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精密工程测量控制网的建立方法 总被引:2,自引:0,他引:2
详细介绍了精密工程测量控制网的布设、控制测量的实施和数据处理的通用作业方法,并结合上海光源精密工程控制网的建立,进一步说明了通用作业方法的可行性,对同类高精度工程控制网的建立具有一定的指导作用。 相似文献
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通过一个施工控制网施测实例,简述了现代工程测量中高精度施工控制网布设的有效方法,以求对任意等级的施工控制网的建立提供一些措施。 相似文献
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针对传统GNSS控制网中需要多人多台设备同步观测的缺点,提出了利用CORS来进行单点测量的模式,并利用Bland-Altman对两种测量模式进行检验。采用CORS单点测量模式代替网模式,较好地解决了在网观测中多台设备同步观测的缺点,根据Bland-Altman检验,测量结果能达到E级网测量结果。基于CORS单点测量模式的实践表明,本文所提的测量模式不仅能满足区域控制网的要求,也能较好地提高高精度控制测量的效率,研究结果是对高精度控制测量方法的补充,可以应用于农村集体土地登记发证等项目中。 相似文献
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内插法布设无碴轨道铺轨控制测量网方法 总被引:4,自引:0,他引:4
针对勘测设计阶段测量精度要求较低,而无碴轨道施工测量精度要求很高的情况。提出在勘测设计控制网中内插高精度施工控制网的方法。导出保持线路控制网两端切线(直线)实地位置不变,布设高精度施工控制网的办法。 相似文献
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简述了GPS测量的基本原理以及在北京某地铁线控制测量中的应用情况,为GPS技术在地铁控制测量中的应用提供了借鉴。通过分析北京某地铁线GPS控制网的布设、观测及数据处理,对GPS技术在高精度控制网测量中的应用提出了几点建议。 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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本文从理论上推导了工程摄影测量中交向摄影方式各元素影响物点坐标精度的严密公式,并根据理论分析的结果,采用先进的数码相机和量测相机进行了一定的试验,在仔细分析试验结果的基础上,找出了工程摄影测量中交向摄影最佳的交向角、摄影基线、摄影距离和摄影比例尺等参数,对物点坐标总精度的影响规律。实际作业中,要使最佳交向摄影方式获得最理想的点位精度,所总结出的结论是可行的。 相似文献