Showing papers by "Kestutis Pyragas published in 2003"
01 Jan 2003
TL;DR: A brief review of experimental implementations, applications for theoretical models, and most important modifications of the method is presented in this paper, as well as an idea of using unstable degrees of freedom in a feedback loop to avoid a well known topological limitation.
Abstract: Time delayed-feedback control is an efficient method for stabilizing unstable periodic orbits of chaotic systems. The method is based on applying feedback proportional to the deviation of the current state of the system from its state one period in the past so that the control signal vanishes when the stabilization of the desired orbit is attained. A brief review of experimental implementations, applications for theoretical models, and most important modifications of the method is presented. Some recent results concerning the theory of the delayed feedback control as well as an idea of using unstable degrees of freedom in a feedback loop to avoid a well known topological limitation of the method are described in details.
3 citations
20 Aug 2003
TL;DR: An idea of using unstable degrees of freedom in a feedback loop to avoid a well known topological limitation of the method is described in details and is extended for the problem of adaptive stabilization of unknown steady states of dynamical systems.
Abstract: Time delayed-feedback control is an efficient method for stabilizing unstable periodic orbits of chaotic systems. The method is based on applying feedback proportional to the deviation of the current state of the system from its state one period in the past so that the control signal vanishes when the stabilization of the desired orbit is attained. A brief review of experimental implementations, applications for theoretical models, most important modifications as well as recent advancements in the theory of the method is presented. An idea of using unstable degrees of freedom in a feedback loop to avoid a well known topological limitation of the method is described in details. This idea is extended for the problem of adaptive stabilization of unknown steady states of dynamical systems.
3 citations
TL;DR: In this paper, the motion of test bodies in a Quasi-Newtonian potential is examined, and main attention is paid to the qualitative classification of all possible trajectories.
Abstract: Abstract The motion of test bodies in a Quasi-Newtonian potential is examined. Main attention is paid to the qualitative classification of all possible trajectories.
1 citations
TL;DR: In this article, the authors deal with the motion of test bodies in a Quasi-Newtonian potential for which the expressions corresponding to the effects of General Relativity are found.
Abstract: Abstract The paper deals with the motion of test bodies in a Quasi-Newtonian potential for which the expressions corresponding to the effects of General Relativity are found. It is impossible to choose the values of parameters of the potential which could be in a quantitative accordance with the effects predicted by General Relativity.
22 Jun 2003
TL;DR: In this paper, the authors proposed a method to suppress the intensity fluctuations of the laser, but all proposals are based on optical modifications to the laser cavity, which limits the technical applicability of such a kind of laser.
Abstract: Intracavity frequency doubled solid state laser that emit light in the visible spectral range have great potential for technical applications. These diode pumped lasers are compact, robust, efficient and have a higher output power compared to laser diodes. The intracavity frequency conversion by the optical nonlinear crystal is highly efficient but on the other hand destabilizes the dynamic of the laser under multimode operation. The resulting periodic or chaotic fluctuations of the output intensity are known as the green problem in literature and limits the technical applicability of such a kind of laser. However, it is possible to suppress the intensity fluctuations of the laser, but all proposals are based on optical modifications to the laser cavity.