Biomedical subjects

K Josić

Publications and source records attributed to K Josić.

3 recordsLinked to original sources

PubMed2004

Irrational phase synchronization.

We study the occurrence of physically observable phase locked states between chaotic oscillators and rotors in which the frequencies of the coupled systems are irrationally related. For two chaotic oscillators, the phenomenon occurs as a result of a coupling term which breaks the 2 pi invariance in the phase equations. In the case of rotors, a coupling term in the angular velocities results in very long times during which the coupled systems exhibit alternatively irrational phase synchronization and random phase diffusion. The range of parameters for which the phenomenon occurs contains an open set, and is thus physically observable.

Journal Article↗

PubMed2001

Phase synchronization of chaotic systems with small phase diffusion.

The geometric theory of phase locking between periodic oscillators is extended to phase coherent chaotic systems. This approach explains the qualitative features of phase locked chaotic systems and provides an analytical tool for a quantitative description of the phase locked states. Moreover, this geometric viewpoint allows us to identify obstructions to phase locking even in systems with negligible phase diffusion, and to provide sufficient conditions for phase locking to occur. We apply these techniques to the Rössler system and a phase coherent electronic circuit and find that numerical results and experiments agree well with theoretical predictions.

Journal Article↗

PubMed1997

Local bifurcations in the symmetric model of selection with fertility differences.

The analysis of difference equations in population dynamics is frequently confined to the calculation of fixed points and the determination of their stability. In general it is not possible to deduce much about the global behavior of the system from such information. This paper presents a study of the bifurcations of fixed points in the symmetric model of selection with fertility differences. Equivalent methods can be applied to other continuous and discrete models to study the dynamics in the vicinity of fixed points in a systemic way and as a first step in an analysis of the global dynamics.

Animals↗