4 research outputs found
Effective synchronization of a class of Chua's chaotic systems using an exponential feedback coupling
In this work a robust exponential function based controller is designed to
synchronize effectively a given class of Chua's chaotic systems. The stability
of the drive-response systems framework is proved through the Lyapunov
stability theory. Computer simulations are given to illustrate and verify the
method.Comment: 12 pages, 18 figure
Finite-time synchronization of tunnel diode based chaotic oscillators
This paper addresses the problem of finite-time synchronization of tunnel
diode based chaotic oscillators. After a brief investigation of its chaotic
dynamics, we propose an active adaptive feedback coupling which accomplishes
the synchronization of tunnel diode based chaotic systems with and without the
presence of delay(s), basing ourselves on Lyapunov and on Krasovskii-Lyapunov
stability theories. This feedback coupling could be applied to many other
chaotic systems. A finite horizon can be arbitrarily established by ensuring
that chaos synchronization is achieved at a pre-established time. An advantage
of the proposed feedback coupling is that it is simple and easy to implement.
Both mathematical investigations and numerical simulatioComment: 11 pages, 43 figure
Phase synchronization of bursting neural networks with electrical and delayed dynamic chemical couplings
Diffusive electrical connections in neuronal networks are instantaneous, while excitatory
or inhibitory couplings through chemical synapses contain a transmission time-delay.
Moreover, chemical synapses are nonlinear dynamical systems whose behavior can be
described by nonlinear differential equations. In this work, neuronal networks with
diffusive electrical couplings and time-delayed dynamic chemical couplings are considered.
We investigate the effects of distributed time delays on phase synchronization of bursting
neurons. We observe that in both excitatory and Inhibitory chemical connections, the phase
synchronization might be enhanced when time-delay is taken into account. This distributed
time delay can induce a variety of phase-coherent dynamical behaviors. We also study the
collective dynamics of network of bursting neurons. The network model presents the
so-called Small-World property, encompassing neurons whose dynamics have two time scales
(fast and slow time scales). The neuron parameters in such Small-World network, are
supposed to be slightly different such that, there may be synchronization of the bursting
(slow) activity if the coupling strengths are large enough. Bounds for the critical
coupling strengths to obtain burst synchronization in terms of the network structure are
given. Our studies show that the network synchronizability is improved, as its
heterogeneity is reduced. The roles of synaptic parameters, more precisely those of the
coupling strengths and the network size are also investigated