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2023 European Conference on Communication Systems, ECCS 2023

作者： Cui, Pei Jiang, Kaina Yue, Jin Wu, Yuanzhe Fu, Yibo Science and Technology on Underwater Test and Control Laboratory Dalian China Dalian Institute of Measurement and Control Technology Dalian China

ISBN: (纸本)9798350323344

The low-frequency electric field generated by various electromagnetic effects in the ocean overwrites the useful signal in amplitude and frequency, as a background distraction field for electric field detection. Effective electric field characteristic analysis and prediction methods are helpful to improve the environmental adaptability of the equipment and the ability of target detection. The deep learning method is used to mine the characteristics of underwater electric field in the marine environment to improve the prediction accuracy. In order to explore the relationship between seawater environmental parameters and electric field characteristics, parameters including measure time, seawater conductivity, water depth and wave height are used as independent variables, and the amplitude of the underwater electric field in the marine environment is used as the dependent variable. The relationship model between independent variables and dependent variables are established by deep neural network training to realize the prediction of underwater electric field characteristics in the marine environment. The results of 103 training samples and 2 test samples show that the method can effectively identify the test samples, and can be used for the mining and prediction of underwater electric field characteristics, as well as the detection and identification of weak electric field signals submerged in the marine environment. © 2023 IEEE.

关键词： Forecasting

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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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2024 OES China Ocean Acoustics, COA 2024

作者： Yong, Jintao Chen, Yunfei Wang, Zhenshan Jia, Bing Wang, Rui Mo, Shiqi 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: (纸本)9798350340297

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. © 2024 IEEE.

关键词： Wakes

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The measurement and analysis on dynamic evolution property for temperature field of trailing wake behind underwater vehicle 9

The measurement and analysis on dynamic evolution property f...

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9th Symposium on Novel Photoelectronic Detection technology and Applications

作者： Fangyuan, Jin Dongmei, Wang Yunying, Wang Yuanyuan, Guo Hui, Lin Lu, Zhang Science and Technology on Underwater Test and Control Laboratory No. 16 Binhai Street Zhongshan District Liao Ning Dalian China

ISBN: (纸本)9781510664432

The dynamic underwater temperature field and surface infrared characteristic of fluid field behind underwater vehicle in temperature stratification water was studied in this paper, using simulated water tank experiment and CFD (Computational Fluid Dynamics) study. In simulated water tank experiment study, the physical parameters of radio controlled scaled underwater vehicle model was fabricated with similarity ratio 1:100. Using the radio-controlled model, the movement of underwater vehicle in negative temperature gradient water was imitated, and the thermal evolution process of fluid field in water surface and under water was obtained by IR imager and underwater temperature sensors respectively. In theoretical study, the 3D N-S(Navier-Stocks) functions were calculated to verify the water tank results, and the initial condition and boundary condition were set using water tank experiment parameters. Both the simulated results and water tank experimental results could match with each other, and the results showed that: The evolutionary process of "cold trailing wake" in water surface could divided into four stages, which were called initial generation stage, stable development stage, diffusion stage and destruction stage;By reason of propeller's mixing effect, the hot water and the cold water exchanged heat unceasingly, which induced that the temperature near the surface was reduced, the temperature beneath the water was raised, and the temperature near the routes of model fluctuated with time. By comparing the theoretical value with the experimental value, the maximum simulation error of the theoretical model was 3.9dB. © 2023 SPIE.

关键词： Computational fluid dynamics

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Multi-UUV/USV Adaptive Cooperative Search Using Online State Information 1

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16th International Conference on Intelligent Robotics and Applications, ICIRA 2023

作者： Li, Wenjie Gao, Jian Chen, Yimin Cui, Pei Lv, Junjun Pan, Guang School of Marine Science and Technology Northwestern Polytechnical University Xi’an710072 China Science and Technology on Underwater Test and Control Laboratory Dalian116013 China

ISBN: (数字)9789819964987

ISBN: (纸本)9789819964970

Unmanned Surface Vessel (USV) and Unmanned underwater Vehicle (UUV) detect the same task plane while located in different planes, and have to avoid obstacles autonomously in cooperative search in unknown environments. This paper proposes an adaptive cooperative search method for a USV/UUV heterogeneous cross-domain swarm based on online state information. Considering the different planes of USV/UUV detection, we establish a USV/UUV detection model with a forward-looking sonar according to the cross-sectional view. In order to guarantee the safety of USV/UUV, an obstacle avoidance algorithm based on predictive guidance is designed. Finally, the task environment is rasterized to establish the state information structure of grids and USV/UUV. On this basis, USV/UUV adaptively plans the search path according to its own motion state. The state information of each grid is updated online until USV/UUV swarm completes the search task. Simulation results show that USV/UUV can accomplish cooperative search safely in an unknown environment. Compared with a UUV homogeneous swarm, the USV/UUV swarm shortens the search time and improves the cooperative search efficiency. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023.

