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In order to observe exoplanets we propose a space-based achromatic stellar coronagraph combined with a 0.8–1.5 m telescope. We develop an achromatic common path interferometer for observing an exoplanet (a faint off-axis source) on the background of a hoste star (bright axial source). An image of the star and its copy acquire an achromatic phase shift by 180° and interfere in antiphase. The achromatic phase shift is caused by geometric phase in the scheme of a three-dimensional interferometer. The interference process divides spatially the dark and light fields of the star image redirecting them to the opposite sides of a beam splitter. The interference process does not weaken the image of a planet, with equal intensities it is redirected to both sides of a beam splitter. The suggested scheme of common path interferometer ensures mechanical stability. The background signal is experimentally demonstrated to be reduced by six orders of magnitude.  相似文献   
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Mechanisms of formation of cyclonic vortices in the tropical atmosphere of the Earth are investigated in the intratropical zone of convergence using numerical simulation made with the complete system of equations of gas dynamics taking into account transport of infrared radiation, phase transitions of water vapor into microdrops of water and ice particles, and sedimentation of these drops and ice particles in the field of gravity force. Observational data on the structure of dominant air streams, which are formed in the intratropical zone of convergence over the North Atlantic in the periods of its highest thermodynamic intensity and instability, are used in the initial and boundary conditions of the model. Formation of cyclonic vortex flows is obtained numerically at sufficiently strong bending of the intratropical zone of convergence. The results of numerical modeling are compared with the data of satellite microwave monitoring: global radio thermal fields of the Earth from the electronic collection GLOBAL-Field allowing one to study the structure of atmospheric motions in a wide range of space-time scales.  相似文献   
3.
Relativistic electrons in the slot region of Earth's electron radiation belt are studied using CORONAS-I satellite data obtained in March–May 1994. The strong shifts of the slot latitudinal location (from L≈3 to L≈2) were found. These shifts are associated with the Earth crossing sector boundaries formed by sector corotating structures of the solar wind and interplanetary magnetic field (IMF). The quantitative analysis of the relationship between properties of the slot region and values of the solar wind and IMF parameters was undertaken. The empirical model of the slot region dynamics was developed by means of Artificial Neural Network (ANN).  相似文献   
4.
Some ways of the decision of a problem of the radioelectronic equipment electromagnetic compatibility dealing with the creation of new materials effectively interacting with electromagnetic irradiation (EMI) and special constructions based on it are designated. There are presented some examples of last generation radioshielding and radioabsorbing materials of various classes with interesting both radiophysics and operational characteristics, have been design by the authors. To achieve a good price/quality ratio and high efficiency, it is a necessary choice relevant type of microwave absorber material and construction for the current task, depending on concrete radiophysical and operational conditions of application. That's why "Radiostrim" company spent parallel development of several classes of materials. Each type of the listed materials possesses the advantages and disadvantages, accordingly, has the various cost price. The main concept of activity of our enterprise - to provide all spectrums of the microwave absorbers potentially required at the present stage development both in technological, and in financial, and industrial aspect.  相似文献   
5.
The Institute of Biomedical Problems (IBMP) is the lead institution of the Russian Federation in the area of space biology and medicine. It has successfully implemented a set of innovation-based activities and projects to develop and introduce promising space products and technologies into the practices of Earth health care.  相似文献   
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Using numerical simulation, a mechanism of formation of polar cyclones in the region of location of the arctic front in the winter troposphere of the Northern Hemisphere is studied. The simulation was performed with the help of the complete system of gas dynamics equations taking into account the transport of infrared radiation, phase transitions of water vapor into micro-drops of water and ice particles, and with allowance made for sedimentation of these drops and ice particles in the gravity field. In the initial and boundary conditions of the model, observational data on the structure of dominating air flows in the region of the arctic front over Norwegian Sea in January are used. Formation of large-scale cyclonic vortex flows in 15–20 hours at the presence of a bend of the central line of the shear flow in the arctic front 500–600 km long with northward or southward deviations by 100 km and more is obtained numerically. On the basis of the simulation results, a method of short-term forecast of formation and motion of polar cyclones is suggested.  相似文献   
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