空调压缩机噪声测试及其声品质客观参量分析*

针对空调压缩机辐射声场的不同场点噪声声品质的差异,采用心理学声品质参量即响度、尖锐度、总感觉噪度,对压缩机辐射声场的不同场点噪声进行声品质客观参量分析,研究压缩机场点噪声声品质客观参量值变化规律。通过特征响度研究各场点噪声响度在频域的分布,并得出压缩机各场点噪声特征响度峰值所在噪声频带。实验结果表明,对于处在压缩机不同方向上的场点,其噪声声品质客观参量值存在明显差异,但其噪声特征响度峰值却处在相同的噪声频带。研究工作为压缩机全方向降噪提供参考依据也为研究压缩机的噪声声品质探索了一种新思路。     

利用卷积网络的高速列车主观声品质预测

随着高速列车在中国的高速发展,乘客对舒适性的要求不断提高。因此高速列车内声学舒适性是一个需要研究和解决的问题。首先,该文基于声学人工头设备,获取了高速列车行驶在350 km/h速度下不同车厢、不同区域的双耳噪声样本,并对其分别开展了主观声学评价和基于响度、尖锐度、粗糙度和抖动度等参数的客观声品质分析。结果表明,350 km/h速度下高速列车车内噪声能量集中在3000 Hz以内,风挡区域是舒适性评价较差的位置,而响度是影响主观评价最大的因素。其次,利用卷积神经网络算法将主观评价结果与高速列车噪声样本相关联,建立了车内噪声主观声品质预测模型,并与基于BP神经网络的预测模型进行了对比。结果表明,基于卷积神经网络的主观声品质预测模型具有更高的预测精度,更适宜用于指导高速列车车内声学舒适性的优化设计。     

典型城市地铁站台噪声满意度*

地铁是城市轨道交通重要组成部分,地铁站台噪声对乘客身心健康有重要影响。以合肥轨道交通一号线为例,具体选择地下侧式、地下双岛式和地下岛式3个典型空间类型的地铁站台为研究对象,通过噪声测量和问卷调查相结合的方法,针对地铁在不同运营时段的乘客站台噪声满意度与噪声声元素舒适度进行评价,探讨性别、声元素舒适度以及站台噪声对乘客噪声满意度的影响。结果表明：对地铁站台噪声满意度评价,乘客性别差异不显著;在乘车高峰期时段,地铁站台广播提示声、地铁工作人员吹哨声、列车进站声和列车出站声是影响乘客站台噪声满意度主观评价的主要噪声声元素;乘客噪声满意度主观评价与站台噪声值呈强负相关,噪声值越高,满意度越低;乘客噪声满意度为可接受时的地铁站台噪声阈值,在乘车高峰期时段为74 dB(A),非高峰期时段为67 dB(A)。该文工作可为城市地铁站台噪声满意度评价及其空间结构设计提供科学参考。     

采用生理响度感知机制的车内噪声声品质预测

现有车内噪声声品质预测的响度计算中没有考虑真实人耳生理解剖结构的传声特性,因此提出了一种基于生理响度感知模型的车内噪声声品质预估方法。首先,采集两款轿车的车内噪声样本,并通过主观评价试验得到车内噪声的主观评价烦恼度。之后,整合中耳集总参数模型与耳蜗传输线模型,构建生理响度模型。然后,以生理响度模型的响度计算值为主要参数,结合尖锐度、粗糙度与车内噪声的主观评价值,通过TabNet模型构建了车辆声品质预测模型。最终,对比分析了所构建声品质模型与基于现有标准响度模型所构建的声品质模型的预测效果。结果表明,采用生理响度模型的声品质预测平均误差百分比仅有4.73%,优于采用Moore响度(6.13%)与Zwicker响度(6.94%)的声品质预测结果。此外,所构建的TabNet声品质预测模型的平均误差百分比也低于基于BP神经网络模型的平均误差百分比(7.60%)。采用生理响度模型的TabNet声品质预测能够提高车内噪声声品质客观评价的准确率。     

