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6th International Conference on Mechatronics and Intelligent Robotics, ICMIR 2022

作者： Hou, Hongying Li, Xiaoyuan Zhang, Liang Meng, Chunxia Dalian Scientific Test and Control Technology Institute Binhai street 16 DaLian116013 China Science and Technology on Underwater Test and Control Laboratory Binhai street 16 DaLian116013 China

ISBN: (纸本)9781510656635

The characteristic of far-field radiated noise of underwater vehicle is an important index to evaluate its stealth performance. Therefore, the level of radiated noise measurement technology has become a key factor affecting the ability of target acoustic recognition and stealth. This paper summarizes and analyzes the related progress of measurement technology of underwater vehicle radiated noise at home and abroad, including foreign PVLAMS, STAFAC measurement system, vector hydrophone measurement technology, civilian ship radiated noise test and standard, far-field estimation method based on actual measurement and model, etc. It provides a comprehensive reference conclusion for the research of radiated noise measurement technology and engineering practice. © 2022 SPIE.

关键词： Acoustic noise

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Acoustic Signature Analysis and Numerical Simulation on Radiated Noise of underwater Contra-rotating Propellers

Acoustic Signature Analysis and Numerical Simulation on Radi...

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2021 OES China Ocean Acoustics, COA 2021

作者： Ma, Fu-Qiang Liu, Yan-Sen Xie, Li-Xun Hu, Wen-Shuai Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (纸本)9781728181905

The noise of contra-rotating propellers contributes a major part to the underwater vehicle. The special noise properties often become an important basis for detecting and identifying targets. This paper establishes the numerical simulation and calculation approach on the radiated noise properties of contra-rotating propellers, which was set up based on the theory of acoustic analogy and the large eddy simulation approach, and then the numerical simulation results are verified. Taking the DTMB contra-rotating propellers which consist of DTMB3689 and DTMB3849 as an example, the numerical calculation of the hydrodynamic performance of the contra-rotating propellers is carried out based on the solving method of Reynolds stress turbulence model and the results agree well with the experimental results. The disk velocity distribution, blade pressure distribution and hydrodynamic wake distribution of the contra-rotating propellers are analyzed. Analyzing the acoustic signature of contra-rotating propellers shows that the low frequency line spectrum not only reflects the multiplicative frequency feature, but also the additive frequency feature, and the relationship between the radiated noise of the contra-rotating propellers and its inherent structure and its motion state is correlated. © 2021 IEEE.

关键词： Hydrodynamics

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Tuning interfacial charge transfer for efficient visible-light-driven photodegradation and simultaneous H_(2)evolution

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Journal of Materials science & technology 2024年第1期168卷 35-49页

作者： Zhiyang Li Yaogang Chen Yinghe Zhang Wei Ai Qian Lei Tingjun Yao Dan Zhong Wenjie Liu Wenbiao Jin Lei Yang State Key Laboratory of Urban Water Resource and Environment Shenzhen Key Laboratory of Organic Pollution Prevention and ControlSchool of Civil and Environmental EngineeringHarbin Institute of Technology ShenzhenShenzhen 518055China Key Laboratory of Northwest Water Resources Environment and EcologyMinistry of EducationSchool of Environmental and Municipal EngineeringXi’an University of Architecture and TechnologyXi’an 710055China CNAS Accredited Test Center Guangdong Engineering Technology Research Center of Air PurificationHealthlead Co.Ltd.Shenzhen 518055China School of Science Harbin Institute of Technology ShenzhenShenzhen 518055China

