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261.
S. A. Naroenkov 《Cosmic Research》2010,48(5):455-458
Numerous discoveries of asteroids unknown earlier led to a multiple increase in the number of information on small bodies
of the Solar System. Huge volumes of information accumulated and obtained at observations of objects approaching the Earth’s
orbit require storing and prompt processing, presenting more and more possibilities for studying distributions of small bodies
of the Solar System and ways of their evolution. That is why development of information systems which will contain large volumes
of data on small bodies of the Solar System and facilities for processing these data is actual and promising direction of
activity. 相似文献
262.
Concept of monitoring for thermostressed state and service life of aircraft gas turbine engine blades 总被引:1,自引:0,他引:1
G. G. Kulikov V. A. Trushin A. I. Abdulnagimov A. A. Ganeev 《Russian Aeronautics (Iz VUZ)》2016,59(1):77-83
A concept of monitoring for material properties with residual life estimation of rotor blades for gas turbine engines is proposed. The structure of on-board control and conditionmonitoring system based on the intelligent pyrometer module with the algorithm for calculating the residual life of turbine rotor blades is described. 相似文献
263.
This paper presents a composite model of a flight simulator. This simulator is intended for carrying out investigative tests of flight dynamics imitation models of a hingeless rotor helicopter. A schematic diagram, composition and operation channels of the flight simulator software are presented. A possibility of applying the control lag is estimated. 相似文献
264.
R.?A.?KayumovEmail author I.?Z.?Mukhamedova E.?B.?Tuisina 《Russian Aeronautics (Iz VUZ)》2016,59(4):452-459
This paper considers a beam with a technological longitudinal section on the level of the gravity center of the cross section that is loaded by a vertical concentrated force. We study the structure durability depending on the load amplitude and the initial crack length. 相似文献
265.
266.
昆虫(果蝇)悬停飞行中,翅膀按照特定的拍动方式往复运动,产生非定常高升力维持身体的平衡.研究昆虫高升力机理,需要探索拍动翼运动引发的三维空间非定常流场的特性,尤其是三维空间非定常涡的发展变化过程.本文将氢气泡流动显示技术应用于动态模型实验,定性的观察拍动翼前缘涡(LEV)的发展破裂过程.并利用数字体视粒子图像测速,DSPIV(Digital Steroscopic Particle Image Velocimetry)技术,测得了拍动翼运动瞬时相位和相位平均的三维空间流场信息(速度向量场、截面涡量场、空间涡量场,以及三维空间流线),揭示了拍动翼展向流动的存在,并结合定性和定量方法多角度说明了前缘涡沿展向发展到破裂的流动结构,并说明了侧缘涡与前缘涡的相互影响.测量结果表明:在雷诺数960的情况下,拍动翼运动至相位时,翼面上前缘涡在距翼根约60%展长的位置发生破裂;翼根至破裂点之间,展向流动稳定,指向翼梢;破裂点以后,展向流改变方向,指向翼根. 相似文献
267.
The Electric Antennas for the STEREO/WAVES Experiment 总被引:1,自引:0,他引:1
S. D. Bale R. Ullrich K. Goetz N. Alster B. Cecconi M. Dekkali N. R. Lingner W. Macher R. E. Manning J. McCauley S. J. Monson T. H. Oswald M. Pulupa 《Space Science Reviews》2008,136(1-4):529-547
The STEREO/WAVES experiment is designed to measure the electric component of radio emission from interplanetary radio bursts and in situ plasma waves and fluctuations in the solar wind. Interplanetary radio bursts are generated from electron beams at interplanetary shocks and solar flares and are observed from near the Sun to 1 AU, corresponding to frequencies of approximately 16 MHz to 10 kHz. In situ plasma waves occur in a range of wavelengths larger than the Debye length in the solar wind plasma λ D ≈10 m and appear Doppler-shifted into the frequency regime down to a fraction of a Hertz. These phenomena are measured by STEREO/WAVES with a set of three orthogonal electric monopole antennas. This paper describes the electrical and mechanical design of the antenna system and discusses efforts to model the antenna pattern and response and methods for in-flight calibration. 相似文献
268.
