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Multiple extended target tracking algorithm based on Gaussian surface matrix

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Journal of Systems Engineering and Electronics 2016年第2期27卷 279-289页

作者： Jinlong yang Peng Li Zhihua Li le yang School of Internet of Things Engineering Jiangnan University

In this paper, we consider the problem of irregular shapes tracking for multiple extended targets by introducing the Gaussian surface matrix（GSM） into the framework of the random finite set（RFS） theory. The Gaussian surface function is constructed first by the measurements, and it is used to define the GSM via a mapping function. We then integrate the GSM with the probability hypothesis density（PHD） filter, the Bayesian recursion formulas of GSM-PHD are derived and the Gaussian mixture implementation is employed to obtain the closed-form solutions. Moreover, the estimated shapes are designed to guide the measurement set sub-partition, which can cope with the problem of the spatially close target tracking. Simulation results show that the proposed algorithm can effectively estimate irregular target shapes and exhibit good robustness in cross extended target tracking.

关键词： multiple extended target tracking irregular shape Gaussian surface matrix(GSM) probability hypothesis density(PHD)

Quantum Discord Behavior about Two-Qubit Heisenberg XYZ Model with Decoherence

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Chinese Physics letters 2014年第3期31卷 18-22页

作者： SONG le yang Guo-Hui School of Physics and Information Engineering Shanxi Normal University Linfen 041004

We investigate the properties of quantum discord dynamics of a two-qubit Heisenberg XYZ system which is influenced by the environmental decoherence under an external nonuniform magnetic field. It shows that the influence of the parameters on the system heavily rely on the selection of the initial states. One point shows that the environmental decoherence cannot entirely destroy the quantum correlation, and properly controlling the parameters can inhibit the decoherence. Moreover, it presents that the inhomogeneous magnetic field cannot affect the steady quantum discord （QD）, while the uniform magnetic field and the anisotropy coupling constant will change the steady QD. These investigations imply that one can obtain larger steady QD values by reasonably adjusting parameters on quantum correlation in solid state systems.

关键词： Magnetic fields

Wind tunnel simulation of wind loading on a solid structure of revolution

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Acta Mechanica Sinica 2010年第4期26卷 551-558页

作者： le-Tian yang Zhi-Fu Gu State Key Laboratory of Turbulence and Complex Systems and College of Engineering Peking University 100871 Beijing China

The wind tunnel simulations of wind loading on a solid structure of revolution with one smooth and five rough surfaces were conducted using wind tunnel tests. Timemean and fluctuating pressure distributions on the surface were obtained, and the relationships between the roughness Reynolds number and pressure distributions were analyzed and discussed. The results show that increasing the surface roughness can significantly affect the pressure distribution, and the roughness Reynolds numbers play an important role in the change of flow patterns. The three flow patterns of subcritical, critical and supercritical flows can be classified based on the changing patterns of both the mean and the fluctuating pressure distributions. The present study suggests that the wind tunnel results obtained in the supercritical pattern reflect more closely those of full-scale solid structure of revolution at the designed wind speed.

关键词： Wind tunnel simulation Roughness Reynolds number Pressure distribution Solid structure of revolution

Numerical analysis of a ventilated supercavity under periodic motion of the cavitator

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Journal of Hydrodynamics 2021年第6期33卷 1216-1229页

作者： Yun-hua Jiang Zhi-hui Zou Jia Li Yao Yao le-le yang School of Ocean Engineering and Technology Sun Yat-sen UniversityGuangzhou 510275China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519000China Department of Aerospace Engineering Harbin Engineering UniversityHarbin 150001China AVICJonhon Optronic Technology Co. Ltd.Luoyang 471003China

This paper presents a numerical simulation of the geometry and the pressure distribution of a ventilated supercavity at different cavitator amplitudes and periods of *** numerical method is validated by comparing with the results of a semi-empirical formula under specific *** is shown that the simulation can capture the boundary fluctuations of the ventilated supercavity and its internal pressure variations in a cavitator motion *** simulation results show that the supercavity boundary experiences wave-like deformations when the wavelength of the disturbance caused by the cavitator motion is comparable to the supercavity *** is also shown that the supercavity closure changes in form between a re-entrant jet and a twin vortex owing to the variations of the pressure difference between the outside and the inside of the supercavity near the closure *** maximum diameter of the ventilated supercavity exhibits periodic changes with a double peak in each cavitator motion cycle,caused by the corresponding changes of the difference between the internal and external *** the increase of the amplitude of motion of the cavitator,the supercavity boundary has enhanced wave-like undulations,with an increased maximum diameter,and with fluctuations in the cavitation *** the period of the cavitator motion increases,the wavelength of the disturbances caused by this motion becomes greater than the supercavity length,and so the wave-like undulations of the supercavity boundary and the maximum diameter of the supercavity gradually decrease,but the variations of the cavitation number ***,with the increase of the periods,the delay effects on the variations of the characteristics of the supercavity geometry caused by cavitator motion gradually decrease,and they practically vanish for large periods.

关键词： Ventilated supercavity geometrical and pressure characteristics cavitator motion

Electromagnetic interference modeling and suppression techniques in variable-frequency drive systems

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Frontiers of Mechanical Engineering 2018年第3期13卷 329-353页

作者： le yang Shuo WANG Jianghua FENG Electrical and Computer Engineering Department University of Florida Gainesville FL 32611 USA CRRC Zhuzhou Institute Co. Ltd. Zhuzhou 412001 China

Electromagnetic interference （EMI） causes electromechanical damage to the motors and degrades the reliability of variable-frequency drive （VFD） systems. Unlike fundamental frequency components in motor drive systems, high-frequency EMI noise, coupled with the parasitic parameters of the trough system, are difficult to analyze and reduce. In this article, EMI modeling techniques for different function units in a VFD system, including induction motors, motor bearings, and rectifierinverters, are reviewed and evaluated in terms of applied frequency range, model parameterization, and model accuracy. The EMI models for the motors are categorized based on modeling techniques and model topologies. Motor bearing and shaft models are also reviewed, and techniques that are used to eliminate bearing current are evaluated. Modeling techniques for conventional rectifierinverter systems are also summarized. EMI noise suppres- sion techniques, including passive filter, Wheatstone bridge balance, active filter, and optimized modulation, are reviewed and compared based on the VFD system models.

