简介：这篇论文介绍各向异性的损坏理论的应用程序给形成A12024T3铝合金表的限制图的学习。在限制铝板结构的紧张的预言，一个有限元素房间模型被构造了。房间模型由二个阶段，铝合金矩阵和金属间化合的簇组成。铝合金矩阵的材料行为与充分联合的elasto塑料的损坏被描述组成的方程。金属间化合的簇被假定有弹性、易碎。由改变拉长的比率，在二轴的拉长下面的表的限制紧张被使用建议的necking标准预言了。预言在对试验性的调查结果的好同意。而且，有限元素房间模型能为理解铝合金的显微镜的损坏机制提供信息。如果材料损坏的效果在形成学习的表金属被忽略，限制紧张的在评价上可以结果。

简介：Thenew-typetractionboundaryintegralequationsdevelopedbyHuandwithnohypersingularintegralareappliedtoanalysisof3Dfinitecrackedbodies.Anumericalalgorithmforgeneral3Dproblemsandasemi-analyticaloneforaxisymmetricproblemsarepresented.Someexamplesofthickplatesandcylindricalcolumnsincludingpenny-shapedcrack(s),andrectangularplatesincludinganellipticalcracknormaltothesurfaceareanalyzed.Thecomparisonbetweenpresentresultsandthoseinliteratureshowsthehighaccuracyandeffectivenessofthepresentmethod.

简介：Theboundaryelementmethodforthemodalanalysisoffreevibrationfor3-Danisotropicstructuresusingparticularsolutionshasbeendeveloped.Thecompletepolynomialsofordertwoareusedtoconstructtheparticularsolutionsforgeneralanisotropicmaterials.Thenumericalresultsfor3-Dfreevibra-tionanalysisofanisotropiecantileverbeambythemethodpresentedisingoodagreementwiththeresultsus-ingtheRitztechnique.Foranisotropicmaterials,thenumericalresultscalculatedfromtheproposedmethodareingoodagreementwiththeresultsfromMSC.NASTRAN.

简介：ThisinvestigationpresentstheGreenfunctionsforadecagonalquasicrystallinematerialwithaparabolicboundarysubjecttoalineforceandalinedislocationbymeansofthecomplexvariablemethod.ThesurfaceGreenfunctionsaretreatedasaspecialcase,andtheexplicitexpressionsofdisplacementsandhoopstressattheparabolicboundaryarealsogiven.Finally,thestressesanddisplacementsinducedbyaphononlineforceactingattheoriginofthelowerhalf-spacearepresented.

简介：Themillrollerbeatingismadeupofaninternalring,middlerollsandanexternalring,theanalysisofwhiehisamulti-bodiescontactproblem.Inthispaper,basedonthethree-dimensionalelasticcontactBEMwithoutfriction,andusingthestructuralcharacteristicsofrollerbearings,middlerollsarede-scribedbyelasticplateunitsofdifferentshapes,whichisplacedontheinternalring.Thediscontinuoustractionproblemofthecontactelementcanbedealtwithbythetractionsub-elementmethod.Thereforethecontactproblemcanbechangedfroinoneofmulti-bodiestooneoftwo-bodies.Asanelasticdeformationoftheplateelement,itcanbecalculatedbyanelasticcontactformulaandisregardedananequivalentgaptobeputintothetotalmatrixequality.Theface-to-facecontactconditionofdisplacementandtractionontheelementwillnerveastheconvergencejudgingcondition.Soconvergencesolutioncanbeobtainedbeforeanygeometryinconsistentonthecontactelementmaytakeplace.Therefore,thethree-dimensionaldistributionofloadofthemillrollerbearingcanbeachieved,Ithasbeenprovedthatthecalculatingmodelofthismethodisvisualizedandsimple,haslastconvergencesolutionandhigheraccuracy,makingitaneffectivenumericalmethodofdesigningandanalyzingloadcharacteristicsofthemillrollerbearing.

简介：Solutionstoapiezoelectrichalf-planewithafixedconductorsurfaceelectrodesubjectedtotwogeneralizedsingularities(linedislocationand/orlineforceandfreecharge)arepresented.Coulombforcesactingonthesingularitiesduetotheboundarypolarizationchargesofmediumandtheinductioncharg-esofconductorelectrodeareanalyzedindetail.Theinteractionbetweenthetwosingularitiesisalsoanalyzednumerically.ResultsshowthatCoulombforceswillbecomeimportantasthefreechargeapproachestheboundaryortwosingularitiesmoveclosely.

