Reflection of electromagnetic waves from the surface of a cubic ferrite

The reflectivity of electromagnetic waves incident on the surface of a semi-infinite nonconducting cubic ferrite was found both analytically and numerically with inclusion of spin-wave damping. The frequency and field dependences of the reflectivity were found for various values of the damping parameter and the anisotropy and magnetostriction constants in a region far from the point of the orientational phase transition and at this point. It is shown that the reflectivity has peaks near the frequencies of ferromagnetic, magnetoacoustic, and magnetostatic resonances. The peak amplitude decreases with increasing spin-wave damping. At frequencies below the magnetoelastic gap, the reflectivity can take on anomalously small (down to zero) and anomalously large (up to unity) values. These frequencies can lie in the microwave range.     

Determination of Residual Stresses in Products in Additive Production by the Layer-by-Layer Photopolymerization Method

A computational-experimental model for identifying the residual (shrinkage) stresses arising in parts after their additive manufacturing by the layer-by-layer photopolymerizationmethod is given. The model is based on an analysis of flexible shrinkage strains of a series of specimens shaped as plate-strips with the same parameters but with different polymerization time which is prescribed in their manufacturing on the 3d-printer.     

Effect of the Electrode Radii on the Pump Discharge width and KrF Laser Radiation

Russian Physics Journal - The effect of the electrode shapes on the pump discharge width and the energy of radiation of the KrF laser with pulse duration of 30 ns is investigated by the method of...     

Acoustic field generated by a beam of protons stopping in a water medium

In an experiment with a beam of protons accelerated up to an energy of 200 MeV, the space-time structure of the hydroacoustic field generated by protons stopping in the water medium was observed. The contributions of three components were separated: a cylindrical wave diverging from the middle part of the acoustic antenna and the signals from the ends of the antenna, namely, from the region of the maximal energy density release by protons (the Bragg peak) and from the other end corresponding to the beam entrance into water.     

Stability estimates for linear stochastic systems with deviating argument of neutral type

We study linear stochastic differential equations with deviating argument of neutral type and establish sufficient conditions of stability. The functions determining the initial perturbations of solutions are found.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 45, No. 6, pp. 834–842, June, 1993.     

Asymptotics of the solution of an initial-boundary value problem for a singularly perturbed parabolic equation in the case of double root of the degenerate equation

For a singularly perturbed parabolic equation, we construct and justify the asymptotics of the classical solution of an initial-boundary value problem in the case of a double root of the degenerate equation. This case substantially differs from the case of a simple root in that the scales of the boundary layer variables are different.