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971.
The influence of zonal and meridional components of the neutral wind under anthropogenic impacts of water molecules on the ionospheres electron concentration distributed along a magnetic field tube is considered. Computer simulation method based on a mathematical model of the F2 region along a field tube is used.Translated from Kosmicheskie Issledovaniya, Vol. 43, No. 1, 2005, pp. 76–80.Original Russian Text Copyright © 2005 by Medvedev, Ishanov, Zenkin. 相似文献
972.
Singh S.N. Bhattacharya K.C. Ramaswamy S. Rao C.S. 《IEEE transactions on aerospace and electronic systems》1975,(5):905-907
It is shown that when the gyro spin vector is in opposition to the spin vector of the vehicle, the output differential equation of the gyro becomes unstable for large vehicle spin values. When the gyro is used with its spin vector along the spin vector of the vehicle, the steady-state response of the gyro is a nonlinear function of the roll rate of the vehicle. 相似文献
973.
S. Hayakawa 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(13):145-148
A new burst mode of MXB 1730 - 335, the rapid burster, as discovered by Hakucho in August 1979, is characterized by a train of long X-ray bursts whose behaviour is dictated by the accretion rate. In this mode the burst luminosity reaches the Eddington limit, so that the X-ray pressure controls the accretion from a reservoir in the magnetopause and accretion columns in the polar regions explain general features of the rapid burster observed in August 1979. 相似文献
974.
Kabasawa S. Morinaga N. Namekawa T. 《IEEE transactions on aerospace and electronic systems》1980,(5):712-720
A general expression of the error probability on an M-ary coherent phase-shift-keyed (MCPSK) signal purturbed by a noisy reference carrier, multiple interferences, and additive Gaussian noise is presented taking into account the frequencey divider in the carrier recovery circuit. First, a new expression for the probability density function (pdf) of the phase of a composite wave of signal, multiple interferences, and additive Gaussian noise is derived. Then this result and a pdf of the phase error modified from the Tikhonov distribution are used to obtain the erro probability of an MCPSK detector. In addition, the comparison between the error probabilities with and without the frequency divider is given, and it is found that the estimation is more pessimistic when the frequency divider is included. 相似文献
975.
Yu.V. Kushnerevsky S.A. Pulinets 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(2):97-101
Experimental results of the Wave measurements over frequency range 0.1–5.0 MHz during the second launch of the ARAKS Experiment (15.02.75) are reported. The differences between the results of the first and the second launches are discussed. 相似文献
976.
G.I. Sivashinsky 《Acta Astronautica》1976,3(11-12)
The radius of curvature of a steady distorted flame often turns out to be considerably larger than the width of the thermal structure of the flame. Thus, even under finite deformations of the flame, its structure remains quasi-one-dimensional. This property enables the propagation velocity of a distorted flame front (relative to the gas) to be determined explicitly as a function of the hydrodynamic field and the physico-chemical parameters of the gaseous mixture. With the aid of this relationship one can try to determine the shape of the front in a model which is external with respect to the flame structure and treats the flame as a density jump in an ideal incompressible fluid. As applications, we consider (1) the structure of a Bunsen cone, (2) the extinction of a flame in a divergent flow and (3) the propagation velocity of a corrugated flame. 相似文献
977.
The major radio aids to air navigation are listed. Underlined are those whose signal format is standardized by the International Civil Aviation Organization (ICAO) and they have now all been the subject of the IEEE Aerospace and Electronic Systems Society Pioneer Award, as follows: airborne direction finder/nondirectional beacon (ADF/NDB), Busignies and Moseley, 1959; VHF omnidirectional range (VOR), Stuart, 1962; instrument landing system (ILS), Kramar 1964, Alford 1965; air traffic control radar beacon system (ATCRBS), Williams, Bowden, and Harris, 1973; distance measuring equipment (DME), Dodington, 1980. A brief history of the development of the distance measuring equipment, which also formed the basis for an IEEE National Aerospace Electronics Conference luncheon address, is given. 相似文献
978.
979.
Space radiation dosimetry with active detections for the scientific program of the second Bulgarian cosmonaut on board the Mir space station. 总被引:1,自引:0,他引:1
J V Dachev TsPMatviichuk YuN Semkova R T Koleva B Boichev P Baynov N A Kanchev P Lakov P T Ivanov YaJTomo V M Petrov V I Redko V I Kojarinov R Tykva 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1989,9(10):247-251
A dosimetry-radiometry system has been developed at the Space Research Institute of the Bulgarian Academy of Science to measure the fluxes and dose rates on the flight of the second Bulgarian cosmonaut. The dosimetry system is designed for monitoring the different space radiations, such as solar cosmic rays, galactic cosmic rays and trapped particles in the earth radiation belts. The system consists of a battery operated small size detector unit and a "read-write" and telemetry microcomputer unit. The sensitivity of the instrument (3.67 x 10(-8) rad/pulse) permits high resolution measurements of the flux and dose rate along the track of the Mir space station. We report our initial results for the period of the flight between the 7th and 17th June 1988. 相似文献
980.