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IEEE/OES China Ocean Acoustics (COA)

作者： Zhaohui Zhang Chen Hu Yuan Peng Fengzhen Zhang Lin Mu Science and Technology on Underwater Test and Control Laboratory China Science and Technology on Underwater Test and Control Laboratory Dalian China

underwater target recognition is very difficult because of the complexity of the ocean environment. The existing recognition technologies are mostly based on time domain, frequency domain, and time-frequency domain. Beam forming technology is a method of target recognition that has been researched and has developed rapidly in recent years. This paper applies beam forming and spatial spectrum analysis technology to an underwater echo signal in order to capture target echo and highlight spot and dimension features in the time-space domain. Image processing is used to extract the dimension and experimental data also verifies the feasibility of this method of beam forming.

关键词： Array signal processing Time-domain analysis Image resolution Signal resolution Image reconstruction

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Optimal Congestion control for Networks with Multiple Time Delays

Optimal Congestion Control for Networks with Multiple Time D...

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2017中国智能物联系统会议

作者： HAN Cunwu TONG Wei LI Mengqi PANG Zhonghua JIA Zhilei Beijing Key Laboratory of Fieldbus Technology and Automation North China University of TechnologyBe Tianjin Tianchuan Electrical Control Equipment Test Co. LTD.Tianjin 300300

This paper focuses on multiple time delays in congestion control for networks,which is seldom considered in the literature.A new mathematical state-space model for networks with different state and input time delays is established,a compensation algorithm for multiple time delays is *** optimal tracking algorithm is obtained and the optimal control law is derived by solving the matrix Riccati algebraic *** effectiveness of the proposed algorithm is verified through simulations.

关键词： Optimal control Network Congestion control Multiple Time Delays Optimal Tracking

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An acoustic beacon detection system based on wavelet packet transform

An acoustic beacon detection system based on wavelet packet ...

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IEEE/OES China Ocean Acoustics (COA)

作者： Xiaoyuan Li Jiasheng Qu Wei Ba Dalian Scientific Test and Control Technology Institute China The Key Laboratory for Underwater Scientific Test and Control Technology Dalian China

ISBN: (纸本)9781467399791

The underwater acoustic beacon is one of the most commonly used ocean acoustic instruments. It is installed in the underwater carrier and transmits signals according to certain rules. In this paper, we introduce an underwater acoustic beacon detection system based on a wavelet packet transform. The system is composed of a ruggedized computer, a directional receiving transducer, an angle sensor, a detection bracket et al. The ruggedized computer is equipped with signal conditioning module, signal acquisition and processing module, and single board computer. In the signal acquisition and processing module, the wavelet packet transform and the traditional weak signal extraction method are used to extract and identify the signal which transmits from the acoustic beacon. The detection results are shown in the form of audio and video. This system is easy to operate. Meanwhile, using hardware broadband filtering and DSP module narrowband filtering, the system can realize multi-frequency detection of underwater acoustic beacons. Experimental results show that, because of the use of the wavelet packet transform, the detection distance can be increased by 20 percent as compared to a system using the matched filtering method.

关键词： Transforms Computers underwater cables Universal Serial Bus Connectors Matched filters

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Isolation of Flavonoids from Leaves of Crataeguspinnatifida by HSCCC and prep-HPLC

Isolation of Flavonoids from Leaves of Crataeguspinnatifida ...

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第21届全国色谱学术报告会及仪器展览会

作者： Lei Wen Yunliang Lin RuiminLv Huijiao Yan Jinqian Yu Hengqiang Zhao Xiao Wang DaijieWang College of pharmacy Shandong University of traditional Chinese medicine Shandong Key Laboratory of TCM Quality Control Technology Shandong Analysis and Test CenterShandong Academy of Sciences

High-speed counter-current chromatography (HSCCC) has now been widely applied in the separation of various compounds, as a liquid-liquid partition chromatography, which [1] Generally speaking, HSCCC allows no solid support and the separation of compounds between the stationary and mobile phases constituted by two immiscible solvent systems, and possesses high

关键词： Leaves of Crataeguspinnatifida Flavonoids HSCCC and pre-HPLC Combination Blowout Strategy

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Enhanced Adaptive Equalization for MIMO underwater Acoustic Communications

Enhanced Adaptive Equalization for MIMO Underwater Acoustic ...

