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INFLUENCE OF OCEAN INTERNAL WAVE ON PROPAGATION OF UNDER-WATER RADIATION NOISE

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Journal of Hydrodynamics 2004年第1期16卷 61-66页

作者： YEChun-sheng SHENGuo-guang SchoolofCivilEngineering TianjinUniversityTianjin300072China

The underwater acoustic field influenced by a selected ocean internal wavewas computed using the Parabolic Equation (PE) method and split-step difference algorithm in thispaper. Acoustic field is formed by sound source with different frequency covering the range ofradiation noise of ships and submarines. Owing to the adoption of complex variables, sparse matrix,Gaussian source and analysis on the grid size, numerical results are achieved smoothly. The resultsshow that internal wave''s influence on underwater sound can''t be neglected, especially for highersound frequency. So it'' s necessary to take internal wave into account in identifying radiationnoise of ships and submarines, namely for sound intensity, transmission loss and spectra shape.

关键词： ocean internal wave underwater acoustics radiation noise parabolicequation (PE) method

Reliability indexes for multi-AUV cooperative systems

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Journal of Systems Engineering and Electronics 2017年第1期28卷 179-186页

作者： Qingwei Liang Tianyuan Sun Dongdong Wang College of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072China The 32th Research Institute of China Electronic Technology Group Corporation Shanghai 200233China

With the development of multi-autonomous underwater vehicle (AUV) cooperative systems, the evaluation of their reliability is becoming more and more important. Aimed at the characteristics of the system, three reliability indexes-standard entropy of rank distribution, all-terminal reliability and standard natural connectivity are determined in this paper. Topology structure and underwater acoustic communication are considered. The calculation methods of the three reliability indexes are proposed, and the characteristics of these indexes are analyzed. The reliability indexes of two multi-AUV cooperative systems are obtained as examples. Results show that these three indexes reflect different aspects of reliability for multi-AUV cooperative systems. This paper provides some methods to evaluate the reliability of multi-AUV cooperative systems, which is of practical value. © 1990-2011 Beijing Institute of Aerospace Information.

关键词： Cooperative communication Offshore pipelines Reliability underwater acoustics

Effect of Source＇s Height on Air-to-Water Sound Transmission with a Small-Scale Rough Sea Surface

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Chinese Physics Letters 2014年第9期31卷 86-90页

作者：张灵珊彭朝晖 State Key Laboratory of acoustics Institute of Acoustics Chinese Academy of Sciences Beijing 100190 University of Chinese Academy of Science Beijing 100190

A self-consistent perturbation approach is presented/or analyzing the effect of theairborne source＇s height on the air-to-water sound transmission in shallow water with a randomly rough sea surface. It is shown in early researches that, in shallow water with a smooth sea surface, the airborne source＇s height mostly affects the phase of the sound field and barely influences the amplitude. However, in shallow water with a rough sea surface, few researches about such a problem have been published. In this work, the sound fields in shallow water with a randomly rough sea surface induced by an airborne source at different heights are calculated by a seff-consistent perturbation approach. The numerical simulation results show that the fluctuation of the scattered field decreases as the source＇s height increases, in contrast, the averaged energy of the total field is hardly influenced by the source＇s height in the statistical sense.

关键词： PERTURBATION (Mathematics) RESEARCH TRANSMISSION of sound -- Research underwater acoustics WATER depth SCATTERING (Physics)

Hydrodynamic Sensing Based on Surface-Modified Flexible Nanocomposite Film

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Chinese Physics Letters 2015年第11期32卷 76-79页

作者：束逸田禾王哲赵海明米文天李宇星曹慧文任天令 Institute of Microelectronics Tsinghua University

A highly sensitive sensor with piezoresistive nanocomposite material assembled in a flexible composite film is designed and tested for hydrodynamic sensing. Within the device, two nanocomposite films with micrometer scale modified small bumps on the surface are arranged together face-to-face by the interlocking mechanism. These structures are verified to have full-scale piezoresistive high sensitivities which are very appropriate for underwater sensing. Obvious output signals can be observed from the device subjected to the hydroacoustic dipole （vibrating sphere） with exciting frequency from 10 Hz to 40 Hz. A spectral peak can be seen in the Fourier analysis of the output signal at the corresponding frequency.

关键词： HYDRODYNAMICS NANOCOMPOSITE materials PIEZORESISTIVE devices underwater acoustics CARBON nanotubes

Low-Frequency Hydroacoustic Experiments on the Shelf Using the Data of Geoacoustic Sediment Model

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Chinese Physics Letters 2014年第12期31卷 66-69页

作者： SAMCHENKO A. N. KOSHELEVA A.V. SHVYREV A. N. PIVOVAROV A. A. Il'icheve's Pacific Oceanological Institute (POI) FEB RAS Vladivostok 690041 Russia

Acoustic and seismoacoustic methods have become the most perspective and intensely developed meth- ods in the research of dynamic processes and inho- mogeneities in shallow water. Seismoacoustic moni- toring allows one to draw conclusions about the pres- ence of different inhomogeneities in the water environ- ment and to identify various dynamic processes in the oceanic shelf zone. Studies of the propagation of hy- droacoustic signals of different frequencies and config- urations are widely discussed in scientific publications in Russia, China and the United States Solutions to inversion problems in acoustics, the con- struction of geoacoustic models and research of low- frequency acoustic signals with respect to the absorb- ing bottom are without any doubt at the forefront of underwater acoustics.

