简介：Itisveryimportanttomeasurelocaldeformationsforanin-depthunderstandingofmechanicalpropertiesandfracturemechanismofstructuralandfunctionalmaterials.Inthispaper,differenttypesofmodelgridfabricationmethodsandmanytypesofelectronMoiremethodsusinganelectronbeamdrawingsystem,ascanningelectronmicroscopeorafocusionbeamarereported,togetherwiththeirapplicationsinthemeasurementofdeformationsoccurringinvariousengineeringsandmaterialsscienceresearch.

简介：Inthispaper,wepresentthesimplificationofSachsformulasforthemeasurementandcalculationoftheresidualstressesoftheeylinderonlywiththeplanestresses.Furthermore,wepresentthemethodforthemeaurementandcalculationoftheresidualstressesofthecylindernotonlywiththefinitelengthbutwiththelongitudinalstress.Thesecanbeappliedtotheinvestigationontheresidualstressesoftheautofrettedguntube.

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简介：Inthispaper,wecombinethedirect-forcingfictitiousdomain(DF/FD)methodandthesharpinterfacemethodtoresolvetheproblemofparticledielectrophoresisintwodimensions.TheflowfieldandthemotionofparticlesaresolvedwiththeDF/FDmethod,theelectricfieldissolvedwiththesharpinterfacemethod,andtheelectrostaticforceontheparticlesiscomputedusingtheMaxwellstresstensormethod.Theproposedmethodisvalidatedviathreeproblems:effectiveconductivityofparticlecompositebetweentwoplanarplates,celltrappinginachannel,andmotionofparticlesduetobothconventionalandtravelingwavedielectrophoreticforces.

简介：射击peening是由在金属性的材料的表面附近产生压缩剩余应力增加疲劳生活和抵抗到腐蚀疲劳的一个广泛地使用的表面处理方法，裂开，等等。压缩剩余应力和凹部侧面是重要因素评估射击peening过程的有效性。在这份报纸，最大的压缩剩余应力和凹部的最大的深度上的无尺寸的参数的影响被调查。第一，处理影响最大的压缩剩余压力和凹部的最大的深度的参数的无尺寸的关系被维的分析方法推出。第二，无尺寸的变量上的每个无尺寸的参数的影响被有限元素方法调查。而且，相关实验公式基于模拟结果为每个无尺寸的参数被给。最后，比较被做，好同意在模拟结果和实验公式之间被发现，它证明一条有用途径为分析每个单个参数的影响在这份报纸被提供。

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简介：ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｏｕｇｈｓｉｎｇｕｌａｒＢｏｕｎｄａｒｙｅｌｅｍｅｎｔｉｓｒｅｇａｒｄｅｄａｓａｋｉｎｄｏｆｗｅｉｇｈｔｅｄｒｅｓｉｄｕａｌｓ，ｔｈｅｓｉｎｇｕｌａｒｂｏｕｎｄａｒｙｅｌｅｍｅｎｔｈａｓａｕｎｉｑｕｅｃｈａｒａｃｔｅｒｉｓ...

简介：Underinspirationfromthestructure-preservingpropertyofsymplecticdifferenceschemesforHamiltoniansystems,twohomogenizationconditionsforarepresentativeunitcelloftheperiodicalcompositesareproposed,oneconditionistheequivalenceofstrainenergy,andtheotheristhedeformationsimilarity.Basedonthesetwohomogenizationconditions,aneigenelementmethodispresented,whichischaracteristicofstructure-preservingproperty.Itfollowsfromthefrequencycomparisonsthattheeigenelementmethodismoreaccuratethanthestiffnessaveragemethodandthecomplianceaveragemethod.

