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IEEE/OES China Ocean Acoustics (COA)

作者： Yunfei Chen Dapeng Yu Bing Jia Zhenshan Wang Jintao Yong Yanjie Wang School of Information and Communication Engineering Dalian University of Technology Dalian China Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (数字)9798350340297

ISBN: (纸本)9798350340303

The elastic scattering features of the underwater target scattering wave depend on the physical parameters of the target, such as the material and structure. Intuitively evaluating the influence of the elastic scattering wave on the characteristics of the whole scattering wave signal is difficult due to the coupling and superposition of the elastic scattering wave and the geometric scattering wave of the target. Based on the different modulation characteristics of broadband echo spectrum produced by target geometry scattering and elastic scattering wave, this paper characterizes and studies the modulation features of echo spectrum and tests the influence of physical parameters on the echo spectrum of underwater target using several simple cylindrical targets with different physical parameters. Moreover, the geometric scattering wave and the elastic scattering wave of the simple target echo are extracted using the fractional Fourier transform (FrF $T$ ) domain filtering method, and the influence of physical parameters on the echo spectrum is quantitatively analyzed.

关键词： Geometry Couplings Fourier transforms Filtering Oceans Scattering Modulation Feature extraction Acoustics Broadband communication

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A Dynamics Perspective of Defense-Intrusion Game 42

A Dynamics Perspective of Defense-Intrusion Game

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42nd Chinese control Conference, CCC 2023

作者： Wang, Keyang Zhao, Rui Wang, Yintao School of Marine Science and Technology Northwestern Polytechnical University Xi'an710072 China National Key Laboratory of Underwater Information and Control Xi'an710072 China The 705 Research Institute of China State Shipbuilding Corporation Limited Xi'an710077 China

ISBN: (纸本)9789887581543

Defense-intrusion games are fascinating in both nature and the artificial world. In these games, the purpose of defender is to protect the target from being attacked by the intruder, and if possible, capture the intruder. This article solves the defense-intrusion game with considering the bio-inspired model adopted by two agents-a defender and an intruder, and obtains the attack and interception strategies. The intruder usually need to avoid the defender, so we provide attack strategy based on setting the intruder's emergency maneuver distance, and compare it with the strategy based on artificial potential field method proposed in our previous work. For the defender, we design a radical interception strategy and a conservative interception strategy according to different circumstances. Numerical simulations are conducted to illustrate the effectiveness of the proposed strategies. The results are consistent with natural observations and disclose some natural laws in the defense-intrusion scenario. This paper will provide a reference for the research of intrusion prevention related to marine robots. © 2023 Technical Committee on control Theory, Chinese Association of Automation.

关键词： Network security

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Study on Fluctuation Characteristics of Acoustic Signals under Density Layered Fluid Disturbance

Study on Fluctuation Characteristics of Acoustic Signals und...

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IEEE/OES China Ocean Acoustics (COA)

作者： Jintao Yong Yunfei Chen Zhenshan Wang Bing Jia Rui Wang Shiqi Mo Science and Technology on Underwater Test and Control Laboratory Dalian China College of Underwater Acoustic Engineering Harbin Engineering University Harbin China College of Information and Communication Engineering Dalian University of Technology Dalian China

ISBN: (数字)9798350340297

ISBN: (纸本)9798350340303

This study investigates the fluctuation characteristics of acoustic signals in the presence of flow field perturbations within density-stratified fluids through laboratory simulation experiments. A density stratification tank was used to replicate the ocean's stratified environment. The SUBOFF scaled model was employed to mimic the underwater vehicle's navigation process in towing mode. controlled density stratification simulation experiments were conducted to explore the acoustic signal fluctuation characteristics within the wake flow field of the submerged model. Data on the undulation properties of acoustic signals that propagated through the wake flow field of the underwater vehicle were collected. The undulation characteristics of the acoustic signal at two towing speeds and various spatial positions were analyzed. In alignment with the typical marine environment characteristics, this study designed the stratification conditions, the scale of the scaled model, and the towing speed based on the Froude number (Fri) similarity criterion and the geometric similarity law. The analysis of the experimental results indicates that the fluctuating frequency of the acoustic signal amplitude diminishes over time as the wake dissipates post-target passage. Concurrently, the intensity of the high-frequency fluctuation component of the signal also decreases with the dissipation of the wake.

关键词： Time-frequency analysis Fluctuations Fluids Navigation Perturbation methods Oceans Attenuation Acoustics underwater vehicles

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A Data Association Method Based on Azimuth Inverse Cotangent Value

A Data Association Method Based on Azimuth Inverse Cotangent...

