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511.
John B. Rhinelander 《Space Policy》1986,2(2)
This article reviews the key provisions of the ABM Treaty and the major issues of interpretation which need to be resolved. The various phases of the US Strategic Defense Initiative are discussed, showing that permitted SDI research may cross over the prohibited development and testing beginning in 1988. Cooperative research with US allies is discussed in terms of the Treaty constraints. US and Soviet ballistic missile defence programmes are summarized and the major US and Soviet compliance issues, including the Krasnoyarsk radar, are reviewed. The author argues that limitations on defensive systems remain a precondition to limitations on offensive systems. The ABM Treaty should be enhanced by agreed interpretations, a separate ASAT treaty, and perhaps four amendments to the ABM Treaty. 相似文献
512.
The GPS (Global Positioning System) signal contains information which, when properly combined with information from INS and other sensors, provides exceptionally high accuracy position, velocity, attitude, and time measurements. These ten elements of information (three each in position, velocity, and attitude, and one in time) are common, in various combinations, to most avionics functions. When viewed from a system perspective, this high-precision information can be thought of as an integration basis, or a reference set, which offers opportunities for reconfiguration of the offensive, defensive, communication, navigation, and other sensors. Various integration architectures for fusion of these sensors can inherently enhance, enable, or severely limit these potential mission capabilities. The choice of integration architecture, can directly and profoundly affect performance, cost of integration, cost of ownership, and exploitation of much greater mission capability. This is illustrated by an example 相似文献
513.
The launch of the Israeli satellite Ofeq-1 during September 1988 has significant regional and global implications. These include the proliferation of both surveillance satellites and ballistic missiles, the latter having the potential to deliver conventional, chemical and nuclear warheads to areas situated many hundreds of miles away. This paper addresses both the origins of the Israeli booster technology and the many implications of the satellite launch. It then speculates on their political and arms control consequences. It concludes that in light of the parallelism that has evolved between nuclear and chemical weapons and ballistic missiles, there is an increasing need to develop global and, if appropriate, regional and bilateral strategies to limit missile proliferation and bring the issue to the forefront of international political debate. 相似文献
514.
V.S. Dokukin A.K. Markeev E.V. Mishin Ju.Ja. Ruzhin V.V. Fomichev I.A. Zhulin V.N. Ivchenko G.P. Milinevsky R.I. Moisya R.Z. Sagdeev 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(2):5-15
The rocket experiment ZARNITZA-2 on artificial electron beam injection in the ionosphere was carried out on September 11, 1975. Great attention was paid to the study of phenomena occurring in the near-rocket region. The results of the experiment are discussed in terms of a beam plasma discharge. 相似文献
515.
516.
Bistatic radar cross sections are determined for scattering from a cloud of randomly positioned resonant dipoles (chaff). Dipoles are assumed to be horizontally oriented with axes randomly oriented in the horizontal plane. The cloud is arbitrarily located relative to an illuminating source having an arbitrary (elliptical) polarization. Cloud cross section is found for an arbitrarily located receiver that views the cloud with an antenna of arbitrary polarization. Cross section applicable to the receiver's orthogonal polarization is also found. 相似文献
517.
Roberta L. Klatzky Andrew C. Beall Jack M. Loomis Reginald G. Golledge John W. Philbeck 《Spatial Cognition & Computation》1999,1(4):495-497
Volume Contents
Contents of Volume 1 相似文献518.
519.
Blecki J. Savin S. Rothkaehl H. Stasiewicz K. Wronowski R. Němeček Z. Šafránková J. Kudela K. 《Cosmic Research》2003,41(4):332-339
This paper presents a review of observations of low-frequency plasma waves together with plasma particles performed by Interball 1 and its subsatellite Magion 4 and by the Freja satellite in different cusp regions. The detailed study of the wave spectra together with the electron distribution functions indicates the correlation between the presence of lower-hybrid waves and of particles with energies higher than in the surrounding space. These experimental facts suggest that strong coupling between waves and particles is responsible for plasma heating. The Freja data with a high time resolution allow identification of the process of energy transport via a cascade from low frequency waves to high frequency waves accompanied by electron energization. 相似文献
520.
The effect of a 20-day space flight on water, Na+, K+, Mg2+, Ca2+ and glycogen contents as well as on activities of glycogen metabolism enzymes--glycogen synthetase and glycogen phosphorylase--of rat skeletal muscles was studied. This data is regarded as an integral test characterizing the state of contractile tissue of the animals at the final stage of flight aboard biosatellites. The measurements indicate that there were no significant changes of cations and glycogen contents nor of the enzymic activities in fast-twitch muscles during the 20-day spaceflight. At the same time dehydration in these muscles was observed, which disappeared on the 25th postflight day. In slow-twitch antigravitational skeletal muscle (m. soleus) there was a decrease of K+ and increase of Na+ in the tissue contents. The changes disappeared at the end of the on-earth readaptation period. From the pattern of these observations, we can conclude that the 20-day space flight leads to some reversible biochemical changes of the rat skeletal muscles. A conclusion can be drawn about necessity of creating, aboard the spaceship, an artificial load on antigravitational skeletal muscles. 相似文献