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991.
992.
Using power resources of the outer space and its industrialization have become an urgent task in the development of present day civilization. Solar energy is the most suitable basis for power supply for the majority of projects in the near-Earth space. Passing on to the large-scale space-based systems of power supply requires putting into life demonstration experiments in which power transmission by electromagnetic emission is supposed.In the paper the expedience of developing an autonomous power module which provides the possibility of space programs with great power consumption and wireless transmission system running-up is proved. Ukraine can design a solar power satellite of 10–20 kW power on the basis of the research satellite AUOS-SM. Two variants of design solutions for such satellite with solar arrays of great area are presented. Power transmission to the space vehicle-consumer can be conducted by cable as well as in a wireless way. The possibilities of placing microwave and laser energy transmission systems on board the satellite are analysed. It is shown that a power supply system for space vehicles with transmission distance of thousands km can be designed basing on modern lasers.Some experiments making use of great electric power generated by the plant of the satellite under consideration are proposed. The running-up of electric thrusters which are necessary for orientation and distancing is of great interest. Wireless power transmission may be carried on to a small satellite equipped with electric thrusters. 相似文献
993.
994.
S. Pomp W. Eyrich R. Geyer M. Moosburger F. Stinzing 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1996,370(2-3):381-388
A luminosity-monitor system for the JETSET experiment at LEAR is described. Four silicon-strip detectors are used as position sensitive devices to monitor the elastic
p-scattering. The design concept, data-acquisition and results of the detector system are presented. On-line monitoring is used to assure the proper operation of the JETSET experiment. 相似文献
995.
996.
997.
高性能各向异性Sm2Fe17Nx磁粉的制备 总被引:5,自引:0,他引:5
本文研究了高性能各向异性Sm2Fe17Nx磁粉的制备工艺路线与工艺参数。优化了制备与工艺参数。已制备出磁性能达到:Br=1.39T,Hci=850KA/m和(BH)m=236KJ/m^3的各向异性Sm2Fe17N2.88磁粉,该磁粉的各向异性场HA达到20T。 相似文献
998.
This paper compares the profiles of research output and transnational cooperation (as revealed through multicountry publications) of thirty six countries in ten subfields of Physics during the period 1981–1985. The data for comparative analysis were taken fromBraun et al. Since raw counts of publications are confounded by the size of the countries and the size of the research fields, this comparison is made, using relative indicators — activity index and collaboration index. The structures of research output and transnational cooperation are analyzed through Correspondence Analysis, which leads to the identification of countries with similar profiles (of research output and transnational cooperation) and the spatial representation of countries and Physics subfields. The configurations of research output and transnational cooperation are compared to assess the concordance between the policies of these countries for research and transnational cooperation in Physics. 相似文献
999.
A novel carrier and clock synchronisation scheme for tamed frequency modulation is presented. It requires one complex sample per bit, like the digital Costas loop for offset in-phase and quadrature modulations, and is based on processing baseband samples of the phase of the received signal. The performance of the synchroniser is assessed by S-curves and simulated acquisition trajectories 相似文献
1000.
The authors have implemented chirped distributed feedback (DFB) grating lasers with phase shifts [λ/8, 2λ/8 and 3λ/8] distributed continuously over various axial distances, using their recently proposed method for producing bent optical waveguides. The singlemode stability of the lasers with distributed phase shifts was found to be considerably higher than for lasers with abrupt phase shifts 相似文献