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IEEE International Conference on Signal Processing, Communications and Computing (ICSPCC)

作者： Yue Sun Peng Yuan Guijuan Li Science and Technology on Underwater Test and Control Laboratory Dalian Liaoning Province China

ISBN: (数字)9781728172026

ISBN: (纸本)9781728172033

This paper addresses the problems of limited algorithm operation and low efficiency in the traditional standalone mode. Combined with the mainstream Spark distributed cloud computing platform, the decision tree algorithm is improved in parallel and transplanted to the cloud computing platform for data analysis and processing. First, introduce the operating mechanism of Spark and the principle of parallel computing, and then analyze the realization basis of parallelization of decision tree classification algorithm. Finally, through the deployed Spark cloud computing platform, the test results under different parameter combination conditions are given in recognition accuracy and running time, The overall classification and recognition effect and operating efficiency have been significantly improved.

关键词： Sparks Decision trees underwater acoustics Cloud computing Target recognition Parallel processing Impurities

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The Study on Inversion of Wave Equation Based on Adaptive Homotopic Regularization Method

The Study on Inversion of Wave Equation Based on Adaptive Ho...

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Communication, Image and Signal Processing (CCISP), International Conference on

作者： Jingying Wang GuoFeng Feng Yunfei Zhu Bing Jia Yunfei Chen Rui Wang Science and Technology on Underwater Test and Control Laboratory Dalian China Harbin Engineering University Harbin China

ISBN: (数字)9781728185897

ISBN: (纸本)9781728185903

The inversion of wave equation has a widespread applications in practice in the detection of buried targets. It faces non-linear and ill-posedness difficulties. Aiming to the ill- posedness and non-linear nature of the inverse problem of wave equation, the widely convergent homotopy method and regularization method are combined to constructing of minimum optimization equation. The linear relationship between homotopy parameters and regularization parameters is constructed in order to avoid the uncertainty of regularization parameters selected by experience. Then the adaptive homotopy regularization inversion method is formed by combining this technique with the Regularization- Gauss-Newton method. The results of numerical experiments show that the method is effectively deal with nonlinear and ill-posedness problem of buried target detection.

关键词： Propagation Mathematical model Inverse problems Optimization Numerical simulation Jacobian matrices Earthquakes

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Research on the Method of Judging the Transfer Path of Warship Transient Noise Excitation Source based on Information Similarity

Research on the Method of Judging the Transfer Path of Warsh...

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2019 IEEE International Conference on Power, Intelligent Computing and Systems, ICPICS 2019

作者： Li, Zhenyu Zhang, Bo Dai, Xuefeng Liu, Yanqiong First Laboratory Dalian Scientific Test and Control Technology Institute Dalian China

ISBN: (纸本)9781728137209

The warship is a very complicated system with many equipments and many excitation sources which can produce transient noise. Transient noise is mainly transmitted to the hull through elastic installation, pedestal and other supporting structures and non-supporting structures such as pipelines and cables. The vibration energy passes through the hull to the acoustic field and forms the radiated noise. Therefore, how to quickly and effectively find out the excitation source of ship transient noise has important military significance. It is difficult to distinguish the transmission channel of the excitation source of the transient noise because of the variety of ways of generating the transient noise and the interference of the mechanical noise. This makes the problem of excitation source discrimination become one of the important research directions of warship transient noise analysis. This paper aims to solve the problem of identifying the main transmission path of the excitation source. In this paper, through the study of principal component decomposition, instantaneous information similarity and so on, combined with the physical model of vibration transfer path, the main transfer path discrimination method suitable for the warship transient noise excitation source is established, and the validity of the method is verified by theoretical simulation. © 2019 IEEE.

关键词： Acoustic fields

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Algorithm Design and Software Implementation for Real-Time Detection of Echoes

Algorithm Design and Software Implementation for Real-Time D...

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2019 IEEE International Conference on Power, Intelligent Computing and Systems, ICPICS 2019

作者： Lin, Cao Min, Shi Science and Technology on Underwater Test and Control Laboratory Dalian116013 China Navy Academic of Armor Beijing China

ISBN: (纸本)9781728137209

In view of how to effectively detect a complete pulse period and the echo signal without triggering information and the fixed pulse cycle, this paper proposed a real-time detection algorithm of echo signal and developed a detection software of echo signal on the platform of Visual C++. First of all, the relative frequency domain energy detection algorithm was adopted to detect a pulse cycle through the adaptive threshold. Then, the echo signal was detected by the copy correlation algorithm. At last, the results were visualized in real time for the users. The experiment of the algorithm showed that the software can detect the complete pulse cycle and echo signal, and the performance of the system is quite stable. © 2019 IEEE.

关键词： Signal detection

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Effective prediction of organosilicon molecular structures and risks in aquatic environment with machine learning

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Science of the Total Environment 2025年 959卷 178320页

作者： Cao, Shengyu Tian, Youliang Zhao, Rusong Gu, Wen Tang, Song Xu, Lin Cai, Yaqi State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing100085 China School of Environment Hangzhou Institute for Advanced Study UCAS Hangzhou330106 China Guizhou Environmental Scientific Research and Design Institute Guizhou Guiyang550081 China Shandong Analysis and Test Center Key Laboratory for Applied Technology of Sophisticated Analytical Instruments of Shandong Province Jinan250014 China China CDC Key Laboratory of Environment and Population Health National Institute of Environmental Health Chinese Center for Disease Control and Prevention Beijing100021 China Center for Global Health School of Public Health Nanjing Medical University Jiangsu Nanjing211166 China

Until now, mass spectrometry databases lack molecular information of most organosilicon oligomers, and risk models needing accurate molecular descriptors are unavailable for these emerging contaminants with thousands of monomers. To address this issue, based on molecular/fragment ions and relative abundance from GC-Orbitrap-MS, this study developed appropriate classification (accuracies = 0.750–0.804) and regression (MSE = 0.008–0.014) models through neural network and support vector framework for organosilicon main/branch chain structures, which were subsequently used for speculating their persistent, bio-accumulative and toxic (PBT) potentials with neural networks (MSE = 0.002–0.017). By these methods, 116 oligomers [with 1–7 Si atoms, Si[sbnd]O (68.6 %) or C[sbnd]C (31.4 %) backbones, cyclic (14.7 %) or linear (85.3 %) structure, and six kinds of branch groups] were identified in waters from 21 Chinese cities, where hazard indices of total organosilicons were larger than 1 in 17 cities, with 5–43 oligomers first found in rivers showing persistent, bio-accumulative or toxic potential. Characteristic oligomers indicated dyeing, textile, and petrochemical industries making major contribution (13.1–34.8 %) to local organosilicon emission, and petrochemical industry was first found as ubiquitous source of nationwide organosilicon distribution. This study provided valuable methodology for risk assessment of organosilicons and also other chemicals lacking MS database. © 2024 Elsevier B.V.

关键词： Organosilicon

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A research on blind area of random layout units for localization 2

A research on blind area of random layout units for localiza...

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2nd International Conference on Mechanical, Electric and Industrial Engineering, MEIE 2019

作者： Wang, Zhizhuan Li, Ling Li, Guijuan Wang, Yang Science and Technology on Underwater Test and Control Laboratory Zhongshan Section Binhai Street 16 Dalian city116013 China

Acquisition distance information of the underwater target is very important to evaluate the target noise level, so it is necessary to do some research on the passive localization method for the underwater target. In this paper, the multi-hydrophone units model is used to passively achieve target localization information in the underwater environment;the accurate DOA estimation and ranging calculation method are presented. The localization blind area problem with different units models is discussed. The blind area problem caused by traditional passive localization model (three units) is solved by the method with four random units, which can locate the underwater unpredictable target in arbitrary direction. © 2019 IOP Publishing Ltd.

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Research on the real-time positioning method of vector buoys in deep sea

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Journal of Physics: Conference Series 2021年第1期1812卷

作者： Zhizhuan Wang Mingwei Zhang Ling Li Guijuan Li Yunfei Chen Xuegang Zhang Science and Technology on Underwater Test and Control Laboratory Dalian China

Buoys are generally difficult to anchor in Deep-sea environment, at the same, due to the influence of long-term in the ocean environment, the location relationship between each other buoys will change, which may cause the traditional predicted method of buoy system trapped in losing efficacy. This paper researched on the problem of the buoy baseline length vary positioning method applicability, on the basis of this study, focused on the theoretical analysis and simulation of applicability to different positioning method. Following this, a realtime positioning method based on vector buoys system in deep sea is presented. Covered the applicability shortage of traditional underwater acoustic passive positioning, used multiple vector buoys to locate the target jointly, and provide a theory basis for real-time positioning function of vector buoys in engineering. The simulation results show that this method is feasible and effective.

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Mechanism and influence of removing algae with chlorine dioxide treatment for ship ballast water

Mechanism and influence of removing algae with chlorine diox...

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作者： Linan Jia Dawen Jiao Yin Yue Xiaotao Shi Lin Sun Science and Technology on Underwater Test and Control Laboratory

This study aims at examining the performance of the ClO on treating ballast water of Dalian new port area foreign trade oil pool in the cases of different experimental parameters,and Cylindrospermopsis raciborskii（CR）,Gymnodinium catenatum（GC） and Gymnodinium ***（GCM） are used for this *** results shows that under certain test condition,the removal rates are in proportion to the dosage of ClO and reaction time,and inversely proportion to pH value,humic acid and ammonia nitrogen ***,on operating at the optimal dosage of ClO and parameters of experiment,this process is proven to be an effective technology to remove these three algae and organic compounds in ballast *** ballast water,the removal ability of ClO for these three algae is less sensitive to pH value,humic acid and ammonia nitrogen content than to ClO dosage and reaction *** GC,GCM and CR with ClO are attributed to the second order *** the performance of such process,could serve to develop management strategies that enable mitigating the impacts of harmful substance in ballast water and help improving and ensuring quality of ballast water.

关键词： GCM Mechanism and influence of removing algae with chlorine dioxide treatment for ship ballast water

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Experimental Study on Acoustic Attenuation of Bubble Wake

Experimental Study on Acoustic Attenuation of Bubble Wake

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作者： Jing Han Shuai Lv Zhongpeng Wu Mingwei Zhang Jin Bai Science and Technology on Underwater Test and Control Laboratory

When ship sails on the water surface, it will form a wake containing a large number of bubbles for different scales. The existence of bubbles will cause the attenuation of sound waves. In this paper, bubbles with different sizes are generated in the pool by using ceramic tube array. An experimental study on the acoustic attenuation characteristics of sound waves in bubbles was carried out for still water, small bubbles, medium-sized bubbles and large *** experimental research, it is found that the existence of bubbles makes the acoustic signal decay obviously. At different frequencies, bubbles decay more than 10dB relative to still water. Large bubbles have the strongest attenuation effect on acoustic signals, averaging over 20dB. The medium and small bubbles are similar to the attenuation of the acoustic signal. The acoustic signal intensity in static water and different scale bubbles is basically the same as the frequency.

关键词： Experimental Study on Acoustic Attenuation of Bubble Wake

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Envelope Phase Shift Feature Extraction of underwater Target Echo

Envelope Phase Shift Feature Extraction of Underwater Target...

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作者： Jintao Yong Yunfei Chen Yang Zhang Bing Jia Guijuan Li Science and Technology on Underwater Test and Control Laboratory

Aiming at the problem of target classification with different physical property parameters, the phase characteristics of echo envelope associated with different physical property parameters are studied, and the feature extraction method of the phase shift characteristics of the target echo envelope is established. The extraction method and the feature resolution performance of the phase shift characteristics of echo envelope are verified by the water-tank test of cylindrical targets with different materials and finite length. The experimental results of the underwater cylindrical target echo show that the feature of target echo envelope phase shift has significant difference with the change of target material, structure and radial scale. The phase shift feature of underwater target echo envelope has good performance for targets with different physical property parameters.

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