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941.
The problem of stability of the trivial equilibrium position in the Sitnikov problem is considered in the first approximation.
The first approximation is shown to have the form of a linear second-order equation with time-periodic coefficient (the Hill-type
equation). The equilibrium stability was studied on the basis of equation regularization in the vicinity of a singular point
with subsequent calculation of the trace a of the monodromy matrix. The equilibrium stability is shown to be stable for almost all values of eccentricity e from the [0, 1] interval. The instability takes place on the discrete set of e values, when the mutipliers are multiple (with non-simple elementary divisors), e = 1 being a point of crowding of this set. 相似文献
942.
A. V. Sedel’nikov 《Russian Aeronautics (Iz VUZ)》2008,51(1):84-86
Problems of revealing and forming a generalized parameter are considered to obtain an adequate estimation of microaccelerations aboard a spacecraft with the aid of a real part of the fractal Weierstrass-Mandelbrot function (WMF) at the phase identically equal to zero. 相似文献
943.
G. P. Lyubimov N. A. Vlasova V. I. Tulupov E. A. Chuchkov B. Ya. Shcherbovsky S. I. Ermakov 《Cosmic Research》2011,49(6):477-484
Results of the analysis of specific features of solar activity, dynamics of solar cosmic ray fluxes, and state of the interplanetary
medium are presented for the period December 5–18, 2006. The data analysis is based on new model concepts on coronal and interplanetary
propagation of solar cosmic rays: partial capture into the magnetic field traps and oscillations at reflections from magnetic
mirrors. Some new hypotheses about possible relations of the features of the interplanetary medium with processes in the Earth’s
magnetosphere are put forward: the influence of the discrete interplanetary medium on processes in the Earth’s magnetosphere
does exist always and, in this sense, it is a fundamental phenomenon; the discreteness of the inter-planetary medium can be
one of the causes of geomagnetic substorms. 相似文献
944.
A. M. Dulliev 《Cosmic Research》2011,49(1):72-81
Based on the results of paper [1] by G.V. Mozhaev, joint perturbations produced by nonsphericity of the Earth and by attraction
of the Moon and the Sun are investigated using the method of averaging. Arbitrary number of spherical harmonics was taken
into account in the force function of the Earth’s gravitational filed, and only the principal term was retained in the perturbing
function of the Sun. In the perturbing function of the Moon two parallactic terms were considered in addition to the dominant
term. The flight altitude was chosen in such a way that perturbations produced by the Sun and Moon would have the second order
of smallness relative to the polar oblateness of the Earth. As a result, the formulas for calculation of satellite coordinates
are derived that give a high precision on long time intervals. 相似文献
945.
I. Sh. Sharafeev 《Russian Aeronautics (Iz VUZ)》2008,51(4):430-434
Problems of the influence of investigation subject evolution on the technological-purpose automation systems using as an example technical labor rating are considered. 相似文献
946.
947.
S. G. Margulis 《Russian Aeronautics (Iz VUZ)》2008,51(2):145-151
A model of reversal jet interaction with a solid particle and particle throw from the runway surface to the GTE inlet is proposed. The calculation results are compared with experimental data on foreign object throw from the runway surface in the Tu-154 airplane landing. We present the regularities that make it possible to develop design and operational measures to improve protection of engines with thrust reversal when they are located behind the wing at the fuselage sides. 相似文献
948.
Statistical properties of magnetic field and plasma flux fluctuations outside the Earth’s magnetosphere are studied on various
time scales based on the INTERBALL-1 satellite data. The analysis of “rough” turbulence characteristics has shown that turbulence properties in various parts
of the magnetosheath are distinct. The spectral density of the magnetic field undergoes a break at a frequency of ∼0.5 Hz.
As a more “fine” characteristic of the fluctuations on various time scales, changes in the shape and parameters of the probability
density function were studied. The analysis of the height of a maximum of the probability density function P(0) and of the kurtosis values have shown the presence of two asymptotic modes of P(0), which are characterized by different power laws. The critical scale, on which the properties of P(0) change, corresponds, presumably, to the scales of the Larmor radius of ions. Based on the results of studying structural
functions of various orders, the conclusion is drawn that small-scale turbulence in the foreshock and magnetosheath is described
by different phenomenological models. 相似文献
949.
950.
R. R. Gubaev 《Russian Aeronautics (Iz VUZ)》2008,51(2):205-208
A possibility of using Lagrange’s functional as a criterion for quantitative estimation of the quality of internal displacement approximation when calculating rigidity and strength of an elastic deformable body is considered. 相似文献