Annual variability in a conceptual climate model: Snapshot attractors, hysteresis in extreme events, and climate sensitivity

Tamás Bódai and Tamás Tél

Within Lorenz’s model of global atmospheric circulation (L84), the climate is sensitive if under slightly different conditions, the climate snapshot attractor takes substantially different shapes. This paper focuses on extreme event return time statistics, climate sensitivity, and overall variability in view of snapshot attractors.

Chaos 22 , 023110 (2012)

Chimeras in random non-complete networks of phase oscillators

Carlo R. Laing, Karthikeyan Rajendran, and Ioannis G. Kevrekidis

Chimera states are known to occur in networks of identical phase oscillators and are characterised by some fraction of the oscillators being synchronised, while the remainder are asynchronous. Here, we systematically investigate these systems for what is arguably the simplest network that shows chimera states, considering two different systematic ways of perturbing an all-to-all connected network.

Chaos 22 , 013132 (2012)

The impact of awareness on epidemic spreading in networks

Qingchu Wu, Xinchu Fu, Michael Small, and Xin-Jian Xu

The authors explore the impact of awareness on epidemic spreading through a population represented by a scale-free network. Using a network mean-field approach, a mathematical model for epidemic spreading with awareness reactions is proposed and analyzed. Theoretical analysis and simulation shows that global awareness cannot decrease the likelihood of an epidemic outbreak while both local awareness and contact awareness can.

Chaos 22, 013101 (2012)

Propagation of spiking regularity and double coherence resonance in feedforward networks

Cong Men, Jiang Wang, Ying-Mei Qin, Bin Deng, Kai-Ming Tsang, and Wai-Lok Chan

Multi-layer feedforward networks (FFNs) are related to functional groups of neurons where information is transmitted from one group to the next. Since much information in neural systems is carried by interspike intervals time series, the propagation of spike regularity in the brain is an essential problem. This paper investigates the effects of noise on the propagation of spike regularity in FFN.

Chaos 22, 013104 (2012)

Eikonal-based initiation of fibrillatory activity in thin-walled cardiac propagation models

Antoine Herlin and Vincent Jacquemet

The authors have developed a new computational framework to control the complexity of simulated atrial fibrillation (AF) dynamics. The complexity of the dynamics can be controlled in terms of the number and locations of phase singularities. As a result, a database of simulated AF episodes with varying degrees of complexity can be created.

Chaos 21 , 043136 (2011)

Exponential cluster synchronization of impulsive delayed genetic oscillators with external disturbances

Wenbing Zhang, Yang Tang, Jian-an Fang, and Wu Zhu

The authors investigate the cluster synchronization of delayed impulsive genetic oscillators with communication delay and external disturbance and derive some new cluster synchronization criteria for coupled impulsive genetic oscillators with an attenuation level based on the Kronecker product. The derived results are related to the impulsive strengths, coupling structure, time delay, and the decay rate of system.

Chaos 21 , 043137 (2011)

Energetics of stochastic resonance

Peter Jung and Fabio Marchesoni

The authors discuss the motion of a Brownian particle in a double-well potential driven by a periodic force in terms of energies delivered by the periodic and the noise forces and energy dissipated into the viscous environment. The authors show that, while the power delivered by the periodic force to the Brownian particle is controlled by the strength of the noise, the power delivered by the noise itself is independent of the amplitude and frequency of the periodic force.

Chaos 21, 047516 (2011)

Sensory coding in oscillatory electroreceptors of paddlefish

Alexander B. Neiman and David F. Russell

The authors characterized the linear and nonlinear response properties of Lorenzinian ampullary electroreceptors (ERs) of live paddlefish, and their encoding of various kinds of time-varying stimuli, ranging from artificial broad-band Gaussian noise to natural waveforms recorded from zooplankton prey.

Chaos 21, 047505 (2011)
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Effects of thermal gradients on the intensity of vortices generated in a cylindrical annulus

M. C. Navarro and H. Herrero

The authors have studied the influence of temperature gradients on the intensity of dust-devil-like vertical vortices in a cylindrical annulus. Increasing the temperature gradients intensifies the strength of the vortical structures developed while decreasing the gradients leads to weaker vortices or, in some cases, can even make them disappear.

Chaos 21, 043132 (2011)

Applying snapback repellers in resource budget models

Shu-Ming Chang and Hsun-Hui Chen

This work presents mathematical viewpoints and numerical analysis on Satake’s generalized resource budget model to rigorously prove that the generalized resource budget model is chaotic in Devaney’s sense by using the snapback repeller theory and the topological entropy theory.

 

Chaos 21, 043126 (2011)