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Analysis and application of the acoustic interfered field distortion for acoustic forward-scattering detection of underwater targets

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Chinese Journal of Acoustics 2022年第2期41卷 99-115页

作者： HE Chuanlin ZHENG Yi ma yuanliang Institute of Oceanographic Instrumentation Qilu University of Technology(Shandong Academy of Sciences)Qingdao 266100 School of Ocean Technology Sciences Qilu University of Technology(Shandong Academy of Sciences)Qingdao 266100 School of marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072

The signal-to-direct-blast ratio SDRF in acoustic forward-scattering detection can measure the relative magnitudes of the forward scattered wave and the direct-blast,but it does not consider the interference and superimposition effects between the two waves.These two waves inevitably interfere with one another and are difficult to distinguish,so it is difficult to directly apply SDRF in target detection and analysis.Based on SDRF and considering the interference between the forward scattered wave and the direct-blast,a new parameter called the acoustic interfered field distortion ΔFTL is developed,and the corresponding calculation formula is deduced.Compared with SDRF,ΔFTL can be obtained directly from data and has the advantage of not relying on prior information to a certain extent.The following is found according to this formula in combination with data from the Qiandao Lake scaled-target detection experiment.(1) Estimating the geometric expansion loss coefficient reveals that the acoustic wave propagates spherically,which is consistent with the simulation results of the ray model based on the measured hydrological parameters.(2) The relation between ΔFTL and the target crossing position is quantitatively confirmed,confirming the effectiveness of the ΔFTL formula.(3) A performance evaluation scheme independent of prior information is established for direct-blast suppression and then applied to an adaptive direct-blast suppression method.The influences of acoustic leakage and disturbances in the attitude angle of the target on the results can be ignored.These results show that ΔFTL can effectively replace SDR_(F),providing theoretical references for conducting performance evaluations on acoustic forward-scattering detection and direct-blast suppression.

关键词： distortion scattered underwater

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A study of the mixed layer of the South China Sea based on the multiple linear regression

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Acta Oceanologica Sinica 2012年第6期31卷 19-31页

作者： DUAN Rui YANG Kunde ma yuanliang HU Tao College of marine Northwestern Polytechnical UniversityXi'an 710072China Key Laboratory of Underwater Acoustic Environment Institute of AcousticsChinese Academy of SciencesBeijing 100190China

Multiple linear regression （MLR） method was applied to quantify the effects of the net heat flux （NHF）, the net freshwater flux （NFF） and the wind stress on the mixed layer depth （MLD） of the South China Sea （SCS） based on the simple ocean data assimilation （SODA） dataset. The spatio-temporal distributions of the MLD, the buoyancy flux （combining the NHF and the NFF） and the wind stress of the SCS were presented. Then using an oceanic vertical mixing model, the MLD after a certain time under the same initial conditions but various pairs of boundary conditions （the three factors） was simulated. Applying the MLR method to the results, regression equations which modeling the relationship between the simulated MLD and the three factors were calculated. The equations indicate that when the NHF was negative, it was the primary driver of the mixed layer deepening; and when the NHF was positive, the wind stress played a more important role than that of the NHF while the NFF had the least effect. When the NHF was positive, the relative quantitative effects of the wind stress, the NHF, and the NFF were about i0, 6 and 2. The above conclusions were applied to explaining the spatio-temporal distributions of the MLD in the SCS and thus proved to be valid.

关键词： mixed layer multiple linear regression South China Sea vertical mixing model

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Forward acoustic scattering by moving objects:Theory and experiment

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Chinese Science Bulletin 2012年第4期57卷 313-319页

作者： LEI Bo YANG KunDe ma yuanliang WANG Lu Institute of Acoustic Engineering Northwestern Polytechnical UniversityXi'an 710072China

The normal mode model for scattering in shallow water is employed to investigate the forward scattering with a target crossing the source-receiver axial line. An experiment was conducted in a littoral environment to analyze forward scattering by a slowly moving object. The theoretical and experimental results show that the sound field aberration takes minimum values if the object is located mid-point along the source-receiver line, whereas it attains its maximum if the object is close to the source or receiver. The total field is either enhanced or suppressed if the object crosses different Fresnel zones. In addition, the duration of shad- ow-induced aberration is dependent on the width of the first Fresnel zone, which is longest at the mid-point of the source-receiver line.

