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861.
862.
The organization principles of constructing the European system of warning about dangerous situations in the outer space are
considered in the paper. 相似文献
863.
Design of a three-axial accelerometer-seismometer, constructed on the basis of two-coordinate sensors (sensitive elements)
of high and low accelerations, is considered in the paper. This instrument is applied for gravi-inertial measurements. Basic
characteristics of the instrument are described, as well as the technique and results of its standardization. 相似文献
864.
A problem of cruciform parachute deployment is considered. The process of deployment is simulated using the present-day numerical methods in the continuum mechanics, that is, the method of concentrated masses and the method of vortex frames. The calculation results are compared with the experimental data. 相似文献
865.
An analysis of the existing astrometric and radar observations of the Apophis asteroid is performed. On the basis of this
analysis, characteristics of future measurements of the asteroid orbit and limitation on their conduction are accepted. A
proposed launching of a spacecraft to the asteroid in order to obtain high-accuracy measurements of its distance and radial
velocity is also considered. Trajectories of the flight to the asteroid in 2012–2022 are studied. Estimates of the accuracy
of the Apophis position determination at various sets of both available and planned measurements at various numbers of determined
parameters are obtained. The method of estimating accuracy is similar to that used in [1] for the Vega project. 相似文献
866.
867.
868.
The technical parameters of a holographic setup and an optical scheme for registration of holograms are described. The holographic interferograms of vibration modes for the GTE turbine and compressor blades vibrating at resonance frequencies are presented. 相似文献
869.
K. Abe H. Fuke S. Haino T. Hams M. Hasegawa A. Horikoshi A. Itazaki K.C. Kim T. Kumazawa A. Kusumoto M.H. Lee Y. Makida S. Matsuda Y. Matsukawa K. Matsumoto J.W. Mitchell A.A. Moiseev J. Nishimura M. Nozaki R. Orito J.F. Ormes N. Picot-Clémente K. Sakai M. Sasaki E.S. Seo Y. Shikaze R. Shinoda R.E. Streitmatter J. Suzuki Y. Takasugi K. Takeuchi K. Tanaka N. Thakur T. Yamagami A. Yamamoto T. Yoshida K. Yoshimura 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
The Balloon-borne Experiment with a Superconducting Spectrometer (BESS) is configured with a solenoidal superconducting magnet and a suite of precision particle detectors, including time-of-flight hodoscopes based on plastic scintillators, a silica-aerogel Cherenkov detector, and a high resolution tracking system with a central jet-type drift chamber. The charges of incident particles are determined from energy losses in the scintillators. Their magnetic rigidities (momentum/charge) are measured by reconstructing each particle trajectory in the magnetic field, and their velocities are obtained by using the time-of-flight system. Together, these measurements can accurately identify helium isotopes among the incoming cosmic-ray helium nuclei up to energies in the GeV per nucleon region. The BESS-Polar I instrument flew for 8.5 days over Antarctica from December 13th to December 21st, 2004. Its long-duration flight and large geometric acceptance allow the time variations of isotopic fluxes to be studied for the first time. The time variations of helium isotope fluxes are presented here for rigidities from 1.2 to 2.5 GV and results are compared to previously reported proton data and neutron monitor data. 相似文献
870.
N.F. Allard 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
In order to calculate the opacity of a gas it is necessary to consider how its constituent atoms are perturbed by the surrounding medium. This is required both in order to calculate the equation of state, and in order to determine the profiles of the spectrum lines. In this work we report new theoretical Li line profiles perturbed by H2 and their dependence with temperature. 相似文献