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International Youth Conference on Radio Electronics, Electrical and Power Engineering (REEPE)

作者： Nan Zou Muze Yin Guangpu Zhang Zhenqi Yang Pengbo Ma Dongyu Li National Key Laboratory of Underwater Acoustic Technology Harbin Engineering University Harbin China Key Laboratory of Marine Information Acquisition and Security (Harbin Engineering University) Ministry of Industry and Information Technology Harbin China College of Underwater Acoustic Engineering Harbin Engineering University Harbin China Science and Technology on Electronic Information Control Laboratory Chengdu China

ISBN: (数字)9798331531836

ISBN: (纸本)9798331531843

In this paper, we address the challenge of data association in scenarios involving multiple observers for underwater non-cooperative localization, where it is unclear how measurement data from different stations corresponds to the same target. We propose a novel data association method that leverages the inverse cotangent of azimuthal sequence features. The method first calculates the sequence of cotangent values measured by each station's bearing in a limited time. Linearly analyzes the sequence to obtain the slope, and finally realizes the data association according to the characteristic that the inverse cotangent value of the slope corresponds to the target's motion heading. The simulation results show that the proposed method has better association localization ability compared with the traditional method, overcomes the problem of the conventional method that the computational volume is too large when the number of observation stations and targets is large, and ensures the association correctness under a certain error.

关键词： Location awareness Power engineering Accuracy Azimuth Simulation Noise Observers Time measurement

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Test and Analysis of Compression Wave Sound Velocity Measurement in Ice by Direct Method

Test and Analysis of Compression Wave Sound Velocity Measure...

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2021 OES China Ocean Acoustics, COA 2021

作者： Jin, Bai Lianhui, Jia Chunxia, Meng Fengrui, Bai Science and Technology on Underwater Test and Control Laboratory Dalian China Dalian Neusoft University of Information Dalian China

ISBN: (纸本)9781728181905

The sound velocity in ice is of great significance to the acoustic propagation characteristics of ocean channels under ice cover and the acoustic characteristics of underwater targets. Freshwater ice has a uniform crystal structure under normal conditions. The freezing process of sea ice is more complicated compared to fresh water ice. The sea ice contains a lot of bubbles, brine, solid particles and other impurities. Due to the large difference in the structure and composition of ice in different states, it is very different from the common sound transmission media in the past. Therefore, in order to accurately describe the acoustic propagation characteristics of the ocean channel under the ice cover, it is necessary to measure the longitudinal sound velocity in the ice accurately. A direct method for measuring the speed of longitudinal waves in ice is studied in this paper. The propagation time of high-frequency pulses in the ice is used in this research to determine the speed of longitudinal waves. For the same piece of ice, the method of averaging multiple measurements was used to reduce the measurement error. Six tests were performed on typical ice with different structural characteristics. The six tests were the fresh water in Songhua Lake area of Jilin Province in 2019, the high mud content sea ice in the coastal area of Bohai Bay in 2020, the low mud content sea ice in Liaodong Bay area in 2021, the artificial quick-frozen sea ice and fresh water ice at -20°C, and the summer Arctic sea ice obtained in the eleventh Arctic scientific survey in 2020. The sound velocity of longitudinal waves in ice was measured at 12kHz, 25kHz, 50kHz, 75kHz, and 100kHz. The acoustic properties of ice are determined by its own state. The measurement results have certain fluctuations, because the test results were closely related to the sample test environment and test process. The measurement results of longitudinal wave sound velocity were described by the measurement mean value

关键词： underwater acoustics

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Low-radioactivity ultrasonic hydrophone used in positioning system for Jiangmen Underground Neutrino Observatory

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Nuclear science and Techniques 2022年第6期33卷 102-113页

作者： Duo Teng Jiang-Lai Liu Guo-Lei Zhu Yue Meng Yuan-yuan Zhang Tao Zhang Kai Luo Rui Li Jia-Qi Hui School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072China National Key Laboratory for Underwater Information Processing and Control Northwestern Polytechnical UniversityXi’an 710072China School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

To satisfy the accurate positioning requirement of the calibration source in the Jiangmen Underground Neutrino Observatory, a Tonpilz-type hydrophone with low radioactivity and high electroacoustics is *** radioactivity of the proposed hydrophone is strictly controlled by selecting pure raw materials, especially active piezoelectric ceramics. The electroacoustic performance of the hydrophone is improved by making structural optimization. High sensitivity and aimed directivity are achieved using 33-mode piezoelectric ceramic rings arranged in series and improvement in the radiating head of the Tonpilz hydrophone, respectively. All electroacoustic performances are studied through finite element *** simulations indicate that the electroacoustic performances of the hydrophones in linear alkylbenzene-based liquid scintillator can be approximately predicted according to the results in water because their differences caused by two types of acoustic media, water and liquid scintillator, are known. The tests show that the hydrophone prototype can achieve a maximum sensitivity of-209.3dB and a beamwidth of 132.2° at a frequency of 143 *** addition, eight hydrophones only contributed to a background radioactivity level of 26 ± 4 mHz in the neutrino analysis.

关键词： JUNO Liquid scintillator Tonpilz hydrophone Low radioactivity Sensitivity Directivity Finite element

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underwater Transducer Simulation Software Based on Finite Element Method

Underwater Transducer Simulation Software Based on Finite El...