关键词： Unmanned surface vehicles

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Breeze-activated wind speed sensor with ultra-low friction resistance for self-powered gale disaster warning

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science China(Technological sciences) 2023年第1期66卷 57-70页

作者： HE HuiCheng MU JiLiang MU JinBiao FENG ChengPeng ZHAO JuanHong WANG Yin ZHOU Hao ZHANG Le HE Jian CHOU XiuJian Science and Technology on Electronic Test and Measurement Laboratory North University of ChinaTaiyuan 030051China Sichuan Aerospace Fenghuo Servo Control Technology Corporation Chengdu 610000China

The early warning and monitoring of gale disasters are very important for the safety of people’s lives and properties. Triboelectric nanogenerators(TENGs) are popular for wind speed sensors due to their self-powered property. However, a TENG cannot easily work at low wind speeds due to the limitation of the high frictional resistance structure. In this paper, a TENG-based breezeactivated wind speed sensor(BAWS) with an ultra-low frictional resistance is proposed. The key drive unit of the BAWS is a Savonius-like vertical axis wind turbine, which is fabricated by arrayed airfoil profile blades with excellent flow field characteristics. Here a wind turbine plays dual roles in driving the electromagnetic generator below it to supply energy and lead the TENG above it to sense the wind force. Compared to a classical turbine with a wind cup, the designed turbine has a low resistance torque. The synergistic effect of the drive unit with low-resistance and triboelectric materials with low viscosity allows the BAWS to be activated even at a wind speed of 2.9 m/s. The sensitivities of the voltage frequency and current amplitude of the TENG are used to reflect the electrical property of the BAWS. The measured values are 0.291 Hz/(m·s-1) and 0.221 μA/(m·s-1),which reflects the good sensitivity of the BAWS. Moreover, the linearity of the BAWS reaches up to 0.991, which shows an accurate output for the wind speed. In addition, the device is equipped with a combined electromagnetic-solar unit as the sole power source to meet the sensor’s all-weather operation requirements. This work expands the application prospects of selfpowered sensing technology in the field of disaster warning.

关键词： gale disaster warning triboelectric nanogenerator wind speed sensor Savonius-like vertical axis wind turbine self-powered wireless sensing

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The polarization filtering line spectrum extraction algorithm of underwater target signal

The polarization filtering line spectrum extraction algorith...

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2022 International Conference on Information Processing in Ocean science and technology, ICIPOST 2022

作者： Han, Xue Wang, Yang College of Intelligent System Science and Engineering Shenyang University Liaoning Shenyang110044 China Science and Technology on Underwater Test and Control Laboratory DaLian China

In order to increase the performance of underwater target line spectrum extraction, an adaptive polarization filtering line spectrum extraction method is researched in the paper. By using of the polarization characteristics of underwater target signals, the polarization characteristics of underwater target line spectrum signal is analyzed via singular value decomposition (SVD) method in frequency domain. Firstly, the line spectrum signal is presented by the eigenimage corresponding to the maximum singular value to increase the signal-to-noise ratio (SNR) of the signal. Then the polarization parameters are extracted according to the polarization characteristics of the line spectrum signals. And the line spectrum signal is filtered by constructing the polarization filtering function. The simulation results show that the output SNR of the proposed method are larger than that of conventional FFT analysis method when the SNR of the signal is larger than -9dB, and the detection probability of the proposed method is 100% when the SNR of the signal is -1 dB, while the detection probability of the conventional FFT analysis method is 27.73%. It shows that the proposed method provides a new approach for underwater line spectrum signal extraction techniques. © Published under licence by IOP Publishing Ltd.

关键词： Signal to noise ratio

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Vertical Array Cable Jitter Noise Suppression Method using Frequency Vertical Wavenumber Spectral Filtering*

Vertical Array Cable Jitter Noise Suppression Method using F...

