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141.
T. P. Borisevich G. N. Il’in A. N. Korzhavin N. G. Peterova N. A. Topchilo A. A. Shpitalnaya 《Cosmic Research》2004,42(6):561-570
We present the results of spectral and polarization observations of two large sunspot groups, NOAA 0484 and NOAA 0486 + 0488, which determine high solar activity in October–November 2003. The observations are made with the Large Pulkovo Radio Telescope (LPRT) in the range 2.7–20 cm, the one-dimensional (E-W) resolution of observations being 1–6 arc min, respectively. The main characteristics of the corona radio emission above these active regions are measured, allowing us to follow their dynamics during the entire period of their existence on the solar disk with a period of one day. The analysis of the obtained results is presented from the point of view of the well-known Tanaka-Enome criterion [1–2] (on the basis of this criterion one can predict strong flares from characteristics of radio emission of an active region in quasi-quiet state). Using the activity in October–November 2003 as an example, we demonstrate the capabilities of a new method for estimating the level of solar activity. It was developed on the basis of long-term observations of the Sun by LPRT [3].Translated from Kosmicheskie Issledovaniya, Vol. 42, No. 6, 2004, pp. 585–594.Original Russian Text Copyright © 2004 by Borisevich, Ilin, Korzhavin, Peterova, Topchilo, Shpitalnaya. 相似文献
142.
Gillmann Cedric Way M. J. Avice Guillaume Breuer Doris Golabek Gregor J. Höning Dennis Krissansen-Totton Joshua Lammer Helmut O’Rourke Joseph G. Persson Moa Plesa Ana-Catalina Salvador Arnaud Scherf Manuel Zolotov Mikhail Y. 《Space Science Reviews》2022,218(7):1-21
Space Science Reviews - The BepiColombo Environment Radiation Monitor (BERM) on board the European Space Agency’s Mercury Planetary Orbiter (MPO), is designed to measure the radiation... 相似文献
143.
A study is made to define a procedure of cooperative processing of goniometric and range difference measurements in multilateral system of passive radiolocation. As a result, we worked out the computational algorithms, which implement this procedure. The accuracy characteristics are estimated. 相似文献
144.
V. A. Afanas’ev G. L. Degtyarev V. I. Kiselev A. S. Meshchanov 《Russian Aeronautics (Iz VUZ)》2016,59(3):324-330
We resolve a problem how to control the longitudinal angular motion of flight vehicles (FV) having a system to displace the center of mass in the transverse direction. A structure is determined and a control law is established to start up and shutdown the engines. Formulas to determine the control parameters are obtained. 相似文献
145.
146.
The results of numerical studying the influence of inertially deposited particles of the condensed phase on the efficiency
of a gas screen in a supersonic dispersed flow are presented. The possibility of realizing the Leont’ev paradox on the adiabatic
surface region streamlined by a supersonic dispersed flow, involved in attaining the temperature of the surface being protected
smaller than the coolant temperature on the permeable section of screen formation is specified. 相似文献
147.
A technique for constructing the observers to evaluate a linear combination of state variables is considered. We propose an algorithm for analytical synthesis of the minimum-order functional observers based on the nondegenerate transformation of the object model in the state space using the matrix canonization technology. The applicability limits of the technique and the conditions of problem solvability are defined. 相似文献
148.
V. N. Kuril’chik 《Cosmic Research》2011,49(6):500-503
The auroral kilometric radio emission (AKR) is the most powerful sporadic radio emission of the terrestrial magnetosphere.
It was discovered in 1965 by Soviet scientists in the experiment onboard the Electron-2 satellite [1]. The AKR still continues to stay an object of a large interest and detailed study (see, for example, a review
by Gurnett [2]). The mechanism of cyclotron maser instability proposed by Wu and Lee [3] is a commonly accepted mechanism
of AKR generation. We have demonstrated the presence of powerful AKR simultaneously in both hemispheres of the Earth in the
period from August 1995 to August 1997, including summer-winter periods, on particular examples of registration of this emission
in [4] where the directivity and mechanism of the emission were studied. Since in that period AKR was observed in the vicinity
of perigees of the satellite orbit in both hemispheres almost at every orbit (3.8 days), we have a possibility to trace in
more detail the changes in the emission power from one orbit to another in 1996 during a deep minimum of solar activity. 相似文献
149.
I. V. Bychkov V. A. Voronov E. I. Druzhinin R. I. Kozlov S. A. Ul’yanov B. B. Belyaev P. P. Telepnev A. I. Ul’yashin 《Cosmic Research》2014,52(2):145-152
The paper presents the second part of the results of search studies for the development of a combined system of high-precision stabilization of the optical telescope for the designed Spectr-UF international observatory [1]. A new modification of the strict method of the synthesis of nonlinear discrete-continuous stabilization systems with uncertainties is described, which is based on the minimization of the guaranteed accuracy estimate calculated using vector Lyapunov functions. Using this method, the synthesis of the feedback parameters in the mode of precise inertial stabilization of the optical telescope axis is performed taking the design nonrigidity, quantization of signals over time and level, and errors of orientation meters, as well as the errors and limitation of control moments of executive engine-flywheels into account. The results of numerical experiments that demonstrate the quality of the synthesized system are presented. 相似文献
150.
Two criteria for the applicability of a gas-dynamic approximation of continuous medium to describing the dispersion of combustion products of rocket propellants at high altitudes are formulated. Related numerical estimates are given for different launch vehicles and one upper stage with fairly extended boost phases. The use of a continuous medium approximation is shown to have a clear altitude restriction. 相似文献