The edge-graphitized carbon nitride(C_(3)N_(4)-C g)was prepared by secondary pyrolysis to construct ZnO/C_(3)N_(4)-C g(ZCN)type-Ⅱheterojunction photocatalyst via a facile sonication dispersion method,which achieved∼7.04-fold and∼18.3-fold enhanced visible-light-driven photocatalytic performance for refrac-tory micropollutant removal and simultaneous hydrogen(H_(2))evolution respectively compared to con-ventional ZnO/g-C_(3)N_(4)Step-scheme *** apparent quantum efficiency of the ZCN_(0.4)het-erojunction reaches 0.92%(λ=420 nm).Such excellent performance stems from that the edge-graphene moieties stitched onto the interface of heterojunction extend light absorption to the full visible spec-trum,meanwhile,the built-in electric field generated during Fermi level alignment accompanying fa-vorable band-bending structure provides an effective pathway for the rapid migration of photoinduced electrons via the edge graphene channel to improve interfacial charge separation ***,the midgap states introduced in ZCN heterojunction could temporarily retain photoexcited electrons to effectively inhibit the in situ carrier recombination for improved photocatalytic H_(2)***,ZCN/peroxymonosulfate system exhibited excellent anti-interference performance against complex water bodies under visible illumination due to the synergistic effect between the co-existing anions and organic ***,the eco-friendly nature of the ZCN/peroxymonosulfate system showed no biotoxicity of reaction filtrate on cell proliferation after treatment,which avoided secondary ***-ering the outstanding performance in photocatalysis,the ZCN system exhibits broad potential for practical applications in water pollution control and green energy production.

关键词： ZnO C_(3)N_(4)-C g Heterojunction Photodegradation Hydrogen evolution

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Classification technology of underwater Targets in Decision Tree Based on Different Measurement Criteria

Classification Technology of Underwater Targets in Decision ...

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2021 IEEE International Conference on Signal Processing, Communications and Computing, ICSPCC 2021

作者： Sun, Yue Peng, Yuan Mu, Lin Zhang, Fengzhen Cao, Lin Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (纸本)9781665429184

In this paper, the selection of metrics for different branch attributes will affect the final division of different feature attributes. This article shares the principles of ID3 algorithm and CART algorithm using different information criteria, and use the princiciple of maximum information gain and the principle of minimum Gini index to generate decision trees. We use grid search and crass-validation methods to optimize CART algorithm, and finally we give the recognition accuracy of the feature data of the optimized algorithm. © 2021 IEEE.

关键词： Decision trees

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Research on jellyfish detection in cold source sea area of nuclear power plant based on high-resolution multibeam acoustic imaging

Research on jellyfish detection in cold source sea area of n...

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2021 International Conference on Computer Graphics, Artificial Intelligence, and Data Processing, ICCAID 2021

作者： Zhang, Jianfei Zhang, Xuegang Wu, Zhongpeng Science and Technology on Underwater Test and Control Laboratory NO. 14 Binhai Street Zhongshan District Liaoning Dalian116013 China

ISBN: (数字)9781510652170

ISBN: (纸本)9781510652163

The occurrence of cold source blockage in nuclear power plant not only affects the safety of power production, but also brings challenges to nuclear safety. Cold source reliability has become another important bottleneck restricting the development of nuclear power. Based on the consideration of improving the cold source safety of nuclear power plants, this paper studies the intrusion events of several typical marine organisms in nuclear power bases at home and abroad, analyzes the causes of the events, establishes a defense system in depth for marine organisms, identification, detection, early warning and hierarchical response, and uses underwater acoustic high-resolution multi beam detection method to detect marine organisms such as jellyfish and hairy shrimp, so as to obtain their echo characteristics, Analyze its distribution density in sensitive sea areas, and give effective early warning judgment. Among them, detection and early warning is the front-end disposal measure, which can provide emergency decision support for staff. Through the development and test of corresponding key equipment, the industrial safety risk is reduced, so as to improve the reliability of cold source. © 2022 SPIE.

关键词： Nuclear power plants

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Analysis of Irregular Characteristics of Reverberation Spectrum in Shallow Sea

Analysis of Irregular Characteristics of Reverberation Spect...

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2021 OES China Ocean Acoustics, COA 2021

作者： Wu, Jianglin Chen, Yunfei Jia, Bing Zhang, Yang Wang, Zhizhuan Wang, Jingying Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (纸本)9781728181905

Shallow sea reverberation is one of the main interferences in the active detection of underwater targets, and the working frequency of active sonar continues to expand to low frequencies, and the problem of reverberation interference is also receiving increasing attention. Focusing on the need to dig deeper into the frequency domain characteristics of shallow sea reverberation, this paper starts from the fluctuation characteristics of the low frequency reverberation spectrum in shallow seas, and uses spectral irregularity (SI) to characterize the spectrum fluctuations of the reverberation in shallow sea. First, based on the shallow sea reverberation point scattering model, the shallow sea reverberation is simulated. Combining with the definition of the spectrum irregularity value, the statistical results of the shallow sea reverberation spectrum irregularity value are studied, and the different pulse widths and different time periods of the multi-sample data are analyzed and compared. The results show that at the same transmitting frequency, when the pulse width of the transmitted signal increases, the SI value of the reverberation basically gradually decreases, and the SI value of the reverberation basically obeys the increase with the attenuation of the reverberation level. © 2021 IEEE.

