TY JOUR TI On the Use of a Complex Indicator of the Stability of Permutation Entropy of Time Series Fragments When Analyzing Infrasound Monitoring Signals of the Altai Republic KW infrasound monitoring KW time series KW permutation entropy KW complexity assessment KW stratospheric waveguide KW turning points JO Russian Journal of Earth Sciences AU Kudryavtsev, N.G. AU Frolov, I.N. AU Safonova, V.Y. PY 2023 IS 23 PB Geophysical Center of the Russian Academy of Sciences