中文摘要：

以无缝仿射基准变换为例，研究了无缝基准转换模型的方差分量估计理论，导出无缝基准变换过程中两套坐标的方差分量估计公式。通过模拟试验分析表明，采用方差分量估计方法能正确地恢复出客观体现两套坐标误差的方差值，从而有效提高无缝基准转换精度。

英文摘要：

With the seamless affine transformation as an instance, the variance component estimation （VCE） theory is studied in the seamless datum transformation. The VCE formula of the seamless transformation model is derived. The results from the simulation experiments show that the VCE can correctly recover the objectwe variance components of coordinates in two datums. As a result, the accuracy of seamless transformation can be improved.