ISSN 1817-3020 (Print)
ISSN 2542-193X (Online)

Научный отдел


По имеющимся представлениям изменения волновой функции квантовых частиц вполне исчерпываются непрерывной детерминированной эволюцией согласно уравнению Шредингера и мгновенной вероятностной редукцией к одной из собственных функций оператора измеряемой величины. В данной статье предложена динамическая модель, согласно которой случившийся переход в собственное состояние в общем случае про-исходит за некоторый короткий промежуток времени.

Optical biomedical diagnostics

This paper presents an overview on optical biomedical diagnostics. It discusses briefly the history of the problem. The main attention is paid to description of the modern methods of optical medical diagnostics based on spectrophotometry, fluorescence, Doppler spectroscopy, elastic, quasi-elastic and Raman scattering spectroscopies, as well as optothermal and optoacoustic effects.

Anishchenko-astakhov self-sustained oscillator as one of the basic models of deterministic chaos

In the present review the conditions of appearing chaotic self sustained oscillations are formulated and a radio-technical scheme of a generator realizing these conditions is given. The equations of Anishchenko-Astakhov's generator are derived and analyzed. A special attention is paid to the interrelation between the generator's equations and Theodorchik and Van der Pole classical models.

Nonstationary excitation of open structures

The nonstationary theory of excitation for open resonators, waveguides and waveguide transformers has been developed. The open structures which are contained dielectric, magnetic and metallic bodies have been considered.

Classical analysis of recombination of antihydrogen in a strong magnetic field

Basing on numerical simulation of classical trajectories, the influence of a strong magnetic field on the rate of the spontaneous radiative recombination of antihydrogen atoms in cold antiproton-positron plasma is theoretically studied under the conditions of the ATHENA and ATRAP experiments carried out in CERN. The effect of the mag netic field is estimated by Monte-Carlo calculation of the change in the cross section of the positron hitting the near-nucleus region with the radius typical for the atomic ground state.

Heterophase semiconductors underaction of irradiations

The history and current state of our heteropfiase photoconducting CdS-PbS films investigations are observed. Films were prepared by the vacuum evaporation method from the materials with limited mu tual solubility. Reasons of increased degradation stability with respect to radiation (in particular y- and electronic irradiations) are found out. Degradation stability is explained by diversion of recombination flow from wide-gap phase to narrow-gap. Radiation stimulated defects also move to narrow-gap phase.

Modelling the dynamics of photonic crystal broad-area surface emitting laser

The lasers beam dynamics in photonic crystal laser is investigated numerically. The decomposition of transverse field distribution in terms of orthogonal modes of photonic crystal structure is used. The relation between the transverse structure of output beam and struc ture of pump region is demonstrated. The modification of the trans verse distribution of the pump allows to control of excitation of se lected transverse mode families. 

Радиотехнические методы анализа многочастотных режимов работы лучевых приборов с продольным взаимодействием

Проведен обзор радиотехнических методов анализа нелинейных усилителей. Предложено представление нелинейного усилителя в виде типового радиотехнического звена, состоящего из входного и выходного фильтров и безынерционного нелинейного элемента. Описаны методы идентификации элементов радиотехнического звена. Обсуждается проблема учета амплитуднофазовой конверсии. Продемонстрирована возможность успешного описания с помощью предложенной модели многочастотных режимов работы СВЧ усилителей.

Contemporary problems in modeling from time series

Mathematical modeling from discrete sequences of experimental data (time series) is an actively developing field in mathematical statistics and nonlinear dynamics. It started from approximation of a set of data points on a plane with a smooth curve, while currently such empiric models take the form of sophisticated differential and difference equations and are capable of describing even nonlinear oscillatory and wave phenomena. Practical applications of the empiric models are various ranging from future forecasts to technical and medical diagnostics.

Solitons and clusters in one-dimensional ensembles of interacting brownian particles

The survey of the studies results of 1D ensembles dynamics of interacting Browniam particles is presented. Properties of both particles and the Fermi-Pasta-Ulam, Toda, Lennard-Jones, Morse interaction potentials are described. The Langevin equations are exhibited and structures and thermodynamic characteristics which may be extracted from data of a numerical integration of the equations are described. Excitations of phonons, cnoidal waves and solitons in dense ensembles and clusters in ensembles of low density are considered.