简介：DynamicbehaviorofsinglepileembeddedintransverselyisotropiclayeredmediaisinvestigatedusingthefiniteelementmethodcombinedwithdynamicstiffnessmatricesofthesoilderivedfromGreen’sfunctionforringloads.Theinfluenceofsoilanisotropyonthedynamicbehaviorofpilesisexaminedthroughaseriesofparametricstudies.

简介：Aneffectivemethodisdevelopedandusedtoinvestigatethean-tiplaneproblemofarigidlineinaconfocalellipticinhomogeneityembeddedinaninfinitemedium.Theanalyticalsolutionisobtained.Theproposedmethodisbasedupontheuseofconformalmappingandthetheoremofanalyticcontinuation.Specialsolutionswhichareverifiedbycomparisonwithexistingonesareprovided.Finally,thecharacteristicsofstresssingularityatthetipoftherigidlineinhomogeneityareanalyzedandtheextensionforcesforthecrackandtherigidlineinhomogeneityarederived.

简介：Ananalyticalmodelisdevelopedtostudythesurfaceeffectsonthevibrationbehaviorincludingthenaturalfrequencyandthecriticalflowvelocityoffluid-conveyingnanotubesembeddedinanelasticmedium.TheeffectsofsurfaceelasticityandresidualsurfacestressareaccountedthroughthesurfaceelasticitymodelandtheYoung-Laplaceequation.AWinkler-typefoundationisemployedtomodeltheinteractionofnanotubesandthesurroundingmedium.Theresultsshowthatthesurfaceeffectshavemoreprominentinfluencesonthenaturefrequencywithsmallernanotubethickness,largeraspectratioandlargerelasticmediumconstants.Bothsurfacelayersandtheelasticmediumenhancethestabilityofnanotubes.Thisstudymightbehelpfulfordesigningthefluid-conveyingnanotubedevicesinNEMSandMEMSsystems.

简介：Thispaperdealswiththefreevibrationanalysisofcircularalumina(Al2O3)nanobeamsinthepresenceofsurfaceandthermaleffectsrestingonaPasternakfoundation.ThesystemofmotionequationsisderivedusingHamilton'sprincipleundertheassumptionsoftheclassicalTimoshenkobeamtheory.Theeffectsofthetransversesheardeformationandrotaryinertiaarealsoconsideredwithintheframeworkofthementionedtheory.Theseparationofvariablesapproachisemployedtodiscretizethegoverningequationswhicharethensolvedbyananalyticalmethodtoobtainthenaturalfrequenciesofthealuminananobeams.TheresultsshowthatthesurfaceeffectsleadtoanincreaseinthenaturalfrequencyofnanobeamsascomparedwiththeclassicalTimoshenkobeammodel.Inaddition,fornanobeamswithlargediameters,thesurfaceeffectsmayincreasethenaturalfrequenciesbyincreasingthethermaleffects.Moreover,withregardtothePasternakelasticfoundation,thenaturalfrequenciesareincreasedslightly.Theresultsofthepresentmodelarecomparedwiththeliterature,showingthatthepresentmodelcancapturecorrectlythesurfaceeffectsinthermalvibrationofnanobeams.

简介：Anumericalstudyofanon-Darcymixedconvectiveheatandmasstransferflowoveraverticalsurfaceembeddedinaporousmediumundertheefectsofdoubledispersion,melting,andthermalradiationisinvestigated.Thesetofgoverningboundarylayerequationsandtheboundaryconditionsistransformedintoasetofcouplednonlinearordinarydiferentialequationswiththerelevantboundaryconditions.ThetransformedequationsaresolvednumericallybyusingtheChebyshevpseudospectralmethod.Comparisonsofthepresentresultswiththeexistingresultsintheliteraturearemade,andgoodagreementisfound.Numericalresultsforthevelocity,temperature,concentrationprofiles,andlocalNusseltandSherwoodnumbersarediscussedforvariousvaluesofphysicalparameters.

简介：Theinfluenceofinitialstrainstateonthedynamicresponseofanendbearingpileembeddedinisotropicsaturatedsoilisinvestigatedthroughthelinearizedtheoryofsmallelasticperturbationsuperposedonlargelystressedbodies.Thegoverningequationsforsoil,basedonBiot’sporoelasticitytheory,arederivedinthecylindricalcoordinates,andthepileismodeledbyusingtheone-dimensionalelastictheory.Theanalyticalsolutionsofpileimpedance,frequencyresponseofbothtwistangleandtimehistoryofvelocityresponseareobtainedbyusingofseparationofvariablestechnique.Finally,aparametricstudyoftheinfluenceofinitialstrainsonthetorsionalimpedance,twistangle,andvelocityresponseatthetopofthepileiscarriedout.