不连续植被冠层辐射透过率和反射率的测量(英文)     

《遥感学报》1997,(Z1)

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几何光学冠层反射建模中的光谱分量特征的参数化(英文)     

倪文革  李小文  ＣｕｒｔｉｓＥ．Ｗｏｏｄｃｏｃｋ  ＡｌａｎＳｔｒａｈｌｅｒ 《遥感学报》1997,(Z1)

该文用几何光学与辐射传输混合模型研究不连续植被冠层的几何光学反射模型的四分量（承照树冠、承照地面、阴影树冠、阴影地面）的参数化。用一个修正的均匀介质层路径散射（反射与传输）参数的解析算法估计路径散射参数（反射与传输），其中也考虑了冠层间隙的影响。光谱分量特征是不连续植被冠层的传输与反射，背景反照率，以直射光通量与天空漫射光通量比例的函数。光谱分量特征的模型与在美国缅因州Ｈｏｌａｎｄ采集的针叶林数据吻合。基于ＬｉＳｔｒａｈｌｅｒ几何光学相互遮蔽模型，用参数化的光谱分量特征对老松林和老云杉林的方向反射进行估计，其结果与在不同太阳与观测方向上的ＰＡＲＡＢＯＬＡ测量值匹配得很好。  相似文献   

Improvements on particle swarm optimization algorithm for velocity calibration in microseismic monitoring          下载免费PDF全文

Yue Yang  Jian Wen  Xiaofei Chen 《地震科学（英文版）》2015,28(4):263-273

In this paper,we apply particle swarm optimization(PSO),an artificial intelligence technique,to velocity calibration in microseismic monitoring.We ran simulations with four 1-D layered velocity models and three different initial model ranges.The results using the basic PSO algorithm were reliable and accurate for simple models,but unsuccessful for complex models.We propose the staged shrinkage strategy(SSS) for the PSO algorithm.The SSS-PSO algorithm produced robust inversion results and had a fast convergence rate.We investigated the effects of PSO's velocity clamping factor in terms of the algorithm reliability and computational efficiency.The velocity clamping factor had little impact on the reliability and efficiency of basic PSO,whereas it had a large effect on the efficiency of SSS-PSO.Reassuringly,SSS-PSO exhibits marginal reliability fluctuations,which suggests that it can be confidently implemented.  相似文献   

On the high coherence of kHz quasi-periodic oscillations   总被引：1，自引：0，他引：1  

D. Barret  W. Klu&#;niak  J. F. Olive  S. Paltani  G. K. Skinner 《Monthly notices of the Royal Astronomical Society》2005,357(4):1288-1294

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Outbursts of selected dwarf novas and postnovas     

E. P. Pavlenko  S. Yu. Shugarov  D. N. Baklanova  N. A. Katysheva 《Bulletin of the Crimean Astrophysical Observatory》2008,104(1):109-118

Observations are presented of selected cataclysmic variables (the dwarf novas V1504 Cyg and GO Com and the postnovas Q Cyg, V446 Her, and DI Lac) carried out at the Crimean Astrophysical Observatory and the Crimean Laboratory of the Sternberg Astronomical Institute in 1995–2007. The outburst parameters and the behavior of these objects on the “magnitude (V)-color (V-R)” diagram are described. The tracks of postnova outbursts on this diagram are similar to the dwarf-nova behavior. On average, all the studied systems show a break on the “brightness-color” dependence. The color V-R before the break increases more weakly than after it or does not increase at all.  相似文献