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81.
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83.
Three selected asteroids, numbered 58, 360 and405, were observed during 2000at Yunnan Observatory, China. Thenew lightcurves are presented inthis paper. The synodic period of (58)Concordia is estimated as 9.90 ± 0.01hfor the first time. The synodic period of (405) Thia derived from ourobservation is 9.96 ± 0.01h, which is slightly different from the previousresult. For 360, we obtained the synodic period of 6.18 ± 0.02h which isconsistent with previous values. Additionally, the BV and UB-colourindexes for the three asteriods were also determined. 相似文献
84.
One of the main limitations to the sensitivity of the infrared camera ISOCAM on-board the Infrared Space Observatory (ISO)
comes from responsivity variations and glitches caused by the impacts of charged particles in photo-detectors. Glitch rate
measurements, glitch properties and removal methods have already been addressed during the first ISO detector workshop(Madrid,
1998) and published in a special issue of Experimental Astronomy. It appeared that glitch rate and most of glitch properties
could be reproduced by Monte-Carlo simulations. This is very interesting in order to predict before launch the effect of charged
particles in photo-detectors operated in space. This paper presents results of Monte-Carlo simulations of radiation effects
on ISOCAM detectors. Glitch rates, spatial and energetic properties of glitches have been computed and are compared with measured
values.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
85.
2012年辽宁省测绘地理信息局将利用UCD+POS AV 510资料进行约30 000 km2的1∶10 000基本地形图更新。本文从用户的角度,以GeolordAT空三加密软件平台为基础,详细阐述了针对UCD+POS数据,进行资料分析、数据处理、空三加密的步骤、方法、精度和注意事项等,并得出切实可行的像控网布设方案。 相似文献
86.
利用有理函数模型替代严格传感器模型已经成为当前高分辨率遥感影像通用的数据标准.对于附加有理函数模型系数的线阵CCD遥感影像,提出了一种利用反解有理函数模型实现倾斜像片与水平像片转换方法.其主要原理同传统框幅式倾斜影像与水平影像的转换相似:将倾斜像片上像点投影到物方水平面上;然后在物方水平面上根据原始倾斜像片的地面采样间... 相似文献
87.
88.
The MPC database of the asteroid observations (each position from near 20 millions) was used in analysis of observational accuracy for more than 300 active world observatories both professional and amateur. The values of the “Mean error of a single observation” σ (for α,δ) were derived based on the Pulkovo method of accuracy estimation. These values may be used for observatory weight assignment in the orbital improvement procedures. The accuracy of the best amateur observations is proved to be comparable with professional one (σ=±0″.20). The detailed results in electronic format are accessible from the first author. 相似文献
89.
Josep M. Trigo-Rodriguez José M. Madiedo Peter S. Gural Alberto J. Castro-Tirado Jordi Llorca Juan Fabregat Standa Vítek Pep Pujols 《Earth, Moon, and Planets》2008,102(1-4):231-240
By using high-resolution, low-scan-rate, all-sky CCD cameras, the SPanish Meteor Network (SPMN) is currently monitoring meteor
and fireball activity on a year round basis. Here are presented just a sampling of the accurate trajectory, radiant and orbital
data obtained for meteors imaged simultaneously from two SPMN stations during the continuous 2006–2007 coverage of meteor
and fireball monitoring. Typical astrometric uncertainty is 1–2 arc min, while velocity determination errors are of the order
of 0.1–0.5 km/s, which is dependent on the distance of each event to the station and its particular viewing geometry. The
cameras have demonstrated excellent performance for detecting meteor outbursts. The recent development of automatic detection
software is also providing real-time information on the global meteor activity. Finally, some examples of the all-sky CCD
cameras applications for detecting unexpected meteor activity are given. 相似文献
90.
提出一种能够在强约束条件下快速进行相机标定的方法。通过相机间6个相互独立的约束,充分利用系统的几何条件,确定相邻立体相机的固有关系;再以共线方程为基础推导强约束条件下的平差模型,并应用于自检校光束法平差,从而实现多相机系统的快速标定;最后利用改进的PMVS三维重建方法开展标定后系统的人体三维重建。实验表明,通过加入强约束条件,增加平差的多余观测数,提高了标定精度和鲁棒性,对三维重建的精度亦有较大提高,并且该方法可推广到多个相机组成的多相机立体量测系统的标定中。 相似文献