13 research outputs found
Lyapounov exponent of linear stochastic systems with large diffusion term
AbstractWe study the behaviour of the Lyapounov exponent of the solution of dXtAXt+δ∑i1rBkXt∘dWkt, as σ→∞. We obtain the exact behaviour in two cases for arbitrary dimensions, and in most cases for the two dimensional equation
The type II phase resetting curve is optimal for stochastic synchrony
The phase-resetting curve (PRC) describes the response of a neural oscillator
to small perturbations in membrane potential. Its usefulness for predicting the
dynamics of weakly coupled deterministic networks has been well characterized.
However, the inputs to real neurons may often be more accurately described as
barrages of synaptic noise. Effective connectivity between cells may thus arise
in the form of correlations between the noisy input streams. We use constrained
optimization and perturbation methods to prove that PRC shape determines
susceptibility to synchrony among otherwise uncoupled noise-driven neural
oscillators. PRCs can be placed into two general categories: Type I PRCs are
non-negative while Type II PRCs have a large negative region. Here we show that
oscillators with Type II PRCs receiving common noisy input sychronize more
readily than those with Type I PRCs.Comment: 10 pages, 4 figures, submitted to Physical Review
Nonlinear oscillator with parametric colored noise: some analytical results
The asymptotic behavior of a nonlinear oscillator subject to a multiplicative
Ornstein-Uhlenbeck noise is investigated. When the dynamics is expressed in
terms of energy-angle coordinates, it is observed that the angle is a fast
variable as compared to the energy. Thus, an effective stochastic dynamics for
the energy can be derived if the angular variable is averaged out. However, the
standard elimination procedure, performed earlier for a Gaussian white noise,
fails when the noise is colored because of correlations between the noise and
the fast angular variable. We develop here a specific averaging scheme that
retains these correlations. This allows us to calculate the probability
distribution function (P.D.F.) of the system and to derive the behavior of
physical observables in the long time limit
Lyapounov exponent of linear stochastic systems with large diffusion term
We study the behaviour of the Lyapounov exponent of the solution of , as [sigma]-->[infinity]. We obtain the exact behaviour in two cases for arbitrary dimensions, and in most cases for the two dimensional equation.
Lyapunov exponent and rotation number of two dimensional linear stochastic systems with small diffusion
SIGLETIB: RA 6154 (151) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman
Representation, positivity and expansion of Lyapunov exponents for linear stochastic systems
SIGLETIB: RA 6154 (127) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman
Asymptotic analysis of the Lyapunov exponent and rotation number of the random oscillator and applications
SIGLETIB: RA 6154 (134) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman