限元素方法是一种半分析的技术，它削弱管理沿着环绕的方向的微分方程并且在光线的方向解决那些经分解。在这个方法，仅仅边界是在没有要求的基本答案在一个导致空间尺寸的减小的有限元素意义的discretized。但在复杂几何学的情况下，元素的一个巨大的数字通常被要求适当地接近，领域和弄歪的网孔的准确形状在常规有限元素途径经常是不可避免的，它导致精确性的巨大的计算努力和损失。NURBS由于它的灵活性是在CAD工业的最流行的数学工具适合任何自由形态的形状。在建议方法论，问题领域的任意的弄弯的边界确切与NURBS基础函数被代表，当边界的直部分是由常规Lagrange形状函数的discretized时。两isogeometric分析和放大边界的概念有限元素方法被联合形成短暂的热传导分析的管理方程，答案用修改精确集成方法被获得。僵硬矩阵从一个标准二次的特征值问题被获得，集体矩阵从低频率的扩大是坚定的。最后，管理方程成为一阶的平常的微分方程的一个系统，时间域反应被修改精确集成方法数字地解决。建议方法的精确性和稳定性被数字例子表明处理短暂的热传导问题。

简介：Basedonalevelsetmodelandthehomogenizationtheory,anoptimizationalgorithmforfindingtheoptimalconfigurationofthemicrostructurewithspecifiedpropertiesisproposed,whichextendscurrentresearchonthelevelsetmethodforstructuretopologyoptimization.ThemethodproposedemploysalevelsetmodeltoimplicitlydescribethematerialinterfacesofthemicrostructureandaHamilton-Jacobiequationtocontinuouslyevolvethematerialinterfacesuntilanoptimaldesignisachieved.Meanwhile,themovingvelocitiesoflevelsetareobtainedbyconductingsensitivityanalysisandgradientprojection.Besides,howtohandletheviolatedconstraintsisalsodiscussedinthelevelsetmethodfortopologicaloptimization,andareturn-mappingalgorithmisconstructed.Numericalexamplesshowthatthemethodexhibitsoutstandingflexibilityofhandlingtopologicalchangesandfidelityofmaterialinterfacerepresentationascomparedwithotherconventionalmethodsinliteratures.

简介：Anintervaloptimizationmethodforthedynamicresponseofstructureswithintervalparametersispresented.Thematricesofstructureswithintervalparametersaregiven.Combiningtheintervalextensionwiththeperturbation,themethodforintervaldynamicresponseanalysisisderived.Theintervaloptimizationproblemistransformedintoacorrespondingdeterministicone.Becausethemeanvaluesandtheuncertaintiesoftheintervalparameterscanbeelecteddesignvariables,moreinformationoftheoptimizationresultscanbeobtainedbythepresentmethodthanthatobtainedbythedeterministicone.Thepresentmethodisimplementedforatrussstructure.Thenumericalresultsshowthatthemethodiseffective.

简介：quasistatic一致设计被做为不平表面的粘附描绘有效连贯的地区行为。在一致设计的上下文，为一个不平的接口的一致连贯的地区(HCZ)的拖拉对分离关系能在显微镜的粘附和decohesion进程期间由于不稳定性是高度摆动的。不稳定性被发现不仅个别地而且一起发生在粘合剂之中微粗糙的接触，导致广泛的精力驱散。基于HCZ关系的行为，为在不平表面的粘附描述导致不稳定性的精力驱散的一个框架被建议阐明明显的接口粘附上的粗糙的效果。二个非维的参数，与粗糙形态学有关的伪和与aw分发有关的n，被识别为控制精力驱散很关键。为浅粗糙和强壮的内在的粘合剂力量的一个接口，如果我们使它更不平，接口粘附能更强壮(减少伪)或降低它的aw密度(增加的n)。HCZ设计方法能潜在地被扩大并且采用了为与多尺度的浅粗糙设计表面从内在的粘附性质衔接明显的粘附。

