标准名称：	海水拖船技术要求
英文名称：	Technical requirements for sea towage
中标分类：	公路、水路运输 >> 救助、打捞与潜水 >> 救助与打捞
替代情况：	JT 6113-1986
发布日期：	1995-09-07
实施日期：	1996-03-01
首发日期：
作废日期：
出版日期：
页数：	14页

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【英文标准名称】:Acoustics-Determinationofsoundpowerlevelsofnoisesourcesusingsoundpressure-Precisionmethodsforreverberationrooms
【原文标准名称】:声学声压法测定噪声源声功率级混响室精密法
【标准号】:ISO3741-1999
【标准状态】:作废
【国别】:国际
【发布日期】:1999-08
【实施或试行日期】:
【发布单位】:国际标准化组织(IX-ISO)
【起草单位】:ISO/TC43
【标准类型】:()
【标准水平】:()
【中文主题词】:混响;测定;声学试验;声级;声学;试验;噪声(环境的);声源;声强;响度
【英文主题词】:Absorption;Acousticmeasurement;Acoustictesting;Acoustics;Airbornenoiseemitted;Calibration;Clay;Concentration;Definitions;Determination;Earprotectors;Environment;Filters;Frequencies;Handling;Hearingabilitytests;Humidity;Indications;Information;Loudnesslevels;Loudspeakers;Machines;Mathematicalcalculations;Measurement;Measuringenvironment;Measuringincertainity;Measuringinstruments;Measuringrooms;Measuringtechniques;Microphones;Noise;Noise(environmental);Noisemeasurements;Noisesources;Observation;Operatingconditions;Position;Powerlevels;Precision;Reverberation;Reverberationroommethod;Reverberationrooms;Rooms;Safetyofmachinery;Sound;Soundabsorption;Soundintensity;Soundlevel;Soundlevels;Soundpower;Soundpressure;Soundsources;Specification(approval);Standarddeviation;Surfaces;Temperature;Testing;Tests;Volume(sound)
【摘要】:1ThisInternationalStandardspecifiesadirectmethodandacomparisonmethodfordeterminingthesoundpowerlevelthatwouldbeproducedbyasourceoperatinginanenvironmentatstandardmeteorologicalconditionscorrespondingtoacharacteristicimpedanceofρc=400N·s/m(whereρisthedensityofairandcisthespeedofsound).Itspecifiestestroomrequirements,sourcelocationandgeneralrulesforoperatingconditions,instrumentationandtechniquesforobtaininganestimateofmean-squaresoundpressurelevelsfromwhichthesoundpowerlevelsofthesourceinoctaveorone-third-octavebandsarecalculatedwithagrade1accuracy.Thequantitiestobemeasuredaretime-averagedsoundpressurelevelsinfrequencybands.Thequantitiestobedeterminedaresoundpowerlevels,A-weightedandinfrequencybands.Otherquantities,whichareoptional,aresoundpowerlevelswithotherfrequencyweightingscalculatedfromthemeasurementsinfrequencybands.Thisstandarddoesnotprovidethemeanstodeterminedirectivityandtemporalvariationofsoundfromasource.Ingeneral,thefrequencyrangeofinterestincludestheone-third-octavebandswithmidbandfrequenciesfrom100Hzto10000Hz.GuidelinesfortheapplicationofthespecifiedmethodsinanextendedfrequencyrangeinrespecttolowerfrequenciesaregiveninannexC.ThisInternationalStandardisnotapplicabletofrequencyrangesabovethe10000Hzone-third-octaveband.ForhigherfrequenciestheuseofmethodsgiveninISO9295isrecommended.2ThemethodspecifiedinthisInternationalStandardissuitableforsteadynoisewithbroad-band,narrow-bandanddiscrete-frequencycomponentsasdescribedinISO12001.Thenoisemaybeemittedfromadevice,machine,componentorsub-assembly.ThisInternationalStandardisapplicabletonoisesourceswithvolumeswhicharepreferablynotgreaterthan2%ofthevolumeofthereverberationroomusedforthetest.Forsourceswithvolumesgreaterthan2%oftheroomvolume,thestandarddeviationsgivenbyTable2couldbeexceeded.
【中国标准分类号】:Z32
【国际标准分类号】:17_140_01
【页数】:32P;A4
【正文语种】:英语