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481.
Variations in fluxes of quasi-trapped energetic protons were studied on the basis of the data of the CORONAS-I satellite. These variations are characterized by an increase in the proton fluxes with E P ≥ 1 MeV both in the vicinity of the geomagnetic equator and in the high-latitude region of the magnetosphere. The analysis of structural features of the proton distributions in the regions at L ~ 1–1.1; 3 < L < 4; and L > 4, was performed and made it possible to detect reliably the type of the proton flux increase in this region. The mechanisms of particle scattering leading to the precipitation of energetic protons under conditions of various types of geomagnetic disturbances are considered. 相似文献
482.
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
483.
The results of modeling the thermal deformations of a space radio telescope’s reflecting surface are presented in the paper. Calculations were performed for the versions of the most unfavorable telescope illumination by the Sun. 相似文献
484.
Results of modeling the time behavior of the D st index at the main phase of 93 geomagnetic storms (?250 < D st ≤ ?50 nT) caused by different types of solar wind (SW) streams: magnetic clouds (MC, 10 storms), corotating interaction regions (CIR, 31 storms), the compression region before interplanetary coronal ejections (Sheath before ICME, 21 storms), and “pistons” (Ejecta, 31 storms) are presented. The “Catalog of Large-Scale Solar Wind Phenomena during 1976–2000” (ftp://ftp.iki.rssi.ru/pub/omni/) created on the basis of the OMNI database was the initial data for the analysis. The main phase of magnetic storms is approximated by a linear dependence on the main parameters of the solar wind: integral electric field sumEy, dynamic pressure P d , and fluctuation level sB in IMF. For all types of SW, the main phase of magnetic storms is better modeled by individual values of the approximation coefficients: the correlation coefficient is high and the standard deviation between the modeled and measured values of D st is low. The accuracy of the model in question is higher for storms from MC and is lower by a factor of ~2 for the storms from other types of SW. The version of the model with the approximation coefficients averaged over SW type describes worse variations of the measured D st index: the correlation coefficient is the lowest for the storms caused by MC and the highest for the Sheath- and CIR-induced storms. The model accuracy is the highest for the storms caused by Ejecta and, for the storms caused by Sheath, is a factor of ~1.42 lower. Addition of corrections for the prehistory of the development of the beginning of the main phase of the magnetic storm improves modeling parameters for all types of interplanetary sources of storms: the correlation coefficient varies within the range from r = 0.81 for the storms caused by Ejecta to r = 0.85 for the storms caused by Sheath. The highest accuracy is for the storms caused by MC. It is, by a factor of ~1.5, lower for the Sheath-induced storms. 相似文献
485.
Results of the analysis of 327 sessions of radio occultation on satellite-to-satellite paths are presented. The data are taken in the nighttime polar ionosphere in the regions with latitudes of 67°–88°, and in the period of high solar activity from October 26, 2003 to November 9, 2003. Typical ionospheric changes in the amplitude and phase of decimeter radio waves on paths GPS satellites-CHAMP satellite are presented. It is demonstrated that these data make it possible to determine characteristics of the sporadic E s structures in the lower ionosphere at heights of 75–120 km. Histograms of distribution of the lower and upper boundaries, thickness, and intensity of the E s structures are presented. Dispersion and spectra of amplitude fluctuations of decimeter radio waves caused by small-scale irregularity of the ionospheric plasma are analyzed. The relation of the polar E s structures and intensity of small-scale plasma irregularity to various manifestations of solar activity is discussed. The efficiency of monitoring the ionospheric disturbances caused by shock waves of the solar wind by the radio occultation method on satellite-to-satellite paths is demonstrated. 相似文献
486.
