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Real-time fractal signal processing in the time domain

Listed author(s):
  • Hartmann, András
  • Mukli, Péter
  • Nagy, Zoltán
  • Kocsis, László
  • Hermán, Péter
  • Eke, András
Registered author(s):

    Fractal analysis has proven useful for the quantitative characterization of complex time series by scale-free statistical measures in various applications. The analysis has commonly been done offline with the signal being resident in memory in full length, and the processing carried out in several distinct passes. However, in many relevant applications, such as monitoring or forecasting, algorithms are needed to capture changes in the fractal measure real-time. Here we introduce real-time variants of the Detrended Fluctuation Analysis (DFA) and the closely related Signal Summation Conversion (SSC) methods, which are suitable to estimate the fractal exponent in one pass. Compared to offline algorithms, the precision is the same, the memory requirement is significantly lower, and the execution time depends on the same factors but with different rates. Our tests show that dynamic changes in the fractal parameter can be efficiently detected. We demonstrate the applicability of our real-time methods on signals of cerebral hemodynamics acquired during open-heart surgery.

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    Article provided by Elsevier in its journal Physica A: Statistical Mechanics and its Applications.

    Volume (Year): 392 (2013)
    Issue (Month): 1 ()
    Pages: 89-102

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    Handle: RePEc:eee:phsmap:v:392:y:2013:i:1:p:89-102
    DOI: 10.1016/j.physa.2012.08.002
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    9. Staudacher, M. & Telser, S. & Amann, A. & Hinterhuber, H. & Ritsch-Marte, M., 2005. "A new method for change-point detection developed for on-line analysis of the heart beat variability during sleep," Physica A: Statistical Mechanics and its Applications, Elsevier, vol. 349(3), pages 582-596.
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