基于正交最小二乘多面函数构建局域海洋地磁场模型研究

摘要

针对多面函数拟合局域海洋地磁场模型中质量控制和节点选择问题,提出使用抗差估计与正交最小二乘原理相结合的方法.在质量控制过程中,将局部有显著起伏的采样点视为异常观测值,采用抗差估计减弱异常值点的不利影响.在节点选择中,使用基于正交最小二乘原则判断节点的贡献效力大小,按照此原则自适应地选择节点.结果表明,基于正交最小二乘原理的多面函数法的精度和稳定性更好,更适于构建局域海洋地磁场模型.%Aim at the problem of quality control and node choice in modeling local marine geomagnetic field based on multi-surface function, a fitting method with combining robust trend surface and orthogonal least squares is proposed. In order to control the influence of some outstanding points to surface fitting, a robust fitting of the trend surface by using an equivalent weight is adopted and the adaptive node choosing method is proposed based on the effect of every node on the curve fitting calculated by using the orthogonal least squares as well. The results show that this method is more effective in accuracy and stability than normal method.