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201.
B. A. Antuf’ev 《Russian Aeronautics (Iz VUZ)》2008,51(1):1-4
The dynamic and static uncoupled thermoelasticity problems for a thin shallow cylindrical shell under the action of local temperature field is considered. This field appears as a result of mechanical damage of a protective layer region. 相似文献
202.
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
203.
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
204.
G. Klingelhöfer J. Brückner C. D’uston R. Gellert R. Rieder 《Space Science Reviews》2007,128(1-4):383-396
The Alpha Particle X-Ray Spectrometer (APXS) is a small instrument to determine the elemental composition of a given sample.
For the ESA Rosetta mission, the periodical comet 67P/Churyumov-Gerasimenko was selected as the target comet, where the lander
PHILAE (after landing) will carry out in-situ observations. One of the instruments onboard is the APXS to make measurements
on the landing site. The APXS science goal is to provide basic compositional data of the comet surface. As comets consist
of a mixture of ice and dust, the dust component can be characterized and compared with known meteoritic compositions. Various
element ratios can be used to evaluate whether chemical fractionations occurred in cometary material by comparing them with
known chondritic material. To enable observations of the local environment, APXS measurements of several spots on the surface
and one spot as function of temperature can be made. Repetitive measurements as function of heliocentric distance can elucidate
thermal processes at work. By measuring samples that were obtained by drilling subsurface material can be analyzed. The accumulated
APXS data can be used to shed light on state, evolution, and origin of 67P/Churyumov- Gerasimenko. 相似文献
205.
The notion of a transfer zero as applied to improper dynamic systems is considered. An algorithm that makes it possible to reduce the calculation of improper system zeroes to finding ordinary system zeroes is presented. A method for providing the specified position of a transfer zero set in the improper dynamic system having an equal number of inputs and outputs is proposed. 相似文献
206.
I. V. Bychkov V. A. Voronov E. I. Druzhinin R. I. Kozlov S. A. Ul’yanov B. B. Belyaev P. P. Telepnev A. I. Ul’yashin 《Cosmic Research》2013,51(3):189-198
The paper presents the first part of results of basic research for development of a combined system of high-precision stabilization of the optical telescope for the international observatory Speckr UF (currently under design) planned to study emission of stars in the UV waveband. A new direct method used in these studies for calculating program controls is described. The results of numerical experiments are presented. 相似文献
207.
V. M. Petrov V. V. Bengin V. A. Shurshakov M. I. Panasyuk Yu. V. Kutuzov O. V. Morozov A. G. Myasnikov M. V. Tel’tsov A. V. Markov A. N. Volkov V. I. Lyagushin I. V. Nikolayev A. P. Alexandrin 《Cosmic Research》2006,44(2):106-110
The results of radiation control onboard the Service Module of the International Space Station are considered for the period of increased radiation background from 28 to 30 October, 2003. The values of additional irradiation dose caused by strong solar proton events on October 28 and 29, 2003 are obtained. A comparison is made with similar data obtained in the periods of disturbed radiation conditions of fall 2001. The results of estimating the dependence of the absorbed dose on the shield thickness, based on the onboard measurements, are presented. It is established that the daily-averaged dose power onboard the International Space Station increased after the solar proton events of October 2003. 相似文献
208.
V. S. Prokudina V. N. Kuril’chik Yu. I. Yermolaev K. Kudela M. Slivka 《Cosmic Research》2009,47(1):14-21
Radio bursts in the frequency range of 100–1500 kHz, recorded in 1997–2000 on the INTERBALL-1 satellite during the solar flares preceding the strong geomagnetic storms with D st < ?100 nT, are analyzed in this paper. The observed long-wave III-type radio bursts of solar origin at frequencies of 1460 and 780 kHz were characterized by large values of the flux S f = 10?15 ?10?17 W/m2 Hz and duration longer than 10 min. The rapid frequency drift of a modulated radio burst continued up to a frequency of 250 kHz, which testified that the exciting agent (a beam of energetic electrons) propagated from the Sun to the Earth. All such flares were characterized by the appearance of halo coronal mass ejections, observed by the LASCO/SOHO, and by the presence of a southward Bz-component of the IMF, measured on the ACE and WIND spacecraft. In addition, shortly after radio bursts, the INTERBALL-1 satellite has recorded the fluxes of energetic electrons with E > 40 keV. 相似文献
209.
Robert Ullrich Jeremy McCauley Paul Turin Ken McKee Bill Donokowski 《Space Science Reviews》2008,136(1-4):185-201
An essential component of the STEREO IMPACT investigation is its nearly 6 m long boom that provides several of the instruments with a sufficiently clean magnetic environment and minimally restricted fields of view, while having the required rigidity to ensure the spacecraft pointing accuracy for the STEREO imaging investigations. Details of the customized telescoping IMPACT Boom design, construction and testing are described in this review. The successful completion and verification of the IMPACT Booms represents a demonstration of the use of Stacers as motive forces for rigid boom deployment. 相似文献
210.
S. A. Mikhailov A. M. Girfanov A. B. Bochkareva A. S. Fal’ko 《Russian Aeronautics (Iz VUZ)》2008,51(1):11-15
The results of studying the influence of physical and mechanical properties of composite materials on balancing characteristics and loading of a helicopter under changes of climatic operational conditions are described. 相似文献