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991.
A.M. Unewisse 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2021,67(3):1026-1038
Mean night-time peak power, Doppler shift and Doppler width of spread Doppler clutter (SDC) received by a high frequency backscatter radar located at Alice Springs, Australia from 2000 to 2018 is presented as a function of azimuth, sunspot number, time of year and frequency. The sampled region covers 90 degrees from West to North and includes the northern and southern equatorial anomalies.SDC peak power diminished across all azimuths during the winter solstice from around May to August (local winter) coinciding with the global decrease in F layer density due to the annual non-seasonal F2 anomaly but was generally constant during the equinoxes. In contrast, SDC Doppler width and inbound Doppler shift both increased during the equinoxes and exhibited azimuthal dependence related to the eastward equatorial plasma drift.SDC peak power increased with increasing sunspot number with frequency dependence during winter but not summer. Inbound Doppler shift and Doppler width increased with increasing sunspot number during equinox but not solstice with a strong dependence on azimuth and a weak dependence on frequency. 相似文献
992.
G. P. Anshakov A. I. Belousov A. V. Sedel’nikov A. S. Gorozhankina 《Russian Aeronautics (Iz VUZ)》2018,61(3):347-354
The influence of various control systems of the orbital motion of a technological spacecraft on the level of microacceleration of its internal environment is simulated. Conclusions are drawn about the effectiveness of control systems with different actuators for realization of certain gravitationally sensitive processes onboard a spacecraft. 相似文献
993.
V. A. Sadovnichii M. I. Panasyuk V. M. Lipunov A. V. Bogomolov V. V. Bogomolov G. K. Garipov E. S. Gorbovskoy D. S. Zimnukhov A. F. Iyudin M. A. Kaznacheeva V. V. Kalegaev P. A. Klimov A. S. Kovtukh V. G. Kornilov N. V. Kuznetsov I. A. Maksimov S. K. Mit V. I. Osedlo V. L. Petrov M. V. Podzolko E. P. Popova A. Yu. Poroykov I. A. Rubinstein K. Yu. Saleev S. I. Svertilov V. I. Tulupov B. A. Khrenov V. V. Chazov A. S. Chepurnov Ya. A. Shtunder A. N. Shustova I. V. Yashin 《Cosmic Research》2018,56(6):488-497
994.
Alireza A. Ardalan Iraj Jazireeyan Naser Abdi Mohammad-Hadi Rezvani 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2018,61(6):1537-1545
Performance of SARAL/AltiKa mission has been evaluated within 2016 altimeter calibration/validation framework in Persian Gulf through three campaigns conducted in the offshore waters of Sajafi, Imam Hassan and Kangan Ports, while the altimeter overflew the passes 470, 111 and 25 on 13 Feb, 7 March and 17 June 2016, respectively. As the preparation, a lightweight buoy was equipped with a GNSS receiver/choke-ring antenna and a MEMS-based IMU to measure independent datasets in the field operations. To obtain accurate sea surface height (SSH) time series, the offset of the onboard antenna from the equilibrium sea level was predetermined through surveying operations as the buoy was deploying in the onshore waters of Kangan Port. Accordingly, the double-difference carrier phase observations have been processed via the Bernese GPS Software v. 5.0 so as to provide the GNSS-derived time series at the comparison points of the calibration campaigns, once the disturbing effects due to the platform tilt and heave have been eliminated. Owing to comparing of the SSH time series and the associating altimetry 1?Hz GDR-T datasets, the calibration/validation of the SARAL/AltiKa has been performed in the both cases of radiometer and ECMWF wet troposphere corrections so as to identify potential land contamination. An agreement of the present findings in comparison with those attained in other international calibrations sites confirms the promising feasibility of Persian Gulf as a new dedicated site for calibration/validation of ongoing and future altimetry missions. 相似文献
995.
Yu. M. Ignatkin P. V. Makeev V. I. Shaidakov A. I. Shomov 《Russian Aeronautics (Iz VUZ)》2018,61(3):396-403
The research is conducted of aerodynamic performance of the Mi-8 helicopter main rotor in the hover state and the vertical descent state, including vortex ring states (VRSs). Total and distributed aerodynamic performance, wake patterns, and main rotor flow patterns are calculated. The findings and results were compared with those provided by other researchers. 相似文献
996.
