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OALib Journal期刊

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The aperture averaging effect of scintillation of pseudo-partially Gaussian-Schell model beam propagation in turbulent atmosphere
伪部分相干高斯-谢尔模型光束在湍流大气中传播的闪烁孔径平滑效应

Qian Xian-Mei,Zhu Wen-Yue,Rao Rui-Zhong,<br>,朱文越,饶瑞中
物理学报 , 2013,
Abstract: By using numerical simulation, the propagation of pseudo-partially coherent Gaussian-Schell model beam in atmospheric turbulence is simulated. The properties of intensity fluctuation of different receiving aperture and aperture averaging factors are statistically analyzed. And the influence of relative changing frequency of the modulating phase which models the partial coherence of beam source on scintillation index is also discussed. The simulation results of pseudo-partially coherent beam are compared with those of the well-developed partially coherent beam and fully coherent Gaussian beam. It is found that the reduction of coherence degree may cause scintillation index to decrease. However, the aperture averaging effect is weakened at the same time. At the same receiving aperture diameter, the aperture averaging factor of pseudo-partially coherent beam is greater than that of the fully coherent beam. The increase of relative changing frequency of modulating phase may cause a reduction of scintillation index to some degree. And with the increase of relative changing frequency, the scintillation index of pseudo-partially coherent beam tends to be coincident with that of the partially coherent beam.
Phase screen distribution for simulating laser propagation along an inhomogeneous atmospheric path
非均匀湍流路径上光传播数值模拟的相位屏分布

Qian Xian-Mei,Zhu Wen-Yue,Rao Rui-Zhong,<br>,朱文越,饶瑞中
物理学报 , 2009,
Abstract: 针对非均匀湍流路径上光传播的数值模拟,研究了相位屏分布的三种不同设置方案,即均匀分布相位屏(UDPS)、等Rytov指数间隔的相位屏(ERPS)和等Fried参数间隔的相位屏(EFPS).结果表明,ERPS方案根据折射率起伏的强弱设置密疏相间的相位屏,实现了对不同折射率起伏区的充分采样,是非均匀路径上相位屏分布的首选方案.在满足相位屏间距基本要求的前提下,决定相位屏间隔的Rytov指数间隔的选取具有较大的任意性,统计结果显示,尽管相位屏间Rytov指数变化超过一个数量级,但光束有效半径、能量Strehl比的变化均小于2.1%,模拟结果与理论结果符合很好,表明了ERPS方案的可靠性和稳定性.
Numerical Investigation into Focal Shift of Gaussian Beam Propagating in Turbulent Atmosphere
湍流大气中高斯光束焦移的数值模拟研究

QIAN Xian-mei,ZHU Wen-yue,RAO Rui-zhong,<br>,朱文越,饶瑞中
光子学报 , 2008,
Abstract: The focal shift of a focused Gaussian beam propagating in turbulent atmosphere is investigated using numerical simulation. It is found that the focus always shifts toward the transmitter, and the length of the focal shift will increase with the increasing of turbulence strength.These results are in excellent agreement with theoretical results. By using focal depth the collimated characteristic of beam near focus is described. Simulation results show that focal depth increases with turbulence strength for weak to moderate turbulence, and in cases of moderate to strong turbulence the beam is highly collimated on both sides of the beam waist.
Demodulation Algorithm for the Measurement of Atmospheric Optical Turbulence with Fiber Optics
大气光学湍流光纤测量技术中的解调算法研究

HAO Lei,MEI Hai-ping,QIAN Xian-mei,ZHU Wen-yue,RAO Rui-zhong,<br>郝磊,梅海平,,朱文越,饶瑞中
光子学报 , 2008,
Abstract: Principle of measuring atmospheric optical turbulence by using fiber Mach-Zehnder interferometer with a directly modulated light source was introduced.The processes of carrier frequency modulation and demodulation were also deeply researched.Through the computer simulation of the optical turbulence induced phase fluctuation,carrier frequency modulation and demodulation,the feasibility of measuring atmospheric optical turbulence by the principle was demonstrated.And,a new signal processing procedure for the algorithm was proposed.
Selection of Computing Parameters in Numerical Simulation of Laser Beam Propagation in Turbulent Atmosphere
激光湍流大气传输数值模拟中计算参量的选取