关键词： underwater acoustics SEDIMENTS (Geology) ACOUSTIC signal processing WATER CONTINENTAL shelf MATHEMATICAL models

Frequency Dependence of Transverse Correlation Coefficient in the Yellow Sea

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Chinese Physics Letters 2010年第8期27卷 99-101页

作者：张燕君张仁和李风华 National Laboratory of acoustics Institute of Acoustics Chinese Academy of Sciences Beijing 100190 Graduate University of Chinese Academy of Sciences Beijing 100049

Horizontal correlation is one of the most important characteristic parameters in ocean acoustics. In a shallow water acoustic experiment, we observed that the transverse correlation coemcient is an oscillation function of frequency. A model based on adiabatic normal mode theory in a random inhomogeneous waveguide which is statistically isotropic in a horizontal plane is developed. The theory indicates that the oscillation of the transverse correlation coefficient is mainly due to the normal mode interference.

关键词： CORRELATION (Statistics) WAVEGUIDES OCEAN tomography underwater acoustics FREQUENCIES of oscillating systems INTERFERENCE (Aerodynamics)

Statistics of underwater ambient noise at high sea states arisen from typhoon out zones in the Philippine Sea and South China Sea

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Acta Oceanologica Sinica 2022年第7期41卷 153-165页

作者： Qiulong Yang Kunde Yang Shunli Duan Yuanliang Ma School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an710072China Key Laboratory of Ocean acoustics and Sensing Ministry of Industry and Information TechnologyXi’an710072China Key Laboratory of Marine Environmental Information Technology Ministry of Natural ResourcesTianjin300171China

Oceanic noise is the background interference in sonar performance prediction and evaluation at high sea *** of underwater ambient noise during Typhoons Soulik and Nida were analyzed on the basis of experimental measurements conducted in a deep area of the Philippine Sea and the South China *** linear regression,frequency correlation matrix(FCM),Burr distribution and Gumbel distribution were described for the analysis of correlation with environmental parameters including wind speed(WS),significant wave height(SWH),and the inter-frequency relationship and probability density function of noise levels(NLs).When the typhoons were quite close to the receivers,the increment of NLs exceeded 10 *** ambient noise was completely dominated by wind agitation,NLs were proportional to the cubic and quintic functions of WS and SWH,*** fitted results between NLs and oceanic parameters were different for“before typhoon”and“after typhoon”.The fitted slopes of linear regression showed a linear relationship with the logarithm of *** average observed typhoon-generated NLs were 5 dB lower than the Wenz curve at the same wind force due to the insufficiently developed sea state or the delay between NLs and *** cross-correlation coefficient of FCM,which can be utilized in the identification of noise sources in different bands,exceeded 0.8 at frequencies higher than 250 ***,standard deviation increased with *** kurtosis was equal to 3 at>400 Hz *** characteristics of NLs showed good agreement with the results of FCM.

关键词： statistics underwater acoustics cruise-measured ambient noise typhoon Philippine Sea South China Sea deep ocean

Modeling and volume rendering approach of underwater three-dimensional acoustic energy field

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International Journal of Modeling, Simulation, and Scientific Computing 2016年第3期7卷 171-180页

作者： Yanyang Zeng Panpan Jia College of Computer Science and Technology Henan Polytechnic University 2001 Century Avenue Jiaozuo 454000HenanP.R.China

The underwater acoustics is primary and most effective method for underwater object detection and the complex underwater acoustics battlefield environment can be visually described by the three-dimensional(3D)energy *** solving the 3D propagation models,the traditional underwater acoustics volume data can be obtained,but it is large amount of *** this paper,a novel modeling approach,which transforms two-dimensional(2D)wave equation into 2D space and optimizes energy loss propagation model,is *** this way,the information for the obtained volume data will not be lost too *** the same time,it can meet the requirements of data processing for the real-time *** the process of volume rendering,3D texture mapping methods is *** experimental results are evaluated on data size and frame rate,showing that our approach outperforms other approaches and the approach can achieve better results in real time and visual effects.

关键词： underwater three-dimensional acoustic energy field underwater acoustics three-dimensional texture mapping volume rendering volume data

underwater Terrain-Aided Navigation Based on Multibeam Bathymetric Sonar Images

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Journal of Marine Science and Application 2015年第4期14卷 425-433页

作者： Ziqi Song Hongyu Bian Adam Zielinski Acoustic Science and Technology Laboratory Harbin Engineering University Harbin 150001 China College of underwaterAcousticEngineering Harbin Engineering University Harbin 150001 China Department of Electrical and Computer Engineering University of Vietoria Victoria V8 W 2Y2 Canada

underwater terrain-aided navigation is used to complement the traditional inertial navigation employed by autonomous underwater vehicles during lengthy missions. It can provide fixed estimations by matching real-time depth data with a digital terrain map, This study presents the concept of using image processing techniques in the underwater terrain matching process. A traditional gray-scale histogram of an image is enriched by incorporation with spatial information in pixels. Edge comer pixels are then defined and used to construct an edge comer histogram, which employs as a template to scan the digital terrain map and estimate the fixes of the vehicle by searching the correlation peak. Simulations are performed to investigate the robustness of the proposed method, particularly in relation to its sensitivity to background noise, the scale of real-time images, and the travel direction of the vehicle. At an image resolution of 1 m2/pixel, the accuracy of localization is more than 10 meters.

关键词： underwater acoustics terrain-aided navigation sonar images histogram autonomous underwater vehicle multibeam bathymetric sonar