简介：Thepurposeofthisworkistoinvestigatethedynamicfracturepropertiesofglassypolycarbonate(PC)withdiferentagingtimes.Theopticalmethodofcausticsisadoptedinwhichtheshadowspotpatternsarerecordedbyahighspeedcameraduringthedynamicfractureprocess.Then,thedynamiccrackpropagation,thestressintensityfactor(SIF)andthedynamicfracturetoughnessofagedPCareobtainedthroughananalysisofthecharacteristicsizeofcausticpattern.Moreover,bycombiningwiththeinvestigationofthefracturesurfaceandtheenergyreleaserateanalysis,theinfluenceofagingtimeonthedynamicfracturebehaviorisdiscussed.ResultsshowthatthedynamicfracturetoughnessandcriticalenergyreleaserateofPCdecreaseswithagingtimeforshortagingtimes,whereastheyhavelittlechangeorevenincreaseforlongeragingtimes.Therefore,agingmodifiesthemechanicalpropertiesespeciallythedynamicfracturepropertiesofPCnonlinearly,notlinearlyasgenerallythoughtof.

简介：这份报纸试图借助于homogenization方法决定连接岩石群众的力量性质。为了反映连接岩石的微观结构，集中，代表性的元素体积(加快)被选择。假设僵硬、非常塑料并且利用Mohr库仑为岩石和关节产出标准，一个上面的界限限制分析方法基于homogenization理论被建议。由使用有限元素方法和Goodman联合元素，有平等限制的非线性的数学编程被提出，它能被一个直接反复的算法解决。数字结果证明连接岩石群众的力量表现有不同联合方向的anisotropy。这个方法为连接岩石群众的力量分析介绍一个有效工具。

简介：Amathematicalprogramisproposedforthehighlynonlinearprobleminvolvingfrictionalcontact.Aprogram-patternusingthefastmultipoleboundaryelementmethod(FMBEM)isgivenfor3-DelasticcontactwithfrictiontoreplacetheMonteCarlomethod.Anewoptimizedgeneralizedminimalresidual(GMRES)algorithmispresented.Numericalexamplesdemonstratethevalidityoftheprogram-patternoptimizationmodelfornode-to-surfacecontactwithfriction.TheGMRESalgorithmgreatlyimprovesthecomputationalefficiency.

简介：AnumericalanalysiswascarriedouttostudythemovingboundaryprobleminthephysicalprocessofpulsedNd-YAGlasersurfacemeltingpriortovaporization.Theenthalpymethodwasappliedtosolvethistwo-phaseaxisymmetricalmehingproblem.Computationalresultsoftemperaturefieldswereobtained,whichprovideusefulinformationtopracticallairtreatmentprocessing.Thevalidityofenthalpymethodinsolvingsuchproblemsispresented.

简介：为有弹性的模量调整的新策略基于忍受比率(EBR)的元素被建议，并且有弹性的模量减小方法(EMRM)为框架结构的限制负担评估被建议。EBR被定义采用概括收益标准，并且参考书EBR被在结构介绍极值和EBR的一致性的度决定。在有比参考书大的EBR的元素的有弹性的模量一个人基于线性有弹性的有限元素分析和种类精力的平衡被减少。框架结构的限制负担降低界限被分析，数字例子表明建议方法的灵活性，精确性和效率。

简介：这篇论文处理我击碎的模式在用精细的数字波纹技术的飞机压力状况下面的一张击碎的橡胶表的问题。通过自动化穗分析的四个转移stepphase方法，在Cartesiancoordinate系统的排水量地被给。由并列变换的方程，在极的坐标系统的光线、圆形的排水量分布被获得。裂缝尖端附近的排水量isolinedistributions和排水量向量分布被讨论。裂缝尖端附近的strainisoline分布也在这篇论文被分析。最后，分发近为机械域裁定裂缝尖端与部门部门方法被讨论。

简介：Anumericalmethodforsimulatingnonlinearfluid-rigidstructureinteractionproblemsisdeveloped.Thestructureisassumedtoundergolargerigidbodymotionsandthefluidflowisgovernedbynonlinear,viscousornon-viscous,fieldequationswithnonlinearboundaryconditionsappliedtothefreesurfaceandfluid-solidinteractioninterfaces.AnArbitrary-Lagrangian-Eulerian(ALE)meshsystemisusedtoconstructthenumericalmodel.Amulti-blocknumericalschemeofstudyisadoptedallowingfortherelativemotionbetweenmovingoversetgrids,whichareindependentofoneanother.Thisprovidesaconvenientmethodtoovercomethedifficultiesinmatchingfluidmesheswithlargesolidmotions.Nonlinearnumericalequationsdescribingnonlinearfluid-solidinteractiondynamicsarederivedthroughanumericaldiscretizationschemeofstudy.Acouplingiterationprocessisusedtosolvethesenumericalequations.Numericalexamplesarepresentedtodemonstrateapplicationsofthemodeldeveloped.