关键词：声散射实验物体移动菲涅尔区前向散射散射模型持续时间

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Tracking-positioning of sound speed profiles and moving acoustic source in shallow water

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Chinese Journal of Acoustics 2017年第4期36卷 439-453页

作者： GUO Xiaole YANG Kunde ma yuanliang Key Laboratory of Ocean Acoustics and Sensing(Northwestern Polytechnical University) Ministry of Industry and Information Technology School of marine Science and Technology Northwestern Polytechnical University

An ensemble Kalman filter（EnKF） approach is proposed to perform sequential tracking of water column sound speed profile（SSP） using a moving acoustic source. First,the SSPs are discretized in depth and range, and are expressed by the empirical orthogonal functions（EOFs）. Second, the acoustic source state information and the first three orders of EOF coefficients are expressed as the state variable, and the acoustic field information received by the vertical line array are the measured values. Successively, the state variables and measured values are used to establish the state-measure model. Last, the EnKF is utilized to track the state variables. The simulation results show that the root mean square error of SSP and the absolute error of source are all small, and thus the acoustic source tracking-positioning has high accuracy. Moreover, increasing the number of sample collection, the signal-to-noise ratio and the number of receiving elements can improve the tracking-positioning results. The method is verified using the experimental data of the East China Sea.

关键词： positioning Tracking shallow sequential ensemble collection verified utilized absolute interpolation

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Application of the direct blast adaptive suppression method to the forward scattered broadband signals

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Chinese Journal of Acoustics 2016年第4期35卷 348-358页

作者： HE Chuanlin YANG Kunde ma yuanliang LEI Bo Key Laboratory of Ocean Acoustics and Sensing(Northwestern Polytechnical University) Ministry of Industry and Information Technology School of marine Science and Technology Northwestern Polytechnical University

The basic principles of target detection by forward acoustic scattering are presented.A direct blast suppression approach based on adaptive filtering(DBS-AF) is proposed to suppress the direct blast.The DBS-AF technique is extended to the linear frequency modulation(LFM) signal,where the envelope of the signal is regarded as a 'general waveform' and imported into the adaptive filter.Application of the DBS-AF method to the data collected from a lake trial yields an output detection curve,in which the direct blast is mapped to the background while the acoustic field aberration is represented by the peak value fluctuation.The inhibitory effect in single hydrophone is approximately- 5 dB,and is then enhanced by exploiting the mean value removal approach as a preprocessing technique.The direct blast is further suppressed to a level of-10 dB by making full use of multichannel receptions.The main factors affecting the algorithm performance are as follows:the fluctuation degree of the receptions during the weighting vector training period and the power ratio of the forward scattered wave to the direct blast when the target is present.

关键词： Application of the direct blast adaptive suppression method to the forward scattered broadband signals

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SiO_(2)/g-C_(3)N_(4)复合材料的3D打印制备及对染料废水的处理性能

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工业水处理 2024年第3期44卷 64-73页

作者：赵文璞赵晓东季惠明马元良马生花沈铸睿天津大学材料科学与工程学院先进陶瓷与加工技术教育部重点实验室天津300350 青海民族大学物理与电子信息工程学院青海西宁810007 南开大学材料科学与工程学院天津300350

使用直写型3D打印的方式制备了高比表面积与多孔结构的SiO_(2)/g-C_(3)N_(4)复合气凝胶材料,并对材料的微观形貌、多孔结构进行了表征,测试了其对于模拟溶液中高浓度罗丹明B(RhB)的吸附及催化降解性能。研究结果表明,3D打印SiO_(2)块体... 详细信息

