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Review on abort trajectory for manned lunar landing mission

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Science China(Technological Sciences) 2010年第10期53卷 2691-2698页

作者： XI XiaoNing1, HUANG WenDe2.& WANG Wei2.3 1 College of Mechatronics Engineering and Automation, National University of Defense Technology, Changsha 410073, China 2.College of Aerospace and Material Engineering, National University of Defense Technology, Changsha 410073, China 3 school of surveying and spatial information system, University of new {2. wales, sydney, nsw 2.52. australia 1. College of Mechatronics Engineering and Automation National University of Defense Technology Changsha 410073 China2. College of Aerospace and Material Engineering National University of Defense Technology Changsha 410073 China3. School of Surveying and Spatial Information System University of New South Wales Sydney NSW 2052 Australia

Abort trajectory is a passage that ensures the astronauts to return safely to the earth when an emergency occurs. Firstly,the essential elements of mission abort are analyzed entirely based on summarizing the existing studies. Then,abort trajectory requirement and rational selection for different flight phases of typical manned lunar mission are discussed specifically. Considering a trade-off between the two primary constrains of an abort,the return time of flight and energy requirement,a general optimizing method for mission abort is proposed. Finally,some suggestions are given for China’s future manned lunar landing mission.

关键词： manned lunar landing mission abort trajectory design free return trajectory

Methods of 3D map storage based on geo-referenced image database

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中国有色金属学会会刊：英文版 2011年第S3期21卷 654-658页

作者： YUAN Zhan-liang1, 2. LI Xun1, WANG Jin-ling1, YUAN Qi-qi1, XU Dan2. DIAO Jing-jing2.1. school of surveying and {2. information systems, University of new south wales, nsw 2.32. australia 2. school of surveying and Mapping, Henan Polytechnic University, Jiaozuo 454000, China [a] school of surveying and {2. information systems University of New South Wales NSW 2032 Australia [b] school of surveying and Mapping Henan Polytechnic University Jiaozuo 454000 China

In order to store and manage a large amount of ground and indoor image data with high resolution, an integrated data management system needs to be developed. Possible strategies for this purpose were discussed together with initial test on the newly defined 3D maps. The features of such 3D maps, data organization, key techniques used for the map storage, such as image compression based on wavelet transformation, quadtree index, update and retrieval, were analyzed, with the goals of bringing some profits to the storage and management of the digital data in the visual construction of digital mine, digital city and digital community.

关键词： 3D map geo-referenced image image database storage technology

基于载波相位误差EMD-Wavelet消除模型的GPS精密静态定位研究(英文)

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基于载波相位误差EMD-Wavelet消除模型的GPS精密静态定位研究(英...

中国测绘学会第九次全国会员代表大会暨学会成立50周年纪念大会

作者： Jian Wang, Jinling Wang and Craig Roberts school of surveying and {2. information systems The University of new south wales sydney nsw 2.52. australia

In this paper, a new EMD-Wavelet based model is used to reduce carrier phase errors for precise static GPS positioning. The EMD is a new signal processing method for analysing non-linear time series, which decomposes a time series into a finite and often small number of Intrinsic Mode Functions (IMFs). The decomposition procedure is adaptive and data-driven. The IMFs are stationary which are more suitable for wavelet analysis. The merits of both the EMD and Wavelets are combined to produce an improved EMD-Wavelet {2.atic error extraction model. Thereafter, a method of the GPS baseline calculation based on the EMD-Wavelet {2.atic error mitigation model is suggested. The experimental results show that the proposed scheme dramatically improves the reliability of ambiguity resolution with a larger F-ratio and W- ratio indexes after {2.atic error elimination.

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GPS实时监测和预报电离层电子含量

天文学报 2004年第2期45卷 213-219页

作者：金双根 J.Wang 章红平朱文耀中国科学院上海天文台上海200030 school of surveying and {2. information systems University of New South WalesSydneyAustralia

GPS能高精度地实时监测电离层总电子含量(TEC)变化,对纠正单频GPS接收机电离层延迟和监测电离层活动及其所反映的太阳活动规律具有重要意义。上海地区GPS综合应用网的建立,为监测长江三角洲地区电离层变化提供了宝贵的资料,利用这些双频... 详细信息

GPS能高精度地实时监测电离层总电子含量(TEC)变化,对纠正单频GPS接收机电离层延迟和监测电离层活动及其所反映的太阳活动规律具有重要意义。上海地区GPS综合应用网的建立,为监测长江三角洲地区电离层变化提供了宝贵的资料,利用这些双频GPS接收机的连续观测资料,可近实时地监测和预报该地区电离层总电子含量,其内外符精度和外推预报30分钟的精度均优于0.4m。

关键词：天体测量学电离层电子含量 GPS 太阳活动规律

The Application Study about Ground-Based GPS Precipitable Water Vapor in Shijiazhuang and Qinhuangdao Region

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The Application Study about Ground-Based GPS Precipitable Wa...