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Natural Time Analysis: The New View of Time : Precursory Seismic Electric Signals, Earthquakes and other Complex Time Series
Part I Seismic Electric Signals.- 1. Introduction to Seismic Electric Signals-V.- Part II.- 2. Natural Time. Background-F.- 3. Entropy in Natural Time-E.- Part III Natural Time Applications.- 4.Expand
Long-range correlations in the electric signals that precede rupture.
The Smoluchowski-Chapman-Kolmogorov functional equation is applied to the electric signals that precede rupture. The results suggest a non-Markovian character of the analyzed data. The rescaled rangeExpand
Natural time analysis of critical phenomena
It is shown that κ1 becomes equal to 0.070 at the critical state for a variety of dynamical systems, including criticality models such as 2D Ising and the Bak–Tang–Wiesenfeld sandpile, which is the standard example of self-organized criticality. Expand
Entropy of seismic electric signals: analysis in natural time under time reversal.
Electric signals recorded at the Earth's surface with amplitudes appreciably larger than those hitherto reported are probably seismic electric signal activities (critical dynamics) and the entropy fluctuations are found to increase upon approaching bursting, reminiscent of the behavior identifying sudden cardiac death individuals when analyzing their electrocardiograms. Expand
Long-range correlations in the electric signals that precede rupture: further investigations.
The correlations within the time series of the seismic electric signal (SES) activities have been studied and certain power spectrum characteristics seem to distinguish SES activities from "artificial" (man-made) electric noises. Expand
Investigation of seismicity after the initiation of a Seismic Electric Signal activity until the main shock.
Analysis of the time series of small earthquakes, the concept of natural time chi was used and the results revealed that the approach to criticality itself can be manifested by the probability density function (PDF) of kappa(1) calculated over an appropriate statistical ensemble. Expand
Fluctuations, under time reversal, of the natural time and the entropy distinguish similar looking electric signals of different dynamics
We show that the scale dependence of the fluctuations of the natural time itself under time reversal provides a useful tool for the discrimination of seismic electric signals (critical dynamics) fromExpand
Minimum of the order parameter fluctuations of seismicity before major earthquakes in Japan
It is found that the fluctuations of the order parameter of seismicity exhibit distinct minima a few months before all of the shallow earthquakes of magnitude 7.6 or larger that occurred during this 27-y period in the Japanese area. Expand
Scale-specific order parameter fluctuations of seismicity in natural time before mainshocks
We have previously shown that the probability distribution of the order parameter κ1 of seismicity in natural time turns to be bimodal when approaching a mainshock. This reflects that, for variousExpand
Nonextensivity and natural time: The case of seismicity.
Natural time analysis reveals that the nonextensivity parameter q, in contrast to some published claims, cannot be considered as a measure of temporal organization, but the Tsallis formulation does achieve a satisfactory description of real seismic data for Japan for q=1.66 when supplemented by long-range temporal correlations. Expand