简介：为angle-interlockwoven的有弹性的行为分析的一个微机械模型陶器的composites在这篇论文被建议。这个模型由在空间，在邻近的纱之间的洞和纱的实际剖面图几何学认为纤维是波动和连续性考虑实际织物结构。基于laminate理论，编织的3D角度联锁的有弹性的性质陶器的composites被预言。交叉的纬的不同数字几乎有一样的有弹性的moduli。陶器的矩阵的厚度在有弹性的moduli上有小效果。当波动比率增加纵的模量减少和另外的幼仔的moduli增加时。在理论预言和试验性的结果之间的好同意在分析编织的3Dangle-interlock的有弹性的性质表明建议模型的可行性陶器的composites。这篇论文的结果验证分析聚酯矩阵composites的方法对编织陶器的composites合适的事实。

简介：thehydroxya-patite粒子的机械性质上的水吸着的损坏效果增强了Bis-GMA/TEGDMA共聚物(HA/Bis-GMA/TEGDMA)用3D被预言了有限房间模型。聚合物矩阵上的可塑剂效果被看作它的幼仔的模量的一个变化。三个不同房间模型被用来决定在debondingdamage上改变粒子内容，分裂期间力量和潮湿集中的影响。压力分发模式被检验了，压力转移模式澄清了。幼仔Bis-GMA/TEGDMA的模量和破裂力量合成也有或没有损坏的考虑用模型被预言。有thedebonding损坏的考虑的以前的结果在对存在文学的好同意是试验性的数据。我们的建议模型和一条其他的途径的防护效果被讨论。FCC房间模型也被扩大了预言批评负担为损坏并且undamaged合成题目到3点曲折测试。

简介：PhaseShiftingAndLogicalMoire(PSALM)isakindofcomputerimageprocessingmethodwhichcanbeusedinphasemeasurementandtoobtaintheshape,deformationandstraindistributionofanobject.Thispaperpresentsthestructureandworkingprocedureofa2DphasemeasurementPSALM2Dprogramanditsapplication.Whenanalyzingmoireinterferometricfringes,wecanobtain2Ddistributionofdisplacementandstrain.Whenitisusedinreflectionmoirewecanmeasuretheslopeofaspecimen.SatisfactoryvisualizationandquantitativeresultsaregivenbyPSALM2D.

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

简介：在这篇论文，为orthotropic板的飞机裂缝问题的压力紧张因素的评估相等参数用一个分数维的二水平的有限元素方法(F2LFEM)被调查。一个orthotropic裂缝问题的一般答案被与各向同性的裂缝问题吸收这个问题获得，并且在F2LFEM作为全球插值功能被采用。在裂缝板的裂缝尖端的邻居，分数维的几何学概念被介绍完成有类似比率的类似的网孔不到一个并且产生一个无穷小的网孔以便在二邻近的层的僵硬矩阵之间的关系是相等的。在裂缝尖端附近的自由的很多度被转变到概括坐标的一个小集合。数字例子证明这个方法在评估压力紧张因素(SIF)有效、精确。

简介：Thenonlinearbehaviorofacantileveredfluidconveyingpipesubjectedtoprincipalparametricandinternalresonancesisinvestigatedinthispaper.Theflowvelocityisdividedintoconstantandsinusoidaiparts.Thevelocityvalueoftheconstantpartissoadjustedsuchthatthesystemexhibits3:1internalresonancesforthefirsttwomodes.Themethodofmultiplescalesisemployedtoobtaintheresponseofthesystemandasetoffourfirst-ordernonlinearordinary-differentialequationsforgoverningtheamplitudeoftheresponse.TheeigenvaluesoftheJacobianmatrixareusedtoassessthestabilityoftheequilibriumsolutionswithvaryingparameters.Thecodimension2derivedfromthedouble-zeroeigenvaiuesisanalyzedindetail.Theresultsshowthattheresponseamplitudemayundergosaddle-node,pitchfork,Hopf,homoclinicloopandperiod-doublingbifurcationsdependingonthefrequencyandamplitudeofthesinusoidalflow.Whenthefrequencyofthesinusoidalflowequalsexactlyhalfofthefirst-modefrequency,thesystemhasaroutetochaosbyperiod-doublingbifurcationandthenreturnstoaperiodicmotionastheamplitudeofthesinusoidalflowincreases.