简介：Anumericalstudybasedonawakeoscillatormodelwasconductedtodeterminetheresponseperformanceofvortex-inducedvibration(VIV)onalongflexiblecylinderwithpinned-pinnedboundaryconditionssubjectedtolinearandexponentialshearflows.Thecouplingequationsofastructuralvibrationmodelandwakeoscillatormodelweresolvedusingastandardcentralfinitedifferencemethodofthesecondorder.TheVIVresponsecharacteristicsincludingthestructuraldisplacement,structuralfrequency,structuralwavenumber,standingwavebehavior,travellingwavebehavior,structuralvelocity,liftforcecoefficientandtransferredenergyfromthefluidtothestructurewithdifferentflowprofileswerecompared.ThenumericalresultsshowthattheVIVdisplacementisacombinationofstandingwavesandtravellingwaves.Forlinearshearflow,standingwavesandtravellingwavesdominatetheVIVresponsewithinthelow-velocityandhigh-velocityzones,respectively.Thenegativevaluesofthetransferredenergyonlyoccurwithinthelow-velocityzone.However,forexponentialshearflow,travellingwavesdominatetheVIVresponseandthenegativeenergyoccursalongtheentirelengthofthecylinder.

简介：Multipleregenerationofaxonalbudshasbeenshowntoexistduringtherepairofperipheralnerveinjury,whichconfirmsacertainrepairpotentialoftheinjuredperipheralnerve.Therefore,asystematicnervetranspositionrepairtechniquehasbeenproposedtotreatsevereperipheralnerveinjury.Duringnervetranspositionrepair,theregeneratednervefibersofmotorneuronsintheanteriorhornofthespinalcordcaneffectivelygrowintotherepaireddistalnerveandtargetmuscletissues,whichisconducivetotherecoveryofmotorfunction.Theaimofthisstudywastoexploreregenerationandnervefunctionalrecoveryafterrepairingalong-segmentperipheralnervedefectbytranspositionofdifferentdonornerves.Along-segment(2mm)ulnarnervedefectinSprague-Dawleyratswasrepairedbytranspositionofthemusculocutaneousnerve,medialpectoralnerve,muscularbranchesoftheradialnerveandanteriorinterosseousnerve(pronatorquadratusmusclebranch).Insiturepairoftheulnarnervewasconsideredasacontrol.Threemonthslater,wristflexionfunction,nerveregenerationandinnervationmusclerecoveryinratswereassessedusingneuroelectrophysiologicaltesting,osmicacidstainingandhematoxylin-eosinstaining,respectively.Ourfindingsindicatethatrepairofalong-segmentulnarnervedefectwithdifferentdonornervetranspositionscanreinnervateaxonalfunctionofmotorneuronsintheanteriorhornofspinalcordandrestorethefunctionofaffectedlimbstoacertainextent.

简介：Cable-membranestructureshavesmallrigidityandarehighlysensitivetowind.Structuralhealthmonitoringisnecessarytoensuretheserviceabilityandsafetyofthestructure.Inthisresearch,thedesignmethodofastructuralhealthmonitoringsystemisusingthecharacteristicsofacable-membranestructure.TakingtheYueyangSanheAirportTerminalasanexample,afiniteelementmodelisestablishedtodeterminethecriticalstructuralcomponents.Next,theengineeringrequirementsandtheframeworkofthemonitoringsystemarestudiedbasedontheresultsofnumericalanalysis.Thespecificimplementationofthestructuralhealthmonitoringisthencarriedout,whichincludessensorselection,installationandwiring.TheproposedframeworkissuccessfullyappliedtothemonitoringsystemfortheYueyangAirportterminalbuilding,andthesynchronousacquisitionoffiberBragggratingandaccelerationsensorsignalsisimplementedinaninnovativeway.Thesuccessfulimplementationandoperationofstructuralhealthmonitoringwillhelptoguaranteethesafetyofthecablemembranestructureduringitsservicelife.