共查询到20条相似文献,搜索用时 15 毫秒
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W. D. Lambert 《Journal of Geodesy》1947,21(1):19-22
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针对线性最小二乘法处理非线性模型产生模型误差的问题,文章将高斯牛顿迭代法引入测角网坐标平差模型中,给出测角网坐标平差模型的高斯牛顿迭代法计算过程.考虑到非线性平差模型的参数估计值是有偏估计,结合Bootstrap重采样方法对参数估值进行改善,提出测角网坐标平差模型的Bootstrap参数估计方法,并给出详细的迭代流程图.针对等精度与不等精度角度观测数据,设计两个测角网案例.实验结果表明,测角网坐标平差模型的高斯牛顿迭代解法能够削弱线性近似带来的模型误差影响,其参数估值优于传统的线性近似方法;而测角网坐标平差模型的Bootstrap参数估计方法比高斯牛顿迭代解法在提高测角网坐标平差参数估值质量方面更加有效.实验证明将高斯牛顿迭代解法应用于测角网坐标平差模型的必要性与实用性,也证明将Bootstrap重采样参数估计方法与高斯牛顿迭代解法结合并用于测角网坐标平差的可行性与有效性. 相似文献
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A. D. N. Smith 《Journal of Geodesy》1967,41(4):469-475
Summary A method of adjusting intersecting chains of triangulation by direct elimination, using variation of coordinates, is given
which is suitable for a computer of modest storage capacity (about 4000–8000 words). The network is considered to be made
up of “nodes” (where two or more chains intersect) and “links” (which connect two nodes). The normal equations for the points
in each link are computed, the coefficients of the unknown coordinates of the associated nodes being treated as extra right
hand sides. These equations are then solved to express the coordinates of any link station in terms of the associated nodes.
The process is repeated for all links. The normal equations for the nodes are then set up and substitution made for all “link”
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The method is particularly powerful for the adjustment of a few, long, interconnected chains since the reduced normal equation
coefficients are then banded about the diagonal, the semi band width being a little greater than the largest number of unknowns
in the nodes along a single tie chain. For a computer of 7000 words capacity it is possible to solve for a band width of over
100 unknowns i.e. more than 50 stations. 相似文献
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一般情况下间接平差模型在平差前都给出参数的近似值,由于水准网观测值总能够由参数近似表示,在平差前可以不给出参数的近似值,直接进行平差,平差值为参数的估值。因此本文通过对间接平差模型的简化,基于MATLAB语言的丰富的数值计算功能和独特的GUI功能实现了任意网形的自由水准网、附合水准网经典平差系统的开发。用假设检验理论对平差结果从理论上进行可靠性分析,并用一个实例对系统的可靠性进行测试。试验结果表明,系统的平差结果是可靠的,系统可以对一等、二等、三等、四等以及等外任意网形的自由水准网、附合水准网进行经典平差,平差结果可靠。 相似文献
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针对不同等级测量控制网的联合平差,介绍一种不使用导数的解析方法,该方法一方面克服了传统平差中由于起算数据误差对低级网的精度影响,而使加密的精度逐次降低的缺点;另一方面,完全避免了导数的计算,大大减少了计算工作量。 相似文献
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