简介：TheSelf-SimilarCrackExpansion(SSCE)methodisproposedtoevaluatestressintensi-tyfactorsatcracktips,wherebystressintensityfactorsofacrackcanbedeterminedbythecrackopeningdisplacementoverthecrack,notjustbythelocaldisplacementaroundthecracktip.Thecrackexpansionrateisestimatedbytakingadvantageofthecrackself-similarity.Therefore,theaccuracyofthecalculationisimproved.Thesingularintegralsoncracktipelementsarealsoanalyzedandarepre-ciselyevaluatedintermsofaspecialintegralanalysis.Combinationofthesetwotechniquesgreatlyin-creasestheaccuracyinestimatingthestressdistributionaroundthecracktip.Avarietyoftwo-dimen-sionalcracks,suchassubsurfacecracks,edgecracks,andtheirinteractionsarecalculatedintermsoftheself-similarexpansionrate.Solutionsaresatisfiedwitherrorslessthan0.5%ascomparedwiththeanalyticalsolutions.Basedonthecalculationsofthecrackinteractions,atheoryforcrackinteractionsisproposedsuchthatforagroupofalignedcracksthesummationofthesquareofSIFsattherighttipsofcracksisalwaysequaltothatatthelefttipsofcracks.ThistheorywasprovedbythemehtodofSelf-SimilarCrackExpansioninthispaper.

简介：Theboundaryelementmethodisusedforthemodalanalysisoffreevibrationof2-Dcompositestructuresinthispaper.Sincetheparticularsolutionmethodisusedtotreatthetermsofbodyforces(inertialforces)intheequationofmotion,onlystaticfundamentalsolutionsareneededinsolvingtheproblem.Foranisotropiccantileverbeam,thenumericalresultsobtainedbyusingtheBEMpresentedinthispaperareingoodagreement,withthoseofusingFEMorotherBEM,butthisBEMcanalsobeusedtoanalyzeproblemsforanisotropicmaterials.Forsimplysupportedcompositelaminatedbeams,thecomparisonsofthenumericalresultsobtainedbythismethodwiththeanalyticalresultsobtainedby1-Dlaminatedbeamtheoryindicatethatiftheratiooflength/thicknessisgreaterthan20,theresultsofthetwomethodsareingoodagreement,butiftheratiooflength/thicknessislessthan20,bigerrorswilloccurfor1-Dlaminatedbeamtheory.

简介：Thenon-probabilisticreliabilityinhigherdimensionalsituationscannotbecalculatedefficientlyusingtraditionalmethods,whicheitherrequirealargeamountofcalculationorcausesignificanterror.Inthisstudy,anefficientcomputationalmethodisproposedforthecalculationofnon-probabilisticreliabilitybasedonthevolumeratiotheory,specificallyforlinearstructuralsystems.Thecommonexpressionfornon-probabilisticreliabilityisobtainedthroughformuladerivationwiththeamountofcomputationconsiderablyreduced.Thecompatibilitybetweennon-probabilisticandprobabilisticsafetymeasuresisdemonstratedthroughtheMonteCarlosimulation.Thehighefficiencyofthepresentedmethodisverifiedbyseveralnumericalexamples.

简介：Thispaperappliesthestochasticfiniteelementmethodtoanalysethestatisticsofstressesinearthdamsandassessthesafetyandreliabilityofthedams.Formulationsofthestochasticfiniteelementmethodarebrieflyreviewedandtheprocedureforassessingdam’sstrengthandstabilityisdescribed.Asanexample,adetailedanalysisforanactualdam-Nululindamisperformed.Apracticalmethodforstudyingbuilt-damsbasedontheprototypeobservationdataisdescribed.