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791.
从空间飞行器入射进电离层的调制电子束产生的高频波辐射 总被引:2,自引:1,他引:1
在主动束-等离子体试验中,调制电子束从空间飞行器入射进电离层等离子体将会产生电磁波辐射,在不同试验条件下电磁波辐射机理也不一样,由电子束纵向约束性产生电磁波辐射是其中之一.对半无界稀薄调制电子束从空间飞行器入射进电离层等离子体时所产生的波现象进行了理论分析和数值计算.结果表明,当调制电子束沿磁力线入射时,会在电离层等离子体中产生高频电磁波辐射,该辐射主要集中在垂直于入射电子束运动方向的平面内. 相似文献
792.
V. I. Tret’yakov I. G. Mitrofanov Yu. I. Bobronitskii A. V. Vostrukhin N. A. Gunko A. S. Kozyrev A. V. Krylov M. L. Litvak M. Lopez-Alegria V. I. Lyagushin A. A. Konovalov M. P. Korotkov P. V. Mazurov M. I. Mokrousov A. V. Malakhov I. O. Nuzhdin S. N. Ponomareva M. A. Pronin A. B. Sanin G. N. Timoshenko T. M. Tomilina M. V. Tyurin A. I. Tsygan V. N. Shvetsov 《Cosmic Research》2010,48(4):285-299
793.
G. N. Zastenker I. V. Koloskova M. O. Riazantseva A. S. Yurasov J. Safrankova Z. Nemecek L. Prech P. Cagas 《Cosmic Research》2014,52(1):25-36
This paper describes the results of studying the helium component of the solar-wind ion-flux measurement by the BMSW instrument on the Spektr-R satellite with a time resolution of 3 s. In contrast to most previous works that presented values averaged over large (hourly average or daily average) intervals, we have shown that the relative helium-ion abundance in the solar wind experiences considerable (by a few percent and even 10%) variations on such short intervals as 10 seconds or even several seconds. 相似文献
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795.
796.
L. Shakun N. Koshkin E. Korobeynikova D. Kozhukhov O. Kozhukhov S. Strakhova 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2021,67(6):1743-1760
With a growing number of resident space objects (RSOs), the facilities for near-Earth space surveillance have to cope with increasing workload. It also applies to low-cost small optical surveillance facilities which may present regional, national and global networks. Improved methods of planning and scheduling optical telescopes are required to use these instruments efficiently. Today, optical observations are only feasible if the following quite stringent requirements are met: the object should be illuminated by sunlight, and it should be above while the Sun is below the observer’s horizon. For different orbits, these preconditions result in varying degrees of the space object observability at various ground-based sites. Certainly, satellites in low Earth orbit (LEO) are particularly difficult to observe. This study aims at developing a new technique for assessing observability of a satellite in different types of orbits – namely, low, medium and high Earth orbits, imaging of the opportunity for its visibility in respective diagrams and their analysing for the existing near-Earth population of RSOs. Unlike other researches, wherein one or several observational stations have been chosen as target sites for in-depth analyses of visibility of all the satellites or just the selected ones, the present study focuses on examining the probability of optical surveillance of satellites in a certain orbit from any locations worldwide. It offers considerable scope for automation of surveillance planning and scheduling optical surveillance networks. 相似文献
797.
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
798.
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
799.
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
800.
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