使用直写型3D打印的方式制备了高比表面积与多孔结构的SiO_(2)/g-C_(3)N_(4)复合气凝胶材料,并对材料的微观形貌、多孔结构进行了表征,测试了其对于模拟溶液中高浓度罗丹明B(RhB)的吸附及催化降解性能。研究结果表明,3D打印SiO_(2)块体气凝胶比表面积达482.1 m^(2)/g,具备孔隙体积为1.195 cm^(3)/g的纳米多孔结构,对RhB具有好的吸附性能。经g-C_(3)N_(4)修饰所得的SiO_(2)/g-C_(3)N_(4)复合气凝胶材料孔结构与比表面积变化不大,除仍保持较高的吸附性能外,在紫外光照下对RhB(100 mg/L)的去除率可达99%以上。经5次循环测试后SiO_(2)/g-C_(3)N_(4)复合气凝胶对RhB的去除率仍达92.98%,相比之下3D打印SiO_(2)气凝胶仅为55.75%。机理分析表明,复合材料中的g-C_(3)N_(4)可吸收光能并生成光生电子空穴对,其与H_(2)O和O_(2)作用产生氧化活性物质超氧自由基,最终均参与光催化氧化还原反应中对RhB大分子的催化氧化降解。3D打印结构具有的高比表面积实现了催化剂与RhB大分子较大的反应接触面积,提高了复合材料的光催化降解效率及循环稳定性。

关键词： 3D打印 SiO_(2)/g-C_(3)N_(4)复合气凝胶吸附降解

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6G:Ubiquitously Extending to the Vast Underwater World of the Oceans

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Engineering 2022年第1期8卷 12-17页

作者： yuanliang ma Qunfei Zhang Honglei Wang School of marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072China

1.Introduction There is a significant gap between atmospheric space and undersea space for wireless radio transmission.The interface between air and seawater is a barrier to prevent radio wave transmission across the boundary.This is because seawater is an electrically conducting medium,and radio waves suffer significant absorptive attenuation there.As a result,there is no internet,reliable mobile communication,high-quality video,and long-distance duplex wireless communication in the underwater world of oceans.It is pitiful since the oceans share 71%of the surface of our planet and are of great importance to our economy,ecology,and living environment.

关键词： communication wireless planet

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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 states.Statistics 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 Sea.Generated 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 dB.Whilst ambient noise was completely dominated by wind agitation,NLs were proportional to the cubic and quintic functions of WS and SWH,respectively.The 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 frequency.The 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 WS.The 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 Hz.Furthermore,standard deviation increased with frequency.The kurtosis was equal to 3 at>400 Hz approximately.The 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

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A approach for generating high precision digitaltime-delay with low computational load

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Chinese Journal of Acoustics 1995年第1期14卷 27-33页

作者： ma yuanliang ZHAO Junwei and ZHANG Yanwu (College of marine Engineering Northwestern Polytechnical University. Xi’an Shaanxi 710072)

In this paper a novel method to generate high-precision and continuously adjustable digital time-delay by utilizing the linear phase of a FIR filter is presented. The generated time-delay can be continuously changed by adjusting the filter weights. The time-delay is pre cise and valid for wide-band, while the computational load is low. The proposed approach can find applications in wide-band digital beamforming, adaptive delay estimation, temporal analy sis of reflected waveform, etc.. In the paper, the basic principle, design steps and simulation re sults are given. Also shown are some typical practical applications.

关键词： Continuously adjustable High-precision FIR digital filter Novel approach Low computational load

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Multi-injection Synthesis of CdSe Nanocrystals by Solution Process with Glycerol-Ethylene Glycol

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Journal of the Chinese Ceramic Society 2014年第2期 99-105页

作者： ma yuanliang ZHENG Xuerong LI Haiqin WANG Tao JI Huiming College of Physics and Electronic Information Engineering Qinghai University for Nationalities Key Laboratory of Advanced Ceramics and machining Technology of Ministry of Education School of Materials Science and EngineeringTianjin University

Wurtzite CdSe nanocrystals were synthesized by a multi-injection solution chemical process with glycerol-ethylene glycol based solvent,sodium selenite and cadmium nitrate-tetrahydrate as precursors,ammonia as a chelating agent and hydrazine hydrate as a reducing agent.The crystal phase,morphologies and optical absorption of the as-prepared CdSe nanocrystals were characterized by X-ray diffraction,scanning electron microscopy,transmission electron microscopy and UV-Vis analysis,respectively.The relation between the light absorbance and reaction time for three reaction solutions with different hot injection styles was analyzed via the UV-Vis measurement at a wavelength of480 nm.The results show that the injection style in the multi-injection process has an effect on the nucleation and growth,crystal size,dispersing stability and optical band-gap energy of the nanocrystals.The mild injection style results in the formation of uniform and well-dispersive nanocrystals.

关键词： CdSe nanocrystals multi-injection synthesis polyol based solution injection styles

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