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531.
532.
V. G. Fainshtein 《Cosmic Research》2007,45(5):384-392
A positive correlation is shown to exist between the angular sizes (in the sky plane) of eruptive prominences and/or post-eruptive arcades and coronal mass ejections (CMEs) associated with them. New regularities are found that characterize the relationship between the latitude of eruptive prominences (post-eruptive arcades) and the latitude position of CMEs associated with them in the field of view of a coronagraph. An interpretation of these regularities is given. 相似文献
533.
534.
Lobanov V.S. Tarasenko N.V. Shulga D.N. Zboroshenko V.N. Fedotov V.P. 《Aerospace and Electronic Systems Magazine, IEEE》2007,22(4):23-29
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
535.
536.
We describe a numerical integral-projection method used by the authors for the approximate solution of systems of interrelated two-dimensional linear boundary-value problems in mechanics of composite shell systems. The method is based on discretization in each shell substructure of a two-dimensional problem along one of coordinates using a projection-grid variant of the Galerkin-Petrov method and its subsequent transformation to a system of ordinary differential equations; by integration and introduction of sought functions as unknown derivatives, the system is reduced to a system of integral equations being solved by the method of mechanical quadratures. The method is characterized by the fact that its application requires no additional conditions of conformity with discretization parameters of substructures being mated. 相似文献
537.
D P Hader M Lebert P Richter 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1998,21(8-9):1277-1284
Gravitactic orientation in the flagellate Euglena gracilis is mediated by an active physiological receptor rather than a passive alignment of the cells. During a recent space flight on the American shuttle Columbia the cells were subjected to different accelerations between 0 and 1.5 x g and tracked by computerized real-time image analysis. The dependence of orientation on acceleration followed a sigmoidal curve with a threshold at < or = 0.16 x g and a saturation at about 0.32 x g. No adaptation of the cells to the conditions of weightlessness was observed over the duration of the space mission (12 days). Under terrestrial conditions graviorientation was eliminated when the cells were suspended in a medium the density of which (Ficoll) equaled that of the cell body (1.04 g/ml) and was reversed at higher densities indicating that the whole cytoplasm exerts a pressure on the respective lower membrane. There it probably activates stretch-sensitive calcium specific ion channels since gravitaxis can be affected by gadolinium which is a specific inhibitor of calcium transport in these structures. The sensory transduction chain could involve modulation of the membrane potential since ion channel blockers, ionophores and ATPase inhibitors impair graviperception. 相似文献
538.
P.K. Taylor 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1985,5(6):225-236
The potential of satellite measurements to define the ocean surface fluxes of heat, water and momentum is reviewed. Only surface stress and possibly rainfall can be directly estimated, latent heat flux may be available through parametrization, sensible heat flux cannot be obtained. Each of the radiative flux components may be estimated including possibly the downward longwave flux. However it is emphasised that, even for those fluxes which can be obtained, improvements in absolute accuracy of the monthly mean, area averaged values are required. Sampling by a single polar orbiting satellite is likely to be at best, marginally adequate. In most cases a pair of satellites will be needed.Calibration and continued validation of the satellite data using improved data will be necessary, and a combination of measurement systems will have to be used if the accuracy requirements are to be approached. Provision of data systems should be considered as part of the planning for future satellite missions. Satellite data collection and location could result in a considerable improvement to the data set. 相似文献
539.
M Casolino V Bidoli E De Grandis M P De Pascale G Furano A Morselli L Narici P Picozza E Reali R Sparvoli A Galper M Korotkov Y Ozerov A Popov G Mazzenga M Ricci G Castellini S Avdeev M Boezio W Bonvicini A Vacchi N Zampa P Spillantini P Carlson C Fuglesang 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,31(1):135-140
In this work we present preliminary results of nuclear composition measurements on board space station MIR obtained with SILEYE-2 particle telescope. SILEYE-2 was placed on MIR in 1997 and has been working since then. It consists of an array of 6 active silicon strip detectors which allow nuclear and energetic identification of cosmic rays in the energy range between approximately 30 and 200 MeV/n. The device is attached to an helmet and connected to an eye mask which shields the cosmonaut eyes from light and allow studies of the Light Flashes (LF) phenomenon. In addition to the study of the causes of LF, the device is used to perform real time long term radiation environment monitoring inside the MIR, performing measurements in solar quiet and active days. 相似文献