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【英文标准名称】:Magneticresonanceequipmentformedicalimaging-Part1:Determinationofessentialimagequalityparameters
【原文标准名称】:医疗成象磁共振设备.第1部分:测定实际成象质量参数
【标准号】:IEC62464-1-2007
【标准状态】:现行
【国别】:国际
【发布日期】:2007-01
【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/SC62B
【标准类型】:()
【标准水平】:()
【中文主题词】:验收检验;验收试验;稳定性试验;定义;诊断(医学);电气工程;电医学;图例;图像增强器;图象质量;成象;检验;磁共振设备;测量技术;医疗器械;医疗放射照相术;医学科学;医疗技术学;质量;质量保证;射线摄影;辐射摄影术;辐射学;射线检查;额定值;安全工程;扫描方法;试验;试验条件;X-射线;X-射线仪;X-射线设备;X-射线检验;X-射线技术
【英文主题词】:Acceptanceinspection;Acceptancetests;Constancytesting;Definitions;Diagnosis(medical);Electricalengineering;Electromedicine;Illustrations;Imageintensifiers;Imagequality;Imaging;Inspection;Magneticresonanceequipment;Measuringtechniques;Medicalequipment;Medicalinstruments;Medicalradiography;Medicalsciences;Medicaltechnology;Quality;Qualityassurance;Qualityrequirements;Radiographs;Radiology;Radioscopy;Ratings;Safetyengineering;Scanningmethods;Testing;Testingconditions;X-ray;X-rayapparatus;X-rayequipment;X-rayexamination;X-raytechnique;X-rays
【摘要】:ThisinternationalstandardspecifiesmeasurementproceduresforthedeterminationofmanyessentialmedicalMREQUIPMENTimagequalityparameters.Measurementproceduresasaddressedinthisstandardaresuitablefor:-qualityassessmentintheACCEPTANCETEST;-qualityassuranceintheCONSTANCYTEST.Inaddition,themeasurementproceduresspecifiedinthisstandardmayalsobeusefulfortypetests,althoughthatisnotanobjectiveofthisstandard.Thisstandarddoesnotaddress:-requiredlevelsofperformanceforACCEPTANCETESTandCONSTANCYTEST;-imagequalityassessmentofhighfieldMREQUIPMENTgreaterthan4T,ifnototherwisestated;-imagequalityaffectedbyMR-compatibilityissues;-specialdiagnosticproceduressuchasflowimaging,perfusion,diffusion,radiotherapyandimage-guidedtherapyapplications;-typetests.ThescopeofthisstandardisalsolimitedtomeasuringimagequalitycharacteristicsinTESTDEVICES,notinPATIENTimages.Themeasurementproceduresspecifiedinthisstandardaredirectedto:a)MANUFACTURERS,whocandemonstratecompliancebyperformingacceptanceandconstancymethodsasdescribedbythisstandard,b)testhouses,whichcanconfirmperformanceofMREQUIPMENTusingmethodsdescribedinthisstandard,c)regulatoryauthorities,whocanreferencethisstandard,andd)RESPONSIBLEORGANISATIONSwhowanttoperformACCEPTANCEandCONSTANCYTESTSusingmethodsdescribedinthisstandard.Theessentialimagequalityparametersandmeasurementmethodologiesdefinedinthisstandardare:-SIGNAL-TO-NOISERATIO,-UNIFORMITY,-SLICETHICKNESSandSLICEPROFILE,-GEOMETRICDISTORTION,-SPATIALRESOLUTION,and-ghosting.Thisstandarddescribesthepreferredmeasurementprocedures.ItalsodescribesalternativemethodsinAnnexA.Thepreferredtestmethodsmaybesubstitutedwiththealternativemethods.Ifnecessary,othermethodsnotdescribedinthisstandardmaybeused,providedtheseothertestmethodsaredocumentedandvalidatedagainstthemethodsdescribedinthestandard.Validationofothertestmethodsrequiresananalysisoftestsensitivitytothesameparameterofinterestandananalysisoftheinsensitivityofthetesttootherunrelatedparametersandshoulddemonstrateasimilar,orbetter,levelofsensitivitytothesameparameterofinterestandasimilar,orbetter,levelofrobustnessagainstunrelatedparameters.Allmethodsshallproducequantitativeresults.Therationaletothepreferredandalternatemethods,andtheirpitfalls,aredescribedinAnnexB.ThisstandardalsopresentsrequirementsforCONSTANCYTESTSsuitableforMREQUIPMENTqualityassuranceprogramsconcerningessentialimagequalityparameters.TherearenopreferredCONSTANCYTESTmethods,toprovideflexibilityinusingexistingautomatedprocedureswhereavailable,butsuggestedexamplesoftestmethodsarefoundinAnnexA.Ifnecessary,otherCONSTANCYTESTmethodsnotdescribedinthisstandardmaybeused.SincetheneedsofRESPONSIBLEORGANISATIONS'qualityassuranceprogramsmayvary,RESPONSIBLEORGANISATIONSareencouragedtodeterminethenecessaryscopeoftests,qualityofthetests,andthesensitivityofthedataanalysisetc.Thisstandardplacesanemphasisonconsistentlyrepeatable,automatedmeasuringtoolsthatfacilitatetrendanalysisandthefrequentquicktestingofasmallsetofimportantparameterswhicharesensitivetotheoveralloperatingcharacteristicsoftheMREQUIPMENT.
