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1.
The problem is considered of using the PROGRESS transport spacecraft, which will deliver the payload on the ISS, as a free flying platform for realization of space experiments. For maintenance of the ISS 5-6 PROGRESS flights per year are planned. Usually after delivery of the payload the PROGRESS undocks from the ISS and burns down in the Earth atmosphere. However, the operating conditions of its onboard systems allow to prolong operation and to make free flight near to the station and repeatedly to be docked to it. It is offered to use this possibility for performing experiments on Material Science.  相似文献   
2.
A process of manufacture of porous membranes made of aluminum foil (Al 99.99%) by the method of electrochemical anodic oxidation followed by a continuous barrier layer removal with ion-plasma irradiation is described. The membranes having a 8 mm diameter made from AL2O3 with a thickness from 2 to 5 microns thick with a regular channel arrangement are obtained. A possibility to change the channel diameter in the range of 20?C100 nm by adjusting voltage and temperature during the oxidation is shown. We present the experimental dependencies of aluminum and aluminum oxide sputtering coefficients on the energy and incidence angle of xenon ions within the energy range of 100??400 eV.  相似文献   
3.
The radiation spectra of the ionosphere in the 4–5 μm region have been determined from stratospheric balloons by means of the specially elaborated method of the registration of angular and spectral distribution of the radiation. The radiation bands of 4.4 μm and 4.8 μm which have 0.1–0.2 erg cm?2 sr?1s?1. brightness obtained in two flights, are identified with the vibration-rotation transitions of the ion NO+ (0 - 1) and the molecules N14N15 (0 - 1) and CO (0 - 1) and (3 - 2) from altitudes between 120 and 500 km.  相似文献   
4.
We study the influence of additive and parametric slowly varying harmonic (at the Chandler frequency and doubled frequency) and stochastic Gaussian broadband perturbations on mathematical expectations, variances, and covariations of oscillations of the Earth’s pole. The influence of perturbations on both regular and irregular stochastic oscillations is considered in detail. Results of numerical experiments are presented. The developed models and software are included into information resources on the fundamental problem “Statistical dynamics of the Earth’s rotation” of Russian Academy of Sciences.  相似文献   
5.
The necessity of taking many force components disturbing spacecraft (SC) orbits into account is demonstrated for the example of forecasts of GLONASS ephemerides. The disturbances of SCs in high-earth orbits (HEO) and low-earth orbits (LEO) are systematized, and the degree of their effect on SC motion is estimated. Disturbance models are developed that provide essential increases of the accuracy of one-day forecasts of GLONASS and GPS ephemerides. Modeling results are presented that allow, depending on the required accuracy of SC orbit forecasts, the determination of the necessary list of disturbances included in the model.  相似文献   
6.
A mathematical model of perturbed rotational motions of the deformable Earth, adequate to astrometric measurements of the International Earth Rotation Service (IERS), is constructed using methods of celestial mechanics. It is based on the gravitational tidal mechanism of the influence of the Sun and Moon. The authors have found fine resonant structure of interaction of long-period zonal tides (annual, semi-annual, monthly, and two-week) with diurnal and semidiurnal tides. This essential property is reliably confirmed by spectral analysis of the IERS data. In this paper, a numerical simulation of tidal irregularities of the Earth’s axial rotation is performed. The primary emphasis is placed on the analysis of variations of the duration of the day on short time intervals with periods of one year and less (intra-annual oscillations) and their forecast.  相似文献   
7.
A generalization of kinetic and spectral and correlation equations of fluctuations in the Earths rotation is made taking into account the effect of the Moon and planets (these equations form the basis for corresponding stochastic models). Special attention is paid to a parameterized version of kinetic equations based on the method of normal approximation. The application of linear stochastic models for obtaining the spectral and correlation characteristics of the Earths rotation is considered, including the case of random parameters of the tensor of inertia of a deformable Earth. The results can be used for constructing stochastic models of the Earths rotation over time intervals of 6–10 years.Translated from Kosmicheskie Issledovaniya, Vol. 43, No. 1, 2005, pp. 54–66.Original Russian Text Copyright © 2005 by Markov, Dasaev, Perepelkin, I. N. Sinitsyn, V. I. Sinitsyn.  相似文献   
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9.
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   
10.
Numerical models of the thermal budget of the Earth's upper atmosphere in the height range of 90–500km are developed. The main sources and sinks of energy including infra-red radiative cooling by vibrational-rotational bands of NO, CO2, OH and O3 as well as heating and cooling arising from dissipation of turbulent energy and eddy heat transport are taken into account. The calculated temperature and density height profiles are in good agreement with the respective profiles from CIRA 72 and Jacchia 1977 models. It is shown for the models considered that IR-radiative cooling by CO2 and NO in the 15μ and 5.3μ bands, not eddy turbulence provides the major loss of heat from 90 to 180km.  相似文献   
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