QIAN Xian-mei,ZHU Wen-yue,HUANG Yin-bo,RAO Rui-zhong,<br>,朱文越,黄印博,饶瑞中
光子学报 , 2008,
Abstract: Based on sample principles,properties of turbulent media,turbulent effects and light propagating effects,criterions for grid interval,inter-screen distance and number of grid were analyzed.By numerical analysis,it is shown that not all of these criterions can be satisfied simultaneously in most simulations.If parameters were selected strictly according to these criterions,the demand of calculation would be out of reach of a computer.Then,taking into account the burden that a computer can bear and simulated precision,a reliable and applicable method of the selection of crucial computing parameters was presented.
漂移对聚焦高斯光束闪烁影响的数值模拟
,朱文越,饶瑞中
强激光与粒子束 , 2007,
Abstract: ?采用非自适应坐标变换对聚焦高斯光束在湍流大气中的传输进行了数值模拟,结果显示轴闪烁指数并没有出现如rytov理论所预言的随初始光束半径的增大而明显减小的现象,其原因在于rytov近似理论未考虑大尺度湍涡产生的漂移效应对闪烁的贡献。对比数值模拟结果与漂移理论结果以及相关实验结果,三者相吻合,表明未考虑漂移效应的rytov近似理论不能完全准确地描述聚焦光束的闪烁特征,在研究聚焦光束的闪烁时,应当考虑漂移的影响。
近地层大气光学湍流的分形和间歇性特征分析
王倩,梅海平,肖树,黄宏华,,朱文越,饶瑞中
强激光与粒子束 , 2014,
Abstract: ?利用光纤湍流测量系统获得了合肥西郊科学岛上气象观测场内下垫面平坦的水面上方0.48m、草地上方1.8m和23m高处的大气折射率起伏的观测数据,采用r/s分析法计算了近地层大气光学湍流的赫斯特指数和分形维数,统计分析了分形维数的日变化特征及概率分布特征。结果表明:对于一天的不同时段,分形维数在一定范围内动态变化,且中午时段相对稳定;在三种下垫面条件下,全天分形维数的值大多在1.3~1.4之间,其最可几概率位于1.35处,从均值来看,草地上方1.8m的分形维数最大,水面上方0.48m次之,草地上方23m处最小。最后,初步探讨了近地层大气光学湍流分形维数、间歇性指数和湍流发展程度的相关性。
自动发电控制在江苏电网的开发应用

电力系统自动化 , 1997,
Abstract: 介绍自动发电控制(AGC)在江苏电网的开发应用情况,就硬件系统结构、系统功能、调试运行结果等方面介绍建立在N—90机炉协调基础上的AGC闭环控制调节和利用国产火电机组调功装置HGT按机组负荷曲线调节的AGC控制。
噁草酮和丙炔噁草酮对5种稻田杂草室内活性的比较
Bioactivity of Oxadiazon and Oxadiargyl to 5 Weeds of Rice Paddy
 [PDF]

忠海, 潘登, 宋立, 张军民
Botanical Research (BR) , 2014, DOI: 10.12677/BR.2014.31004
Abstract: 采用土壤浇灌法和茎叶喷雾法在室内测定了噁草酮和丙炔噁草酮对稗草、千金子、鸭舌草、鳢肠和碎米莎草的生物活性。结果表明,用土壤浇灌法,噁草酮对千金子、鸭舌草、碎米莎草、稗草和鳢肠IC90分别为13.9823.4335.48247.58 561.78 g a.i./hm2;丙炔噁草酮对鸭舌草、碎米莎草、千金子、稗草和鳢肠IC90分别为15.5324.4228.0854.38 98.35 g a.i./hm2。用茎叶喷雾法,噁草酮对碎米莎草、鸭舌草、千金子、稗草和鳢肠IC90分别53.01111.57187.11342.75 and 425.34 g a.i./hm2;丙炔噁草酮对碎米莎草、千金子、鸭舌草、稗草和鳢肠IC90分别为14.8722.2122.6386.23 and 300.63 g a.i./hm2。测定结果表明丙炔噁草酮对供试
Rotation and vibration of diatomic molecule oscillator with hyperbolic potential function
Lu Jun,Qian Hui-Xian,Li Liang-Mei,Liu Feng-Ling,<br>陆军,,李良梅,柳凤伶
中国物理 B , 2005,
Abstract: The explicit expressions of energy eigenvalues and eigenfunctions of bound states for a three-dimensional diatomic molecule oscillator with a hyperbolic potential function are obtained approximately by means of the hypergeometric series method. Then for a one-dimensional system, the rigorous solutions of bound states are solved with a similar method. The eigenfunctions of a one-dimensional diatomic molecule oscillator, expressed in terms of the Jacobi polynomial, are employed as an orthonormal basis set, and the analytic expressions of matrix elements for position and momentum operators are given in a closed form.
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