简介：Anewandefficienttechniquefordeterminingoptimallocationsofsensorsandactuatorsofintelligentstructuresispresented.Theoptimizationofsensorandactuatorlocationsisbasedonthe1stordersingularvalueperturbationsofobservabilityandcontrollability.Usingthismethodtheoptimalplacementsofsensorsandactuatorsoftheintelligentstructurercanbeselected.Twonumericalexamplesaregiventodemonstratetheapplicationsofthemethod.Theimpulseresponsesofstructuresduetodifferentlocationsofactuatorswiththesamecontrollawareanalyzedindetail.

简介：Inthispaper,weproposeageneralizedformofthePLKmethod.Tosolveweaklynonlinearprob-lems,instrainingtherelatedcoordinates,wechooseakindoftransformationsincludingnonlinearfunctionalsofde-pendentvariablestolinearizeasymptoticallytheoriginalproblems,andgivemoreperfectasymptoticsolutionswiththefirst-termapproximationandthederivedtransformations.Theanalysisforsomepracticalexamplesshowsthatthegeneralizedmethodisstraightforwardandeffectiveandmightbeappliedtomorecomplicatednonlinearproblems.

简介：ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｃｏｎｃｅｐｔｓｏｆＩｎｅｒｔｉａｌＭａｎｉｆｏｌｄ（ＩＭ）［１］ａｎｄＡｐｐｒｏｘｉｍａｔｅＩｎｅｒｔｉａｌＭａｎｉｆｏｌｄ（ＡＩＭ）［２］ｆｏｒｄｉｓｓｉｐａｔｉｖｅｐａｒｔｉａｌｄｉｆｆｅｒｅｎｔｉａｌｅｑｕａｔｉ...

简介：Anindependentmethodforpaper[10]ispresented.WeightedlatticepathsareemumeratedbycountingfunctionwhichisanaturalextensionofGaussianmultinomialcoefficientinthecaseofunrestrictedpaths.Convolutionsforpathcountsareinvestigated.whichyieldssomeVandermonde-typeidentitiesformultinomialandq-multinomialcoefficients.

简介：Tobettersimulatemulti-phaseinteractionsinvolvingfailureevolution,thematerialpointmethod(MPM)hasevolvedforalmosttwentyyears.Recently,aparticle-basedmultiscalesimulationprocedureisbeingdeveloped,withintheframeworkoftheMPM,todescribethedetonationprocessofenergeticnano-compositesfrommoleculartocontinuumlevelsothatamultiscaleequationofstatecouldbeformulated.Inthisletter,amultiscaleMPMisproposedviabothhierarchicalandconcurrentschemestosimulatetheimpactresponsebetweentwomicrorodswithdifferentnanostructures.Preliminaryresultsarepresentedtoillustratethatatransitionregionisnotrequiredbetweendifferentspatialscaleswiththeproposedapproach.

简介：Inthispaper,weintroducedtherandommaterials,geometricalshapes,forceanddisplacementboundaryconditiondirectlyintothefunctionalvariationalformulationsanddevelopedaunifiedrandomvariationalprincipleandfiniteelementmethodwiththesmallparameterperturbationmethod.Numericalexamplesshowedthatthemethodshavetheadvantagesofthesimpleandconvenientprogramimplementation,andareeffectivefortherandommechanicsproblems.

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简介：Thenumericalandphysicalissuesofsimulationsoncompressibleturbulencearereviewedinthepresentpaper.Anoutlineoftheglobalspectralmeth-odsandtheprogressofrecentlocalspectralmethodsareillustrated.Severaltypicalsubjectsinthisfieldarestudied,includinghomogeneousisotropicturbulence,au-toignitioninpremixedturbulence,interactionbetweenflamesandturbulence,andshockwaveinturbulence.Theresultsofthenumericalsimulationsarediscussed,enablingustodiscoverandtounderstandthephysicalphenomenawhichhavenotbeensolvedbyexperiments.