Manned missions onboard orbital stations Salyut-6 and Salyut-7 have led us to the conclusion that a long-term space mission can be viewed as a complex socio-man-machine system whose effectiveness largely depends on the quality of interaction between its subsystems. When analyzing and assessing the reliability of this system, it is important to consider ethical aspects, because they concern human relations, permeating its very component and in the long run determining its efficiency. Psychological and medical examinations before, during and after manned missions have helped us to identify the major points of interaction of the subsystems which require adequate monitoring and optimization using socio-psychological and organization-technical approaches: arrangement and evaluation of the quality of work, arrangement of proper leisure, psychological comfort in the interpersonality and intergroup relations during prolonged space missions. This paper also discusses adaptive changes in the mental and physical state due to prolonged exposure to space flight factors such as microgravity and confinement. 相似文献
487.
I. Ahlers M. Prasli
ka R.A. Tigranyan 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(14):193-198
Plasma and tissue lipids in male SPF Wistar rats flown for 18.5 days aboard the Cosmos 936 biosatellite were analyzed. One group of rats was subjected to artificial gravity by use of a centrifuge during the flight. An experiment simulating known space flight factors other than weightlessness was done on Earth. An increase of total cholesterol in plasma, of nonesterified fatty acids in plasma and brown adipose tissue, of triacylglycerols in plasma, liver, thymus and bone marrow was noted several hours after biosatellite landing. Smaller changes were observed in the terrestrial control experiment. With the exception of triacylglycerol accumulation in bone marrow, these increases disappeared 25 days after biosatellite landing. Exposing the rats aboard the biosatellite to artificial gravity was beneficial in the sense that such exposure inhibited the phospholipid and triacylglycerol increase in plasma and inhibited the increase of triacylglycerol in liver and especially in bone marrow. 相似文献
488.
Yu.A. Akatov T.V. Batenchuk A.M. Borodin V.E. Dudkin A.M. Marenny V.A. Sakovich G.G. Vasilev A.G. Karadjov P.P. Szab I. Fehr W. Malz G. Voigtman D. Hasheganu 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(14):67-71
During the 3rd main expedition on board the “Salyut-6” orbital station in 1979 the integral characteristics of cosmic radiation were measured in various positions inside the manned modules (experiment “Integral”). Measurements were performed with thermoluminescent dosimeters, photographic films and solid state plastic detectors supplied for the experiment by specialists of the USSR, Bulgaria, Hungary, GDR and Romania. The dose gradient inside the manned modules of the station amounted to 70 % for long intervals of time. During the experimental period the dose rate inside the station was 15 to 30 mrad per day. The mean flux of particles with z 6 and LET 200 keV/μm was found to be 0.22 cm−2 day−1. 相似文献
489.
E.N. Vaulina I.D. Anikeeva L.N. Kostina I.G. Kogan L.R. Palmbakh A.L. Mashinsky 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(14):163-169
The effect of weightlessness on chromosomal aberration frequency in preflight irradiated seeds, on the viability, fertility and mutation frequency in , and on the frequency of nondisjunction and loss of X chromosomes in preflight irradiated gametes was studied aboard the Salyut 6 orbital station. The following effects were observed: a flight-time dependent amplification of the effects of preflight -irradiation in . with respect to all the parameters studied; unequal effects in seeds and seedlings of ; and a significant increase in the frequency of nondisjunction and loss of chromosomes during meiosis in females. These observations are discussed in terms of the data of ground-based model experiments and flight experiments with a different time of exposure of objects to weightlessness. An attempt is made to elucidate the role of weightlessness in the modification of ionizing radiation effects. 相似文献
490.
A.A. Imshenetsky L.A. Kuzyurina V.M. Jakshina I.K. Dorofeyeva 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(14):173-177
The influence of lowered gravitation on biomass and CO2 production in , a xerophyte, and , an aqueous spirillum, in liquid nutrient medium on a horizontal clinostat at 0.1 has been studied. As controls we considered: 1) growth under stationary conditions of cultivation with test tubes oriented horizontally; 2) growth on a synchronously revolving centrifuge; and 3) growth on a swing with stirring. A horizontal clinostat at 0.1 g stimulates biomass production and CO2 release in as compared with the controls. growth is reduced as a result of clinostating. The best development and CO2 production are observed under stationary conditions. The results do not support the assumption that microorganisms living in water are more resistant to lowered gravitation than those living in soil. 相似文献