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简介：0.General;1.PhysicalAcoustics;2.UnderwaterSound;3.MechanicalVibrationandShock;4.NoiseandFourgroupsofguineapigswereexposedtobudsound(3h,1kHz.125dBSPL).Onegroupinhaledairascontrol(C-group),andtheothergroupsingaled2ATAhyperbaricoxygen(HBO)for30minuteseachtime.Thesethreegroupswerecalled,respectively,preventiongroup(P-group)inhalingHBOoncebeforeexposure,treatmentgroup(T-group)inhalingHBOdailyfor14daysafterexposure,andprevention-treatmentgroup(PT-group)inhalingHBOoncebeforeexposureandonceadayfor14daysaf-terexposure.Afterexposure.thethresholdofthecorticalauditorypotentialevokedbyclickroseinallani-mals.HearinglossofC-groupwastheseverest,upto70dB,whilethoseofP-groupandPT-groupwhere53dBand51dB,respectively(p<0.01,comparedwiththatofC-group).HearinglossofT-groupwas68.5dB.Smilarphenomenawerefoundinthemeasurementbytone-burst.Theaboveaspectslasted21daysuntiltheseanimalswerekilled.Theaveragetraumalengthof

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简介：0.General;1.PhysicalAcoustics;2.UnderwaterSound;3.MechanicalVibrationandShock;4.NoiseandNoiseControl;5.Ultrasonics;6.SpeechAsousticsandSpeechCommunication;7.Physio-logicalAcoustics;8.ArchitecturalAsoustics;9.Electroacoustics;10.AcousticalMeasurementandInstrumentation;11.AmosphericAcoustics;12.Geoacoustics;13.Bioacoustics;14.MusicalAcous-tics;15.SignalProcessing

简介：0.General;1.Physicalacoustics;2.Underwatersound;3.Mechanicalvibrationandshock;4.Noiseandnoisecontrol;5.Ultrasonics;6.Speechacousticsandspeechcommunication;7.Physio-logicalacoustics;8.Architecturalacoustics;9.Electroacoustics;10.Acousticalmeasurementandinstrumentation;11.Atmosphericacoustics;12.Geoacoustics;13.Bioacoustics;14.Musicalacoustics;15.Signalprocessing.

简介：声学的历史很长，但是为现代声学，它仅仅在贝尔的家以后从第19世纪的结束被开始，萨宾是工作。在中国的现代声学甚至以后被开发。对在缅甸人的大刀的中国的现代声学的发展的主要贡献--尤马阿和他的学术成就在这份报纸被介绍。它被看那把缅甸人的大刀--在中国是正常模式理论和现代声学的创始人之一的尤马阿在开发现代声学起了一个重要作用。MAA的科学哲学和他的社会活动的一些初步的研究也在这份报纸被讨论。

简介：ARevisedEditionofthenow-classical1971texteditedbyL.Beranek,NoiseandVibrationControl,hasbeenpublishedbytheInstituteofNoiseControlEngineering.NoiseandVibrationControlisofgreatvaluetodesignandsafetyengineers,consultants,scientists,architects,governmentresearchers,publicofficialsandothersconcernedwiththecontrolofnoiseemittedbymachineryandwithcontrolofenvironmentalnoiseinbuildings,intheworkplace,nearairportsandhighways,andinthecommunity.This

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简介：TostudythespatialdifferenceofoceanambientnoiseinoffshoreChinaandrevealitsgenerationmechanism,thedifferencebetweenthenoiselevel(NL)oftwostationsiscomparedbasedonlong-termobservationdatacollectedinthesameseason.Consideringtheinfluenceofunderwateracousticchannelsandthecharacteristicsofnoisesources,thetransmissionlosslevel(TL)fromtheportshipnoisesourcestothemeasuringstationisanalyzedanditshowsastrongcorrelationbetweenthetransmissionlossdifference(TLD)andnoiseleveldifference(NLD)atthebandof50-500Hz.Atthesametime,theanalysisofshipnoisesourcelevel(SL)presentsadifferenceabout20dBbetweenthetwoports,correspondingtothevariationoftheshipdensitybeforeandduringthefishingmoratorium.Theresultsprovethattheambientnoiseiscloselyrelatedtoshipnoisesourcesatthisfrequencyband,andthenoisedifferencebetweenthetwostationsresultsfromthetransmissionlossandtheshipnoisesources.

简介：ProfessorBeranektalkedaboutthesoundqualitiesofconcerthall.The58famousconcerthallsintheworldweregradedaccordingtothesubjectivecomparisonfromtheprofessionalmusiciansandmusiclovers.Sixmeasurableobjectiveparameterswereproposed.Therankingaccordingtotheseparameterswerepresented.

