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791.
Cosmic Research - Features of the implementation of a beam-pulse amplifier (BPA) of whistler waves in magnetospheriс enhanced and depleted ducts with refraction reflection are considered.... 相似文献
792.
V. G. Dmitriev O. V. Egorova S. I. Zhavoronok L. N. Rabinskii 《Russian Aeronautics (Iz VUZ)》2018,61(2):165-174
In this paper, we develop the consistent mathematical models and appropriate lowconsuming numerical methods for investigating the nonlinear strain and buckling behavior of statically loaded thin-walled structures with cutouts. The numerical simulation allowed us to study the effects of the dimensions of rectangular cutouts on the buckling of cylindrical shells loaded by the external pressure. 相似文献
793.
O.H.库德尔雅绍夫 《航空精密制造技术》1999,35(6)
介绍了俄罗斯大型运载火箭壳体结构的材料。装配和焊接概况.对我国同类型航天火箭的制造有参考和借鉴意义. 相似文献
794.
N. A. Vlasova E. A. Ginzburg V. V. Kalegaev I. N. Myagkova M. I. Panasyuk I. A. Rubinshtein M. O. Riazantseva P. M. Svidsky V. I. Tulupov 《Cosmic Research》2013,51(5):319-325
Results of the comparative analysis of the dynamics of SCR fluxes with energies of 1–100 MeV in the interplanetary environment according to the data of the ACE and Wind spacecraft and within the Earth’s magnetosphere according to the data of the GOES-15 and Electro-L satellites in the region of geostationary orbits, and POES-19 and Meteor-M1 in the region of polar caps during two increases in SCR of January 19–31, 2012, are presented. It is shown that the decrease in the efficiency of SCR penetration into the Earth’s magnetosphere in the region of the orbits under study on January 28, 2012, is related to the passage of the Earth’s magnetosphere through the interplanetary environment structure with a quasi-radial interplanetary magnetic field and a small pressure of the solar wind. 相似文献
795.
The results of comparison of the characteristics of sharp boundaries of small-scale and medium-scale solar wind structures in the case of their simultaneous observation on widely spaced spacecraft are described. It is shown that even very sharp boundaries, with duration of several seconds or fractions of a second, retain their amplitude and remain very sharp during solar wind propagation to distances of up to a million kilometers. 相似文献
796.
797.
Harry O. Ruppe 《Space Policy》1987,3(2)
Fearing that mistaken decisions may be made, the author offers his comments to clarify the future possibilities for Ariane, Hermes and Columbus. The decisions soon to be taken on the manned spaceflight programme will affect the future of the entire European space programme. The possibilities for air-breathing propulsion are also reviewed. 相似文献
798.
Results of laboratory measurements of the dielectric characteristics of lunar soil samples returned to the Earth by the Luna and Apollo missions have been analyzed. The feasibility of determining the density of the upper cover of the Moon from the permittivity, which is restored as a result of solving the inverse problem of radiolocation, has been discussed. A formula has been proposed for approximating the frequency dependence of the loss tangent for the regolith and bedrock. Relationships have been deduced for estimating the percentage of metal oxides in the lunar soil. 相似文献
799.
O.?V.?SapunovaEmail author N.?L.?Borodkova V.?G.?Eselevich G.?N.?Zastenker Yu.?I.?Yermolaev 《Cosmic Research》2017,55(6):396-402
The paper is concerned with studying the thickness of fronts of 38 interplanetary shocks detected by the BMSW instrument, which is a part of the scientific payload of the SPEKTR-R spacecraft, which was launched into a highly elliptical orbit in 2011. The main parameters of the interplanetary shocks have been calculated as follows: the ratio of thermal pressure to magnetic pressure before the front β, the angle between the shock front normal and the undisturbed magnetic field θBn, the ratio of the shock propagation velocity to the magnetosonic velocity in the undisturbed region Mms, and the shock front velocity relative to the Earth. It has been shown that the front thickness determined from the plasma parameters approximately matches the front thickness obtained from the magnetic field measurements and lies between 0.5 and 5 proton inertial lengths. In some events, the oscillations have been observed (upstream and downstream of the shock) in plasma parameters and in the magnetic field data. The length has been found to be between 0.5 and 6 proton inertial lengths for the preceding oscillations and between 0.5 and 10 proton inertial lengths for the following oscillations. The average value of the proton inertial length is 62 km. 相似文献
800.
R.R. Rosa M. Karlický T.B. Veronese N.L. Vijaykumar H.S. Sawant A.I. Borgazzi M.S. Dantas E.B.M. Barbosa R.A. Sych O. Mendes 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
We analyze the weak component of the localized temporal pattern variability of 3 GHz solar burst observed by the Ondrejov radiospectrograph. A complex, short and weak impulsive sample from the time series was analyzed by applying a method based on the gradient pattern analysis and discrete wavelet decomposition. By analyzing canonical temporal variability patterns we show that the new method can reliably characterize the phenomenological dynamical process of short time series (N ? 103 measurements) as the radio burst addressed here. In the narrowest sense, by estimating the mutual information distance in the gradient spectra, we show that the fluctuation pattern of the short and weak 3 GHz impulsive solar burst, with energetic amplitudes <350 SFU, is closer to the intermittent and strong MHD turbulent variability pattern. 相似文献