【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


【英文标准名称】:Slottedraisedcountersunk(oval)headtappingscrews(commonheadstyle).
【原文标准名称】:带槽半沉头(椭圆形头)自攻螺钉(普通头型)
【标准号】:NFE25-661-1994
【标准状态】:作废
【国别】:法国
【发布日期】:1994-09-01
【实施或试行日期】:1994-09-20
【发布单位】:法国标准化协会(FR-AFNOR)
【起草单位】:
【标准类型】:()
【标准水平】:()
【中文主题词】:
【英文主题词】:Acceptancespecification;Commonheads;Countersunkfasteners;Countersunkheadscrews;Deliveryconditions;Designations;Dimensions;External-threadfasteners;Fasteners;Materials;Raised-headfasteners;Recessedcountersunkheadscrews;Screws(bolts);Self-tappingscrews;Slottedscrews;Slotted-headfasteners;Steels;Threads;Tolerances(measurement)
【摘要】:
【中国标准分类号】:J13
【国际标准分类号】:21_060_10
【页数】:8P.;A4
【正文语种】:其他