title: Radon time variations and deterministic chaos.
abstract: Radon concentrations were continuously measured outdoors, in the living room and in the basement at 10 min intervals for a month. Radon time series were analyzed by comparing algorithms to extract phase space dynamical information. The application of fractal methods enabled exploration of the chaotic nature of radon in atmosphere. The computed fractal dimensions, such as the Hurst exponent (H) from the rescaled range analysis, Lyapunov exponent (lambda) and attractor dimension, provided estimates of the degree of chaotic behavior. The obtained low values of the Hurst exponent (0 < H < 0.5) indicated anti-persistent behavior (non-random changes) of the time series, but the positive values of lambda pointed out the grate sensitivity on initial conditions and the deterministic chaos that appeared due to radon time variations. The calculated fractal dimensions of attractors indicated more influencing (meteorological) parameters on radon in the atmosphere.
authors.affiliation: Department of Physics, Faculty of Education, University of Osijek, P.O. Box 144, Osijek 31000, Croatia. planinic@pedos.hr
authors.forename: J
authors.initials: J
authors.lastname: Planinić
authors.forename: B
authors.initials: B
authors.lastname: Vuković
authors.forename: V
authors.initials: V
authors.lastname: Radolić
mesh_terms: D016902:Air Pollution, Indoor / Q000032:analysis*; D000465:Algorithms; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000032:analysis*; D008685:Meteorological Concepts; D017711:Nonlinear Dynamics; D011886:Radon / Q000032:analysis* / Q000737:chemistry; D015203:Reproducibility of Results; D013997:Time Factors
chemical_list: D004785:Environmental Pollutants; D011886:Radon