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针对智能遥感卫星系统星上处理与端到端测绘应用的轻量化全球控制信息需求,本文提出了一种星载轻量化影像控制点数据制作方法。首先,在稀少/无地面控制数据条件下,通过国产高分辨率立体测绘卫星影像的区域网平差处理,生成全球影像控制点;其次,通过将影像控制点的局部影像描述至特征向量,设计星载影像控制点的轻量化表示模式,分析其存储性能和星上匹配应用策略;然后,采用哈希映射学习得到的哈希函数,将影像控制点特征向量转换至哈希码,实现星载影像控制点的深度轻量化处理;最后,采用多类型卫星影像数据,进行影像控制点提取、特征向量描述、深度轻量化处理以及匹配性能分析试验,验证了轻量化影像控制点星上匹配与应用可行性,得到了全球影像控制点轻量化处理能力分析结论。 相似文献
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韩惠军 《测绘与空间地理信息》2021,44(z1):222-224
在南极开展GNSS大地控制网建设,布设大地测量控制点标志,是开展测绘工作的基础,是丰富我国测绘地理信息成果的重要依据.受南极恶劣自然环境和南极科考工作时间短暂等不利因素的影响,以往布设在南极的GNSS大地测量控制点标志存在着风化、松动、移位等现象,严重影响了测量定位精度.2019年,针对以往布测大地控制点出现的问题,提出新的设计构思,并付诸实施. 相似文献
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地方坐标到2000国家大地坐标转换方法研究 总被引:2,自引:0,他引:2
我国自2008年7月1日起启用2000国家大地坐标系作为我国测绘生产和GIS系统建设新的坐标系。由于早期测绘生产没有采用统一的坐标系,坐标系统的不一致是GIS系统开发、数据建库和多源数据集成经常碰到的问题。回顾常用的坐标转换方法,并探讨数学模型转换方法的参数计算步骤与提高参数准确性的方法,利用厦门地方坐标系和2000国家大地坐标系下两套不同的公共控制点,计算转换参数,通过编写程序,完成了多种文件格式的测绘数据在两种坐标系之间的相互转换,取得了较好的效果。 相似文献
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《测绘与空间地理信息》2020,(6)
以高分二号国产卫星影像数据为实验对象,选取额敏县和乌恰县两个试验区,采用多种控制点布设方法,利用PCI遥感影像处理软件,对其纠正结果进行验证,提出满足1∶10 000测绘精度需求的控制点布设方案,为更高效率地完成1∶10 000基础测绘任务提供理论依据。 相似文献
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《International Journal of Digital Earth》2013,6(1):80-87
Abstract Cultures throughout the world are associating with the rivers. People depend upon the rivers and their tributaries for food, water, transport, and many other aspects of their daily lives. Unfortunately, human beings have not calculated the accurate lengths for the great rivers even today. The lengths of the rivers are very different in popular textbooks, magazines, atlases and encyclopedias, etc. To accurately determine the lengths of the principal rivers of the world, the combination of satellite image analysis and field investigations to the source regions is proposed in this paper. The lengths of the Nile, Amazon, Yangtze, Mississippi, Yellow, Ob, Yenisey, Amur, Congo and Mekong, with lengths over or close to 5000 km, were calculated using the proposed method. The results may represent the most reliable and accurate lengths of the principal rivers of the world that are currently achievable. 相似文献
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软科学这一术语是70年代在国外提出的.然而30多年以来,它在国外不仅未得到普遍的承认,而且对软科学的定义也还未能达成大体上一致的共识.而在改革开放后的中国,出于决策科学化和民主化的需要,经过一些领导人的提倡和支持,特别是通过1986年召开的软科学座谈会及1994年召开的全国软科学工作会议,软科学事业得到了蓬勃的发展.据初步统计,截止1998年底全国共有软科学研究机构1224个,研究人员32655人,初步形成了一支较为强大的研究队伍,并取得了数百项覆盖多个领域的研究成果,为支持各级各类的决策发挥了一定的作用. 相似文献
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Tobias Nilsson Benedikt Soja Kyriakos Balidakis Maria Karbon Robert Heinkelmann Zhiguo Deng Harald Schuh 《Journal of Geodesy》2017,91(7):857-866
The very long baseline interferometry (VLBI) Intensive sessions are typically 1-h and single-baseline VLBI sessions, specifically designed to yield low-latency estimates of UT1-UTC. In this work, we investigate what accuracy is obtained from these sessions and how it can be improved. In particular, we study the modeling of the troposphere in the data analysis. The impact of including external information on the zenith wet delays (ZWD) and tropospheric gradients from GPS or numerical weather prediction models is studied. Additionally, we test estimating tropospheric gradients in the data analysis, which is normally not done. To evaluate the results, we compared the UT1-UTC values from the Intensives to those from simultaneous 24-h VLBI session. Furthermore, we calculated length of day (LOD) estimates using the UT1-UTC values from consecutive Intensives and compared these to the LOD estimated by GPS. We find that there is not much benefit in using external ZWD; however, including external information on the gradients improves the agreement with the reference data. If gradients are estimated in the data analysis, and appropriate constraints are applied, the WRMS difference w.r.t. UT1-UTC from 24-h sessions is reduced by 5% and the WRMS difference w.r.t. the LOD from GPS by up to 12%. The best agreement between Intensives and the reference time series is obtained when using both external gradients from GPS and additionally estimating gradients in the data analysis. 相似文献
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In this letter, we are trying to resolve the electromagnetic problem for the movements of the superconducting particles of the protoplanetary cloud in the magnetic field of Saturn. The force of levitation (Meissner-Ochsenfeld phenomenon) is introduced to the field of planetary science for the first time. It is shown from our theoretical analysis that rings of Saturn might have a superconducting origin, and rings might levitate within magnetic equator plane of the planet. 相似文献
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根据残差二次型次小与最小之差进行整周模糊度确认的关键是差值的分布,只有得到了合理的差值分布才可确定合理的界值.文中基于原有的两种方法及这两种方法的不足,从理论上导出了满足条件的差值分布,并作了一定的说明. 相似文献