简介：Byusingthefundamentalequationsofaxisymmetricshallowshellsofrevolution,thenonlinearbendingofashallowcorrugatedshellwithtaperunderarbitraryloadhasbeeninvestigated.ThenonlinearboundaryvalueproblemofthecorrugatedshellwasreducedtothenonlinearintegralequationsbyusingthemethodofGreen'sfunction.Tosolvetheintegralequations,expansionmethodwasusedtoobtainGreen'sfunction.ThentheintegralequationswerereducedtotheformwithdegeneratecorebyexpandingGreen'sfunctionasseriesofcharacteristicfunction.Therefore,theintegralequationsbecomenonlinearalgebraicequations.Newton'siterativemethodwasutilizedtosolvethenonlinearalgebraicequations.Toguaranteetheconvergenceoftheiterativemethod,deflectionatcenterwastakenascontrolparameter.Correspondingloadswereobtainedbyincreasingdeflectiononebyone.Asanumericalexample,elasticcharacteristicofshallowcorrugatedshellswithsphericaltaperwasstudied.Calculationresultsshowthatcharacteristicofcorrugatedshellschangesremarkably.Thesnappinginstabilitywhichisanalogoustoshallowsphericalshellsoccurswithincreasingloadifthetaperisrelativelylarge.Thesolutionisclosetotheexperimentalresults.

简介：ThefundamentalsolutionsoftheorthotropicthickplatestakingintoaccountthetransversesheardeformationarederivedbymeansofHrmander’soperatormethodandaplane-wavedecompositionoftheDiracδ-functioninthispapey.Theboundaryintegralequationsofthethickplateshavebeenformulatedwhichareadaptedtoarbitraryboundaryconditionsandplaneforms.Thenumericalcalculationofthefundamentalsolutionsisdiscussedindetail.SomenumericalexamplesareanalyzedwithBEM.

简介：Thevibrationmethodrepresentsapracticalmethodforthemeasurementofadhesionforcesandadhesionforcedistributions.Thismethodcausessinusoidallyalternatingstressesandyieldsdetachmentandcontactforcesbetweenparticlesandsubstrateofthesameorderofmagnitude.Alternatingcontactforcesofthevibrationmethodcancauseanadhesionforceintensificationthroughflatteningofasperities.Themeasuringprincipleofthevibrationmethodandtheanalysisofexperimentalresultsaredescribedinthearticle.Normaladhesionforces(pull-offforces)aremeasuredusingthevibrationmethodandthecolloidalprobetechnique.Theresultsofbothmethodsshowgoodagreementforsmallparticlesizes.Theinfluenceofthedetachmentforcedirectionisshownbycomparingtangentialandnormaladhesionforcesmeasuredusingparticlereentrainmentinaturbulentairflowandthevibrationmethod,respectively.Thesurfaceroughnessofthesubstrateandtherelativehumidityareshowntosignificantlyinfluencethemeasuredadhesionforces.Forthecalculationoftheadhesionforces,anapproachbyRabinovichwascombinedwithapproximationsofplasticmicroasperityflattening.TheRabinovichapproachaccountsforroughnesseffectsonthevanderWaalsforcebyincorporatingthermsroughnessoftheinteractingsurfaces,rms-valuesoftheparticlesandsubstratesweremeasuredwithatomicforcemicroscopyatdifferentscanningareas.

简介：WiththeincorporationoftotalLagrangiansmoothedparticlehydrodynamics（SPH）methodequationandmovingleastsquare（MLS）function,thetraditionalSPHmethodisimprovedregardingthestabilityandconsistency.BasedonMindlin-Ressinerplatetheory,theSPHmethodsimulatingdynamicbehaviorviaonelayerofparticlesisappliedtoplate＇smid-plane,i.e.,aSPHshellmodelisconstructed.Finally,throughcomparativeanalysesonthedynamicresponseofsquare,stiffenedshellsandcylindricalshellsundervariousstrongimpactloadswithcommonfiniteelementsoftware,thefeasibility,validityandnumericalaccuracyoftheSPHshellmethodareverified.Consequently,furtherresearchesonSPHshellmaywellpavethewaytowardssolvingproblemsinvolvingdynamicplasticdamage,tearingorevencrushing.