ASME中国制造-ASTM-E29-2013-(原文)

Designation:E29−13AnAmericanNationalStandardStandardPracticeforUsingSignificantDigitsinTestDatatoDetermineConformancewithSpecifications1ThisstandardisissuedunderthefixeddesignationE29;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheDepartmentofDefense.1.Scope*1.1Thispracticeisintendedtoassistthevarioustechnicalcommitteesintheuseofuniformmethodsofindicatingthenumberofdigitswhicharetobeconsideredsignificantinspecificationlimits,forexample,specifiedmaximumvaluesandspecifiedminimumvalues.Itsaimistooutlinemethodswhichshouldaidinclarifyingtheintendedmeaningofspecificationlimitswithwhichobservedvaluesorcalculatedtestresultsarecomparedindeterminingconformancewithspecifications.1.2ThispracticeisintendedtobeusedindeterminingconformancewithspecificationswhentheapplicableASTMspecificationsorstandardsmakedirectreferencetothisprac-tice.1.3Referencetothispracticeisvalidonlywhenachoiceofmethodhasbeenindicated,thatis,eitherabsolutemethodorroundingmethod.1.4Thesystemofunitsforthispracticeisnotspeci-fied.Dimensionalquantitiesinthepracticearepresentedonlyasillustrationsofcalculationmethods.Theexamplesarenotbindingonproductsortestmethodstreated.1.5Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2E177PracticeforUseoftheTermsPrecisionandBiasinASTMTestMethodsE456TerminologyRelatingtoQualityandStatisticsE2282GuideforDefiningtheTestResultofaTestMethodIEEE/ASTMSI10StandardforUseoftheInternationalSystemofUnits(SI):TheModernMetricSystem3.Terminology3.1Definitions—TerminologyE456providesamoreexten-sivelistoftermsinE11standards.3.1.1observedvalue,n—thevalueobtainedbymakinganobservation.E22823.1.2repeatabilityconditions,n—conditionswhereinde-pendenttestresultsareobtainedwiththesamemethodonidenticaltestitemsinthesamelaboratorybythesameoperatorusingthesameequipmentwithinshortintervalsoftime.E1773.1.3repeatabilitystandarddeviation(sr),n—thestandarddeviationoftestresultsobtainedunderrepeatabilityconditions.E1773.1.4significantdigit—anyofthefigures0through9thatisusedwithitsplacevaluetodenoteanumericalquantitytosomedesiredapproximation,exceptingallleadingzerosandsometrailingzerosinnumbersnotrepresentedwithadecimalpoint.3.1.4.1Discussion—Thisdefinitionofsignificantdigitsre-latestohowthenumberisrepresentedasadecimal.Itshouldnotbeinferredthatameasurementvalueisprecisetothenumberofsignificantdigitsusedtorepresentit.3.1.4.2Discussion—Thedigitzeromayeitherindicateaspecificvalueorindicateplaceonly.Zerosleadingthefirstnonzerodigitofanumberindicateorderofmagnitudeonlyandarenotsignificantdigits.Forexample,thenumber0.0034hastwosignificantdigits.Zerostrailingthelastnonzerodigitfornumbersrepresentedwithadecimalpointaresignificantdigits.Forexample,thenumbers1270.and32.00eachhavefoursignificantdigits.Thesignificanceoftrailingzerosfornumbersrepresentedwithoutuseofadecimalpointcanonlybeidentifiedfromknowledgeofthesourceofthevalue.Forexample,amodulusstrength,statedas140000Pa,mayhaveasfewastwoorasmanyassixsignificantdigits.1ThispracticeisunderthejurisdictionofASTMCommitteeE11onQualityandStatisticsandisthedirectresponsibilityofSubcommitteeE11.30onStatisticalQualityControl.CurrenteditionapprovedAug.1,2013.PublishedAugust2013.Originallyapprovedin1940.Lastpreviouseditionapprovedin2008asE29–08.DOI:10.1520/E0029-13.2ForreferencedASTMstandards,visittheASTMwebsite,@astm.org.ForAnnualBookofASTMStandardsvolumeinformation,refertothestandard’sDocumentSummarypageontheASTMwebsite.*ASummaryofChangessectionappearsattheendofthisstandardCopyright©ASTMInternational,100BarrHarborDrive,POBoxC700,WestConshohocken,PA19428-2959.UnitedStates1CopyrightASTMInternationalProvidedbyIHSunderlicensewithASTMNotforResaleNoreproductionornetworkingpermittedwithoutlicensefromIHS--`,,```,,,,````-`-`,,`,,`,`,,`---3.1.4.3Discussion—Toeliminateambiguity,theexponen-tialnotationmaybeused.Thus,1.40×105indicatesthatthemodulusisreportedtothenearest0.01×105or1000Pa.3.1.4.4Discussion—UseofappropriateSIprefixesisrec-ommendedformetricunitstoreducetheneedfortrailingzerosofuncertainsignificance.Thus,140kPa(withoutthedecimalpoint)indicatesthatthemodulusisreportedeithertothenearest10or1kPa,whichisambiguouswithrespecttothenumberofsignificantdigits.However,0.140MPaclearlyindicatesthatthemodulusisreportedtothenearest1kPa,and0.14MPaclearlyindicatesthatthemodulusisreportedtothenearest10kPa.3.1.5testresult,n—thevalueofacharacteristicobtainedbycarryingoutaspecifiedtestmethod.E22824.SignificanceandUse4.1Thispracticedescribestwocommonlyacceptedmeth-odsofroundingdata,identifiedastheAbsoluteMethodandtheRoundingMethod.Intheapplicationso