学术-型海报模板

INTRODUCTIONReliabilitytestsareusuallyconductedatacertainvirtualenvironmentalstresslevelwhereasthefieldenvironmentishighlyvariedfromthevirtualenvironment.Thispaperpresentsanovelmethodoffieldreliabilitypredictionconsideringenvironmentvariationandproductindividualdispersion.Wienerdiffusionprocesswithdriftwasusedfordegradationmodelingandalinkfunctionwhichpresentsdegradationrateisintroducedtomodeltheimpactofvariedenvironmentandindividualdispersion.Resultsindicatesthatproperlymodeled(properdistributiontypeandparameters)environmentalstressisthefundamentalofvariedenvironmentorientedreliabilityprediction.ResultsDegradationmodellingCaseResultsconsideringdispersionACKNOWLEGEMENTThisworkissupportedbytheNationalNaturalScienceFoundationofChina(GrantNo.xxxxxxxx).xxxxxxHeiscurrentlyaPh.D.candidateattheSchoolofxxxxxx,xxxxxxUniversity.Hisresearchinterestsincludexxxxxx.BIOGRAGHYCONCLUSIONGamma,transformed-Gamma(T-Gamma)andNormaldistributionwithdifferentparametersareemployedtomodelright-skewed,left-skewedandsymmetricstressdistribution.Resultsshowobviousdifferenceinreliability,failureintensityandfailureratebetweenvariedstressandconstantstresssituationandeachother.Itindicatesthatproperlymodeled(properdistributiontypeandparameters)environmentalstressisthefundamentalofvariedenvironmentorientedreliabilityprediction.InalineardriftdegradationprocessandArrhenius-typelinkfunctionsituation,itisreasonablenotconcerningaboutproductindividualdispersionbecausetheimpactisbarelysmall,whileothersituationscanbestudiedinthesamewayproposedinthispresentpaper.Thereliabilitycurvecalculatedbythemethodpresentedinthispaperisratherdifferentfromtheresultsbytakingtheaverageofenvironmentalfactorsanddifferentparametersforthesamedistributionhaveobviousimpactonreliability.Undertheconditionofsameaverageandvariance,thecurvesofGamma,T-Gamma,andNormaldistributedtemperatureisdifferenttoo.Fiveunitsweresubjectedtoanaccelerateddegradationtestateachof60°C,85°C,110°Cand140°C.Thedegradationdataforeachunitwasobservedatt1=100,t2=200,t3=300,t4=400,t5=500,t6=600,t7=700,t8=800,t9=900,t10=1000(inhours).Gamma,transformedGammaandNormaldistributionwithdifferentparametersarechosentostudytheinfluenceoftemperatureonreliability.NormalandGammadistributionwithdifferentparametersarechosentostudytheinfluenceofindividualdispersiononreliability.Wienerprocessisawidelyusedmethodindegradationprocessandcanbeseenasadegradationratemodel.ThefirsttimethatthedegradationprocesscrossesthecriticalthresholdvalueDfollowsanInverseGaussiandistribution,andthereliabilityfunctioncanbegivenasAssumeisthedegradationvalueoftheithproductattime,thenandTheeffectthatenvironmentalfactorsandindividualdispersionhaveondegradationprocesscanbeconsideredaschangesinthedegradationratewithalinkfunctionsuchastheArrheniusrelationshipThevariedenvironmentalfactorsandindividualdispersioncanbemodelledbygivingadistributiontotheparameterzanda.Thereliabilityfunctionfollowswhereandaredensityfunctionsforzanda.()iijxt2()()2()()expDtRttDtDttt()()()XtBttijt2()~(,)ijijijijijxBtNt1()ijijijijijxfxttbzzaez|,UULLazazRtRtzafzfadzdafzfaTypeProbabilityDensityParameterAverageVarianceGamma142265674241124721196T-Gamma142305674321124735196Normal287.528562810.528112281428196TypeParameterAverageVarianceNormal(200,15)200225(200,10)200100(200,5)20025Gamma(4,2/15,170)200225(9,3/10,170)200100(36,6/5,170)20025,N,,Underthesamestressdistribution,reliabilitycurvesofdifferentindividualdispersionsituationswiththesameaveragevaluearealmostthesame,showingnosignificantvariance.