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For decades, Western European nations have been comparatively uninterested in the military use of space, largely content to rely on the far greater resources of the USA in this area. Today, however, the traditional belief that the security requirements of ‘the West’ are synonymous with those of the USA is increasingly open to challenge. A new European defence identity is emerging, keen to achieve greater autonomy in the security field, albeit remaining within the overarching framework of NATO. Consequently there is a growing requirement for indigenous European capabilities in terms of military space assets. This requirement has been met in part by the establishment, by the Western Union, of a satellite centre in Spain, which currently analyses commercially procured satellite imagery. The centre's capabilities may be expanded if the WEU states decide to add a space-based element — either their own satellite system, or participation in an existing multinational programme. Such a decision is due to be taken towards the end of 1995. This paper concludes by briefly examining the political and security implications of such a decision.  相似文献   
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Shock waves, as evidenced by type II radio bursts, often accompany flares and coronal mass ejection transients. At present, the density enhancements observed by coronagraphs are believed by some to be ejected matter from the low corona, and by others to be the compressed material behind a shock front. If the former is correct, one would expect in some cases to see a density enhancement, associated with the compression region of the shock, some distance ahead of the transient ejecta. Such a density enhancement has not been previously reported.The coronal transient of 1980 June 29 (0233 UT) was observed with the High Altitude Observatory's Coronagraph/Polarimeter aboard SMM. This flare-associated coronal transient event was well observed with the Culgoora Radioheliograph, including a well-developed type II burst. Visible on the coronagraph images is a faint circular arc moving out well ahead of the transient loops. This arc is moving at more than 900 km s?1 while the transient itself is moving at a speed of about 600 km s?1. Both the arc and transient appear to have originated either prior to the X-ray flare or at some height above the flare at the time of the flare. The type II burst observed at Culgoora is associated with the transient loops, and no type II emission is identified with the faint arc.Due to its great speed, we interpret the faint arc as a manifestation of a shock wave, but also envision a separate shock wave associated with the transient loops as evidenced by the type II emission. Preliminary density measurements are consistent with this interpretation, and show the outer shock wave associated with the faint arc to have a Mach number MA ≤ 1.7. At present we have no convincing explanation for the lack of a type II burst in association with the arc.This work was supported in part by NASA through grants NSG-7287 and NAGW-91 to the University of Colorado, Boulder, and S-55989 to the High Altitude Observatory, National Center for Atmospheric Research. The National Center for Atmospheric Research, NCAR, is sponsored by the National Science Foundation.  相似文献   
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The military satellite systems currently operated by the UK and France will both reach the end of their projected life around the turn of the century, so there is a real possibility of collaboration to develop a successor system. Collaboration can have its own disadvantages, but the military, political and economic advantages could be substantial. The oppurtunity to explore these potential gains must not be lost.  相似文献   
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Alasdair McLean   《Space Policy》1999,15(4):9044-198
The UK has made use of dedicated, national military satellites for communications since November 1969. The replacement of the current system, Skynet 4, which will reach the end of its design lifetime early in the next century, is currently under consideration. Possible options which have been mooted to date include a new generation of a national satellite system (Skynet 5), or one of several international collaborative projects. However, these appear to have been superseded by a new possibility — a privately, commercially funded national system under the government's Private Finance Initiative (PFI). This paper examines the historical reliance of the UK on military satellite communications, the options for the next generation of such systems, and, drawing on the UK example, raises a number of questions concerning the potential significance of reliance on commercial enterprise to provide a key element of defence capability.  相似文献   
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A. McLean  A. Swankie 《Space Policy》1998,14(2):107-114
Helios is the only example of a multilateral collaborative military space effort currently being pursued within Europe. As such, a unique tripartite project, the first generation of the programme has had significant successes, even though the project has been faced with severe spending constraints and hindered by political obstacles. Helios 2, on the other hand, is not faring quite as well. Plagued by problems, the project has been in effect grounded indefinitely by German reluctance and inability to finance their share of the proposed three satellites. This paper assesses the origins and development of the Helios programme, and the difficulties facing the second generation of this satellite system.  相似文献   
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Space education is a discipline that has evolved at an unprecedented rate over the past 25 years. Although program proceedings, research literature, and historical documentation have captured fragmented pieces of information about student space experiments, the field lacks a valid comprehensive study that measures the educational impact of sounding rockets, Skylab, Ariane, AMSAT, and Space Shuttle. The lack of this information is a problem for space educators worldwide which led to a national study with classroom teachers. Student flown experiments continue to offer a unique experiential approach to teach students thinking and reasoning skills that are imperative in the current international competitive environment in which they live and will work. Understanding the history as well as the current status and educational spin-offs of these experimental programs strengthens the teaching capacity of educators throughout the world to develop problem solving skills and various higher mental processes in the schools. These skills and processes enable students to use their knowledge more effectively and efficiently long after they leave the classroom. This paper focuses on student space experiments as a means of motivating students to meet this educational goal successfully.  相似文献   
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A new era? Military space policy enters the mainstream   总被引:1,自引:0,他引:1  
Alasdair McLean   《Space Policy》2000,16(4):243-247
A military dimension to the use of space has existed since the earliest days of space activity. Historically, military space policy has been somewhat peripheral, but the ever increasing use of space in support of military objectives has now driven it into the mainstream of military planning. This has resulted in new consideration being given, particularly in the USA, to the organisation of space for national security and also raised the question as to whether national security interests demand space superiority and dominance.  相似文献   
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