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Research on Asynchronous Transfer of DTV Video Signal

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Semiconductor Photonics and Technology 1998年第4期 13-22页

作者： mao youju , HE Tingchang, FU Jun (Institute of Optical Communications,Chongqing University of Posts & Telecommunications,Chongqing 400065,CHN)

１ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｃｏｍｍｕｎｉｃａｔｉｏｎｎｅｔｗｏｒｋｉｎｔｈｅｆｕｔｕｒｅｗｉｌｂｅａｂｒｏａｄｂａｎｄｉｎｔｅｇｒａｔｅｄｓｅｒｖｉｃｅｄｉｇｉｔａｌｎｅｔｗｏｒｋ（Ｂ－ＩＳＤＮ），ｗｈｉｃｈｍ... 详细信息

１ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｃｏｍｍｕｎｉｃａｔｉｏｎｎｅｔｗｏｒｋｉｎｔｈｅｆｕｔｕｒｅｗｉｌｂｅａｂｒｏａｄｂａｎｄｉｎｔｅｇｒａｔｅｄｓｅｒｖｉｃｅｄｉｇｉｔａｌｎｅｔｗｏｒｋ（Ｂ－ＩＳＤＮ），ｗｈｉｃｈｍａｉｎｌｙｕｓｅｏｐｔｉｃａｌｆｉ...

关键词： Asynchronous Transfer Mode Digital TV Statistical Multiplexing

WDM+EDFA+DCF光纤传输系统中色散补偿方案的分析

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激光杂志 1999年第6期20卷 28-31页

作者：毛幼菊汪学强重庆邮电学院重庆400065

由于在ＷＤＭ＋ＥＤＦＡ光纤传输系统中使用常规单模光纤（ＳＭＦ）在１５５０ｎｍ窗口的大色散限制了传输距离，采用色散补偿光纤（ＤＣＦ）进行色散补偿是目前一种较为理想的方法。本文基于光纤ＷＤＭ＋ＥＤＦＡ＋ＤＣＦ的长距离... 详细信息

由于在ＷＤＭ＋ＥＤＦＡ光纤传输系统中使用常规单模光纤（ＳＭＦ）在１５５０ｎｍ窗口的大色散限制了传输距离，采用色散补偿光纤（ＤＣＦ）进行色散补偿是目前一种较为理想的方法。本文基于光纤ＷＤＭ＋ＥＤＦＡ＋ＤＣＦ的长距离传输系统，讨论了ＤＣＦ色散补偿对光纤非线性效应交叉相位调制（ＸＰＭ）和四波混频（ＦＷＭ）的影响，提出了采用ＤＣＦ集总、后置、非完全补偿的色散补偿方案。

关键词：色散补偿光纤传输系统 WDM EDFA DCF

一种基于凸集投影(POCS)的数字图像超分辨率重建算法

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计算机工程与应用 2005年第4期41卷 69-71页

作者：庞亚红毛幼菊重庆邮电学院光通信研究所重庆400065

该文研究了一种基于凸集投影(POCS)算法的超分辨率图像重建方法,分析了POCS方法恢复图像的理论算法,通过仿真对比了其与双线性插值方法恢复超分辨率图像的差异,仿真结果表明,该方法明显地提高了超分辨率图像的恢复质量。

关键词：超分辨率图像恢复凸集投影

Simulation and evaluation study of atmospheric aerosol nonsphericity as a function of particle size

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Particuology 2024年第7期90卷 281-291页

作者： Qianjun mao Xin Nie School of Urban Construction Wuhan University of Science and TechnologyWuhan430065China College of New Energy and Materials Northeast Petroleum UniversityDaqing163318China

Aerosol nonsphericity causes great uncertainty in radiative forcing assessments and climate *** considerable studies have attempted to quantify this uncertainty,the relationship between aerosol nonsphericity and particle size is usually not considered,thus reducing the accuracy of the *** this study,a coupled inversion algorithm combining an improved stochastic particle swarm optimization algorithm and angular light scattering is used for the nonparametric estimation of aerosol nonsphericity variation with particle size,and the optimal sample selection method is employed to screen the *** on the verification of inversion accuracy,the variation of aerosol aspect ratio with particle size based on the ellipsoidal model in global regions has been obtained from Aerosol Robotic Network(AERONET)data,and the effect of nonsphericity on radiative forcing and dry deposition has been *** results show that the aspect ratio increases with particle size in all regions,with the maximum ranging from 1.4 to 1.8 in the desert,reflecting the differences in aerosol composition at different particle *** radiation calculations,considering aerosol nonsphericity makes the aerosol cooling effect weaker and surface radiative fluxes increase,but hardly changes the aerosol absorption,with maximum differences of 9.22%and 22.12%at the bottom and top of the atmosphere,***,the differences in radiative forcing between aspect ratios as a function of particle size and not varying with particle size are not significant,averaging less than 2%.Besides,the aspect ratio not varying with particle size underestimates the deposition velocity of small particles and overestimates that of large particles compared to that as a function of particle size,with maximum differences of 7%and 4%,respectively.

