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101.
Complex vibrations of the Bernoulli-Euler sandwich beams are considered. The solution is performed by the numerical methods of finite elements in the Bubnov-Galerkin form and finite differences of the second order of accuracy. The approaches for control of chaotic vibrations in the Bernoulli-Euler sandwich beams are proposed. 相似文献
102.
B. A. Antuf’ev 《Russian Aeronautics (Iz VUZ)》2017,60(1):9-12
The paper presents an approximate solution of a problem on dynamic behavior of a wing leading edge assembly discretely reinforced by a system of ribs and coated with thermal protection coating. 相似文献
103.
V. K. Saul’skii 《Cosmic Research》2017,55(4):275-289
Satellite systems for the periodic survey of a given range of the Earth’s latitudes have been analyzed. As a rule, the efficiency of the satellite systems is estimated based on the maximum interruption, i.e., the maximum time interval that appears when surveying. However, this performance cannot serve as a full criterion for the quality of the survey, since it does not reflect all survey interruptions with their frequencies. To adequately analyze the operation of the satellite system, it is necessary to use the frequency distribution function of the survey interruptions; its determination is a complex problem and has not yet been solved in the general case. In this paper, we propose a method for calculating the set of all interruptions and frequencies suitable for any multisatellite systems with an arbitrary structure. The method is based on the vector model of the Earth’s survey. To estimate the efficiency of the satellite system operation, a complex criterion has been recommended that takes into account all survey interruptions and their frequencies. Two examples of the application of the developed method have been presented. 相似文献
104.
Kobayashi Masanori Shibata Hiromi Nogami Ken’ichi Fujii Masayuki Hasegawa Sunao Hirabayashi Masatoshi Hirai Takayuki Iwai Takeo Kimura Hiroshi Miyachi Takashi Nakamura Maki Ohashi Hideo Sasaki Sho Takechi Seiji Yano Hajime Krüger Harald Lohse Ann-Kathrin Srama Ralf Strub Peter Grün Eberhard 《Space Science Reviews》2020,216(8):1-49
Space Science Reviews - In this chapter, we review the contribution of space missions to the determination of the elemental and isotopic composition of Earth, Moon and the terrestrial planets, with... 相似文献
105.
Cosmic Research - We have analyzed the experimental data obtained in 2016–2019 from the measurements of plasma disturbances and electric currents induced at ionospheric altitudes upon the... 相似文献
106.
3D ANSYS CFX conjugate calculation was carried out to compare cooling effectiveness of the high pressure turbine vane platforms with the film cooling and the convection-film cooling. 相似文献
107.
Radio bursts in the frequency range 100–1500 kHz and fluxes of energetic electrons with energies of 20–450 keV recorded onboard the Interball-1 satellite during prominent chromospheric flares on the Sun are studied. The time of propagation of the electrons to the Earth is estimated using the method of comparison of the moments of the beginning of radio emission generation during the explosive phase of the flare and the arrival of the accelerated electrons to the Earth. 相似文献
108.
N. V. Emelyanov J. -E. Arlot M. I. Varfolomeev S. N. Vashkov’yak A. A. Kanter S. M. Kudryavtsev L. P. Nasonova V. S. Ural’skaya 《Cosmic Research》2006,44(2):128-136
A knowledge base for natural satellites of planets is created. On the basis of observations, new numerical models of motion are constructed for all 96 outer satellites of Jupiter, Saturn, Uranus, and Neptune. A special database is compiled from all available observational data for natural satellites of planets, as well as a bibliographical database and information system of physical and orbital parameters of planets and satellites. The tools for calculations of ephemerides of all natural satellites (except for the Moon) of planets are developed. They represent the final result of studies and actually incorporate the entire knowledge about dynamics of the satellites of planets. Also developed are special ephemerides in order to observe singular phenomena in the apparent motion of the satellites of planets. A computer environment and the Internet allowed us to concentrate all above-listed options in a single toolkit easily available to any user in the world. 相似文献
109.
A. V. Shchukin A. V. Il’inkov S. G. Dezider’ev S. N. Ivanov 《Russian Aeronautics (Iz VUZ)》2013,56(4):384-389
This paper reports the results of an experimental study of heat transfer using a model of the internal cooled surface of the turbine blade leading edge. We investigated a joint action of air jets and hemispherical protrusions on heat transfer from the concave surface of the leading edge model to air. 相似文献
110.
We consider the angular motion of an axi-symmetrical satellite equipped with an active magnetic attitude control system. Dynamics of the satellite is studied on the entire control loop, consisting of a bunch of three successively used algorithms. The control cycle includes the stages of nutation damping, spinning up the satellite about its symmetry axis, and reorienting the symmetry axis into a preset direction in the inertial space. The results are confirmed by numerical simulations. 相似文献