地上地下商场声环境满意度评价与比较研究

为了解地上地下商场消费者对声环境的感受及不同,对哈尔滨四个典型商场进行了现场调研与主观评价。利用主因子法分析了声音识别,结果表明音乐声是主要成分。回归分析表明声环境满意度评价与测试声压级LAeq有较强的相关性,声音总体评价为"一般"。声环境满意度评价,整体上地上商场略好于地下商场,空间开敞、环境较好则评价也较好;同一商场较低楼层不如较高楼层;不同空间则是扁平空间优于长空间、营业空间不如休闲空间。     

车内噪声品质主客观评价探究式教学实验

基于探究式教学思想,针对"汽车噪声分析与控制技术及应用"课程,面向车辆工程专业学生设计了汽车车内噪声品质主客观评价探究式教学实验,且开发了车内噪声心理声学评价指标分析计算的辅助教学软件,可在实际汽车内先通过丹麦B&K公司3560型噪声采集系统进行实验测试,然后在实验室内回放进行车内声品质的主客观分析评价. 实验过程中学生在了解车内噪声心理声学主、客观评价指标的基础上,主动参与车内噪声测量和主、客观评价两部分实践环节,促进对理论课相关知识的理解.     

采用响应面回归的汽车多属性声品质预测方法*

单一主观评价分数无法准确描述人耳对声品质的多属性偏好特征。该文在多属性声品质试验数据的基础上,以愉悦度、平顺度和驾驶乐趣的主观评价分数为因变量,通过相关分析筛选出响度、尖锐度和A计权声压级3个主要自变量,引入响应面回归方法,分别建立因变量与自变量之间的预测模型,通过与多元线性模型和BP神经网络模型对比验证了精度。最后,建立多属性主观评价分数之间的量化映射模型。该研究可为多属性汽车声品质的优化控制提供参考。     

一种声驻波演示装置

驻波是一种重要的波的干涉现象.两个振幅相同的相干波,在同一直线上,沿相反方向传播时,叠加后成为驻波.在波形上,驻波的波节和波腹的位置始终是不变的,给人"驻立不动"的印象,但它的瞬时值是随时间而改变的.声音是一种可以听得到,却摸不着的物质,新设计的一种声驻波演示装置可以让声音跳起舞来,通过泡沫球的形态变化来观赏活泼跳跃的...     

一种声图直航段数据自动提取及镶嵌的方法

声图镶嵌是利用成像声纳获得声图进行测深、水下地形地貌测绘的重要应用方向。常见的成像声纳多要求声纳载体做直线运动,而实际应用中载体有大量转弯的情况。为此提出了一种声图直航段数据自动提取方法,该方法首先利用Douglas-Peucker算法对声纳航迹进行抽稀处理,之后利用相邻抽稀点之间的距离判断数据是否为直航段,最后将直航段图像提取出来。获得直航段数据后,利用地理信息对声图进行镶嵌处理。对千岛湖湖底地貌图像进行了处理,获得了较好的镶嵌结果。     

一种新的光谱分析方法——声致发光法

本文介绍了一种新型的原子发射光谱分析方法－声致发光法及其在分析化学与环境监测中的应用。     

A method to accurately measure and respond to an underwater sound pulse in a wide dynamic range

I.IntroductionTomeasurethesound1evelofanundcrwatersoundpulsewithunknownamplitudeisofimportanceinunderwaterapp1ication.Forinstancc,asimu1ationsystemusedtointerfcresomesonarmusthavesuchfunction,whichhastobeabIctomeasurethesoundlcvelatreceivingpointandretransmitasimulatcdsignalwithrequircdsoundlcvelafterpropcrprocessing.Itisdifficultforanorma1peakorthresho1ddetectortocompletethistask.Thereasonforthisisthattherangeofthesignalamp1itudercaches7O-8odBandthereissomedistortionofsignalwaveform,inaddit…     