A. V. Streltsov J.-J. Berthelier A. A. Chernyshov V. L. Frolov F. Honary M. J. Kosch R. P. McCoy E. V. Mishin M. T. Rietveld 《Space Science Reviews》2018,214(8):118
Active ionospheric experiments using high-power, high-frequency transmitters, “heaters”, to study plasma processes in the ionosphere and magnetosphere continue to provide new insights into understanding plasma and geophysical proceses. This review describes the heating facilities, past and present, and discusses scientific results from these facilities and associated space missions. Phenomena that have been observed with these facilities are reviewed along with theoretical explanations that have been proposed or are commonly accepted. Gaps or uncertainties in understanding of heating-initiated phenomena are discussed together with proposed science questions to be addressed in the future. Suggestions for improvements and additions to existing facilities are presented including important satellite missions which are necessary to answer the outstanding questions in this field. 相似文献
997.
Valentin A. Shuvalov Dmitry N. Lazuchenkov Nikolai B. Gorev Galina S. Kochubei 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2018,61(1):355-366
Using a cylindrical Langmuir probe and the authors’ proprietary two-channel pressure transducer, ionospheric plasma parameter distributions along the orbit of the Sich-2 satellite (Ukraine, 2011–2012) were measured. This paper is concerned with identifying the space–time location of ionospheric plasma disturbance sources, including the epicenters of actual earthquakes (before or during the satellite flyover) and incipient earthquakes on the subsatellite track, from the measured distributions of the electron density and temperature and the neutral particle temperature along the satellite orbit. To do this, the measured ionospheric plasma parameter distributions are connected to the coordinates on the subsatellite track.It is shown that local disturbances in the electron density and temperature and neutral particle temperature distributions in the satellite orbit in the ionosphere may serve as indicators of seismic activity on the subsatellite track. The epicenters of incipient earthquakes may be set off from other plasma parameter disturbance sources associated with seismic activity using information provided by special monitoring and survey centers that monitor the current seismic situation. 相似文献
998.
The present study investigated cognitive map development in multilevel built environments. Three experiments were conducted in complex virtual buildings to examine the effects of five between-floor structural factors that may impede the accuracy of humans’ ability to build multilevel cognitive maps. Results from Experiments 1 and 2 (of three experiments) revealed that difficulties in developing multilevel cognitive maps are not solely caused by the z-axis offset, as is suggested in the literature, but are due to the factorial combination of a between-floor overlap and a z-axis offset. Results from Experiment 2 showed that this process becomes substantially more difficult when the reference directions between different floors have an angular offset from each other. Finally, results from Experiment 3 demonstrated that confusing between-floor heading shifts in aligned buildings did not make it reliably harder to build multilevel cognitive maps. The implications of these findings are discussed in terms of theories of mental representations in multilayered three-dimensional spaces, as well as for architectural design. 相似文献
999.
S.A. Demin Y.A. Nefedyev A.O. Andreev N.Y. Demina S.F. Timashev 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2018,61(2):639-644
The analysis of turbulent processes in sunspots and pores which are self-organizing long-lived magnetic structures is a complicated and not yet solved problem. The present work focuses on studying such magneto-hydrodynamic (MHD) formations on the basis of flicker-noise spectroscopy using a new method of multi-parametric analysis. The non-stationarity and cross-correlation effects taking place in solar activity dynamics are considered. The calculated maximum values of non-stationarity factor may become precursors of significant restructuring in solar magnetic activity. The introduced cross-correlation functions enable us to judge synchronization effects between the signals of various solar activity indicators registered simultaneously. 相似文献
1000.
A. N. Sabirzyanov A. I. Glazunov A. N. Kirillova K. S. Titov 《Russian Aeronautics (Iz VUZ)》2018,61(2):257-264
Multiparameter studies of the discharge coefficient dependence on the nozzle geometry and the presence of a condensed phase in combustion products were performed. The simulation results obtained satisfactorily agree with the well-known generalized data. The modern computational fluid dynamics methods were shown to be able to refine the generalized empirical relations. 相似文献