LIU Meng,WANG Zhengtao.Downward Continuation Iterative Regularization Solution Based on Quasi⁃Optimal Regularization Factor Set[J].Geomatics and Information Science of Wuhan University,2025,50(12):2450-2459.
LIU Meng,WANG Zhengtao.Downward Continuation Iterative Regularization Solution Based on Quasi⁃Optimal Regularization Factor Set[J].Geomatics and Information Science of Wuhan University,2025,50(12):2450-2459.DOI:10.13203/j.whugis20230127
Downward Continuation Iterative Regularization Solution Based on Quasi⁃Optimal Regularization Factor Set
This paper addresses a critical limitation hindering the practical application of widely used iterative regularization methods
such as Tikhonov regularization and Landweber regularization. The lack of a clear strategy for optimally pairing iteration counts with regularization parameters.
Methods
2
The concept of a quasi-optimal regularization factor set is constructed. By analyzing the distribution of iteration counts and regularization parameters within these sets
a strategy for selecting the best regularization factor group is proposed. Furthermore
a formula is presented to determine the optimal regularization parameter corresponding to a given iteration count using the L-curve method.
Results
2
Analysis of the extension error and the variation within quasi-optimal factor sets reveals a significant correlation between optimal regularization parameters and iteration counts. When the iteration count exceeds 10
the extension solutions corresponding to different quasi-optimal factor sets become nearly identical. For sufficiently large iteration counts
any quasi-optimal factor set yields similar effects. Compared with the traditional Tikhonov regularization
the proposed iterative method based on the new selection strategy produces smoother extension solutions with smaller errors. However
in regions with sharp data variations
some high-frequency signals may be filtered out as noise
leading to no significant improvement in extension performance there.
Conclusions
2
The proposed iterative regularization algorithm incorporates the novel selection strategy
and generates smoother and more accurate extension solutions than the traditional Tikhonov method.The results demonstrate its reliability and practical utility.
关键词
Keywords
references
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