Reception plate method for characterisation of structure-borne sound sources in buildings: Assumptions and application

A method for characterisation of structure-borne sound sources is proposed and investigated for the special but common case of machines in heavy-weight homogeneous building structures. The method is based on the concept of the reception plate where the total structure-borne sound power from the machine under test is assumed equal to the power dissipated by a plate attached to the machine. The method is relatively simple and allows comparison of sources on a power basis, and of tests results at different laboratories. Additionally the data obtained is in a form suitable for transformation into an installed structure-borne power and thence for the resultant sound pressure generated in buildings. The method is validated by cross-spectral and mobility methods. A study of the uncertainty of the power estimate was performed by numerical modelling and measurement.     

计入地面附加衰减的声屏障插入损失估算方法*

基于理论推导和计算,给出了公路声屏障声学设计中,在考虑地面附加衰减情况下计算插入损失的方法。该方法综合考虑了有限长线声源无限长声屏障绕射声衰减量、有限长线声源地面衰减量及遮蔽角对插入损失的影响。通过与《声屏障声学设计和测量规范》（HJ/T90-2004）的计算结果的对比,验证了本文所给方法的精确性及可行性,并对规范所给地面衰减修正量进行了商榷。最后,给出了当预测点位于有限长路段中央法线上时,通过计算线声源地面衰减量得到计算插入损失所需参数值,再计算插入损失的简便方法。本研究为存在地面附加衰减情况下有限长声屏障插入损失计算提供了一个新的参考方法。     

环境声质量分类评价体系的实验研究

本文针对我们已提出的环境声质量分类评价体系及与之相应的定量评价指标ESQ，进行了实验验证。研究结果表明：所提分类评价体系和ESQ是有效的，二者的评价结果是一致的。最后，针对整个实验研究过程进行了讨论，并指出有待进一步研究和改善的方面。     

Characterizing the sound quality of air-conditioning noise

The aim of the psychoacoustic study presented here was to characterize listeners' preferences for a set of sounds produced by different brands and models of indoor air-conditioning units. In addition, some synthetic sounds, created by interpolation between recorded sound samples, were integrated into the set. The multidimensional perceptual space and the corresponding physical space representative of the sound set were determined with multidimensional scaling (MDS). Then the preferences for different classes of listeners were related to the physical space. The best spatial model yielded by the MDS had three common dimensions and specificities. The three dimensions are correlated with the ratio of the noisy part of the spectrum to the harmonic part (NHR), with the spectral center of gravity (SC) and with loudness (N). Two classes of listeners can be distinguished in terms of preference. For one, preference varied primarily with loudness, whereas for the other it varied more with SC and NHR. However, for one class the preference grew with the parameter NHR, while it decreased for the other class. The results replicate under different laboratory conditions and indicate the usefulness of this sound quality assessment approach for characterizing appliance noises.     

Sound quality evaluation of the booming sensation for passenger cars

Automotive booming noise due to powertrain occurs when pure or narrow band tones related to the firing frequency of engine and its harmonics excite the passenger cavity, which entails a prominent increase of sound intensity. The booming sensation has been considered as very important to the acoustic comfort of passengers. In this study, a sound quality index which can objectively evaluate the booming sensation was derived. Because of the tonal nature of powertrain booming noise, subjective pitch was employed to find only aurally relevant tonal components which influence booming sensation as well as loudness. Using the empirical data and the frequency difference limen for just-noticeable change of booming sensation obtained from the listening test, an existing pitch extraction algorithm could be modified. The modified pitch model was applied to the interior noises of accelerating passenger cars together with a loudness analysis for representing the objective features of booming feeling. Subjective tests using the magnitude estimation method were conducted to evaluate the degree of booming sensation. Finally, booming strength was proposed for quantifying the booming sensation, which was validated by subjective results. The correlation coefficient between the derived booming strength and the degree of booming sensation obtained by the subjective test was 0.926.     