关键词： Reverberation

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Jellyfish detection method based on high resolution multi beam acoustic imaging

Jellyfish detection method based on high resolution multi be...

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2021 International Conference on Computer Graphics, Artificial Intelligence, and Data Processing, ICCAID 2021

作者： Zhang, Jianfei Zhang, Xuegang Han, Jing Science and Technology on Underwater Test and Control Laboratory NO. 14 Binhai Street Zhongshan District Liaoning Dalian116013 China

ISBN: (数字)9781510652170

ISBN: (纸本)9781510652163

Aiming at the problem of jellyfish detection, a jellyfish detection method based on high-resolution multi beam acoustic imaging is proposed. The sea moon jellyfish detection experiments in real environment are carried out, and the individual echo characteristics of sea moon jellyfish are analyzed. The results show that the high-resolution multi beam acoustic method is effective to detect marine organisms at the outlet of nuclear power plant. © 2022 SPIE.

关键词： Marine biology

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6th International Conference on Communication, Image and Signal Processings, CCISP 2021

作者： Wang, Jingying Jia, Bing Zhang, Yang Wang, Rui Wu, Jianglin Wang, Zhizhuan Zhu, Yunfei Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (纸本)9781665432795

Target echo is the information source of active sonar, and the feature information of target echo highlight has important reference value for the detection and identification of active sonar system. According to the continuous acquisition of echo highlight at different azimuth angles, a bright spot sound image is formed in order to intuitively and effectively show the change rule of the target echo bright spot characteristics. In this paper, the target echo highlight-angle sound image simulation adopts the 1:20 scale Benchmark model, and use the image comparison method to compare the simulation results with the measured data. By comparing the results, it can be seen that under different signals and split angles, the two have a higher degree of similarity. And it is verified that the image contrast method in the research field of bright spot feature is effective. © 2021 IEEE

关键词： Sonar

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Research on the influence of object surface discontinuity on target acoustic scattering characteristics 6

Research on the influence of object surface discontinuity on...

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6th International Conference on Communication, Image and Signal Processings, CCISP 2021

作者： Wang, Rui Zhang, Yang Jia, Bing Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (纸本)9781665432795

This article focuses on the influence of the discontinuous surface of a combination of simple structures on the scattering characteristics of the *** three-dimensional vector model is used to simulate the constructed model group. Through numerical simulation, the scattering characteristics of the target discontinuous surface are analyzed on the relationship between the gap width and the wavelength, and the target characteristic changes caused by the target discontinuous surface are *** the same working conditions, for different incident angles, the trend of the echo energy at the gap changing with frequency is almost the *** different types of gap shapes, the target echo energy is weak when the gap boundary is smooth. © 2021 IEEE

关键词： Surface scattering

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Experimental study on waveguide invariant passive ranging based on buoy 6

Experimental study on waveguide invariant passive ranging ba...

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6th International Conference on Communication, Image and Signal Processings, CCISP 2021

作者： Wang, Zhizhuan Zhang, Mingwei Zhang, Yang Li, Guijuan Zhang, Xuegang Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (纸本)9781665432795

The important feature of ocean waveguides is that there is a stable and observable interference structure in the low-frequency sound *** interference structure can be described by only one scalar parameter beta, which is called waveguide invariant. It reflects the relationship between distance, frequency and interference fringe slope. Therefore, the motion parameter information of the target can be obtained by analyzing the LOFAR diagram of the radiated noise of a moving ship, as a kind of equipment which is easy to be placed in the marine environment, buoy has been widely used in the field of underwater acoustics. In this paper, using the buoy test data, the distance information of the passive target is obtained by the waveguide invariant method, which overcomes the defect that the traditional buoy ranging method needs multiple buoys. The distance estimation of the passive target is realized only by a single buoy, and the distance measurement error within the effective range is no more than 10%. © 2021 IEEE.

关键词： Buoys

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