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IEEE/OES China Ocean Acoustics (COA)

作者： Peng Li Shuwei Che Yu Liu Xingchen Zhao Science and Technology on Underwater Test and Control Laboratory Dalian Scientific Test and Control Technology Institute Dalian China

ISBN: (数字)9798350340297

ISBN: (纸本)9798350340303

The proposed method suppresses low-frequency cable vibration noise in a vertical array acoustic observation system using the frequency vertical wavenumber spectrum. Initially, the frequency wavenumber spectrum is extracted from the data collected from the vertical array via vertical wavenumber-depth transformation. A frequency wavenumber domain filter is designed according to the sound wave speed in the cable, and cable interference is filtered out. The signal is restored via vertical wavenumber-depth inverse transformation. The simulation results show that under the simulation conditions described herein, low-frequency line spectra such as 30 and 60 Hz can achieve a signal-to-noise ratio improvement of $>1.2\text{dB}$ .

关键词： Vibrations Filtering Frequency-domain analysis Simulation Noise reduction Jitter Acoustics Arrays Signal to noise ratio testing

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Unsteady Narrowband Spectrum Enhancement Method of Ship Noise Using PSO and Stochastic Resonance Processing

Unsteady Narrowband Spectrum Enhancement Method of Ship Nois...

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IEEE/OES China Ocean Acoustics (COA)

作者： Wang Yang LIU Yan-sen WU Feng-ming Science and Technology on Underwater Test and Control Laboratory Dalian Scientific Test and Control Technology Institute Dalian China

ISBN: (数字)9798350340297

ISBN: (纸本)9798350340303

To enhance the unsteady narrowband spectrum of ship noise, an unsteady narrowband stochastic resonance processing method based on particle swarm optimization (PSO) was proposed. The method adopts a bistable stochastic resonance model and takes the mean signal-to-noise ratio in the narrowband bandwidth as the fitness function; it can perform adaptive optimal selection of system parameters matching the narrowband spectrum and background noise and can enhance the narrowband spectrum signal. According to the flow of the algorithm, the simulated unsteady narrowband spectrum and the measured ship noise data are processed and analyzed. The results show that this method can easily adapt to the characteristics of the narrowband ship spectrum and enhances a weak narrowband spectrum; it has broad research prospects and good application value.

关键词： Time-frequency analysis Stochastic resonance Oceans Sea measurements Object detection Marine vehicles Particle swarm optimization Time-varying systems Narrowband Signal to noise ratio

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Simulation of Vertical Highlight Distribution of underwater Objects Based on Virtual Extended Arrays *

Simulation of Vertical Highlight Distribution of Underwater ...

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IEEE/OES China Ocean Acoustics (COA)

作者： Yang Zhang Guijuan Li Rui Wang Wenhao Liu Jingying Wang Bing Jia Science and Technology on Underwater Test and Control Laboratory Dalian Scientific Test and Control Technology Institute Dalian China

ISBN: (数字)9798350340297

ISBN: (纸本)9798350340303

To study the vertical distribution characteristics of object echo in water, a simulation method based on a large-aperture virtual extended array is proposed. The proposed method adopts the near-field plate element method to predict the object echo waveform at the array end and takes advantage of the high resolution of the large aperture virtual extended array beam. Two-dimensional acoustic images of the object, such as the horizontal-vertical direction, horizontal distance, and range vertical, are obtained. The results show that the object echo highlights of the single-layer shell are obtained three parts of the boat: the hull, shell, and stern, and the vertical distribution characteristics reflect the vertical position relationship of the three parts. The formation mechanism of the echo highlights includes the smooth surface echo of a large area in the hull, hull, and other parts, and the angular wave at the joint of the hull and hull and the hull and stern.

关键词： Water Sea surface Image resolution Surface acoustic waves Boats Apertures Acoustic arrays Acoustics Acoustic beams

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Modeling of Ship Target Radiated Noise Spectrum Characteristics

Modeling of Ship Target Radiated Noise Spectrum Characterist...

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Computer technology and Information science (ISCTIS), International Symposium on

作者： Xuemeng Yang Science and Technology on Underwater Test and Control Laboratory Dalian China

This paper presents a comprehensive methodology for modeling ship target radiated noise spectrum characteristics, addressing the challenges of limited data availability. The proposed methodology includes data collection, preprocessing, feature extraction, and selection, along with the development of a noise spectrum model using advanced statistical techniques. Experimental evaluations using real-world ship noise data confirm the effectiveness of the proposed methodology in accurately capturing ship target radiated noise spectra. The findings have implications for underwater acoustic analysis and naval applications.

关键词：

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