主观评价实验中声音样本剂量值的度量方法

提出了一种基于对播放时长短时化处理的声音样本剂量值度量方法, 确定了十一种剂量值指标用于衡量具有固定播放时长声音样本的剂量值, 并分析了可能影响声音样本剂量值的主要因素; 随后, 对大量声音样本以各种指标度量的剂量值矩阵进行了聚类分析, 获得了三种类型的声音样本剂量值度量指标, 并确定了不同指标类型中的代表性指标; 最后, 分析了声音样本采用不同类型指标度量的剂量值与评价者对声音样本主观烦恼度等级之间的关系. 为利用主观评价实验进行固定播放时长声音样本作用下的主观烦恼度研究奠定了基础. 关键词： 声暴露量 烦恼度 声音样本 主观评价     

使用脉冲声和矢量传声器的现场测量吸声系数

使用不同声源利用矢量传声器对毛毡材料进行现场吸声系数测试,研究了不同背景下不同声源的抗噪能力。矢量传声器可以同时测得声压和质点振速信号,进而可计算得到阻抗,利用自由空间和材料表面的阻抗可计算得到材料的吸声系数。在此次实验中,使用不同声源分别在无干扰和有一白噪声干扰源的两种情况下进行测试。结果表明,使用对数扫频脉冲和巴特沃斯脉冲测试所得的吸声系数曲线更平滑,说明脉冲声可以有效降低环境反射的影响,在高噪声背景下使用对数扫频脉冲测试所得的结果基本没有受到背景噪声的影响,说明对数扫频脉冲的抗噪能力更强。因此,使用对数扫频脉冲作为声源进行测试可有效减弱环境反射和背景噪声的影响。     

一种双正交心音小波的构造方法

为了提高小波分析在心音信号处理中的性能, 在分析小波构造理论的基础上, 构造了一种专门用于心音信号处理的小波基. 首先提出一种构造滤波器长度为偶数的紧支撑双正交小波的一般方法; 然后根据心音信号的特点, 讨论心音小波的构造原则和一种基于心音 小波族的心音信号合成模型, 并且在此基础上构造出心音小 波. 为了突出使用心音小波处理心音信号的先进性和实用性, 对心音小波进行了比较全面的理论和数值仿真分析. 实验结果表明, 相比常用的db, bior系列小波, 运用心音小波对心音信号进行处理, 能够获得更好的去噪效果、 更精确的心音分类信息以及更小的重构误差率, 为心音特征提取和身份识别的深入研究提供了一种新方法, 在表征心音个体特征的细节方面具有积极的意义. 本文根据应用对象设计专用小波的方法也为工程应用中小波基的选择提供了一种新途径. 关键词： 双正交小波 心音小波 构造方法 心音合成模型     

Sound radiation and sound quality characteristics of refrigerator noise in real living environments

The characteristics of various types of refrigerator noise were investigated in an anechoic chamber and in a real living environment - a 100 m² apartment which is a common size in Korea. It was found that the sound pressure level of the refrigerator noise in the real living room was about 10 dB higher than the level in the anechoic chamber at the same position (1 m in front of refrigerator). In addition, a tolerance level for refrigerator noise was determined by subjective evaluation experiments. Refrigerator noise was presented by a loudspeaker placed in the kitchen where the refrigerator is normally located. Level 2 responses to the subjective evaluation (“hardly perceivable”) corresponded to a sound pressure level of about 26 dB(A), for which 90% of participants were satisfied with the level of refrigerator noise. A semantic differential test using various adjectives was also conducted to evaluate the sound quality of refrigerator noise. With the semantic differential and the factor analysis, adjectives used in this experiment were grouped into three factors. From the results of correlation and multiple regression analyses on the psychoacoustical parameters and subjective evaluations of 30 kinds of refrigerators, sound quality index which predict the subjective rating score were proposed.