简介：Anewmeshfreemethodproposedbytheauthorswaspresented,inwhichthederivativesateachnodewereconstructedusingwholederivativeformulasthroughthenodesselectedaroundthenodeusinglocalCartesianframeinanautonomousmanner,sothatwithoutanyelementitcouldbeconsideredasacompletelymeshfreemethod.Themethodwastestedwithanumericalexample,andreliablesolutionwasobtainedwithhighaccuracyandefficiency.

简介：ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｐｒｏｂｌｅｍｓｗｉｔｈｌａｒｇｅｇｒａｄｉｅｎｔａｒｅｃｏｍｍｏｎｉｎｐｒａｃｔｉｃａｌｅｎｇｉｎｅｅｒｉｎｇｆｉｅｌｄｓ，ｅ．ｇ．ｉｎｍａｔｅｒｉａｌｌｏｃａｌｉｚａｔｉｏｎ，ｗｉｔｈｉｎｔｈｅｌｏｃａｌｉｚａｔｉｏ...

简介：Efficientoptimizationstrategyofmultibodysystemsisdevelopedinthispaper.AugmentedLagrangemethodisusedtotransformconstrainedoptimalproblemintounconstrainedformfirstly.Thenmethodsbasedonsecondordersensitivityareusedtosolvetheunconstrainedproblem,wherethesensitivityissolvedbyhybridmethod.Generalized-αmethodandgeneralized-αprojectionmethodforthedifferential-algebraicequation,whichshowsmoreefficientpropertieswiththelagertimestep,arepresentedtogetstatevariablesandadjointvariablesduringtheoptimizationprocedure.Numericalresultsvalidatetheaccuracyandefficiencyofthemethodsispresented.

简介：Inthispaper,anewmethodoftopologicalcleanupforquadrilateralmeshispresented.Themethodfirstselectsapatchofmesharoundanirregularnode.Itthenseeksthebestconnectionoftheselectedpatchaccordingtoitsirregularvalenceusinganewtopologicaloperation:smallpolygonreconnection(SPR).Byreplacingtheoriginalpatchwithanoptimalonethathaslessirregularvalence,meshqualitycanbeimproved.Threeapplicationsbasedontheproposedapproachareenumerated:(1)improvingthequalityofaquadrilateralmesh,(2)convertingatriangularmeshtoaquadrilateralone,and(3)adaptingatrianglegeneratortoaquadrilateralone.Thepresentedmethodishighlyeffectiveinallthreeapplications.

简介：Stochasticdynamicanalysisofthenonlinearsystemisanopenresearchquestionwhichhasdrawnmanyscholars'attentionforitsimportanceandchallenge.Fokker–Planck–Kolmogorov(FPK)equationisofgreatsignificancebecauseofitstheoreticalstrictnessandcomputationalaccuracy.However,practicaldifficultieswiththeFPKmethodappearwhentheanalysisofmulti-degree-offreedom(MDOF)withmoregeneralnonlinearityisrequired.Inthepresentpaper,byinvokingtheideaofequivalenceofprobabilityflux,thegeneralhigh-dimensionalFPKequationrelatedtoMDOFsystemisreducedtoone-dimensionalFPKequation.Thenacellrenormalizedmethod(CRM)whichisbasedonthenumericalreconstructionofthederivedmomentsofFPKequationisintroducedbycoarseningthecontinuousstatespaceintoadiscretizedregionofcells.ThenthecellrenormalizedFPK(CR-FPK)equationissolvedbydifferencemethod.Threenumericalexamplesareillustratedandtheeffectivenessofproposedmethodisassessedandverified.

简介：TheproblemofcheckingrobustD-stabilityofmulti-inandmulti-out(MIMO)systemswasstudied.Threesystemmodelswereintroduced,i.e.multilinearpolynomialmatrix,polytopicpolynomialmatrixandfeedbacksystemmodel.Furthermore,theconvexpropertyofeachmodelwithrespecttotheparametricuncertaintieswasestablishedrespectively.Basedonthis,sufficientconditionsforD-stabilitywereexpressedintermsoflinearmatrixinequalities(LMIs)involvingonlytheconvexvertices.Therefore,therobustD-stabilitywastestedbysolvinganLMIoptimalproblem.

简介：Thespinningsolarsailoflargescalehasbeenwelldevelopedinrecentyears.Suchasolarsailcanbeconsideredasarigid-flexiblemultibodysystemmainlycomposedofaspinningcentralrigidhub,anumberofflexiblethintethers,sailmembranes,andtipmasses.Asimplifiedinterplanetarykite-craftacceleratedbyradiationoftheSun(IKAROS)modelisestablishedinthisstudybyusingtheabsolute-coordinate-based(ACB)methodthatcombinesthenaturalcoordinateformulation(NCF)describingthecentralrigidhubandtheabsolutenodalcoordinateformulation(ANCF)describingflexibleparts.Theinitialconfigurationofthesysteminthesecond-stagedeploymentisdeterminedthroughbothdynamicandstaticanalyses.Thehugesetofstiffequationsofsystemdynamicsissolvedbyusingthegeneralized-alphamethod,andthusthedeploymentdynamicsofthesystemcanbewellunderstood.

