简介:Wereportthefabricationprocessofpiezoelectriccellulosepaperandtheenhancementmethodofitspiezoelectricproperty.Stretchingmethodwithdifferentwet-drawingratioswasintroducedtoincreasethepiezoelectricpropertyofcellulosepaperduringregenerationprocess.ItisobservedthattheYoung’smodulusandthepiezoelectricchargeconstantsareverydependentonthedrawingratioandthedirectionofnanofibrilsofpiezoelectricpaper.Usingtheenhancedpiezoelectricproperty,weprovethattheflexibleregeneratedpiezoelectriccellulosecanbeappliedtothepotentialacousticapplicationssuchasthinpiezoelectricpaperspeaker.
简介:ThepropertiesofFeMnSiCrNishapememoryalloywereinvestigated.TheresultsshowthatthebestshapememoryeffectofFel4Mn6Si9Cr5Nialloyis85%.Thetransformationamountoftheε→γtransformationisnotcompleteafterheatingthealloyto1000K,AsandAfpointsdropwithincreasedtransformationenthalpy(△Hγ→ε)bythermalcyclingandincreasedprestrain.Thealloyshowsalsogoodcreepandstressrelaxationresistance.Inaddition,thealloyhavingatensileforceof20kNandasealingpressureof6MPacansatisfyrequirementsforpossibleindustrialapplicationonpipejoints.
简介:Thispaperdescribesanovelwavelet-basedapproachtothedetectionofabruptfaultofRotorcraftUnmannedAerialVe-hicle(RUAV)sensorsystem.Byuseofwavelettransformsthataccuratelylocalizethecharacteristicsofasignalbothinthetimeandfrequencydomains,theoccurringinstantsofabnormalstatusofasensorintheoutputsignalcanbeidentifiedbythemulti-scalerepresentationofthesignal.Oncetheinstantsaredetected,thedistributiondifferencesofthesignalenergyonalldecomposedwaveletscalesofthesignalbeforeandaftertheinstantsareusedtoclaimandclassifythesensorfaults.
简介:Abiomimetichipjointsimulatorthatcanbeusedtoevaluatetheoutcomeofthecementedtotalhipreplacementhasbeendesigned,manufacturedandevaluated.Thesimulatorproducesmotionintheextension/flexionplane,withasockettorotateinternal/externally.Atthesametimeadynamicloadingcycleisapplied.Avalidationtestwasperformedonacementedfemoralstemwithinanovelcompositefemur.Thebonequalityhasastrongeffectonthestemmigrationandontheintegrityoftheinterfaces.Themigrationofthestemisacombinationof3-Dtranslationandrotationofthestem.Underthesameloadingconditions,weakboneallowsmorestemmigrationthanstrongbone.Thereisagreatdecreaseinthestrengthofthestem-cementinterfaceafterthedynamictest,andtheweakbonecompositeexhibitedagreaterreductionininterfacialstrengththanthestrongbonecomposite.Thedecreaseoftheinterfacialstrengthindicatesthattheprimarybondingbetweenthestemandthecementmantlehaddeterioratedandtheintegrityofstem-cementinterfacewasdamaged.Thestudydemonstratesthevalueofusingahipjointsimulatortoinvestigatestemmigrationandinterfaceintegritywithinthecementedhipreplacement,suggestingthatmethodcanbeusedforinvitroevaluationofthebiomaterialsusedinthecementedhipreplacements.