The Plasma and Suprathermal Ion Composition (PLASTIC) Investigation on the STEREO Observatories 总被引:1,自引:0,他引:1
A. B. Galvin L. M. Kistler M. A. Popecki C. J. Farrugia K. D. C. Simunac L. Ellis E. Möbius M. A. Lee M. Boehm J. Carroll A. Crawshaw M. Conti P. Demaine S. Ellis J. A. Gaidos J. Googins M. Granoff A. Gustafson D. Heirtzler B. King U. Knauss J. Levasseur S. Longworth K. Singer S. Turco P. Vachon M. Vosbury M. Widholm L. M. Blush R. Karrer P. Bochsler H. Daoudi A. Etter J. Fischer J. Jost A. Opitz M. Sigrist P. Wurz B. Klecker M. Ertl E. Seidenschwang R. F. Wimmer-Schweingruber M. Koeten B. Thompson D. Steinfeld 《Space Science Reviews》2008,136(1-4):437-486
The Plasma and Suprathermal Ion Composition (PLASTIC) investigation provides the in situ solar wind and low energy heliospheric ion measurements for the NASA Solar Terrestrial Relations Observatory Mission, which consists of two spacecraft (STEREO-A, STEREO-B). PLASTIC-A and PLASTIC-B are identical. Each PLASTIC is a time-of-flight/energy mass spectrometer designed to determine the elemental composition, ionic charge states, and bulk flow parameters of major solar wind ions in the mass range from hydrogen to iron. PLASTIC has nearly complete angular coverage in the ecliptic plane and an energy range from ~0.3 to 80 keV/e, from which the distribution functions of suprathermal ions, including those ions created in pick-up and local shock acceleration processes, are also provided. 相似文献
269.
D. T. Young J. L. Burch R. G. Gomez A. De Los Santos G. P. Miller P. Wilson N. Paschalidis S. A. Fuselier K. Pickens E. Hertzberg C. J. Pollock J. Scherrer P. B. Wood E. T. Donald D. Aaron J. Furman D. George R. S. Gurnee R. S. Hourani A. Jacques T. Johnson T. Orr K. S. Pan S. Persyn S. Pope J. Roberts M. R. Stokes K. J. Trattner J. M. Webster 《Space Science Reviews》2016,199(1-4):407-470
270.
Malini Aggarwal H.P. Joshi K.N. Iyer Y.-S. Kwak J.J. Lee H. Chandra K.S. Cho 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2012
The ionospheric total electron content (TEC) in the northern hemispheric equatorial ionization anomaly (EIA) crest region is investigated by using dual-frequency signals of the Global Positioning System (GPS) acquired from Rajkot (Geog. Lat. 22.29°N, Geog. Long. 70.74°E; Geom. Lat. 14.21°N, Geom. Long. 144.90°E), India. The day-to-day variability of EIA characteristics is examined during low solar activity period (F10.7∼83 sfu). It is found that the daily maximum TEC at EIA crest exhibits a day-to-day and strong semi-annual variability. The seasonal anomaly and equinoctial asymmetry in TEC at EIA is found non-existent and weaker, respectively. We found a moderate and positive correlation of daily magnitude of crest, Ic with daily F10.7 and EUV fluxes with a correlation coefficient of 0.43 and 0.33, respectively indicating an existence of a short-term relation between TEC at EIA and the solar radiation even during low solar activity period. The correlation of daily Ic with Dst index is also moderate (r = −0.35), whereas no correlation is found with the daily Kp index (r = 0.14) respectively. We found that the magnitude of EIA crest is moderately correlated with solar flux in all seasons except winter where it is weakly related (0.27). The magnitude of EIA crest is also found highly related with EEJ strength in spring (r = 0.69) and summer (r = 0.65) than autumn (0.5) and winter (r = 0.47), though EEJ is stronger in autumn than spring. 相似文献