Comparison of spectral and entropic measures for surface electromyography time series: a pilot study.

  title={Comparison of spectral and entropic measures for surface electromyography time series: a pilot study.},
  author={Paul S. Sung and Ulrich Zurcher and Miron Kaufman},
  journal={Journal of rehabilitation research and development},
  volume={44 4},
In a previous study, we reported that the mean square displacement calculated from the surface electromyography (sEMG) signal of low back muscles exhibits a plateaulike behavior for intermediate times 20 ms < t < 400 ms. This property indicates the existence of correlations in the signal for times much longer than the inverse of the median frequency (MF), which is calculated from the power spectrum 1/ = 1/(100 Hz) = 10 ms, where is the MF. This result suggests the use of methods from nonlinear… 

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