关键词： variable-frequency drive (VFD) electromagnetic interference (EMI) motor drive modeling EMI noise suppression

Water-soluble BODIPY and aza-BODIPY dyes： synthetic progress and applications

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Frontiers of Chemical Science and Engineering 2014年第4期8卷 405-417页

作者： Gang FANt le yang Zhijian CHEN School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

In recent years, boron-dipyrromethene （BOD- IPY） and boron-azadipyrromethene （aza-BODIPY） dyes have attracted considerable multidisciplinary attention due to their diverse applications. By introducing various hydrophilic groups, such as quaternary ammonium, sulfonate or oligo-ethyleneglycol moieties into the BOD- IPY core, the solubilities of these dyes in aqueous solution can be greatly improved while maintaining their high fluorescence quantum yields. Accordingly, applying these fluorescent dyes in aqueous systems to areas such as chemosensors, biomacromolecule labeling, bio-imaging and photodynamic therapy has been achieved. In this article, the recent progress on the synthesis, optical properties and application dyes and aza-BODIPY dyes of water-soluble BODIPY is reviewed.

关键词： boron-dipyrromethene boron-azadipyrro-methene synthetic progress applications

Effect of brain functional recovery decoction on expression of vascular endothelial growth factor and Ang-1 protein in a rat cerebral ischemia reperfusion model

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Journal of Traditional Chinese Medicine 2017年第1期37卷 76-79页

作者： yang Baocun Zhang Caixia yang le yang Jing Xiao Gaiqin Department of Traditional Chinese Medicine the first Affiliated Hospital of Xi'an Jiao Tong University School of Foreign Languages Shaanxi Normal University Medical School Xi'an Jiao Tong University

OBJECTIVE: To investigate the effect of brain functional recovery decoction(BFRD) on expression of vascular endothelial growth factor(VEGF) and angiopoietin-1(Ang-1) protein in rats with cerebral ischemia reperfusion injury, and to explore the mechanism of action of ***: Using the suture-occlusion method, a Wistar rat model of focal cerebral ischemia reperfusion was established. The rats were randomly divided into treatment group, model group, and sham operation group. The treatment group was administered BFRD. In situ hybridization was used to detect VEGF m RNA expression. Immunohistochemistry was used to observe expression of Ang-1 ***: VEGF mRNA expression was greater in the model group compared with the sham operation group(P < 0.05); Ang-1 protein expression was more obvious in the treatment group than the model group(P < 0.05).CONCLUSION: BFRD promoted VEGF m RNA and Ang-1 protein expression in the brains of rats with cerebral ischemia, suggesting increased angiogenesis.

关键词： Vascular endothelial growth factors Brain ischemia Angiopoietin-1 Stroke Brain functional recovery decoction

The Too-Big-to-Fail Premium in Tier-2 Capital Bonds and Additional Tier-1 Capital Bonds Primary Markets:Evidence from China

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China Finance and Economic Review 2024年第3期13卷 44-63页

作者： le yang Tsinghua University

This study examines the too-big-to-fail expectations in the primary market issuance spreads of commercial bank tier-2 capital bonds and additional tier-1 capital bonds in *** a sample of 574 issuances with total amount of 4.76 trillion RMB(749 billion USD),we conduct median regressions with the issuance spreads as the dependent *** coefficients of DSIB and GSIB are negative and statistically significant at 1%and 5%levels respectively in the full sample,and are negative and statistically significant at 1%level in the subsample after the guidance on asset management businesses was *** paribus,the issuance spreads of capital bonds of systemically important banks are 15.2 bps to 19.7 bps lower than those issued by other *** too-big-to-fail expectations and implicit guarantee of systemically important banks in the Chinese bond market,which narrow the primary market spreads of capital bonds issued by systemically important banks,may account for the *** address the potential endogeneity issues,we use 90%quantile and 95%quantile of sample bank consolidated assets as proxies of systemic importance,and use China Development Bank bond yields to calculate issuance spreads,and the results show that the conclusion is robust.

关键词： capital bonds issuance spread global systemically important bank toobig-to-fail

Secure and Robust Digital Watermarking： A Survey

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Journal of Electronic Science and Technology 2016年第4期14卷 343-354页

作者： Chun-Lin Song le yang Xin Wang Faculty of internet of Things Engineering Jiangnan University Wuxi 214122 China

A digital watermarking technique is a multi-scientific discipline which is developed rapidly in last several years for digital content protection, such as copyright protection, authentication protection, source tracing, etc. However, in realistic scenarios, the digital watermarking system faces significant secure issues, for example, the attackers want to remove, detect, or embed illegal watermark signals. Therefore, the aim of this contribution is to illustrate recent results of robust and secure watermarking to the signal processing community, and highlight both benefits and still open issues. Specifically, this paper is intended to introduce the concept of secure and robust digital watermarking system, and provide with problems and their countermeasures. First of all, the classic watermark model and cryptosystem will be reviewed and then, the concept of secure and robust digital watermarking system will be described. Next, the watermark attack will be classified and described. Finally, some countermeasures that can help to improve secure and robustness are considered.

关键词： Terms--Countermeasures digital watermarking system robust security watermark attacks.