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1.
水下噪声及其控制技术进展和展望   总被引:10,自引:0,他引:10       下载免费PDF全文
何祚镛 《应用声学》2002,21(1):26-34
本文主要介绍近年来船舶行业水下噪声研究进展情况,包括水下噪声形成机理和预报;水下噪声控制技术;水下噪声近代测量分析技术,并提出对水下噪声研究工作的展望。  相似文献
2.
用声场空间变换识别水下噪声源   总被引:7,自引:0,他引:7       下载免费PDF全文
何元安  何祚镛 《应用声学》2000,19(2):9-13,30
本文提出利用声场空间变换技术进行噪声源的分离与识别。  相似文献
3.
半混响环境中水下结构辐射声功率测量   总被引:4,自引:0,他引:4       下载免费PDF全文
本文参照空气声学的方法,在水池的半混响环境中,测量了两个相似加肋圆柱壳模型的水下辐射声功率,并利用声辐射的理论相似关系进行校验,在高频段测量偏差为1-2dB。  相似文献
4.
《应用声学》2002,21(1):2-2
在新世纪的第二个春天,我们迎来了《应用声学》创刊20周年。本刊新老工作人员与广大读者、作者、审者朋友们同喜同庆。 应时代的需求,《应用声学》创刊于1982年1月14日。20年来,与祖国改革开放的时代同呼吸共命运。在党的出版方针指引下,遵循办刊宗旨,《应用声学》经历了创业、成长、提高的历程,并在实践中逐步形成自己的特色,日渐为声学领域的广大读者所接受、肯定。去年,在我国正在出版的近万种中文期刊中确定了1568种期刊为核心期刊,《应用声学》名列其中。随着现代信息技术的发展,本刊在出版印刷版的同时,增…  相似文献
5.
本文在分析突体马蹄涡和湍流脉动压力特性的基础上,在中国船舶科学研究中心03B水筒,试验比较了不同剖面线型的突体模型流动噪声,降噪效果3-5dB,提出了突体部面低噪声设计的实验依据和具体方法。  相似文献
6.
刘献铎 《应用声学》1987,6(1):45-45
中国声学学会水声学分科学会成立大会暨学术交流会于1986年9月10日至13日在厦门召开.有近150位代表参加了会议.中国声学学会名誉理事长汪德照教授、理事长应崇福教授也出了席.杨士莪教授向大会报告了水声学分科学会成立的筹备情况. 会议收到论文摘要140余篇,分为特邀报告,水声物理,信号处理,水声仪器和测量方法,水下噪声,换能器、阵和声辐射,其它等七个部分.除特邀报告在全体  相似文献
7.
本遥测浮标设计的主要特点在于采用了数字自动增益控制技术,还用了模拟-频移键控混合的信号传输方式(DAGC/FSK/PM.),以保证得到大动态范围压缩,保持水声信号波形的线性输出.同时,由浮标内设FSK标准信号对传输信号作绝对校准,直接测得声压绝对级. 浮标具有多种遥测水下信号的功能,可测海洋环境噪声、舰船辐射噪声,水下连续声波以及爆炸声源等形式的信号,并兼作水声-无线电应答测距.经多次在内陆水库、北海、东海、南海海上测试,效果良好.证明是一种海上测量的适用且经济的设备.  相似文献
8.
The spatial coherences were investigated between the sound pressure and the three orthogonal components of the particle velocity in underwater ambient noise. Based on the ray theory, integral expression was derived for the spatial coherence matrix of the sound pressure and the particle velocity in a stratified ocean with dipole noise sources homogenously distributed on the surface. The integrand includes a multiplying factor of the vertical directivity of the noise intensity, and the layered ocean environment affects the spatial coherences via this directivity factor. For a shallow water environment and a semi-infinite homogenous medium, the coherence calculation results were given. It was showed that the sound speed profile and the sea bottom could not be neglected in determining the spatial coherences of the ambient noise vector field.  相似文献
9.
In order to solve the problem of DOA (Direction of Arrival) estimation of underwater distant wideband targets, a novel coherent signal-subspace method based on the cross spectral matrix of pressure and particle velocity using the Acoustic Vector Sensor Array (AVSA) is proposed in this paper. The proposed method is different from existing AVSA based DOA estimation methods in using particle velocity information of Acoustic Vector Sensor (AVS) as an independent array element. It is entirely based on the combined information processing of pressure and particle velocity, namely, the P-V cross spectrum, has better DOA estimation performance than existing methods in isotropic noise field. By theoretical analysis, both focusing principle and eigendecomposition theory based on the P-V cross spectral matrix are given. At the same time, the corresponding criteria for source number detection is also presented. Computer simulations with data from lake trials demonstrate that the proposed method is effective and obviously outperforms existing methods in resolution and accuracy in the case of low Signal-to-Noise Ratio (SNR).  相似文献
10.
Results of field studies of underwater dynamic noise energy flux directivity at two wind speeds, 6 m/s and 12 m/s, in the 400 Hz to 700 Hz frequency band in the deep open ocean are presented. The measurements were made by a freely drifting telemetric combined system at 500 m depth. Statistical characteristics of the horizontal and vertical dynamic noise energy flux directivity are considered as functions of wind speed and direction. Correlation between the horizontal dynamic noise energy flux direction and that of the wind was determined; a mechanism of the horizontal dynamic noise energy flux generation is related to the initial noise field scattering on ocean surface waves.  相似文献
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