简介：Byinvestigatingtheeffectsondeepoceanambientnoiseoftyphoon'KAI-TAK'whichpassedthenorthareaoftheSouthChinaSea,itisshownthatthewindspeed,therainfallintensityandthelongwaveswellcausedbytyphoonaffecttheoceanambientnoisesignificantly.Thecorrelationbetweentheoceanambientnoiseandthewindspeedduringthetyphoonismuchbetterthanthatinthenon-typhoonperiodinthesameBeaufortscale.Analysisofthecorrelationbetweenthe415hoceanambientnoisemeasureddataandwindspeedshowsthat,whenthefrequencyisgreaterthan300Hz,thecorrelationcoefficientbetweentheoceanambientnoiseandthewindspeedisgreaterthan0.5,achievingamoderatecorrelation;whenthefrequencyisgreaterthan630Hz,thecorrelationcoefficientisbetween0.8and0.9,achievingahighdegreeofcorrelation.Thecorrelationbetweentheoceanambientnoiseandthewindspeedisbetterthanthatbetweentheoceanambientnoiseandthesignificantwaveheightwhenthefrequencyisgreaterthan300Hz.Thecorrelationbetweentheoceanambientnoiseandthewindspeedininfrasonicbandfrom10Hzto20HzispoorintheSouthChinaSea,becausetheshippingisbusyinthisseaareaandtheoceanambientnoiseiscontaminatedbytheshipnoiseevenduringthetyphoon.

简介：O.General;1.Physicalacoustics;2.Underwatersound;3.Mechanicalvibrationandshock;4.Noiseandnoisecontrol;5.Ultrasonics;6.Speechacousticsandspeechcommunication;7.Physiologicalacoustics;8.Ar-chitecturalacoustics;9.Electroacoustics;10.Acousticalmeasurementandinstrumentation;11.Atmosphericacoustics;12.Geoacoustics;13.Bioaoustics;14.Musicalacoustical;15.Signalprocessing.

简介：AmethodtoidentifycomplexYoung’smodulusofviscoelasticmaterialsusingforcedlongitudinalvibrationofslenderrodsisproposed.Themethoddiffersfromthebeamone.Experimentaltestswerecarriedoutatroomtemperaturewithdifferentlengthsin108mm,100mm,90mm,83.5mm,80mm.74.5mm,70mmforthepolycarbonatebars,andthecurvesofratiosA2/A1betweentwoendsofaviscoelasticbarversusfrequenciesareobtained,furthermore,thecorresponding3dBbandwidthandthestorageandlossmoduluscanbecalculated.SufficientnumberofobtainedcomplexYoung’smodulusatdifferentfrequencyallowsustocalculateotheronesusingtheleastsquaremethod.Ifthestepofthetestedfrequencyis5Hz,themaximumerrorofresultscanbelessthan6%.Bycomparisonwiththemeasurementmethodswhichthepreviousliteraturementioned,thisnewmethodsimplifiesthecalculation,andthephysicalmeaningappearsapparentlyandclearly.

简介：BasedonthenoisesurveyinChina,theformula（H′=H+N-HN/120）ofISO/DIS1999.2（"Acous-tics-DeterminationofOccupationalnoiseexposureandestimationofnoise-inducedhearingimpairment,1985）wasappliedtothecalculationofthehearingthresholdlevelassociatedwithageandnoise（HTLAN）ofthenoise-impairedpeople.AccordingtotheGaussciandistribution,whenthenoise-exposurelevelLEX8hwas85,90,95,100dBandthehearingthresholdfrequencyisfrom0.5kto6kHz,theHTLANofnoise-exposedpeoplewithdifferentdurationofexposureanditsrelationvaluestothehearingthresholdfrequencyassociatedwithage（HTLA）wereobtained.TheISO/DIS1999.2hasbeenprovedtobeapplicableinChina.

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简介：基于液体动力学，热转移和声学的结果，一个计算液体动力学(CFD)方法被利用在一根Rijke管子内学习声学的特征和自我刺激的跳动机制。为了避免解决有限振幅的站的荒谬的边界条件，在Rijkethermo声学的系统飘动，在流动领域里当模特儿的模拟，它联合了有它的外层空间的管子内部，被执行代替传统的方法处于良好的竟技状态内部流动地数字调查。为在包括在热来源，摆动压力和摆动速度附近的空气的不稳定的热上的关系的精力方程的热来源的一个假设被介绍。为了反映Rijke的本质，尖叫，自我刺激的摆动上的模拟借助于它压力，速度和温度的自己的跳动被进行。这个方法能使集中过程稳定并且有效地避免分叉。自我刺激的Rijke管子的物理现象被分析。而且，Rijke管子的自我刺激的摆动上的机制是这个方法上的explained.Based，关于有不同尺寸和嘴的不同形状的Rijke管子的声学的特征的比较研究被执行。模拟结果令人满意地同意了试验性的数据。结果证明这数字模拟能被用来为Rijke管子的设计申请学习嘴的健全压力。