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191.
The DB-8 detectors of the ISS radiation monitoring system (RMS) have operated almost continuously onboard the ISS service module since August 2001 till December 2014. The RMS data obtained were used for the daily monitoring of the radiation environment aboard the station. This paper considers the technique of RMS data analysis that allows one to distinguish the contributions of galactic cosmic rays and the Earth’s inner radiation belt to the daily dose based on the dosimetry data obtained as a result of the station’s passage in areas of the highest geomagnetic latitudes. The paper presents the results of an analysis of the dosimetry data based on this technique for 2005–2011, as well as a comparison with similar results the authors obtained previously using the technique based on an analysis of the dosimetry data obtained during station passages in the area of the South Atlantic Anomaly. 相似文献
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D. V. Nedel’ko 《Russian Aeronautics (Iz VUZ)》2016,59(3):297-302
A method of determining the maximum permissible values for diagnostic signs, being an integral part of health and usage monitoring systems (HUMS) of the helicopter transmission units, has been developed based on a probabilistic approach. 相似文献
196.
A. Guharay P.P. Batista R.A. Buriti 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2021,67(10):3125-3133
An evident signature of a least studied quasi-90-day oscillation is found in the winds and tides in the MLT from an equatorial station, São João do Cariri (7.4°S, 36.5°W). The oscillation is found to appear mainly in certain intervals with small but appreciable seasonal (fourth harmonic of annual oscillation) contribution. The maximum amplitude of the oscillation is found to be around 10 m/s in the zonal wind. The enhancement peak of the oscillation exhibits downward movement indicating a plausible role of upward moving waves/tides in carrying its imprint from below to the MLT. Similar oscillation feature in the tropospheric zonal wind and ozone may imply its lower atmospheric origin as a component of the intraseasonal oscillation (ISO) that moves upward by modulating the tides. Subsequently, the propagating tides (mainly semidiurnal) are enhanced by the ozone in the stratosphere through absorption of solar UV radiation and finally manifest the oscillation in the MLT. Consistency of the present findings with the past investigations are observed in some aspects of the oscillation, whereas existing mismatches in others are believed to be due to geophysical variability depending on space and time among various locations on the globe. 相似文献
197.
A.K. Sharma O.B. Gurav Anindya Bose H.P. Gaikwad G.A. Chavan Atanu Santra S.S. Kamble R.S. Vhatkar 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2019,63(10):3131-3138
Indian Space Research Organization (ISRO) has developed an indigenous system named Indian Regional Navigation Satellite System (IRNSS) or NavIC (Navigation with Indian Constellation), that consists of 7 satellites and transmits navigation signal in L and S bands. ISRO, for validation of the system, has installed many IGS (IRNSS/GPS/SBAS) receivers scattered over the Indian region. Using preliminary data from two geographically widely separated stations over India, this paper presents the results on studies on parameters of IRNSS signal quality and discusses how these parameters may be used to study the ionospheric behavior over the Indian region. The results show the importance and advantages of using IRNSS data for such studies. 相似文献
198.
Based on an integrated approach, we solve the optimization problem for energy content and weight-dimensional characteristics of the electric servo drive by synthesis of structure and analysis of characteristics for different power supplies. The generalized power supply model, developed for different power supply of drive control systems, is given. 相似文献
199.
E. O. Ariskin A. V. Nikitin V. V. Soldatkin V. M. Soldatkin 《Russian Aeronautics (Iz VUZ)》2015,58(4):454-460
The problem and features of measuring the speed and the direction angle of the wind vector relative to the longitudinal helicopter axis during parking, starting and takeoff-landing modes by onboard means are considered. The construction principles, information processing algorithms and advantages of onboard system for measuring the wind vector parameters based on ion-beacon and aerometric measuring channels, are disclosed. 相似文献
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