ISO/IEC 14496-3-2001 信息技术音频-可视对象的编码第3部分:音频
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来源:标准资料网
【英文标准名称】:Informationtechnology-Codingofaudio-visualobjects-Part3:Audio
【原文标准名称】:信息技术音频-可视对象的编码第3部分:音频
【标准号】:ISO/IEC14496-3-2001
【标准状态】:作废
【国别】:国际
【发布日期】:2001-12
【实施或试行日期】:
【发布单位】:国际标准化组织(ISO)
【起草单位】:ISO/IECJTC1
【标准类型】:()
【标准水平】:()
【中文主题词】:编码(数据转换);视频信号;MPEG;尺寸;编码;计算机制图;图像处理;信息技术;定义;客体;数据处理;代码表示;信息交换;多媒体;声信号
【英文主题词】:
【摘要】:
【中国标准分类号】:L81
【国际标准分类号】:33_160_01;35_040
【页数】:
【正文语种】:英语
【英文标准名称】:Textiles-Testingthreads-Determiningthetwistingofthreadsbyuntwisting/retwistingwithadoublere-test.
【原文标准名称】:纺织品.纤维试验.用二次对比试验退捻加捻测定纤维捻度.
【标准号】:NFG07-079-2011
【标准状态】:现行
【国别】:法国
【发布日期】:2011-05-01
【实施或试行日期】:2011-05-13
【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】:
【摘要】:
【中国标准分类号】:W55
【国际标准分类号】:59_060_01
【页数】:14P;A4
【正文语种】:其他
【英文标准名称】:StandardTestMethodforCharacterizingtheEffectofExposuretoEnvironmentalCyclingonThermalPerformanceofInsulationProducts
【原文标准名称】:暴露于环境循环对绝缘产品热性能特征影响的标准试验方法
【标准号】:ASTMC1512-2007
【标准状态】:现行
【国别】:
【发布日期】:2007
【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】:C16.33
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:环境测试;曝露;绝缘;污染控制;试验方法;热分析;绝热材料;隔热;热应力
【英文主题词】:environmentalcycling;thermalinsulation
【摘要】:Exposingaspecimentoconditionsofone-directionalenvironmentalcyclingcanincreaseitsmoisturecontentuntiladecreaseinmaterialpropertiesoccurs(ataspecificnumberofcycles).Suchatestcouldbeinappropriateduetothenumberofcyclesrequiredtocauseadecreaseinmaterialpropertiessinceproductperformanceissuesoftenariseonlyaftermanyyearsofexposure.Theuseofapreconditioningprocedureisnotintendedtoduplicateexpectedfieldperformance.Ratherthepurposeistoincreasethemoisturecontentoftestmaterialspriortosubjectingtothemtoenvironmentalcycling.Themostimportantaspectofthepreconditioningprocedureisnon-uniformmoisturedistributioninthespecimen.Theheatflowisonedirectionalcausingmoistureflowtowardsthecoldsideresultinginzonesofdrymaterialonthewarmsideandhighmoisturecontentonthecoldside.(Whetherthehighmoisturecontentzoneislocatedrightatthecoldsurfaceofthespecimenoratsomedistancefromthissurfacedependsupontemperatureoscillationandabilityofthecoldsurfacetodryoutwards).Becausethepreconditioningprocedureinvolvesthermalgradient,thispreconditioningprocedureresultsinadistributionofmoisturecontentthatmayoccurunderfieldexposureconditions.However,theresultingmoisturecontentmaydiffersignificantlyfromthatwhichmaybedemonstratedintypicalproductapplications.Thepreconditioningresultsinaccumulationofmoistureinthethermalinsulationresultingfromthesimultaneousexposuretoadifferenceintemperatureandwatervaporpressure.Thistestmethodisnotintendedtoduplicatefieldexposure.Itisintendedtoprovidecomparativeratings.Asexcessiveaccumulationofmoistureinaconstructionsystemmayadverselyaffectitsperformance,thedesignershouldconsiderthepotentialformoistureaccumulationandthepossibleeffectsofthismoistureonthesystemperformance.1.1Thistestmethodisapplicabletopreformedorfieldmanufacturedthermalinsulationproducts,suchasboardstockfoams,rigidfibrousandcompositematerialsmanufacturedwithorwithoutprotectivefacings.SeeNote0Thistestmethodisnotapplicabletohightemperature,reflectiveorloosefillinsulation.Note0Iftheproductismanufacturedwithafacer,testproductwithfacerinplace.1.2Thistestmethodinvolvestwostages:preconditioningandenvironmentalcycling.Duringthefirststage,25mm(1in.)thickspecimensareusedtoseparatetwoenvironments.Eachoftheseenvironmentshasaconstantbutdifferenttemperatureandhumiditylevel.Duringtheenvironmentalcyclingstage,specimensalsodividetwoenvironmentsnamelyconstantroomtemperature/humidityononesideandcyclingtemperature/ambientrelativehumidityontheotherside.1.3Thistestmethodmeasurestheabilityoftheproducttomaintainthermalperformanceandcriticalphysicalattributesafterbeingsubjectedtostandardizedexposureconditions.Acomparisonismadebetweenmaterialpropertiesforreferencespecimensstoredinthelaboratoryforthetestperiodandspecimenssubjectedtothetwo-stagetestmethod.Toeliminatetheeffectofmoisturefromthecomparison,thematerialpropertiesofthelattertestspecimensaredeterminedaftertheyhavebeendriedtoconstantweight.Theaveragevaluedeterminedforeachofthetwosetsofspecimensisusedforcomparison.1.4Differentpropertiescanbemeasuredtoassesstheeffectofenvironmentalfactorsonthermalinsulation.Thistestmethodrequiresthatthermalresistancebedeterminedbaseduponanaverageforthreespecimensmeasuredaftercompletingthetest.Secondaryelementsofthistestmethodincludevisualobservationssuchascracking,delaminationorothersurfacedefects,aswellasthechangeinmoisturecontentaftereachofthetwostagesofexposur......
【中国标准分类号】:K15
【国际标准分类号】:13_020_60
【页数】:5P.;A4
【正文语种】:
