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本文通过模拟试验全面分析了摄影测量与大地测量观测值联合平差的质量特点(精度,可靠性,可区分性),据此为联合网的设计提出了具体方案。所得结论对于联合平差的实际应用以及联合平差的智能化实现都有参考价值。 相似文献
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本文讨论了在摄影测量单模型平差中,利用大地观测数据及外方位元素观测值与摄影测量进行联合平差时对平差结果的影响:距离和高差分别对平面精度和高程度都有明显的改善,角度观测值对平面和高程精度都有所改善;精度较高的像片外方位元素可使无控制点条件下的平差达到或接近仅有四个控制点的平差精度;各种观测值联合平差比单独平差的精度有不同程度的提高。 相似文献
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武汉测绘科技大学联合平差程序系统WuCAPS能进行摄影与非摄影量观测值的联合平差，它可容许大地测量观测值、GPS获取的摄影站坐标、惯性导航系统获取的摄影机姿态等数据。本文介绍了该程序系统的主要算法，包括数据结构、未知数的排序与求解、协因数矩阵的计算、可靠性矩阵的计算。这些算法都已经过计算验证并已用于生产。 相似文献
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全站仪设站测量的人工整平是目前既有线铁路天窗期外业轨道测量效率高低的重要影响因素。为了实现全站仪的不整平后方交会测量,本文首先提出了基于斜距观测值的三维后方交会测量平差模型,经过实验验证发现,基于单一斜距观测值的后方交会测量平差模型存在一定缺陷。之后对上述平差模型进行了两种不同方法的改进,分别是基于斜距观测值的后方交会测量迭代平差和斜距观测值与竖盘读数观测值逐次平差。经实验数据验证与分析,改进后的两种平差模型均可以计算出较为可靠的后方交会点三维坐标与设站精度,说明改进模型具有可行性,同时提出了该方向需要继续深入研究的问题。 相似文献
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王有年 《武汉大学学报(信息科学版)》1987,(2)
在深入研究了联合平差的基本理论后,作者在VAX-11/750小型计算机上建立了一个主要适合于近景摄影测量的联合平差程序系统,它具有粗差的自动定位、系统误差补偿、进行多种观测值的同时平差等多种现代先进的摄影测量平差系统所应具备的功能。本文简要介绍该联合平差程序系统的有关基本理论、基本功能、基本结构及处理有关问题的基本方法,并举例说明联合平差及该程序系统在近景摄影测量中的应用。 相似文献
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大地测量函数模型与随机模型是大地测量数据处理必须要涉及的模型。经过60年不懈努力,中国学者根据大地测量应用实际,构建和改进了许多函数模型,如广义测量平差模型、等价观测方程、非线性平差模型等;在方差分量估计和误差检验方面做了大量创新性工作,如基于Bayes估计的方差分量估计、拟准误差检验等,丰富了测量平差理论与方法。这一部分重点介绍建国60年来中国学者在大地测量数据处理函数模型、随机模型和误差检验方面所取得的成就。 相似文献
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本文主要研究了GPS变形监测中垂直位移的问题。通过对误差分析,建立GPS大地高高差平差模型,以便提高GPS变形监测在垂直位移方向上的精度。从而真正的达到GPS三维监测。 相似文献
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韩国和马来西亚建立本国三维地心大地坐标系统的进展 总被引：1，自引：0，他引：1
介绍了韩国大地坐标系统的沿革 ,阐述了近年来韩国建立本国三维地心坐标系的工作和进展。为了对比韩国 ,简约介绍了马来西亚等国在这方面的新进展 相似文献
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Ming H. Xu Robert Heinkelmann James M. Anderson Julian Mora-Diaz Maria Karbon Harald Schuh Guang L. Wang 《Journal of Geodesy》2017,91(7):767-781
Closure quantities measured by very-long-baseline interferometry (VLBI) observations are independent of instrumental and propagation instabilities and antenna gain factors, but are sensitive to source structure. A new method is proposed to calculate a structure index based on the median values of closure quantities rather than the brightness distribution of a source. The results are comparable to structure indices based on imaging observations at other epochs and demonstrate the flexibility of deriving structure indices from exactly the same observations as used for geodetic analysis and without imaging analysis. A three-component model for the structure of source 3C371 is developed by model-fitting closure phases. It provides a real case of tracing how the structure effect identified by closure phases in the same observations as the delay observables affects the geodetic analysis, and investigating which geodetic parameters are corrupted to what extent by the structure effect. Using the resulting structure correction based on the three-component model of source 3C371, two solutions, with and without correcting the structure effect, are made. With corrections, the overall rms of this source is reduced by 1 ps, and the impacts of the structure effect introduced by this single source are up to 1.4 mm on station positions and up to 4.4 microarcseconds on Earth orientation parameters. This study is considered as a starting point for handling the source structure effect on geodetic VLBI from geodetic sessions themselves. 相似文献
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Kamil Eren 《Journal of Geodesy》1984,58(2):137-150
In earthquake prediction studies geodetic surveys play a very significant role. For this purpose, in Turkey, three micro geodetic
networks have been established across the North Anatolian Fault. Of these, the Ismetpa§a Network is the subject of this paper.
From the observations in combined triangulation—trilateration mode in 1972 and 1982 the horizontal movements and strain components
were determined. Afterwards the parameters of the best fitting deformation model were computed and analyzed. The results show
that the Anatolian plate has about a 1 cm/year westward motion, and there exists considerable strain accumulation in the area. 相似文献
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大地测量反演中的大部分问题都是非线性问题,如何解算和评价非线性反演问题是大地测量反演研究的重点和难点。本文给出了大地测量半线性反演的基本理论,针对实际的观测数据采样并非等距均匀,提出了基于三次样条的大地测量半线性反演方法,该方法综合了当前非线性反演受初始模型受制约较小和线性反演理论具有完善评价体系的优点。 相似文献
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Hermann Drewes 《Journal of Geodesy》1982,56(1):70-79
Modern techniques of precise geodetic positioning are capable of monitoring global tectonic movements. We can avoid the tremendous
effort of observing those point motions at every place on the earth, if we accept the model of rigid tectonic plates, which
allows us to extrapolate from discrete point observations to the appertaining plates. The target of describing plate kinematics
is the determination of its kinematic parameters, which are the coordinates of the rotation pole and the rotational velocity
of each tectonic plate.
A mathematical model is presented, which is capable of including geodetic observations (point coordinate shifts, distance
changes) as well as geophysical quantities (sea floor spreading rates, earthquake slip vectors). The parameter estimation
procedure is derived and demonstrated in simulated examples. Finally a global geodetic network for space techniques is designed,
which provides an optimum parameter estimation. 相似文献
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Modern geodetic positioning techniques likeVLBI, SLR, andGPS can be used for plate tectonic studies. A very simple model considers a number of rigid plates rotating individually with
a constant rotation rate.
An equally simple mathematical model, extended to deformable plates, is presented, based on vector calculus, which relates
both absolute and relative point positioning observations to the plate rotation and deformation parameters (rotation rate,
direction of rotation vector, deformation rate and direction of deformation center) in a consistent and elementary way. The
determination of these plate parameters from various geodetic positioning observations is outlined. 相似文献
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组合GPS和VLBI数据建立板块运动模型 总被引：6，自引：0，他引：6
利用GPS和VLBI的组合数据,解算了北美、欧亚、太平洋等12板块之间的相对运动欧拉矢量,得到了实测的板块运动模型GVM1。与地学模型(NUVEL1A)的比较指出,GVM1大体上与地学模型一致;EURANOAM的极位置与NUVEL1A的相应极比较接近,旋转速率略微偏大;澳大利亚板块在最近几年内是稳定的;太平洋板块与其他板块对的极位置与地学模型较为接近,这表明多种技术的组合数据提高了板块运动模型建立的精确性和可靠性。 相似文献
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组合VLBI和SLR数据估计的全球板块运动参数 总被引：4，自引：0，他引：4
本文组合应用ＶＬＢＩ和ＳＬＲ数据导出了一个完全基于空间技术实测数据的现时板块运动模型，称为ＳＧＰＭＭ１。ＳＧＰＭＭ１与地学板块运动模型ＮＵＶＥＬ－１的比较指出：空间大地测量数据估计的板块运动总体上与地学估计值一致。经过地磁极倒转时间尺度修正，并考虑到冰斯后地壳回弹的影响，空间大地测量数据估计的北美，欧亚和澳大利亚板块之间的相对运动速率与地学估计值有极好的一致，但太平洋板块相对于北美、欧亚和澳大利亚 相似文献