简介：

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

简介：Apolymericgelisanaggregateofpolymersandsolventmolecules,whichcanretainitsshapeafteralargedeformation.ThedeformationbehaviorofpolymericgelswasoftendescribedbasedontheFlory-Rehnerfreeenergyfunctionwithoutconsideringtheinfluenceofchainentanglementsonthemechanicalbehaviorofgels.Inthispaper,anewhybridfreeenergyfunctionforgelsisformulatedbycombiningtheEdwards-Vilgisslip-linkmodelandtheFlory-Hugginsmixingmodeltoquantifythetime-dependentconcurrentprocessoflargedeformationandmasstransport.Thefiniteelementmethodisdevelopedtoanalyzeexamplesofswelling-induceddeformation.Simulationresultsarecomparedwithavailableexperimentaldataandshowgoodagreement.Theinfluenceofentanglementsonthetime-dependentdeformationbehaviorofgelsisalsodemonstrated.Thestudyoflargedeformationkineticsofpolymericgelisusefulfordiverseapplications.

简介：Althoughthestructuredlightsystemthatusesdigitalfringeprojectionhasbeenwidelyimplementedinthree-dimensionalsurfaceprofilemeasurement,themeasurementsystemissusceptibletonon-linearerror.Inthiswork,weproposeaconvenientlook-up-table-based(LUT-based)methodtocompensateforthenon-linearerrorincapturedfringepatterns.Withoutextracalibration,thisLUT-basedmethodcompletelyutilizesthecapturedfringepatternbyrecordingthefull-fielddifferences.Then,aphasecompensationmapisestablishedtorevisethemeasuredphase.Experimentalresultsdemonstratethatthismethodworkseffectively.

简介：

简介：Uncertaintyisinherentandunavoidableinalmostallengineeringsystems.Itisofessentialsignificancetodealwithuncertaintiesbymeansofreliabilityapproachandtoachieveareasonablebalancebetweenreliabilityagainstuncertaintiesandsystemperformanceinthecontroldesignofuncertainsystems.Nevertheless,reliabilitymethodswhichcanbeuseddirectlyforanalysisandsynthesisofactivecontrolofstructuresinthepresenceofuncertaintiesremaintobedeveloped,especiallyinnon-probabilisticuncertaintysituations.Inthepresentpaper,theissueofvibrationcontrolofuncertainstructuresusinglinearquadraticregulator(LQR)approachisstudiedfromtheviewpointofreliability.Ane?cientnon-probabilisticrobustreliabilitymethodforLQR-basedstaticoutputfeedbackrobustcontrolofuncertainstructuresispresentedbytreatingboundeduncertainparametersasintervalvariables.Theoptimalvibrationcontrollerdesignforuncertainstructuresiscarriedoutbysolvingarobustreliability-basedoptimizationproblemwiththeobjectivetominimizethequadraticperformanceindex.Thecontrollerobtainedmaypossessoptimumperformanceundertheconditionthatthecontrolledstructureisrobustlyreliablewithrespecttoadmissibleuncertainties.Theproposedmethodprovidesanessentialbasisforachievingabalancebetweenrobustnessandperformanceincontrollerdesignofuncertainstructures.Thepresentedformulationsareintheframeworkoflinearmatrixinequalityandcanbecarriedoutconveniently.Twonumericalexamplesareprovidedtoillustratethee?ectivenessandfeasibilityofthepresentmethod.

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

简介：Differentfrombirdsandinsects,batshavecomplexwing-deformationcapacitytogeneratehighaerodynamicforces.Inflight,theactivelymorphingofbatwingincludesthetwistingfromwingroottowingtip,thecamberingalongthechordwisedirection,thebendingalongthespanwisedirectionandthewingarea-changingcausedbythestretchandretractionofthewingspan.Itwasfoundthatthehighthrustandliftrequiredinbatflightaredependentonthewingtwistingandcamberingrespectively.Moreover,theintegratedwing-morphinggeneratestheaerodynamicliftandthrustmainlyduringthedownstrokeandalmostnegligibleforcesduringtheupstroke.Thewingarea-changingandbendingcanbeusedtoamplifythepositiveforcesinthedownstrokedurationandreducethenegativeforcesintheupstrokeduration.

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

简介：

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。

简介：ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｏｕｇｈｓｉｎｇｕｌａｒＢｏｕｎｄａｒｙｅｌｅｍｅｎｔｉｓｒｅｇａｒｄｅｄａｓａｋｉｎｄｏｆｗｅｉｇｈｔｅｄｒｅｓｉｄｕａｌｓ，ｔｈｅｓｉｎｇｕｌａｒｂｏｕｎｄａｒｙｅｌｅｍｅｎｔｈａｓａｕｎｉｑｕｅｃｈａｒａｃｔｅｒｉｓ...