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ASTM G172-2003(2010) 加速运行的寿命数据的统计分析指南

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【英文标准名称】:StandardGuideforStatisticalAnalysisofAcceleratedServiceLifeData
【原文标准名称】:加速运行的寿命数据的统计分析指南
【标准号】:ASTMG172-2003(2010)
【标准状态】:现行
【国别】:美国
【发布日期】:2003
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:G03.08
【标准类型】:(Guide)
【标准水平】:()
【中文主题词】:
【英文主题词】:Acceleratedservicelifedata;Statisticalmethods
【摘要】:Thenatureofacceleratedservicelifeestimationnormallyrequiresthatstresseshigherthanthoseexperiencedduringserviceconditionsareappliedtothematerialbeingevaluated.Fornon-constantusestress,suchasexperiencedbytimevaryingweatheroutdoors,itmayinfactbeusefultochooseanacceleratedstressfixedatalevelslightlylowerthan(say90%of)themaximumexperiencedoutdoors.Bycontrollingallvariablesotherthantheoneusedforacceleratingdegradation,onemaymodeltheexpectedeffectofthatvariableatnormal,orusageconditions.Iflaboratoryacceleratedtestdevicesareused,itisessentialtoprovideprecisecontrolofthevariablesusedinordertoobtainusefulinformationforservicelifeprediction.Itisassumedthatthesamefailuremechanismoperatingatthehigherstressisalsothelifedeterminingmechanismattheusagestress.Itmustbenotedthatthevalidityofthisassumptioniscrucialtothevalidityofthefinalestimate.Acceleratedservicelifetestdataoftenshowdifferentdistributionshapesthanmanyothertypesofdata.Thisisduetotheeffectsofmeasurementerror(typicallynormallydistributed),combinedwiththoseuniqueeffectswhichskewservicelifedatatowardsearlyfailuretime(infantmortalityfailures)orlatefailuretimes(agingorwear-outfailures).Applicationsoftheprinciplesinthisguidecanbehelpfulinallowinginvestigatorstointerpretsuchdata.Thechoiceanduseofaparticularaccelerationmodelandlifedistributionmodelshouldbebasedprimarilyonhowwellitfitsthedataandwhetheritleadstoreasonableprojectionswhenextrapolatingbeyondtherangeofdata.Furtherjustificationforselectingmodelsshouldbebasedontheoreticalconsiderations.Note28212;Acceleratedservicelifeorreliabilitydataanalysispackagesarebecomingmorereadilyavailableincommoncomputersoftwarepackages.Thismakesdatareductionandanalysesmoredirectlyaccessibletoagrowingnumberofinvestigators.Thisisnotnecessarilyagoodthingastheabilitytoperformthemathematicalcalculation,withoutthefundamentalunderstandingofthemechanicsmayproducesomeseriouserrors.SeeRef(1).1.1Thisguidebrieflypresentssomegenerallyacceptedmethodsofstatisticalanalysesthatareusefulintheinterpretationofacceleratedservicelifedata.Itisintendedtoproduceacommonterminologyaswellasdevelopingacommonmethodologyandquantitativeexpressionsrelatingtoservicelifeestimation.1.2ThisguidecoverstheapplicationoftheArrheniusequationtoservicelifedata.Itservesasageneralmodelfordeterminingratesatusageconditions,suchastemperature.Itservesasageneralguidefordeterminingservicelifedistributionatusagecondition.Italsocoversapplicationswheremorethanonevariableactsimultaneouslytoaffecttheservicelife.Forthepurposesofthisguide,theaccelerationmodelusedformultiplestressvariablesistheEyringModel.Thismodelwasderivedfromthefundamentallawsofthermodynamicsandhasbeenshowntobeusefulformodelingsometwovariableacceleratedservicelifedata.Itcanbeextendedtomorethantwovariables.1.3Onlythosestatisticalmethodsthathavefoundwideacceptanceinservicelifedataanalyseshavebeenconsideredinthisguide.1.4TheWeibulllifedistributionisemphasizedinthisguideandexamplecalculationsofsituationscommonlyencounteredinanalysisofservicelifedataarecoveredindetail.ItistheintentionofthisguidethatitbeusedinconjunctionwithGuideG166.1.5Theaccuracyofthemodelbecomesmorecriticalasthenumberofv......
【中国标准分类号】:A41
【国际标准分类号】:03_120_30
【页数】:12P.;A4
【正文语种】:英语


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【英文标准名称】:Broadcastvideotaperecorders-Methodsofmeasurement-Part4:Analogueaudioperformancemeasurements
【原文标准名称】:广播磁带录像机测量方法第4部分:模拟音频性能测量
【标准号】:IEC61237-4-1997
【标准状态】:现行
【国别】:国际
【发布日期】:1997-10
【实施或试行日期】:
【发布单位】:国际电工委员会(IX-IEC)
【起草单位】:IEC/TC100
【标准类型】:()
【标准水平】:()
【中文主题词】:电气工程;音频信号;广播工程;测量;测量技术;视频记录;模拟信号;磁带录像机;电学测量;视频信号
【英文主题词】:Analoguesignals;Audiosignals;Broadcastengineering;Broadcasting;Compatibility;Electricalengineering;Electricalmeasurement;Electroacoustics;Measurement;Measuringtechniques;Recordingequipment;Signals;Testing;Videorecording;Videosignals;Videotaperecorders
【摘要】:ThispartofIEC61237describesmethodsofmeasurementandspecialtestsignalsfortheanalogueaudiopartofequipmentmainlydedicatedtorecordingreproductionofTVsignalsonmagnetictapeonreelsorincassettes.Theallowabletolerancesfortheratedvaluesforacceptableperformancearenotgiveninthisstandard,butmaybederivedfromthespecificationsfortherelatedsystemi.e.appropriatepublications,manufacturers'specifications,etc.ThenecessaryreferenceandcalibrationtapesareeithermentionedinthespecificIECpublicationoftheequipmentundertestorincludedinIEC61105andIEC61295,respectively.Themethodsareapplicabletoacceptancetests,performancecomparisonand,asfaraspossible,toroutinechecks.Toensurethattheresultsobtainedataspecifictimeandataspecificplacearecomparabletoothermeasurements,itisadvisabletospecifythetestsignal,measuringdevicesandtypesoftapesusedtogetherwithresultsobtained.
【中国标准分类号】:M71
【国际标准分类号】:33_160_40
【页数】:47P.;A4
【正文语种】:英语


MIL-STD-2219A (w/CHANGE NOTICE 1), DEPARTMENT OF DEFENSE STANDARD PRACTICE: FUSION WELDING FOR AEROSPACE APPLICATIONS (16 JUN 2008) [S/S BY AWS-D17.1]., The scope of this document is to provide minimum requirements for weld filler materials, workmanship, inspection and record requirements for fusion welding of alloys applicable to aircraft, missiles, other aerospace equipment, their parts and accessories.