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A new approach to describe and analysis the structural and forming characteristics in time domain of signals are presented here. This approach is based on the decomposition of initial process into individual components, which are characteristic of the structure of its curving, and corresponding calculations for different configuration, energy and information parameters.

А number of novel possibilities of generation and amplification of spatially coherent radiation using planar Bragg structures is reviewed. In particular, we study schemes of Cherenkov oscillators with 2D distributed feedback, and a possibility of using this mechanism for synchronization of radiation of active laser media. Electronic amplifiers based on planar Bragg waveguides are discussed as well.

The possibility of usage of klystron active oscillator with delayed feedback as a source of chaotic radio pulses was explored. Experimental results of chaotic radio pulses producing in multicavity active oscillator with delayed feedback by means of the influence of radio-frequency pulses, delivered in the feedback line are presented. Experimental results showed that the initiation of chaotic radio-frequency pulses is possible in the whole zone of amplitude curve (gain characteristic) of autonomous klystron active oscillator.

Features of nonlinear dynamics of backward-wave tube in the presence of such factors as energy dissipation at wave transmission, field of space charge, wave reflection at the system edges are analyzed. Dynamics of the backward-wave tube with coupled systems including multi-stability connected with possibility of beam interaction with low or fast normal wave in the coupled transmission lines is discussed.

The problem of the interaction of two identical weakly coupled van der Pol – Duffing oscillations has been considered. The method of Poincare – Dulak normal forms has been used for its solution. All automodel periodic solutions have been found analytically. The problem of local bifurcations of these periodic solutions has been studied.

Numerical calculations of structures, Infrared and Raman vibrational spectra of small water clusters are performed by solution of the molecular SchrÄ odinger equation in the X 3LYP/aug-cc-pVQZ theory. Spectral features and evolution of hydrogen bond properties in clusters with their size growth are discussed. Obtained results may be used in molecular dynamics simulations of water.

In this paper the influence of noise in system of identical coupled logistic maps with two types of coupling – dissipative and inertial – is discussed.   The corresponding renormalization group analysis is presented. Scaling property in the presence of noise is considered, and necessary illustrations in «numerical experiment style» are given.

The work is devoted to investigation of complex dynamics in the model of two interacting systems with phase and delay control. Stability conditions of synchronous regime are determined. The processes of excitement of nonsynchronous regimes and transitions between them are considered. Scenarios of development of nonsynchronous regimes under variation of the systems parameters are determined. Routes to chaotic behavior of the model are discussed. Results are presented in the form of one-parameter bifurcation diagrams and phase portraits of the model attractors.

We investigated the influence of external noise on the critical behavior typical to nonidentical coupled systems with period-doubling. We obtained the numerical value of the scaling factor for noise amplitude by means of the renormalization group analysis. Also we demonstrated the selfsimilar structure of the parameter plane near the critical point in the model system of two noisy driven coupled logistic maps.

In the present paper we analyze the influence of white and colored noise on chaotic selfsustained oscillations in the regime of spiral attractor. We study characteristics of instantaneous phase and spectra of noisy chaotic oscillations. The phenomenon of chaos synchronization by external narrow-band noise has been estimated. Synchronization phenomena under the influence of narrow-band noise signals with equal spectra and different probability densities are compared.