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471.
N. Jasentuliyana 《Space Policy》1994,10(1)
There is a concern in the developing world that industrialized countries have not done all they might under Article 1 of the Outer Space Treaty to make the benefits of space technology available to all countries; some are now seeking codification of rights and responsibilities in this sphere. This article discusses recent debate on the issues by COPUOS and its Legal Subcommittee on whether an additional legal framework is necessary to ensure a fairer distribution of benefits. G77 countries were strongly in favour of some form of technology and information transfer, while industrialized countries favoured the existing practice of developing international cooperative space projects. The author believes that a new set of principles will be formulated in the next few years and that organizations like Intelsat and Inmarsat can provide valuable models for ensuring access through cooperative programmes. 相似文献
472.
473.
The thermal resistance due to conductive heat transfer between two heat generating boxes mounted symmetrically on a thin mounting plate, one side of which is subjected to a constant heat flux and the opposite side is convectively cooled, is considered. The other two sides are maintained at constant temperature. A numerical solution for the temperature field is obtained and the heat transfer between the boxes is found by integrating between the critical heat flow lines. Various nondimensional parameters are identified and their influence on the thermal resistance is studied. 相似文献
474.
Rhoda Shaller Hornstein Gerald L. Shinkle Jerry D. Weiler John K. Willoughby 《Acta Astronautica》1991,25(12):793-798
The widely distributed nature of the Space Station Freedom program, plus continuous multi-year operations will force program planners to develop innovative planning concepts. The traditional centralized planning operation will not be adequate. It will be replaced by multiple small planning centers working within guidelines issued by a central planning authority. Plans will not be optimized; rather, operating efficiency and user flexibility will be blended to satisfy program goals. The key to this new approach is the application of new planning methodologies and system development technologies to accommodate distributed resources that must be integrated. Resources will be distributed to the multiple planning entities in such a way that, when the several plans are built and then integrated, they will fit together with minimal modification. The plan itself will be an envelope schedule containing resource limits and constraint boundaries within which users will be free to make choices of the specific activities they will execute, up to the time of execution. Some level of margin within program guidelines will be built in to allow for variation and unforeseen change. This paper presents the authors' recommended planning approach and cites two NASA systems being developed that will utilize these resource distribution/integration planning concepts, methodologies and development technologies. 相似文献
475.
Tanja L. Masson-Zwaan 《Space Policy》1991,7(4):327-328
An international colloquium on the Spaceplane and the Law was organized by the French Society for Air and and Space Law, with the help of the European Space Agency, the French Civil Aviation Authority, the Centre National d'Etudes Spatiales (CNES) and Air France, and had ICAO, Eurocontrol and the French Ministries of Foreign Affairs, Transport, PTT and Research as its patrons. The purpose of the colloquium was to create awareness of the legal problems that may arise when spaceplanes become reality, and to propose solutions to those problems. The colloquium was held in Paris on 14–15 May 1991. 相似文献
476.
It has been suggested that a daily intake of fluid and salt supplements may be used to prevent bone demineralization in human subjects after prolonged exposure to hypokinesia (diminished muscular activity). Thus, the objective of this investigation was to evaluate the effect of fluid and salt supplementation in the prevention of development of osteoporosis in 64 Wistar rats with an initial body weight of 339-345 g, after exposure to 90 days of hypokinesia. They divided into 4 equal groups: the first group of rats placed under ordinary vivarium conditions and served as vivarium control; the second group were also placed under ordinary vivarium conditions but received daily fluid and salt supplements; the third group were subjected to pure hypokinesia, i.e. without the use of any preventive measures; and the fourth group were submitted to hypokinesia and received daily fluid and salt supplements. For the simulation of the hypokinetic effect the experimental group of rats were kept in small, individual, wooden cages. Through the experimental period the second and fourth group of rats received 8 ml/100 g body wt water and 5 ml 100 g body wt NaCl daily. By the end of the experimental period the animals were decapitated and the spongy matter of tibia and vertebrae of the rats were examined for changes referable to osteoporosis. It was found that the daily intake of fluid and salt supplements caused an increase in the volume density of primary spongiosa of bones. It was concluded that a daily intake of fluid and salt supplements may be used to prevent the development of osteoporosis in rats subjected to prolonged motor activity restriction. 相似文献
477.
R. Wickramatunga 《Space Policy》1991,7(1)
Parties to the Registration Convention are committed to providing the United Nations with certain information about objects they launch into space. This report describes the categories of information required, outlines the inadequacies of the present Register and suggests modifications. 相似文献
478.
Phillip S. Clark 《Space Policy》1991,7(3)
In the last two years the USSR has not only acknowledged publicly for the first time that it was trying to ‘race’ the USA to put the first man on the Moon, but they have finally given some details of the programme, the equipment and the political in-fighting which ensured that the programme was a failure. This article traces the history of the Soviet manned lunar programme and also discusses the implications for the future development of the Soviet manned programme of the giant N-1 booster's cancellation in 1974. 相似文献
479.
480.
对苏联复合材料结构无损检测方法、仪器设备、技术特长和发展方向做了简要述评,并对其采用的典型仪器设备系统技术参数给以简要介绍。最后联系我国固体火箭发动机无损检测工作实际提出了两点建议。 相似文献