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781.
On the basis of systematic electron temperature measurements onboard the Interkosmos-19 satellite, an experimental global model of electron temperature Te has been constructed; namely, a set of samples representing 10 intervals of measured Te, accompanied by values of the geographic longitude, solar zenith angle, season of the year, Covington index, Dst and Kp, grouped according to the invariant latitude, geomagnetic time and altitude. On the basis of the experimental model, the coefficients of the empirical models for the summer and winter seasons, for geophysically quiet conditions, and for heights of 520, 600, 920 and 1000 km are calculated. For heights of 680, 760 and 840 km with fewer data available, the coefficients are provisional.  相似文献   
782.
The numerical investigation of the impact of time-dependent accelerations (vibrations) on the flow and heat and mass transfer in the melt is carried out for the case of modeling the crystal growth by the floating zone method under conditions of microgravity that exist onboard spacecraft. The effects of the Archimedean buoyancy force and of vibrations of the free surface of fluid are considered separately. When solving the problem of the effect of the vibrations of the free surface of fluid, the previously obtained data were used. It is shown that vibrations of the free surface have a much stronger effect on the processes under consideration than the buoyancy. Some problems that are related to the newly discovered effects are discussed. The use of vibroprotected systems and a rotating magnetic field can help solve these problems. We plan to continue our investigations in future spacecraft experiments, in particular, at the International Space Station, which is under construction at the moment.  相似文献   
783.
Results of rocket experiments on study of plasma flows (PF) artificially injected by sources separated from vehicles and their effect on medium parameters in ionosphere at altitudes 160:230 km are presented.PF were injected comprising lithium ions with velocities 1,2 x 104 m/sec. and cesium-potassium ions with velocities (1,4–1,5)x103 m/sec. Mass flow rate in case of lithium PS is 2 mg/sec, and in case of cesium-potassium PS is 0,2 g/sec. During experiments mass-spectrometer measurements of ion medium content in ranges of different ion masses were held, disturbancies of electric fields with frequencies up to 20 kHz and electron flows with energies 0,7keV, 4,6keV and over 40 keV were controlled at distancies from 150m to (500–600)m between plasma source and scientific equipment.  相似文献   
784.
Data from a complex cytochemical analysis show that the functional state of chromatin and the level of the cell proliferative activity may be reliable cytological criteria for primary structural and functional changes that result in disturbances of plant growth and development. Autoradiographic and cytophotonetric studies made it possible to establish certain differences, induced by fast rotation (50 rev/min) on the clinostat, in the chromatin state and cell reproduction of the pea seedling root meristem for the initial stages of plant development. There were no essential differences for the given parameters under slow (2 rev/min) clinostatic conditions.  相似文献   
785.
This paper presents theoretical methods to determine the gas dynamic and the electrostatic effects due to the interaction caused by a rapidly moving body in the ionosphere. The principles of the methods are derived from the kinetic theory of collision-free plasma. It is shown that the collective behavior of the collision-free plasma makes it possible to use the fluid approach to treat the problems of ionospheric aerodynamics. Various solutions to the system of fluid and field equations that have direct bearing on the ionospheric aerodynamics are presented and discussed. Physical significances of the mathematical results are stressed. Some outstanding unsolved problems in ionospheric aerodynamics are elaborated and discussed.  相似文献   
786.
A small, vibration- and shock-resistant thermoluminescent dosemeter /TLD/ system--named PILLE--was developed at the Health Physics Department of the Central Research Institute for Physics, Budapest, to measure the cosmic radiation dose on board orbital stations. The first on-board measurements with this system were performed /by B. Farkas, the Hungarian astronaut/, on the Salyut-6 space station in 1980. The same instrument was used by other crews in the following years. Doses measured at different sites in Salyut-6 are presented. The dose rates varied from 0.07 to 0.11 mGy.day-1. After the first cosmic measurements, the system was further developed. The minimum detectable dose of the new TLD system is 1 microGy, i.e. less by on order of magnitude than that of the former system. The self-irradiation dose rate of the TLD bulbs is also reduced--by more than one order of magnitude--to 10 nGy.h-1, by the use of potassium-free glass for the bulb envelope. This new type of PILLE TLD system is currently on-board Salyut-7. The dose rates /0.12-0.23 mGy.day-1/ measured in 1983 are presented in detail.  相似文献   
787.
The authors provide an overview of expert systems and how they may effect the development of future defense applications. Military uses of computers are outlined, and expert-systems fundamentals are described. Artificial research and development efforts by the military are examined, and potential military applications are discussed. Expert systems efforts at NASA, by the US Air Force, and for the Strategic Defence Initiative are considered  相似文献   
788.
Circulation and thermal structure for the 90–95 km region is described on the basis of the joint analysis of direct and indirect sounding data. Mean season charts of the 0.001 mb surface were compiled using data from meteor trials, ionospheric drifts, rocket launchings and data of the rotational temperature of hydroxyl emission.  相似文献   
789.
Truly optimal weapon system performance is highly dependent on the level of man-machine cockpit integration resulting from the intelligent application of crew station technologies. Future cockpits will incorporate a wide range of enhancements. Heavy application of artificial intelligence techniques can be expected to encompass the entire spectrum of crew station technologies; from data fusion, to optimized display resource management, to real-time onboard maintenance and fault reporting, and even to the optimization of pilot physiological needs. Emphasis on exploiting applications of the ultimate human resource, the mind, can be expected through the use of biocybernetics; initially to control previously manual and/or automated cockpit functions, and eventually to allow bidirectional communications. Future enhancements can also be expected to improve aircrew performance by allowing the pilot to take full advantage of aircraft maneuvering capability, and to operate effectively in hostile chemical, biological and radiological environments. New high resolution, full color, three dimensional crew station display devices will complement enlarged sensor suites and enhance aircrew situational awareness. Does the pilot really need to see the outside world to fly and fight effectively? Or, can panoramic display techniques, in an encapsulated environment, coupled with 4? steradian sensor coverage, increase performance? This paper strives to illustrate some ``no holds barred' approaches to making future fighter cockpits an ``in-tune' extension of the operator, based on current and projected tactical needs.  相似文献   
790.
Results are given of the study of active regions and flares by a high resolution Mg XI ion spectra obtained aboard rockets and a satellite. It is shown that there is a noticable similarity in the physical conditions in the plasma of active regions and flares. Plasma of both sources consists okf a thermal component with the temperature T ~ 2.?3.106K for active regions and T ~ 1.5?2.5.107K for flares and in both cases of a relatively small number (~ 1–5%) of suprathermal electrons with an energy E ~ 3–6 kT.  相似文献   
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