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In article the opportunity of use strapdown inertial navigation system (SINS) on the base of fiber-optic gyroscopes and quartz accelerometers corrected from star sensors and satellite navigation equipment (SNE) for perspective interplanetary spacecrafts motion control on phases of interplanetary trajectory insertion, trajectory correction, and braking during transition to Mars orbit is investigated. Results of onboard control complex accuracy characteristics estimation are presented at the given dynamic spacecraft scheme which is taking into account the liquid oscillations in tanks and structure elements elasticity. At modelling the errors of measuring devices installation, errors of SINS initial alignment and instrumental errors of SINS sensitive elements, variation of control engines parameters were taken into account. The structure of the developed complex of imitation modelling of interplanetary spacecraft controlled motion is resulted. Estimations of active flight legs realization accuracy were received by a method of statistical modelling of spacecraft controlled motion  相似文献   
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The role of calcium ions in cytological effects of hypogravity   总被引:1,自引:0,他引:1  
Electron-cytochemical and biochemical methods made it possible to reveal certain differences in ATPase activity stimulation by calcium ions in root apex cells of pea seedlings and moss protonema Funariahygrometrica grown under stationary and slow clinostatic (2 rev/min) conditions. It was showed that under clinostatic conditions in comparison with the control variant the ATPase activity decreases in plasmalemma. The protein content in the plasmalemma fraction was also twice as low under these conditions. The root apex cells of the pea seedlings grown under spaceflight conditions were found to contain high concentrations of membrane-bound calcium. The data obtained are discussed in relation to problems of possible mechanisms of disturbance in calcium balance and the system of active calcium ion transport through plasmalemma under hypogravity.  相似文献   
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Earlier latitudinal distribution models of zonal winds were developed mainly along the 80°W meridian [1, 2]. In this paper an attempt is made to take into account longitudinal differences in zonal and meridional wind distributions. These are considerable in winter prediods.  相似文献   
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This paper analyses Russia's view of its involvement in international space cooperation and the Western concerns associated with this. In the current economic and political situation the Russian administration and space industry are eager to take part in all kinds of international space activity, which is seen as an opportunity to sustain the country's scientific and technological potential. Russia claims a fair share in both commercial space operations and joint space development programmes, appropriate to its capabilities as the world's number two space power. Western concerns about Russian interference in its policy and the problems involved in dealing with Russia should be solvable and are less dangerous than reverting to a situation of confrontation.  相似文献   
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Research in cellular reproduction, differentiation and vital activity, i.e. processes underlying the development and functioning of organisms, plants included, is essential for solving fundamental and applied problems of space biology. Detailed anatomical analysis of roots of higher plants grown on board the Salyut 6 orbital research station show that under conditions of weightlessness for defined duration mitosis, cytokinesis and tissue differentiation in plant vegetative organs occur essentially normally. At the same time, certain rearrangements in the structural organization of cellular organelles--mainly the plastid apparatus, mitochondria, Golgi apparatus and nucleus--are established in the root meristem and cap of the experimental plants. This is evidence for considerable changes in cellular metabolism. The structural changes in the subcellular level arising under spaceflight conditions are partially absent in clinostat experiments designed to simulate weightlessness. Various clinostatic conditions have different influences on the cell structural and functional organization than does space flight. It is suggested that alterations of cellular metabolism under weightlessness and clinostatic conditions occur within existing genetic programs.  相似文献   
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This paper surveys the status of Russian space activities in terms of budget, operational satellite systems, workforce and industrial capabilities. There is inequality between companies and particularly between various tiers of cooperation in production. In the current situation international cooperation, both in the form of joint non-commercial ventures and integration into the global space market, is considered vital for sustaining national space capabilities.  相似文献   
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Methods of calculation of interhemispheric and longitudinal differences are discussed. It is noted that in models one should take into account the solar activity influence. Network rocket sounding accuracy, devices and technique compatibility are analysed.  相似文献   
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