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951.
J I Gitelson S I Bartsev V V Mezhevikin V A Okhonin 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,31(1):17-24
For systematic human Mars exploration, meeting crew safety requirements, it seems perspective to assemble into a spacecraft: an electrical rocket, a well-shielded long-term life support system, and a manipulator-robots operating in combined "presence effect" and "master-slave" mode. The electrical spacecraft would carry humans to the orbit of Mars, providing short distance (and low signal time delay) between operator and robot-manipulators, which are landed on the surface of the planet. Long-term hybrid biological and physical/chemical LSS could provide environment supporting human health and well being. Robot-manipulators operating in "presence effect" and "master-slave" mode exclude necessity of human landing on Martian surface decreasing the level of risk for crew. Since crewmen would not have direct contact with the Martian environment then the problem of mutual biological protection is essentially reduced. Lightweight robot-manipulators, without heavy life support systems and without the necessity of returning to the mother vessel, could be sent as scouts to different places on the planet surface, scanning the most interesting for exobiological research site. Some approximate estimations of electric spacecraft, long-term hybrid LSS, radiation protection and mission parameters are conducted and discussed. 相似文献
952.
M. Buchvarova P.I.Y. Velinov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
The galactic cosmic rays (GCR) are the main ionization source at altitude of ∼3–35 km in the atmosphere. For high latitude anomalous cosmic ray (ACR) component has also a significant influence on the atmospheric ionization. We propose an empirical model for differential spectra D(E) of galactic and anomalous cosmic rays in energy interval 1 MeV–100 GeV during solar cycle. In the model data are used which cover three solar cycles: 20, 22 and 23. The LEAP87, IMAX92, CAPRICE94, AMS98 and BESS experimental spectra for protons and alpha particles are fitted to the proposed empirical model. The modulated GCR differential spectra are compared with force-field approximation to the one-dimensional transport equation and with solutions of two-dimensional cosmic ray transport equation. For experimental spectra, the calculation of the model parameters is performed by Levenberg–Marquardt algorithm, applied to the special case of least squares. Algorithm that combines the rapid local convergence of Newton–Raphson method with globally convergent method for non-linear systems of equations is applied for theoretically obtained differential spectra. The described programmes are realized in algorithmic language C++. The proposed model gives practical possibility for investigation of experimental data from measurements of galactic cosmic rays and their anomalous component. 相似文献
953.
N. Partamies T.I. Pulkkinen R.L. McPherron K. McWilliams C.R. Bryant E. Tanskanen H.J. Singer G.D. Reeves M.F. Thomsen 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
Solar wind driving can cause a variety of different responses in the magnetosphere. Strong and steady driving during geomagnetic storms may result in sawtooth events. Strong to moderate driving may be followed by either sawtooth events or steady magnetospheric convection (SMC) events. Lower solar wind energy input typically leads to the formation of isolated non-storm substorms. This study uses superposed epoch analysis to reveal the typical properties of these three event groups as well as their similarities and differences. We use IMF and solar wind parameters, as well as ground-based indices (AL, SYM-H, ASY-H, PCN) to examine the level of solar wind driving and its response in the magnetosphere. Our results show that sawtooth events are associated with the strongest ionospheric activity. The subgroups of events during constant solar wind EY show that the key difference between the events is the average solar wind speed. Particularly, the high activity during sawtooth events is driven by high solar wind speed, while the lowest average speed during the SMCs may explain the lack of substorm activity during the steady convection periods. 相似文献
954.
955.
A refined mathematical model of deformation mechanics for a plane curvilinear laminated rod taking into account transverse shear and reduction of package layers is proposed. The numerical algorithms to analyze the stress-strain state and free oscillations of the structure elements being considered are constructed. The refined model proposed provides a basis for extending the range of problems being solved and obtaining some new results. 相似文献
956.
