Анализ профиля скорости вязкой cреды, движущейся вдоль шероховатой поверхности
Анализ профиля скорости вязкой cреды, движущейся вдоль шероховатой поверхности
В.В. Комаров, И.О. Стурейко
Предложен квантовомеханический подход к решению гидро- и газодинамических задач о турбулентных течениях вязких сред. Проведен анализ возмущения профиля скорости турбулентного течения в канале, вызванного прерывистым пристеночным слоем. Рассчитаны колебания стенок канала, сопровождающие турбулентное течение.
Show AbstractО стереовозможностях системы из двух гамма-телескопов, регистрирующих угловое распределение черенковского излучения атмосферных ливней
О стереовозможностях системы из двух гамма-телескопов, регистрирующих угловое распределение черенковского излучения атмосферных ливней
А.М. Анохина$^1$, В.И. Галкин$^1$, Г.П. Кузнецова$^1$, Т.М. Роганова$^1$, А.А. Степанян$^2$
Статистическое моделирование процесса регистрации гамма- и фонового излучения сверхвысокой энергии черенковским гамма-телескопом ГТ-48 Крымской астрофизической обсерватории показало, что невозможно эффективное выделение атмосферных ливней, вызываемых гамма-квантами, по глубине максимума черенковского излучения. Увеличение расстояния между телескопами не приведет к повышению эффективности отбора гамма-событий.
Show AbstractМетод определения фазовой скорости перемещающихся ионосферных возмущений
Метод определения фазовой скорости перемещающихся ионосферных возмущений
В.Д. Гусев, А.Г. Вологдин, Н.В. Карабанов, Д.В. Кирьянов
Теоретически обосновывается метод определения фазовой и групповой скорости перемещающихся ионосферных возмущений. Метод основан на спектральном анализе угломерно-доплеровских данных дистанционного радиозондирования ионосферы. Метод иллюстрируется на примере обработки экспериментальных данных.
Show AbstractOptimal decisions in the theory of possibilities
Optimal decisions in the theory of possibilities
Yu.P. Pyt'ev
Decision making methods of the theory of possibilities, based on minimization of possibility and/or necessity of losses determined by the decision, are considered.
Show AbstractStatistical thermodynamics and structure of rigid oxygen
Statistical thermodynamics and structure of rigid oxygen
P.N. Nikolaev, A.I. Sokolov, O.V. Kuz'mina
Basing on the cell-structure expansion method, statistical thermodynamics and structure of rigid oxygen are constructed. It is demonstrated that the structure of all its three phases can be described with high accuracy using the two-center interaction potential.
Show AbstractOn the evolution of two-dimensional inversion domains in the magnetic field of spiral galaxies
On the evolution of two-dimensional inversion domains in the magnetic field of spiral galaxies
A.A. Bykov, V.Yu. Popov
It is shown that the area of an inversion domain in the magnetic field of a spiral galaxy decreases linearly in time irrespective of the inversion domain shape. This linear dependence occurs because the drift velocity of the transition layer bounding the inversion domain is proportional to the layer curvature (or, which is the same, is inversely proportional to the radius of curvature). The lifetime of an inversion domain of arbitrary shape is calculated. It turns out to be proportional to the initial area of the inversion domain. The evolution of multiply connected inversion domains (i.e., domains whose interior contains some additional inversion domains) is investigated.
Show AbstractOn the composite-type model equation describing transient processes in semiconductors
On the composite-type model equation describing transient processes in semiconductors
M.O. Korpusov, Yu.D. Pletner, A.G. Sveshnikov
A mathematical model describing transient processes in semiconductors has been studied. It has been shown that the original physical statement of the problem is reduced to the initial-boundary-value problem for a higher-order partial derivative equation of the composite type. Consideration of an appropriate one-dimensional initial-boundary-value problem has revealed full agreement of theoretical results obtained based on the proposed mathematical model with the observed dynatnic effect of space charge stratification in a semiconductor.
Show AbstractNonparametric methods of the "astro-gravitational" correlation
Nonparametric methods of the "astro-gravitational" correlation
A.V. Gusev, V.K. Milyukov
An adaptive algorithm for detecting weak "gravitational" pulses, correlated with astrophysical processes, against the background of stationary noise with unknown distribution is developed.
Show AbstractIonosphere ray radiotomography with inclusion of refraction
Ionosphere ray radiotomography with inclusion of refraction
E.S. Andreeva, V.E. Kunitsyn, A.Yu. Popov
Using the example of the ionosphere radiotomography, a nonlinear statement of the ray tomography problem with inclusion of sounding ray refraction is considered. It is shown that, in the case of weak refraction, the nonlinear tomography problem can be solved as a sequence of linear problems whose solution process is realized by an iterative procedure with every approximation of the refractive index calculated using the ray trajectory obtained in the preceding approximation.
Show AbstractGeneration of a wave with a frequency $3\omega_1-\omega_2$ on reflection from the isotropic gyrotropic medium surface
Generation of a wave with a frequency $3\omega_1-\omega_2$ on reflection from the isotropic gyrotropic medium surface
S.N. Volkov, S.M. Donskoi, A.V. Zasimova, N.I. Koroteev, V.A. Makarov
The generation of a reflected wave with a frequency of $3\omega_1-\omega_2$ under inclined incidence of two elliptically polarized plane waves with frequencies $\omega_1$ and $\omega_2$ on the surface of an isotropic gyrotropic medium is studied. It is shown that the generation is most efficient in grazing reflection of the wave with a frequency $3\omega_1-\omega_2$. It is found that there exist such incidence angle ranges wherein the reflected wave becomes nonuniform, and its amplitude decreases exponentially with distance from the medium surface.
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