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用于导弹系统性能统计分析的统计线性化伴随法 总被引:1,自引:0,他引:1
本文在研究SLAM方法基础上,进行了理论推导和计算方法方面的改进,并将此方法应用于导弹系统性能的统计分析,计算机仿真结果表明该方法与采用CADET方法的结果完全一致。 相似文献
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Sabiha Tunçel Güçtekin Selçuk Bilir Salih Karaali Olcay Plevne Serap Ak 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2019,63(3):1360-1373
We used the ugr magnitudes of 1437467 F-G type main-sequence stars with metal abundance dex and estimated radial and vertical metallicity gradients for high Galactic-latitude fields, and , of the Milky Way Galaxy. The radial metallicity gradient dex kpc?1 estimated for the stars with kpc is attributed to the thin-disc population. While, the radial gradients evaluated for stars at higher vertical distances are close to zero indicating that the thick disc and halo have not undergone a radial collapse phase at least at high Galactic latitudes. The vertical metallicity gradients estimated for stars with three different Galactic latitudes, and do not show a strong indication for Galactic latitude dependence of our gradients. The thin disc, kpc, with a vertical metallicity gradient dex kpc?1, is dominant only in galactocentric distance interval kpc, while the thick disc ( kpc) could be observed in the intervals and kpc with compatible vertical metallicity gradients, i.e. dex kpc?1 and dex kpc?1. Five vertical metallicity gradients are estimated for the halo ( kpc) in three galactocentric distance intervals, and kpc. The first one corresponding to the interval kpc is equal to dex kpc?1, while the others at larger galactocentric distances are close to zero. We derived synthetic vertical metallicity gradients for 2,230,167 stars and compared them with the observed ones. There is a good agreement between the two sets of vertical metallicity gradients for the thin disc, while they are different for the thick disc. For the halo, the conspicuous difference corresponds to the galactocentric distance interval kpc, while they are compatible at higher galactocentric distance intervals. 相似文献
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Anoop Mishra R.M. Gairola A.K. Varma Abhijit Sarkar Vijay K. Agarwal 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009,44(7):815-823
Present study focuses on the estimation of rainfall over Indian land and oceanic regions from the Special Sensor Microwave/Imager (SSM/I) on the Defense Meteorological Satellite Program (DMSP) F-13. Based on the measurements at 19.35, 22.235 and 85.5 GHz channels of SSM/I Satellite, scattering index (SI) has been developed for the Indian land and oceanic regions separately. These scattering indices were co-located against rainfall from Precipitation Radar (PR) onboard Tropical Rainfall Measuring Mission (TRMM) to develop a new regional relationship between the SI and the rain rate for the Indian land and oceanic regions. A non-linear fit between the rain rate and the SI is established for rain measurement. In order to have confidence in our method, we have also estimated rainfall using the global rainfall and scattering index relationship developed by Ferraro and Marks [Ferraro, R.R., Marks, G.F. The development of SSM/I rain rate retrieval algorithms using ground based radar measurements. J. Atmos. Ocean. Technol. 12, 755–770, 1995]. The validation with the rain-gauge shows that the present scheme is able to retrieve rainfall with better accuracy than that of Ferraro and Marks (1995). Further intercomparison with TRMM-2A12 and validation with rain-gauges rainfall showed that the present algorithm is able to retrieve the rainfall with reasonably good accuracy. 相似文献
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基于人工势场法的移动机器人最优路径规划 总被引:5,自引:1,他引:5
提出一种解决人工势场法目标不可达问题的方法.分析了传统人工势场法中的固有缺陷:目标不可达;在障碍物附近或通过狭小通道时的抖动问题.通过选取适当的增益系数解决了目标不可达问题,使机器人快速到达目标点.用拉紧法去除路径的冗余节点并用极坐标下对称多项式优化出圆滑的最优路径.仿真结果证实了所提方法的正确性和有效性. 相似文献