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Oceans (Conference)

作者： Jun Tao Liang An Yahong Rosa Zheng Key Laboratory of Underwater Acoustic Signal Processing of Ministry of Education Southeast University Nanjing China Ministry of Education of China Key Laboratory of System Control and Information Processing Shanghai China Missouri University of Science and Technology Rolla MO US

ISBN: (纸本)9781509064298;9780692946909

An enhanced normalized least mean squares (NLMS) adaptive equalization scheme is proposed for single-carrier underwater acoustic (UWA) communications. The enhancement is achieved via two techniques: the sparse adaptation (SA) technique and the data reuse (DR) technique. The SA technique speeds up the convergence and improves the performance of the adaptive equalization, by taking advantage of the inherent sparsity of the equalizer. It is implemented as the selective zero-attracting NLMS (SZA-NLMS) algorithm, developed by introducing a range of attraction for the existing zero-attracting NLMS (ZA-NLMS) algorithm. Compared with the ZA-NLMS, the SZA-NLMS incurs a lower complexity and achieves a better performance. The DR technique effectively prolongs the training length and significantly reduces the training overhead. Attributed to the DR technique, a high transmission efficiency is achieved even for a block transmission. The proposed adaptive equalization is verified by the real data collected in an atsea multiple-input multiple-output (MIMO) underwater acoustic communication trial. The experimental results show it considerably outperforms the standard NLMS adaptive equalization, especially with a low DR number.

关键词： Adaptive equalizers MIMO communication Training underwater acoustics Standards Phase locked loops

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Separation and purification of ten Lignans from Justicia procumbens *** high-speed counter-current chromatography in two-step elution mode

Separation and purification of ten Lignans from Justicia pro...

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第21届全国色谱学术报告会及仪器展览会

作者： Jiaojiao Jiang Tao Wang Ruixuan Zhao Zhenjia Zheng Yan Mu Yanling Geng Peng Yang Xiao Wang College of pharmacy Shandong University of traditional Chinese medicine Shandong Key Laboratory of TCM Quality Control Technology Shandong Analysis and Test CenterShandong Academy of Sciences

＜正＞As a new liquid-liquid chromatography technology, high-speed counter-current chromatography （HSCCC）used liquid as a carrier, which effectively avoiding the solid carrier adsorption, sample loss, ect[1-3]. Owing to HSCCC has the advantages of high recovery rate, excellent repeatability, large sample injection capacity, it has been applied increasingly in the preparation separation of bioactive ingredients in traditional Chinese

关键词： Justicia procumbens L. lignans high-speed countercurrent chromatography（HSCCC）

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Study on modulation spectrum feature extraction of ship radiated noise based on auditory model

Study on modulation spectrum feature extraction of ship radi...

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IEEE/OES China Ocean Acoustics (COA)

作者： Lin Mu Yuan Peng Mengran Qiu Xuemeng Yang Chen Hu Fengzhen Zhang Science and Technology on Underwater Test and Control Laboratory China

ISBN: (纸本)9781467399791

Under the noise interference environment, the auditory system of the human ear boasts strong robustness and reliability. Integrate the auditory model of the human ear into the ship radiated noise modulation spectrum extraction process can further improve the signal to noise ratio (SNR) and enhance the effect of the extracted modulation spectrum. This paper simulates the processing mechanism of the cochlear and the practical characteristics of ship radiated noise signals according to the integrated Gammatone auditory filter and the Meddis internal hair cell model, and it builds a Gamatone-Meddis auditory periphery model that is suitable for ship radiated noise signals. Then, the ship radiated noise signals are processed by the Gammatone-Meddis auditory model, the low-pass filtering (LPF), the Fast Fourier transform (FFT) and the multi-band integration in order to obtain an improved auditory spectrum extraction technique. The simulation results have verified that the Gammatone-Meddis model can extract modulation information well. After applying the method to a test of practical ship radiated noise signals, the author finds that the extraction method presented in this paper can obtain an obvious modulation spectrum at low SNR, and has a great advantage over the traditional modulation spectrum extraction methods.

