简介：

简介：Amodelbasedonthedatafromforcedvibrationexperimentsisdevelopedforpredictingthevortex-inducedvibrations(VIV)ofelasticallymountedcircularcylindersinflow.Theassumptionsforfreeandforcedvibrationtestsareexploredbriefly.Energyequilibriumistakenintoaccounttosetuptherelationshipbetweenthedynamicresponseofself-excitedoscillationsandtheforcecoefficientsfromforcedvibrationexperiments.Thegapbetweenthesetwocasesisbridgedstraightforwardlywithcarefultreatmentofkeyparameters.Givenreducedmassmandmaterialdampingratioζofanelasticallymountedcircularcylinderinflow,theresponsecharacteristicssuchasamplitude,frequency,lock-inrange,addedmasscoefficient,cross-flowfluidforceandthecorrespondingphaseanglecanbepredictedallatonce.InstanceswithdifferentcombinationofreducedmassandmaterialdampingratioarecomparedtoinvestigatetheireffectsonVIV.Thehysteresisphenomenoncanbeinterpretedreasonably.ThepredictionsandtheresultsfromrecentexperimentscarriedoutbyWilliamson'sgroupareinrathergoodagreement.

简介：SubscriptionsEarthquakeEngineeringandEngineeringVibration(PrintISSN1671-3664,CN23-1496/Pwww.iem.net.cn/eeev)ispublishedbiannuallybytheChinaSciencePress.SubscriptionRatesVolume2,2005,2issues?80.00forinstitutionsand?60.00forindividualsformainlandofChina;andUS$80.00andUS$60.00(includingairmailpostage)forinsti-tutionsandindividuals,respectivelyforotherregions.

简介：

简介：Journalwebsite:http://www.springerlink.comAIMSANDSCOPEThisjournalisestablishedbytheInstituteofEngineeringMechanics(IEM),ChinaEarthquakeAdministration,topromotescientificexchangebetweenChineseandforeignscientistsandengineerssoastoimprovethetheoryandpracticeofearthquakehazardsmitigation,preparedness,andrecovery.Toaccomplishthispurpose,thejournalaimstoattractabalancednumberofpapersbetweenChineseand

简介：CopyrightSubmissionofamanuscriptimplies:thattheworkdescribedhasnotbeenpublishedbefore(exceptintheformofanabstract

简介：Submissionofamanuscriptimplies:thattheworkdescribedhasnotbeenpublishedbefore(exceptintheformofanabstractoraspartofapublishedlecture,review,orthesis);thatitisnotunderconsideration

简介：

简介：CopyrightSubmissionofamanuscriptimplies:thattheworkdescribedhasnotbeenpublishedbefore

简介：

简介：Theresonancesofparametricvibrationwithforcedvibrationisanalyzed,thebifurca-tionequationofthesystemisobtainedandthesinsularityanalysisismade.Someofthelawsandphe-nomenaarerevealed.Thetransitionvarietyandbifurcationdiagramofthephysicalparametricplanearegiven.Theresultscanbeusedinensinecrins.

简介：

简介：

简介：Speckleinterferometryisanefficientmethodtoanalyzeavibration.Incetrainconditions,thistechniquehassomeoutsandingadvantage,andneednotstrictshock-proofcondition,comparedwiththeholographicmethodformeasuringvibration,Therefors,itissuitabletoanayyzeavibrationwithalogaramplitude.Real-timeinterferometryisarapidandsimplemethodformeasuringvibrationofabody,givesspecklepatterncontainingamplitudedistributionofbody-surface.Bymeansoftime-averagedmethod.thespecklepatternisrecordedinFouriertransformplane.orvibra-tionlinesareseendirectlywitheyes,soastoanalyzeefficientlyampitude.phase,andmod-elofavibration.Thispaperdeducestheintensitydistributionfunctionwithreal-timemethod,andgivesexpermentaldemonstrationofvibrationbody-thevibrationlineswithdifferentfrequencies.

简介：

简介：

简介：Intheexperimentwehavemeasuredtheresonantfrequenciesofper-foratedsheetswithperforationratesfrom0.008to0.30.Comparedthosefre-quencieswiththecorrespondingresonantfrequenciesofhomogeneous,orun-perforatedoneweobtainedanempiricalrelationshipbetweentheresonantfrequencyandperforationrate,whichcanbeusedforindustrialpurpose.Wehavealsostudiedthechangeofvibrationalenergydistributionofperforatedsheetrelatedtothatofhomogeneous.

简介：我们在某些合理假设下面考虑有弹性的薄盘子的颤动。我们由哈密尔顿原则为这个模型导出非线性的方程。在为起始的数据的hyperbolicity上的条件下面，我们建立本地时间well-posedness为起始并且由Picard重复的边界值问题为解决方案策划，并且获得估计。

简介：Withtheadvantagesoftransmittingenergyfrommultipledirectionstoonedirectionandtransformingvibrationfromonesourcetomultipledirections,thetwo-dimensionalvibrationdirectionconverterhasimportantapplicationsinpowerultrasonictechnology.However,forthecomplexityofusingthewaveequationtodesignandanalysisthetwo-dimensionalvibrationdirectionconverter,aconciseequivalentcircuitfortheconverterisinvestigated.Byintroducingthetwo-dimensionalmechanicalcouplingcoefficientandthelongitudinalforcetransformcoef-ficient,andusingtheelectromechanicalanalogyprinciple,theequivalentcircuitandresonancefrequencyequationofthetwo-dimensionalvibrationdirectionconvertervibratinginanti-phaseandin-phasetwo-dimensionalcoupledvibrationarededuced.Theresonancefrequenciesofthevibrationdirectionconvertersoftwodifferentmaterialsarecalculatedbyusingtheproposedfrequencyequation,whichareinagreementwiththeresultsfromthefiniteelementmethodandtheexperimentaltest.Itprovidesaconcisemethodforthedesignandapplicationsofsuchultrasonicvibrationsystem.

简介：