简介：Insomesituations,theacceleratedlifetestonenvironmentalstressforelectronicproductsisnoteasilyimplementedduetovariousrestrictions,andthusengineersarelackingofdataoftheproductlifetest.Concerningthisproblem,environmentallifeoftheprintedcircuitboard(PCB)boardiscalculatedbywayofphysicsoffailure.InfluencesofthermalcycleandvibrationonPCBanditscomponentsarestudied.BasedontheanalysisofforceandstressbetweencomponentsandthePCBboardinthermalcycleeventsandvibrationevents,fourlifecomputingmodelsofpinsandsoldereddotsareestablished.Themillerdamageratioisusedtocalculatetheaccumulateddamageofapinorasoldereddot,andthentheenvironmentlifeofthePCBboardcanbedeterminedbythefirstfailedone.Finally,anexampleisusedtoillustratethemodelsandtheircalculations.

简介：ThelifeofimpregnatedBa-Wcathodeswithanewconstructionhavebeenevaluatedusinganacceleratedlifetestatthreedifferenttemperatures(1170℃,1130℃,1090℃)andconstantcurrentdensity(2A/cm~2).Accordingtotherelationshipoflifewithoperatingtemperatures,anacceleratedequationhasbeensetup.Thecathodelifeatnormaloperatingtemperatureisdeductedbasedontheacceleratedequation.Theresultsshowthatlifeofthenovelcathodeexceeds190,000houratacurrentdensityof2A/cm~2.

简介：近日，LifeSignals有限公司推出了LifeSignalProduct平台（LSP），提供世界首个针对移动、可穿戴的医疗及健康监护等生命关键应用进行优化设计的半导体芯片产品系列。

简介：UnderType-IIprogressivelyhybridcensoring,thispaperdiscussesstatisticalinferenceandoptimaldesignonstepstresspartiallyacceleratedlifetestforhybridsysteminpresenceofmaskeddata.ItisassumedthatthelifetimeofthecomponentinhybridsystemsfollowsindependentandidenticalmodifiedWeibulldistributions.Themaximumlikelihoodestimations(MLEs)oftheunknownparameters,accelerationfactorandreliabilityindexesarederivedbyusingtheNewton-Raphsonalgorithm.Theasymptoticvariance-covariancematrixandtheapproximateconfidenceintervalsareobtainedbasedonnormalapproximationtotheasymptoticdistributionofMLEsofmodelparameters.Moreover,twobootstrapconfidenceintervalsareconstructedbyusingtheparametricbootstrapmethod.TheoptimaltimeofchangingstresslevelsisdeterminedunderD-optimalityandA-optimalitycriteria.Finally,theMonteCarlosimulationstudyiscarriedouttoillustratetheproposedprocedures.