Band properties of the spectral characteristics of laminar media
Band properties of the spectral characteristics of laminar media
A.V. Tikhonravov
Estimates of the spectral characteristics of single-mode waveguides are obtained as a function of the parameters characterizing the smoothness of the wave resistance of the inhomogeneous section of the waveguide and length of this section. It is shown that these estimates allow a priori concepts to be obtained regarding the realizability of the band properties of waveguides required in synthesis.
Show AbstractSolution of the two-dimensional magnetotellurgic problem using Tikhonov regularizing algorithms
Solution of the two-dimensional magnetotellurgic problem using Tikhonov regularizing algorithms
V.B. Glasko, N.I. Ol'khovskaya
It is shown that the general Tikhonov regularizing algorithm applies to the case of a model in which the conduction of the terrestrial core is approximated by smooth functions. The magnetotelluric problem is formulated for a special case of the local conduction distribution: $\sigma(x, z) = \sigma_1(x)\sigma_0(z)$. Using a regularizing algorithm, a mathematical experiment is performed to determine the horizontal inhomogeneity of the geoelectric discontinuity.
Show AbstractLight-beam scanning in para-tellurite crystals
Light-beam scanning in para-tellurite crystals
Z.T. Azamatov, I.B. Belikov, V.B. Voloshinov, F.D. Mamatdzhanov, V.N. Parygin
Light diffraction on ultrasound in the para-tellurite crystal is investigated. For acoustic waves in the frequency range 8.8$\div$80.0 MHz, the Bragg angles of incidence of the optioal beam at the ultrasound is measured. In the frequency range 30.0$\div$50.5 MHz, scanning of the light beam in the first diffractional order is performed, with a diffraction efficiency of 40$\div$80% at a controlling electric power of 120 mW. The features of the scanning are investigated by means of double light scattering on ultrasound. The reflector resolution measured for para tellurite $N=330\pm20$ differs from the calculated value N = 400 by 10-20%. The influence of thermal perturbations on the acoustooptical cell is qualitatively estimated.
Show AbstractDistribution of the gravitational force and plumbline deflections on the surface of Mars
Distribution of the gravitational force and plumbline deflections on the surface of Mars
T.G. Maksimova, N.A. Chuikova
It is proposed to use, as a reference surface, the smoother physical surface of Mars, which is an expansion with respect to normalized spherical functions to the 16-th power. The coefficients of the expansion are determined on the basis of the coefficients of the expansion of the relief and the gravitational potential to the 12-th power. Pictures of the variation in gravitational force with respect to $g_0$ = 372.69 Gal and plumbline deflection at the smoothed physical surface are given.
Show AbstractField asymptote of a vertex function
Field asymptote of a vertex function
Yu.M. Loskutov, V.V. Skobelev
By summing diagrams of ladder type, the asymptote of a vertex function in a superstrong magnetic field is found. It is shown that the field vertex contributions to the matrix elements are small in comparison with the corresponding contributions of the mass and polarization operators.
Show AbstractNew class of static spherically symmetric solutions of the Einstein equations in the presence of matter. I
New class of static spherically symmetric solutions of the Einstein equations in the presence of matter. I
Yu.N. Vlasenko, P.I. Pronin
A new method of obtaining internal static solutions of the Einstein equations is proposed and used to find a series of solutions for spherically symmetric configurations. The matching conditions with the external Schwartzschild solution are considered.
Show AbstractAccurate solutions of the Dirac equations in a quantized pseudoscalar wave
Accurate solutions of the Dirac equations in a quantized pseudoscalar wave
V.R. Khalilov, V.K. Perez-Fernandez
Accurate solutions of the Dirac equation are obtained, describing a nucleon doublet in the classical field of a plane pseudoscalar wave, against the background of which there are single-mode quantum excitations.
Show AbstractParametric generation in an oscillatory loop with discontinuously changing parameters
Parametric generation in an oscillatory loop with discontinuously changing parameters
V.P. Komolov, D.A. Tishchenko, P.N. Shashkov
The conditions of parametric excitation of oscillations in a loop with discontinuously changing parameters determining the relations between the durations of residence of the loop in discrete states and the parameter values in these states are described. It is shown that such a loop has a set of excitation modes of oscillations of different form. The results of experimental investigation of the balance parametric loop with discontinuously changing capacitance, in which 16 generation regions were observed, are presented.
Show AbstractRegions of excitation of oscillations in a loop with discontinuous capacitance modulation
Regions of excitation of oscillations in a loop with discontinuous capacitance modulation
V.P. Komolov, D.A. Tishchenko, P.N. Shashkov
Relations for the limits of the regions of excitation of oscillations in a loop with discontinuous modulation of the capacitance are describied; the relations are obtained on the basis of analysis of the stability of the solution of the corresponding Hill equation. It is shown that the excitation zones may be divided into discrete regions; the number of these regions does not exceed the number of zones and depends on the parameters of the modulating perturbation. Results are given of an experimental investigation of the excitation of a parametric loop with rectangular videopulse pumping, with a depth of capacitance modulation varying within the range 0$\div$0.6.
Show AbstractMathematical model of the mean-velocity profile of a benthic density current
Mathematical model of the mean-velocity profile of a benthic density current
A.Yu. Pyrkin
A two-dimensional steady turbulent benthic density current with a specified density profile is considered. The solution of the equations in the approximation of constant turbulent viscosity over the vertical is in good agreement with experimental results.
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