oalib

OALib Journal期刊

ISSN: 2333-9721

费用:99美元

投稿

时间不限

2016 ( 73 )

2015 ( 2344 )

2014 ( 2249 )

2013 ( 2348 )

自定义范围…

匹配条件: “饶瑞中” ,找到相关结果约38881条。
列表显示的所有文章,均可免费获取
第1页/共38881条
每页显示
从光闪烁频谱反演大气湍流谱:原理与数值模拟

力学学报 , 2002, DOI: 10.6052/0459-1879-2002-5-2001-083
Abstract:
湍流大气中的准直激光束iii.分形结构与相位不连续点饶瑞中

强激光与粒子束 , 2002,
Abstract: ?利用数值方法研究了不同起伏条件下准直激光束在湍流大气中的传播,分析了光斑的分形维数以及相位不连续点数目的统计特征。结果表明:随着起伏条件的增大,光斑的分形维数以及相位不连续点数目增大;光斑的分形维数与锐度(描述光斑质量的参量)有一定的关系,但相位不连续点数目与光斑质量不存在确定的关系。在本文的计算条件下,分形维数一直随起伏条件的增大而增大,没有出现类似于闪烁饱和的现象。在一定的起伏条件下,相位不连续点数目具有一定的统计分布,而不是一个确定的值,并且具有相当的发散性。
海雾对3~5μm和8~14μm红外辐射的衰减特性
,宋正方
红外与毫米波学报 , 1989,
Abstract: 分析了Khrgian-Mazin模型描述雾的粒度谱分布的可靠性,利用该模型和米氏散射理论计算了世界上典型地区的海雾对3~5μm和8~14μm大气窗红外辐射的衰减,并将计算结果和红外波段内的10.6μm激光辐射在雾中衰减的实测结果相比较,得出了两个大气窗内海雾对红外辐射展减的一般规律.
空间斜程能见度的影响因素分析
王毅,
强激光与粒子束 , 2003,
Abstract: ?空间斜程能见度是空间目标识别的重要参量。水平能见度与大气消光参数有明确的关系,而斜程能见度与大气消光参数、观测方向、太阳天顶角等多种因素有关,目前尚未有明确的结果。从辐射传输理论出发,通过δ-eddington近似求解辐射传输方程,尝试推导了空间斜程能见度的表达式,探讨了斜程能见度与观察者视角、太阳高度角以及大气光学特性之间的关系。
RETRIEVAL OF TURBULENCE SPECTRUM FROM TEMPORAL SPECTRUM OF A LIGHT WAVE PROPAGATING THROUGH ATMOSPHERE: PRINCIPLE AND SIMULATIONS
从光闪烁频谱反演大气湍流谱:原理与数值模拟

Rao Ruizhong,

力学学报 , 2002,
Abstract: A numerical algorithm is set up for the retrieval of optical turbulence spectrum from high-frequency temporal spectra of a light wave propagating through a turbulent atmosphere. This technique has two advantages. First, the retrieved spectrum is directly related to the refractive index fluctuation rather than temperature fluctuation. Second, the turbulence spectrum at rather high spatial wavenumber, most in the dissipation range, can be retrieved. We test the retrieval procedure through carrying out a lot of simulations with Hill turbulence model and a composed model. It is found that if the wind velocity and the turbulence inner scale are known correctly the turbulence spectrum can be achieved effectively.
Wavelength Band Selection Method for Target Detection Considering Surface Reflectivity
根据表面反射特性进行目标探测的波段选择

范 伟,王 毅,
光子学报 , 2006,
Abstract: The influence on target detection of surface reflective character was computed and analyzed in the article. By introducing the orthogonal complement subspace projection method, the background signal was eliminated from the receiving mixture signal. Therefore the aim to compress the background signal was achieved. On the basis of the remaining signal, the matching pursuit algorithm was adopted to select the optimal wavelength bands automatically. Aiming at selecting the optimum wavelength bands was achieved and the target can be detected. The algorithm was applied to target detection out of the atmosphere. At last the relation between the wavelength band selection for target detection out of the atmosphere and the targetrs surface reflective character was obtained.
近海边高空光学湍流的探空测量与模式比较
吴晓庆,方强,
强激光与粒子束 , 2006,
Abstract: ?用自行研制的探空仪测量了近海边高空湍流廓线。探空气球携带微温传感器以4m·s-1速度上升至20km测量大气湍流,微温传感器附加在59型气象探空仪上,可同时测量垂直空间分辨率为30m的气压、温度和湿度以及折射率结构常数。运用tatarskii公式计算了高空湍流外尺度,分析了边界层湍流和自由大气层湍流特征。与afglamos模式、hufnagel模式以及北京天文台兴隆站的探空拟合曲线进行的比较发现,海边测量的高空湍流强度比其它模式大2个量级,折射率结构常数随高度从表面层较大值以近似相同的递减率缓慢地减小,对流层顶附近没有出现较强的湍流区,外尺度测量值小于30m,并得到外尺度的拟合曲线。
大气中目标背景对比度及其影响因素的数值分析
王毅,范伟,
强激光与粒子束 , 2004,
Abstract: ?从辐射传输理论出发,利用离散纵标法软件包(disort),计算了典型大气条件下0.55μm波长的目标背景对比度,分析了观察者的天顶角和方位角、水平能见度、垂直高度、太阳的天顶角和方位角以及气溶胶单次散射反照率对目标背景对比度的影响。结果表明:目标背景对比度随着观察者天顶角余弦的增加而增加;随着太阳天顶角余弦的增加而减小;随着观察者和太阳方位角差的增加而增加;随着高度的增加而减小;随着水平能见度的增加而增加;随着单次散射反照率的增加而减小。
减背景的波段选择算法及其在目标探测中的应用
范伟,王毅,
强激光与粒子束 , 2005,
Abstract: ?介绍了正交子空间投影方法,这种方法可将背景信号从接收到的混合光谱中消除,在此基础上运用匹配跟踪算法自动地进行优化波段的选择,达到选择最佳波段进行目标探测的目的。将其运用到大气外目标探测的问题,得到了较好的探测波段的结果,说明此方法选择优化波段进行目标探测是有效的。
NUMERICAL ANALYSIS OF LIGHT SCATTERING BY RANDOMLY ORIENTED CUBIC PARTICLES
随机取向立方粒子光散射的数值分析

RAO RUI-ZHONG,

物理学报 , 1998,
Abstract: Numerical calculations were carried out on light scattering by randomly oriented cubic particles for several size parameters. The scattering properties were analyzed and compared with those of the equivalent spherical particles. Results show that the differences between the scattering properties of cubic and spherical particles are similar to those between other non-spherical and spherical particles. The results imply the intrinsic symmetry and discontinuity of the normal direction of the particle surface have little effects on the scattering properties.
第1页/共38881条
每页显示


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.