关键词： Frequency modulation Time-frequency analysis Acoustics Character recognition Reliability Propulsion

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Separation and Purification of Acetophenones from Cynanchum bengei Decne Root Bark by Combination of Silica Gel and High-speed Counter-current Chromatography

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Medicinal Plant 2017年第2期8卷 8-11页

作者： Huaizhi LI Lingchuan XU Xiao WANG Qian LIU Jia LI Peng YANG Bingtian YANG School of Pharmacy Shandong University of Traditional Chinese Medicine Shandong Key Laboratory of TCM Quality Control Technology Shandong Analysis and Test Center Jinan Sanfeng Biological Pharmacy Co. Ltd.

[Objectives] To develop a method for separation and purification of acetophenones from Cynanchum bengei Decne root bark by combination of silica gel and high-speed counter-current chromatography( HSCCC). [Methods]The crude extract of Cynanchum bengei Decne root bark was separated by silica gel column chromatography,and parts A and B containing acetophenones were obtained. Then,parts A and B were separated by HSCCC with a two-phase solvent system composed of petroleum ether-ethyl acetate-methanol-water( 4∶ 6∶ 4. 5∶ 5. 5 and4∶ 6 ∶ 3 ∶ 7, V/V), respectively. [Results] From 260 mg of part A, four compounds with p-dihydroxybenzene 3. 9 mg(Ⅰ),4-hydroxyacetophenone 17. 1 mg( Ⅱ),2,5-di-hydroxyacetophenone 13. 3 mg(Ⅲ) and 2,4-dihydroxyaceto-phenone 21. 0 mg(Ⅳ) were obtained. And from 300 mg of part B,136 mg of Radix Cynanchi Bungei benzophenone(Ⅴ) was obtained. The purity of compounds determined by HPLC was 97. 0%,96. 6%,99. 2%,99. 7%,99. 5%,respectively. [Conclusions] The established method is simple and efficient. It can be used for separation of acetophenones from Cynanchum bengei Decne root bark and has better practical value,which could provide a reference basis for development and utilization of Cynanchum bengei Decne root bark.

关键词： Silica gel column chromatography High-speed counter-current chromatography(HSCCC) Acetophenones Cynanchum bengei Decne root bark

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Water tank experiments for laser backward-scattering properties of bubble cluster

Water tank experiments for laser backward-scattering propert...

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IEEE/OES China Ocean Acoustics (COA)

作者： Yuanyuan Guo Yunying Wang Fangyuan Jin Guijuan Li Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (纸本)9781467399791

In this paper, we focus on the backward-scattering properties of bubbles. Firstly, the distribution of scattering intensity of a single bubble with multiple particle sizes is studied (the theory of single bubble scattering is Mie Theory). Based on single bubble scattering, the Monte-Carlo method is used to simulate multiple scattering characteristics of bubble clusters with different densities under uniform distribution. Then a water tank experiment for laser backward-scattering properties of imitated bubble clusters is carried out. The results show that: the intensity of a backward scattered echo signal is exponential with increase of probe distance; the variability of backward scattered echo signal intensity is basically met by Marius's law and with the change of receiving polarization angle, the dynamic range of the backward scattered echo signals from water can be compressed for a particular polarization degree; and, the signal to noise ratio of the echo signal is greatly affected by the size of the receiving field angle. e.

关键词： Water Refractive index Streaming media Scattering Signal to noise ratio Backscatter

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Analysis of underwater object pose angle estimation method based on echo prediction

Analysis of underwater object pose angle estimation method b...

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IEEE/OES China Ocean Acoustics (COA)

作者： Yang Zhang Guijuan Li Zhenshan Wang Bing Jia Science and technology on underwater test and control laboratory Dalian China

The theory behind the forecast method of object pose angles has important engineering application value. In this paper, firstly, the planar elements method is used to predict near-field echoes of benchmark underwater objects, and build a characteristic sample database of object echoes; Secondly, by match-filtering measured object echoes with echo samples in the database, which are under various pose angles, parameters such as the correlation coefficient are obtained; Thirdly, a cost function is designed, the gained parameters are taken into the cost function, Finally, an estimated object pose angle is obtained. According to the time field echo structure, the pose angles are divided into several ranges: 0-40, 40-80, 80-110, 110-140, and 140-180degrees. The efficiency and robustness of the method are analyzed by statistic methodology in each pose angle range. A lake experiment was conducted, and the underwater object echo data were recorded. By comparing the estimated results with the real object pose angles, the estimation method is verified to be effective and robust. As a result of the good performance in robustness and fast computation speed, the method shows potential engineering applications.

关键词： Benchmark testing Robustness Estimation

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