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Multicomponent Chirp Signal Detection Using Fractional Fourier Analysis

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Journal of Systems Engineering and Electronics 1999年第3期10卷 57-63页

作者： Dong, Yongqiang tao, ran zhou, siyong wang, yue Beijing Inst of Technology Beijing China

The aim of this paper is to propose a novel technique for the detection of multicomponent chirp signal and the parameter estimation based on fractional Fourier transform (FRFT). The relationship between the FRFT and the Wigner-Ville distribution (WVD) is investigated and the performance of the new approach is analyzed both in the computation complexity and the resolution in the fractional Fourier domain.

关键词： Fourier transforms Computational complexity Image quality Parameter estimation

Serial Failure Diagnosis of a Transmission Line Protection Relaying System by Petri Nets

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Journal of Systems Engineering and Electronics 2001年第1期12卷 59-64页

作者： Zhang Zhiming wang yue tao ran &zhou siyong Dept. of Electronics Engineering, Beijing Institute of Technology, 100081, P. R. China Dept. of Electronics Engineering Beijing Institute of Technology Dept.of Electronics Engineering Beijing Institute of Technology

With the development of large-scale complicated modern power systems, the requirement for the associated protection scheme tends to be more stringent and its combination more complex. However, it is very difficult to figure out the factors of failure of such systems. This paper proposes a Petri net model of a transmission line protection relaying system, including three types of relays as well as an automatic reclosing device, and shows how to diagnose serial failure of the system by analyzing invariant sets of the model. Furthermore, it gives four basic types of failure sequences and its execution is much more intuitive and effective than the traditional method.

关键词： Electric fault location Electric power system protection Electric relays Failure analysis Mathematical models Petri nets Relay protection

ANALYZING OF MULTICOMPONENT UNDERSAMPLED SIGNALS BY HAF

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Journal of Electronics(China) 2001年第2期18卷 121-126页

作者： tao ran shan tao zhou siyong wang yue (Department of Electronic Engineering, Beijing Institute of Technology, Beijing 100081) Department of Electronic Engineering Beijing Institute of Technology Beijing

The phenomenon of frequency ambiguity may appear in radar or communication systems. S. Barbarossa(1991) had unwrapped the frequency ambiguity of single component undersampled signals by Wigner-Ville distribution(WVD). But there has no any effective algorithm to analyze multicomponent undersampled signals by now. A new algorithm to analyze multicomponent undersampled signals by high-order ambiguity function (HAF) is proposed hera HAF analyzes polynomial phase signals by the method of phase rank reduction, its advantage is that it does not have boundary effect and is not sensitive to the cross-items of multicomponent *** simulation results prove the effectiveness of HAF algorithm.

关键词： Undersampled signal Frequency estimation HAF

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欠采样信号频率估计

兵工学报 2000年第2期21卷 174-176页

作者：陶然单涛周思永王越北京理工大学电子工程系北京100081

在合成孔径雷达 ( SAR)对运动目标成像和 MTI、MTD雷达探测动目标时 ,都有可能出现频率模糊现象 ,到目前为止 ,还没有快速、有效地解此频率模糊的算法。本文提出了高阶模糊函数 ( HAF)分析欠采样信号的新方法。HAF算法从相位降阶角度出... 详细信息

在合成孔径雷达 ( SAR)对运动目标成像和 MTI、MTD雷达探测动目标时 ,都有可能出现频率模糊现象 ,到目前为止 ,还没有快速、有效地解此频率模糊的算法。本文提出了高阶模糊函数 ( HAF)分析欠采样信号的新方法。HAF算法从相位降阶角度出发分析连续调频信号 ,与时频分析法相比 ,大大降低了计算量 ,且放松了边界条件要求。

关键词：欠采样频率估计时频分布即时频率 HAF

THE APPLICATION RESEARCH OF VIDEO SERVER SYSTEM FOR VIDEO ON DEMAND

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Journal of Electronics(China) 2006年第2期23卷 295-297页

作者： Zhang Yinghui tao ran wang yue zhou siyong Department of Electronic Engineering Beijing Institute of Technology Beijing 100081 China

A comprehensive research on key issues of the large-scale video server system for Video On Demand (VOD) client/server system is conducted based mainly on real time (rt)/non-real time (nrt) Variable Bit Rate or Constant Bit Rate (VBR/CBR) MPEG-2 MP@ML Signal Program Transport Stream (SPTS) for movies, and general architecture for storage, control, caching subsystems from Loosely Coupled Computer (LCC), Symmetric Multiple Processing (SMP), and Massively Parallel Processing (MPP) video server is conceptualized. Meanwhile, Redundant Array of Inexpensive Disks (RAID) storage system are presented and the centralized FCP/SAN huge storage technology is introduced in terms of its scalability, throughput, and connectivity performances.