【中国标准分类号】:C43
【国际标准分类号】:11_040_50;35_240_80
【页数】:157P;A4
【正文语种】:英语


【英文标准名称】:StandardTestMethodforMeasurementofHydrogenEmbrittlementThresholdinSteelbytheIncrementalStepLoadingTechnique
【原文标准名称】:用增长载荷技术测量钢中氢脆性的标准试验方法
【标准号】:ASTMF1624-2009
【标准状态】:现行
【国别】:美国
【发布日期】:2009
【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】:F07.04
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:decreasingloadingrate;delayedbrittlefailure;displacementcontrol;fasteners;hydrogenembrittlementthreshold;hydrogeninducedstresscracking;risingstepload;slowstrainrate;Acceleratedaging/testing--metallicmaterials;Constantrate-of-ext
【摘要】:Thistestmethodisusedforresearch,design,serviceevaluation,manufacturingcontrol,anddevelopment.Thistestmethodquantitativelymeasuresstressparametersthatareusedinadesignorfailureanalysisthattakesintoaccounttheeffectsofenvironmentalexposureincludingthatwhichoccursduringprocessing,suchasplating(8)(ASTMSTP962).Forplatingprocesses,thevalueofx03C3;th-IHEisusedtospecifyquantitativelythemaximumoperatingstressforagivenstructureorproduct.Forqualitycontrolpurposes,anacceleratedtestisdevisedthatusesaspecifiedloadingrate,whichisequaltoorlowerthantheloadingratenecessarytodeterminethethresholdstress(see8.1).Forfasteners,thevalueofx03C3;th-IHEisusedtospecifyquantitativelythemaximumstressduringinstallationandinservicetoavoidprematurefailurecausedbyresidualhydrogeninthesteelasaresultofprocessing.Forfasteners,thevalueofx03C3;th-EHEisusedtospecifyquantitativelythemaximumstressduringinstallationandinservicetoavoidfailurefromhydrogenabsorbedduringexposuretoaspecificenvironment.Tomeasuretherelativesusceptibilityofsteelstohydrogenpickupfromvariousfabricationprocesses,asingle,selected,discriminatingrateisusedtoranktheresistanceofvariousmaterialstohydrogenembrittlement.AnnexA1describestheapplicationofthisstandardtestmethodtohydrogenembrittlementtestingoffasteners.1.1Thistestmethodestablishesaproceduretomeasurethesusceptibilityofsteeltoatime-delayedfailuresuchasthatcausedbyhydrogen.Itdoessobymeasuringthethresholdfortheonsetofsubcriticalcrackgrowthusingstandardfracturemechanicsspecimens,irregular-shapedspecimenssuchasnotchedroundbars,oractualproductsuchasfasteners(2)(threadedorunthreaded)springsorcomponentsasidentifiedinSAEJ78,J81,andJ1237.1.2Thistestmethodisusedtoevaluatequantitatively:1.2.1Therelativesusceptibilityofsteelsofdifferentcompositionorasteelwithdifferentheattreatments;1.2.2Theeffectofresidualhydrogeninthesteelasaresultofprocessing,suchasmelting,thermalmechanicalworking,surfacetreatments,coatings,andelectroplating;1.2.3Theeffectofhydrogenintroducedintothesteelcausedbyexternalenvironmentalsourcesofhydrogen,suchasfluidsandcleanersmaintenancechemicals,petrochemicalproducts,andgalvaniccouplinginanaqueousenvironment.1.3Thetestisperformedeitherinair,tomeasuretheeffectifresidualhydrogenisinthesteelbecauseoftheprocessing(IHE),orinacontrolledenvironment,tomeasuretheeffectofhydrogenintroducedintothesteelasaresultoftheexternalsourcesofhydrogen(EHE)asdetailedinASTMSTP543.1.4Thevaluesstatedinacceptableinch-poundunitsshallberegardedasthestandard.Thevaluesstatedinmetricunitsmaynotbeexactequivalents.Conversionoftheinch-poundunitsbyappropriateconversionfactorsisrequiredtoobtainexactequivalence.1.5Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.
【中国标准分类号】:H22
【国际标准分类号】:77_040_10
【页数】:12P.;A4
【正文语种】:英语