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【英文标准名称】:StandardSpecificationforElectric-Fusion-WeldedSteelPipeforAtmosphericandLowerTemperatures
【原文标准名称】:常温和较低温用电熔焊钢管的标准规范
【标准号】:ASTMA671-1996
【标准状态】:作废
【国别】:美国
【发布日期】:1996
【实施或试行日期】:
【发布单位】:美国材料与试验协会(ASTM)
【起草单位】:ASTM
【标准类型】:()
【标准水平】:()
【中文主题词】:管道;温度;管;钢;熔焊
【英文主题词】:steels;pipes;temperature;pipelines;fusionwelding
【摘要】:
【中国标准分类号】:H48
【国际标准分类号】:23_040_10
【页数】:7P;A4
【正文语种】:英语


【英文标准名称】:StandardPracticeforClassificationofComputedRadiologySystems
【原文标准名称】:计算机辐射系统分类的标准实施规程
【标准号】:ASTME2446-2005(2010)
【标准状态】:现行
【国别】:美国
【发布日期】:2005
【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】:E07.01
【标准类型】:(Practice)
【标准水平】:()
【中文主题词】:
【英文主题词】:basicspatialresolution.;classification;computedradiology;CR;filmsystemclassification;normalizedSNR;photo-stimulatedluminescence;PSL;Imagequality;Computedradiologysystems;Industrialradiographicfilmprocessing/testing;Phosphor
【摘要】:ThereareseveralfactorsaffectingthequalityofaCRimageincludingthespatialresolutionoftheIPsystem,geometricalunsharpness,scatterandcontrastsensitivity(signal-to-noiseratio),aswellassoftware.Thereareseveraladditionalfactors(forexample,scanningparameters),whichaffecttheaccuratereadingofimagesonexposedIPsusinganopticalscanner.ThispracticeistobeusedtoestablishaclassificationofCRsystemclassesonthebasisofanormalizedSNR.Duetothedifferencebetweenthemethods,itisrequiredtospecifytheCRsystemclasseswithspatialresolutionvalues.TheCRsystemclassesinthisdocumentdonotrefertoanyparticularmanufacturersx2019;imagingplates.ACRsystemclassresultsfromtheuseofaparticularimagingplatetogetherwiththeexposureconditions,particularlytotalexposure,thescannertypeandsoftwareandthescanningparameters.ThisclassificationsystemprovidesameanstocomparedifferingCRtechnologies,asiscommonpracticewithfilmsystems,whichguidestheusertotheappropriateconfiguration,IPandtechniquefortheapplicationathand.Theclassselectedmaynotmatchtheimagingperformanceofacorrespondingfilmclassduetothedifferenceinthespatialresolutionandscattersensitivity.Therefore,thepracticeshouldalwaysuseIQIsforproofofcontrastsensitivityandspatialresolution.Thequalityfactorscanbedeterminedmostaccuratelybythetestsdescribedinthispractice.Someofthesystemtestsrequirespecialtools,whichmaynotbeavailableinuserlaboratories.SimplertestsaredescribedforqualityassuranceinPracticeE2445,whicharedesignedforafasttestofthequalityofCRsystemsandlong-termstabilityandarerecommendedaspracticalusertests,shouldtheusernothavethespecialtoolsavailableasneededforthetestsinthispractice.ManufacturersofindustrialCRsystemswillusethispractice.UsersofindustrialCRsystemsmayalsoperformthetestsandmeasurementsoutlinedinthispractice,providedthattherequiredtestequipmentisusedandthemethodologyisstrictlyfollowed.AnyalternativemethodsmaybeappliedifequivalencetothemethodsofthispracticeisproventotheappropriateCognizantEngineeringOrganization.ThepublicationofCRsystemclasseswillenablespecifyingbodiesandcontractingpartiestoagreetoparticularsystemclass,asafirststepinarrivingattheappropriatesettingsofasystem,ortheselectionofasystem.ConfirmationofnecessaryimagequalityshallbeachievedbyusingPracticeE2033.1.1Thispracticedescribestheevaluationandclassificationofacomputedradiography(CR)system,aparticularphosphorimagingplate(IP),systemscannerandsoftware,incombinationwithspecifiedmetalscreensforindustrialradiography.Itisintendedtoensurethattheevaluationofimagequality,asfarasthisisinfluencedbythescanner/IPsystem,meetstheneedsofusers.1.2Thepracticedefinessystemteststobeusedtoclassifythesystemsofdifferentsuppliersandmakethemcomparableforusers.1.3TheCRsystemperformanceisdescribedbysignalandnoiseparameters.Forfilmsystems,thesignalisrepresentedbygradientandthenoisebygranularity.Thesignal-to-noiseratioisnormalizedbythebasicspatialresolutionofthesystemandispartofclassification.Thenormalizationisgivenbythescanningapertureof100x00B5;mdiameterforthemicro-photometer,whichisdefinedinTestMethodE1815forfilmsystem......
【中国标准分类号】:F80
【国际标准分类号】:19_100
【页数】:10P.;A4
【正文语种】:英语