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The kinetic equation of Wigner -- Vlasov -- Boltzmann with collision integral in relaxation BGK (Bhatnagar, Gross and Krook) form in coordinate space for quantum non--degenerate (Maxwellian) collisional plasma is used. Exact expression (within the limits of considered model) is found. The analysis of longitudinal dielectric permeability is done. It is shown that in the limit when Planck's constant tends to zero of expression for dielectric permettivity transforms into the classical case of dielectric permettivity. At small values of wave number it has been received the solution of the dispersion equation. Damping of plasma oscillations has been analized. The analytical comparison with the dielectric Mermin' function received with the use of the kinetic equation in momentum space is done. Graphic comparison of the real and imaginary parts of dielectric permettivity of quantum and classical plasma is done also., Comment: 25 pages, 14 figures

Electric conductivity and dielectric permeability of the non-degenerate electronic gas for the collisional plasmas under arbitrary degree of degeneration of electron gas is found. The kinetic equation of Wigner - Vlasov - Boltzmann with collision integral in relaxation form BGK (Bhatnagar, Gross and Krook) in coordinate space is used. Dielectric permeability with using of the relaxation equation in the momentum space has been received by Mermin. Comparison with Mermin's formula has been realized. It is shown, that in the limit when Planck's constant tends to zero expression for dielectric permeability passes in the classical., Comment: 16 pages, 0 figures

The linearized kinetic equation modelling behaviour of the degenerate quantum bose gas with the frequency of collisions depending on momentum of elementary excitations is constructed. The general case of dependence of the elementary excitations energy on momentum according to Bogolyubov formula is considered. The analytical solution of the half-space boundary problem on temperature jump on border of degenerate bose gas in the presence of a Bose - Einstein condensate is received. Expression for Kapitsa resistance is received., Comment: 28 pages,4 figures

We construct a kinetic equation simulating the behavior of degenerate quantum Bose gases with the collision rate proportional to the molecule velocity. We obtain an analytic solution of the half--space boundary--value Smoluchowski problem of the temperature jump at the interface between the degenerate Bose gas and the condensed phase., Comment: 11 pages, 1 figures

We construct a kinetic equation modeling the behavior of degenerate quantum Bose gases whose collision rate depends on the momentum of elementary excitations. We consider the case where the phonon component is the decisive factor in the elementary excitations. We analytically solve the half-space boundary value problem of the temperature jump at the boundary of the degenerate Bose gas in the presence of a Bose -- Einstein condensate., Comment: 9 pages, 2 figures

When highly viscous oil is produced at low temperatures, large pressure drops will significantly decrease production rate. One of possible solutions to this problem is heating of oil well by hot water recycling. We construct and analyze a mathematical model of oil-well heating composed of three linear parabolic PDE coupled with one Volterra integral equation. Further on we construct numerical method for the model and present some simulation results., Comment: 9 pages, 2 figures, Conference on Applied Mathematics and Scientific Computing, Brijuni, Croatia, June 23-27, 2003