摘要
用小波分解下各尺度上的能量信息熵计算了Lorenz系统退化数据的小波熵序列,计算结果表明退化前后两小波熵序列所蕴含的动力学特征基本一致;进一步讨论了窗口宽度对小波熵序列的影响,发现同一序号点的小波熵值退化增量随窗口宽度增大保持稳定,表明小波熵序列具有较强的抗退化能力,能够从退化数据中挖掘出非线性系统的动力学特征,为运用退化数据揭示复杂非线性系统的动力学特征提供了一种有效的方法;最后将该方法应用于南极中山站地磁场数据,获得了地磁场变化强度的演变特征,地磁场的磁暴区、平静区、稳定变化区在小波熵序列的波形中具有非常明显的特征.
The Lorenz system＇s time series and its degradated time series were decomposed by wavelet transform and turned into various components of different scales, then all components＇ energy and the signal＇s information entropy were calculated under a series of sliding windows, obtained the dynamic wavelet entropy-wavelet entropy sequence, the calculation results show that the two wavelet entropy sequences contain the very consistent dynamics characteristic; Further more we discussed the influence of window width on the wavelet entropy sequence, and found that the degradated incremental of the wavelet entropy value was stable along with the increasing window width, show that the wavelet entropy sequence has strong resistance to degradation, which could dig out the dynamic characteristics of the complex system from the degradated data, it was provided a effective method for using the degradated data to reveal the dynamic characteristics of the complex system; Finally, the method was applied to the geomagnetic data of the South Pole ZhongShan station, acquired the evolution characteristics of the geomagnetic variational intensity, in which the evolution characteristics of storms area, calm area, stable change area had the very obvious characteristics in the wavelet entropy sequence.
出处
《数值计算与计算机应用》
CSCD
2012年第3期198-206,共9页
Journal on Numerical Methods and Computer Applications
基金
江西省自然科学基金(20114BAB211015)
吉安市科技局2011年度指导性科技计划项目
