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81.
Wulf von Kries 《Space Policy》2000,16(3):75
This Viewpoint argues that the 1986 UN Principles on Remote Sensing have failed to anticipate the growth and broadening of the Earth observation field and are now less relevant. It traces the development of remote sensing: from a narrow government-controlled base, three distinct sectors of military, civil (i.e. public) and commercial Earth observation can now be distinguished and the latter is making images ever more widely and easily available. There has been no international effort to adjust the international legal regime to this changing environment and even the USA's remote sensing policy has basically been reactive. It is impossible now to conceive an overarching remote sensing policy and the challenge will be to shape each sectoral regime appropriately. 相似文献
82.
83.
Stephan F. von Welck 《Space Policy》1986,2(3)
The two superpowers engaged in power politics on Earth, the USA and the USSR, have devoted great financial and technical efforts to the exploration, control and use of outer space, primarily to gain power-political advantages. This article considers the issue of power politics in outer space. The history and the instruments of ‘cosmopolitical power’ are discussed, as well as the attempts to limit the superpowers' dominance. A united Western Europe is seen to have a major role to play in providing a counterbalance to the concentration of space power. 相似文献
84.
M.E. Wiedenbeck N.E. Yanasak A.C. Cummings A.J. Davis J.S. George R.A. Leske R.A. Mewaldt E.C. Stone P.L. Hink M.H. Israel M. Lijowski E.R. Christian T.T. von Rosenvinge 《Space Science Reviews》2001,99(1-4):15-26
Cosmic-ray isotope observations from NASAs Advanced Composition Explorer (ACE) mission have been used to investigate the composition of cosmic-ray source material. Source abundances relative to 56Fe are reported for eleven isotopes of Ca, Fe, Co, and Ni, including the very rare isotopes 48Ca and 64Ni. Although the source abundances range over a factor 104, most of the ratios to 56Fe are consistent with solar-system values to within 20%. However, there are some notable differences, the most significant being an excess of (70±30)% relative to the solar system for the cosmic-ray source ratio 58Fe/56Fe. The possible association of such an excess with a contribution to the cosmic-ray source from Wolf–Rayet star ejecta is discussed. 相似文献
85.
This Note emphasizes the need, in a space station, of an emergency room, especially equipped with regard to clean air and competent paramedical personnel. The establishment of some degree of artificial gravity is desirable. 相似文献
86.
R von Baumgarten J Kass H Vogel J Wetzig 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1989,9(11):223-230
Conscious space orientation depends on afferent information from different sense organs including the labyrinth, the eyes, tactile cues from the skin, joint receptors, muscle spindles, tendon organs and possibly viscera. An important role is played by impulses from the cervical position receptors in interaction with concomitant information from the otolith system. In order to isolate the effect of cervical position receptors from that of the otolith system, space experiments in orbital weightlessness and in parabolic aircraft flight were performed. It was found that stimulation of the neck receptors in weightlessness markedly influences the perception of the subjective vertical and horizontal and in addition has a weak effect on ocular torsion. 相似文献
87.
P. Koepke K.T. Kriebel B. Dietrich 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1985,5(6):351-354
Errors in the determination of the shortwave radiation budget from broadband satellite measurements at the top and at the bottom of a cloudless atmosphere due to uncertainties of the actual parameters of the atmosphere and the surface are derived by computer modelling. The model uses measured bidirectional reflectance functions and realistic values of the optical parameters of the atmosphere. Examples are presented which show the range of such uncertainties. Neglecting the anisotropy of the reflection function of land surfaces results in high uncertainties of the shortwave radiation budget, both at the top and the bottom of the atmosphere. The uncertainties caused by actual uncertain atmospheric parameters are low if data of the meteorological network are properly used. 相似文献
88.
The growth of low- and medium-Earth orbit mobile satellite communications poses a threat to radio astronomers which could be mitigated by the establishment of international radio quiet zones (IRQZs), where communications traffic is managed (not eliminated) to allow radio astronomy to continue. Using the prototype of national such zones in the USA, this article explains how the system would work and discusses the international legal parameters that would bound it, drawing on current aerospace, outer space and high seas legislation. Precedents for an IRQZ—Exclusive Economic Zones, denuclearised zones and the Antarctic regime—are also examined. 相似文献
89.
Europe has at last started to integrate the assets of its broad set of actors into a comprehensive European Space Strategy. But will this first approach be ambitious enough to strengthen Europe as a global actor? In this contribution, the individuals responsible for strategy in the French and German space agencies seek an answer to this question. They do so by reviewing the historical background to European space efforts, and its role in shaping present-day activities; setting forth a vision of how Europe should proceed in space, and measuring current progress in drafting a European space strategy against this vision. 相似文献
90.
Manzey D 《Acta Astronautica》2004,55(3-9):781-790
Human exploratory missions to Mars represent the most exciting future vision of human space flight. With respect to the distance to travel and mission duration, these missions will provide unique psychological challenges that do not compare to any other endeavor humans ever have attempted. The present paper presents outcomes of two recent projects sponsored by the European Space Agency--Humex and Reglisse--where these challenges and risks have been analyzed in some detail, and where concepts for future research have been developed. This presentation involves three steps. At first, it will be shown that our current psychological knowledge derived from orbital spaceflight and analogue environments is not sufficient to assess the specific risks of mission into outer space. Secondly, new psychological challenges of missions to Mars will be identified with respect to three different areas: (1) individual adaptation and performance, (2) crew interactions, and (3) concept and methods of psychological countermeasures. Finally, different options and issues of preparatory psychological research will be discussed. 相似文献