D. I. Miftakhutdinov I. S. Rizaev M. P. Shleimovich 《Russian Aeronautics (Iz VUZ)》2017,60(4):542-550
In this paper, detection of objects in airborne systems of unmanned aerial vehicles using information about changes in the image of the terrain is considered. A proposed technique includes initial detection of objects by the level of local contrast over the field of the image misalignment function, calculation of the amplitude characteristics of objects, and their further filtering by a set of calculated values of characteristics. 相似文献
957.
The application of artificial neural networks for aircraft motion control, in particular, for creation of nonlinear algorithms of the aircraft remote control system (RCS) is considered. Aircraft as a control object is represented as a multidimensional nonlinear dynamic system and nonlinear control methods are used to operate this system. The control loop is constructed using the method of inverse dynamics based on the feedback linearization principle. The nonlinear control law is represented as a neural network being learned (adjusted) by recorded or incoming measurements of motion parameters. Synthesis and testing of neural network control algorithms is performed with the fully nonlinear mathematical model of a maneuverable aircraft for three control channels. Simulation results of the closed system are presented. 相似文献
958.
V. N. Oraevsky Yu. Ya. Ruzhin V. S. Skomarovsky V. G. Korobeinikov A. I. Kashirin V. I. Khryukin 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1992,12(12):105-107
Results of a combination of radio-crossing and in situ measurements of plasma density in an artificial plasma “bubble” in the ionosphere are presented. Shaped — charge barium injection was made at short distance (≤50 m) to plasma diagnostics on the rocket. After injection the rocket passed through expanding plasma shell. Plasma density depletion inside was more than one order and plasma enhancements on the boundary about 3–5 times that of background. When the rocket passed the shell and went away by 2.1 km an abrupt drop of telemetry signal level (≤ 65 dB) was registered though plasma density was not more than 3×103sm−3. An estimation of high frequency signal refraction on the plasma shell is in good accordance with refraction data of geostationary satellite signals on equatorial bubbles. 相似文献
959.
I.N. Myagkova M.I. PanasyukL.L. Lazutin E.A. MuravievaL.I. Starostin T.A. IvanovaN.N. Pavlov I.A. RubinshteinN.N. Vedenkin N.A. Vlasova 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
The Russian microsatellite “Universitetskiy-Tatiana” was launched on Jan. 20, 2005 and was both a scientific and educational mission. Its two main aims were declared as: (1) monitoring of the energetic particles dynamics in the near-Earth space environment after solar events and during quiet times, (2) educational activities based on experimental data obtained from the spacecraft. In this paper observations acquired during Dec. 5–16, 2006, known as “Solar Extreme Events 2006”, were analyzed. The “Universitetskiy-Tatiana” microsatellite orbit permits one to measure both solar energetic particle dynamics, variations of the boundary of solar particle penetration, as well as relativistic and sub-relativistic electrons of the Earth’s outer radiation belt during and after magnetic storms. Both relativistic electrons of the Earth’s outer radiation and solar energetic particles are an important source of radiation damage in near-Earth space. Therefore, the presented experimental results demonstrate the successful application of a small educational spacecraft both for scientific and educational programs. 相似文献
960.
L Kostina I Anikeeva E Vaulina 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,4(10):65-70
The experiments with air-dried Crepis capillaris seeds aboard the Soyuz 16 spaceship and the orbital stations Salyut 5, 6, 7 have revealed an increase in the frequency of aberrant cells in seedlings grown from flight-exposed seeds during the flight (experiment) and after the flight on Earth (flight control) as compared to the ground-based control. The increase in seedlings grown during the flight is more significant than in the flight control. During the flight Arabidopsis thaliana developed from cotyledons to the flowering stage. Analysis of seeds setting on these plants after the flight has shown a reduction in the fertility of these plants and an increase in the frequency of recessive mutants ("Light block-1"). An increased frequency of mutants was also retained in the progeny of plants which had passed through a complete cycle of development during the flight ("Fiton-3"). Suppression of embryo viability was observed in all experiments and expressed itself in reduced germinating ability of seeds from the exposed plants and in the early death of seedlings. Damages resulting from chromosome aberrations are eliminated in the first postflight generation and damages resulting from gene mutations and micro-aberrations are preserved for a longer time. 相似文献