关键词： Video on demand Video server Variable Bit Rate (VBR) Constant Bit Rate (CBR) Client/server

THE MULTIMEDIA SET-TOP-BOX BASED ON PC PLATFORM

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Journal of Electronics(China) 2005年第5期22卷 546-549页

作者： Zhang Yinghui tao ran wang yue zhou siyong Department of Electronic Engineering Beijing Institute of Technology Beijing 100081 China

A comprehensive research on key issues of the multimedia set-top-box used in active TV is conducted. Meanwhile a practical architecture for the multimedia set-top-box based on PC platform is designed. The architecture, with its advanced feature set, high integration and PCI interface is well suited to bring the set-top-box experience to consumers at an affordable price,and makes it very attractive for the consumer.

关键词： Set-top-box MPEG-2 PC platform Active TV

Wavelet-Based Fractal Function Approximation

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Journal of Systems Engineering and Electronics 1999年第4期10卷 60-66页

作者： Zhang Hejei tao ran zhou siyong & wang yue(Department of Electronic Engineering, Beijing Institute of Technology, 100081, P. R. China) Department of Electronic Engineering Beijing Institute of Technology 100081 P. R. China

In this paper, we study on the application of radical B-spline wavelet scaling function in fractal function approximation system. The paper proposes a wavelet-based fractal function approximation algorithm in which the coefficients can be determined by solving a convex quadraticprogramming problem. And the experiment result shows that the approximation error of this algorithm is smaller than that of the polynomial-based fractal function approximation. This newalgorithm exploits the consistency between fractal and scaling function in multi-scale and multiresolution, has a better approximation effect and high potential in data compression, especially inimage compression.

关键词： B-spline Wavelet scaling function Fractal function Approximation Quadratic programming.

Persistent greening against drying in northeast Asian semiarid grasslands:Asymmetrical responses of direct and legacy effects to intensified drought

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Advances in Climate Change Research 2024年第1期15卷 9-20页

作者： Yu-Tong MA Hai-shan CHEN Yao-Ming SONG Bo-tao zhou shan-Lei SUN Xin-Guan DU yue SUN Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China School of Atmospheric Sciences Nanjing University of Information Science and TechnologyNanjing 210044China

Despite experiencing a decadal shift towards drought conditions at the end of the 2Oth century,semiarid grasslands in northeast Asia(NEA)exhibited an evident greening trend from 1982 to ***,the mechanism behind this phenomenon remains ***,we analysed the interdecadal changes in vegetation response to drought on the basis of the standardised precipitation evapotranspiration index(SPEI)and Global Inventory Modelling and Mapping Studies LAI4g datasets,with an emphasis on the differences between direct and legacy effects(as measured by resilience),to explore the mechanism of persistent grassland *** revealed that during the post-drought shift period(2000-2020),the sudden decrease in the water content of the intermediate soil layer triggered an intensified vegetation response to ***,although direct effects and resilience were amplified,they exhibited asymmetric *** was stronger than direct effects,and this difference increased with increasing drought(drought recovery)*** combined effects may account for persistent greening against intensified drying in the semiarid grasslands in *** the projected exacerbation of future droughts,this study holds notable importance for comprehending the long-term change dynamics of dryland ecosystems.

关键词： Semiarid grassland Drought decadal shift Direct effect Legacy effect(resilience) Northeast Asia

Anti-tumor and Phenotypic Regulation Effect of Matrine on Dendritic Cells through Regulating TLRs Pathway

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Chinese Journal of Integrative Medicine 2021年第7期27卷 520-526页

作者： wang Jing-kang ZHAO Bao-sheng wang Min LIU Chen-yue LI Ya-qi MA Quan-tao LI Peng-fei wang Tie-shan wang Chun-guo zhou Yong-ming School of Chinese Materia Medica Beijing University of Chinese MedicineBeijing100029China Beijing Research Institute of Chinese Medicine Beijing University of Chinese MedicineBeijing100029China School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijing100029China Department of Oncology Guang'anmen HospitalChina Academy of Chinese Medical SciencesBeijing100053China

Objective To investigate the effects of matrine on antigen presentation of dendritic cells(DCs),and to explore the pharmacological mechanism of matrine on anti-tumor *** Different concentrations(0,1,2,4,8 and 16µg/mL)of matrine were co-cultured with DCs,the harvested DCs were co-cultured with antigens of Lewis lung cancer(LLC)cells,and then DCs and T cells were co-cultured to produce DCs-activated killer(DAK)cells,which have significant tumor-killing *** expression of cytokines,mRNA and protein of toll-like receptors(TLRs)in DCs were detected by enzyme linked immunosobent assay,polymerase chain reaction and Western blot,*** the killing effect of DAK were measured by MTT *** Matrine significantly increased the mRNA expression of TLR7,TLR8,myeloid differentiation factor 88(MyD88),tumor necrosis factor receptor-associated factor 6(TRAF-6)and IκB kinase(IKK),as well as the protein expression of TLR7 and TLR8,and up-regulated the levels of interleukin-12(IL-12),IL-6 and tumor necrosis factor-α(TNF-α),meanwhile,it also increased the expressions of MHC-II,CD54,CD80 and CD86 in ***-activated effector T cells had significant tumor-killing *** the concentration of matrine was more than 4µg/mL,all indices had significant difference(Pransduction pathway,promoting the secretion of inflammatory cytokines and enhancing immune function.

关键词： matrine Chinese medicine dendritic cells tumors toll-like receptors inflammatory cytokines