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OCEANS

作者： Junwei Wang Zhong Luo Duo Teng Guolei Zhu School of Marine Science and Technology National Key Laboratory for Underwater Information Processing and Control Northwestern Polytechnical University Xi'an China

To remove the limitation of the special technical threshold in simulating or designing the transducer, an underwater transducer simulation software (UTS) is developed. UTS utilizes the interactive operation and the parametric design to achieve the automatic solution of the transducer. The finite element technology is the essences of UTS. In this study, the ANSYS processes are encapsulated by the ANSYS Parametric Design Language (APDL) macro and the JAVA language to achieve the electroacoustic simulations of a Tonpilz transducer. The results indicate that UTS is qualified in the transducer simulations.

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Comparison of Class I Flextensional Transducers with Concave Staves Machined by Different Materials

Comparison of Class I Flextensional Transducers with Concave...

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OCEANS

作者： Duo Teng Junwei Wang Zhong Luo Guolei Zhu School of Marine Science and Technology National Key Laboratory for Underwater Information Processing and Control Northwestern Polytechnical University Xi’an China

A Class I concave stave flextensional transducer is developed. Aiming at the electroacoustic performance of low frequency, high power, light weight and small size, the effect of the concave staves machined by the different materials on the flextensional transducer is studied. The finite element simulations illustrate the effect of the aluminium alloy, TC4 titanium alloy and 304 steel concave staves. The prototypes of the Class I concave stave flextensional transducer have been designed and fabricated. They have the size of Φ 96 × 160 mm, the weight of below 3 kg. Moreover, their resonance frequency is below 1.6 kHz and their source level is more than 194 dB. The tests verified the changes caused by the concave staves with different materials.

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A Method of Square Root Central Difference Kalman Filter for Target Motion Analysis 21st

A Method of Square Root Central Difference Kalman Filter for...

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21st Asia Simulation Conference, AsiaSim 2022

作者： Zheng, Yi Wang, Mingzhou Hu, Youfeng Yang, Yunchuan Yang, Xiangfeng Xi’an Precision Machinery Research Institute Xi’an710000 China Kunming Branch of Xi’an Precision Machinery Research Institute Kunming650118 China Science and Technology on Underwater Information and Control Laboratory Xi’an710000 China

ISBN: (纸本)9789811991943

The central differential Kalman filter (CDKF) and square root central differential Kalman filter (SR-CDKF) are widely used methods for addressing nonlinear problems in target motion analysis. However, for the bearings-only target motion analysis by single observer, sometimes the CDKF and the SR-CDKF experience the divergence problem or even filter interruption due to the observer’s mobility and system noise. To solve these problems, SR-CDKF is improved, and an adaptive singular value decomposition square root center difference Kalman filter (ASVDSR-CDKF) is proposed. The covariance square root update method based on the singular value decomposition method is deduced. The error discriminant statistics and adaptive factors are constructed. When the disturbance is too large, the adaptive factor is automatically adjusted and the square root updating form is selected. The simulation of bearings only target motion analysis is carried out under three different conditions, and the performance of CDKF, SR-CDKF, square root unscented Kalman filter (SR-UKF) and the proposed ASVDSR-CDKF method are compared. The simulation results demonstrate that the proposed method not only has high accuracy, but is also more stable than the other three methods. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Adaptive filtering

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Multivariate Multiscale Sample Entropy for Multi-Channel underwater Acoustic Signal Analysis

Multivariate Multiscale Sample Entropy for Multi-Channel Und...

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IEEE information technology, Networking, Electronic and Automation control Conference

作者： Jing Zhou Yaan Li Mingzhou Wang Lei Shi School of Marine Science and Technology Northwestern Polytechnical University Xi'an China National Key Laboratory of Underwater Information and Control Xi'an Precision Machinery Research Institute Xi'an China

ISBN: (数字)9798350370805

ISBN: (纸本)9798350370812

Multi-channel time series collected by arrays are prevalent in underwater acoustic signal processing and are crucial for uncovering the intrinsic characteristics of the observed system. This paper introduces the multivariate multiscale sample entropy (MMSE) to assess the complexity information in multi-channel underwater acoustic signals. Simulation analysis is employed to validate the effectiveness of the MMSE algorithm in extracting both within-channel and cross-channel information from multi-channel signals. Various types of simulated ship-radiated noise are generated to illustrate the MMSE algorithm's capability to differentiate between signals. Additionally, we employ MMSE to analyze various real-world signals, including ship-radiated noise, ambient noise, and interface reverberation. The MMSE results demonstrate its proficiency in differentiating various underwater acoustic signals compared to traditional frequency domain methods.

关键词： Heuristic algorithms Delay effects Noise Signal processing algorithms Feature extraction Entropy Classification algorithms Reverberation Data mining underwater acoustics

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