关键词： Aerosol nonsphericity Inversion Aspect ratio Radiative forcing Dry deposition velocity

Proof of Two Supercongruences of Truncated Hypergeometric Series_(4)F_(3)

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1015-1028页

作者： Guo Shuai mao Department of Mathematics Nanjing University of Information Science and TechnologyNanjing 210044P.R.China

In this paper,we prove two supercongruences conjectured by Z.-*** via the Wilf-Zeilberger *** of them is,for any prime p>3,4F3[7/6 1/2 1/2 1/2 1/6 1 1]-1/8]-1/2≡p(-2/p)+p^(3)/4(2/p)Ep-3 (mod p^(4))where(·/p)stands f... 详细信息

关键词： Supercongruence truncated hypergeometric series Wilf–Zeilberger method Euler numbers Legendre symbol

Dynamic steric confinement effect expands the frontier of Cu-catalyzed asymmetric propargylic aminations

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Science China Chemistry 2024年第10期67卷 3181-3183页

作者： Peng Chen mao-mao Zhang Wen-Jing Xiao Liang-Qiu Lu Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction Ministry of EducationCollege of ChemistryCentral China Normal University Wuhan Institute of Photochemistry and Technology State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics (LICP)Chinese Academy of Sciences School of Chemistry and Chemical Engineering Henan Normal University

Chiral α-tertiary amines and related azacycles are commonly found in many natural products, pharmaceuticals and agrochemicals [1]. Copper-catalyzed asymmetric propargylic amination(APA) reactions have been established as a reliable method to access enantio-enriched propargylic amines,largely due to the seminal contribution of Nishibayashi et al.[2] and van Maarseveen et al. [3] in 2008.

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Heat Storage Performance of PCM in a Novel Vertical Pointer-Shaped Finned Latent Heat Tank

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Journal of Thermal Science 2024年第2期33卷 422-434页

作者： mao Qianjun ZHU Yuanyuan LI Tao School of Urban Construction Wuhan University of Science and TechnologyWuhan430065China

The heat storage performance of latent heat storage systems is not good due to the poor thermal conductivity of phase change *** this paper,a new type of pointer-shaped fins combining rectangular and triangular fins has been employed to numerically simulate the melting process in the heat storage tank,and the fin geometry parameter effects on heat storage performance have been *** results indicate that compared with the bare tube and the rectangular finned tank,the melting time of the phase change material in the pointer-shaped finned tank is reduced by 64.2%and 15.1%,*** closer the tip of the triangular fin is to the hot wall,the better the heat transfer *** optimal height of the triangular fin is about 8 *** the number of fins from 4 to 6 and from 6 to 8 reduces the melting time by 16.0%and 16.7%***,increasing the number of fins from 8 to 10 only reduces the melting time by 8.4%.When the fin dimensionless length is increased from 0.3 to 0.5 and from 0.5 to 0.7,the melting time is shortened by 17.5%and 13.0%.But the melting time is only reduced by 2.9%when the dimensionless fin length is increased from 0.7 to *** optimising the design of the thermal storage system,the results can provide a reference value.

关键词： thermal energy storage phase change material pointer-shaped fins heat storage performance

Equilibrium Strategy of the Pursuit-Evasion Game in Three-Dimensional Space

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 446-458页

作者： Nuo Chen Linjing Li Wenji mao School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049 Institute of Automation Chinese Academy of SciencesBeijing 100190China

The pursuit-evasion game models the strategic interaction among players, attracting attention in many realistic scenarios, such as missile guidance, unmanned aerial vehicles, and target defense. Existing studies mainly concentrate on the cooperative pursuit of multiple players in two-dimensional pursuit-evasion games. However, these approaches can hardly be applied to practical situations where players usually move in three-dimensional space with a three-degree-of-freedom control. In this paper,we make the first attempt to investigate the equilibrium strategy of the realistic pursuit-evasion game, in which the pursuer follows a three-degree-of-freedom control, and the evader moves freely. First, we describe the pursuer's three-degree-of-freedom control and the evader's relative coordinate. We then rigorously derive the equilibrium strategy by solving the retrogressive path equation according to the Hamilton-Jacobi-Bellman-Isaacs(HJBI) method, which divides the pursuit-evasion process into the navigation and acceleration phases. Besides, we analyze the maximum allowable speed for the pursuer to capture the evader successfully and provide the strategy with which the evader can escape when the pursuer's speed exceeds the threshold. We further conduct comparison tests with various unilateral deviations to verify that the proposed strategy forms a Nash equilibrium.

关键词： Differential game equilibrium strategy pursuit-evasion game threedegree-of-freedom control

First Passage Density of Brownian Motion with Two-sided Piecewise Linear Boundaries

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1505-1520页

作者： Zhen YU mao Zai TIAN Center for Applied Statistics School of StatisticsRenmin University of ChinaBeijing 100872P.R.China School of Mathematics and Data Science Changji UniversityChangji 831100P.R.China

The first passage time has many applications in fields like finance,econometrics,statistics,and ***,explicit formulas for the first passage density have only been obtained for a few *** paper derives an explicit formula for the first passage density of Brownian motion with twosided piecewise continuous boundaries which may have some points of *** are used to obtain a simplified formula for estimating the first passage ***,the results are also generalized to the case of two-sided general nonlinear *** can be easily carried out with Monte Carlo method and it is demonstrated for several typical two-sided boundaries that the proposed approximation method offers a highly accurate approximation of first passage density.

关键词： Boundary non-crossing probability first density passage density two-sided piecewise continuous boundaries Brownian motion