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881.
In all developed countries, once it emerged from the amateur era, Space (and especially rocketry) moved on the public agenda because of its potential significance for both the civil and military policies of governments (coupled with its appetite for new money). In the UK the policy treatment of Space broadly paralleled that in other countries until the post-Empire trauma, the burn-out of the White-Hot Technological revolution of Harold Wilson, and the financial crises of the 1970s exhausted the public appetite for large scale publicly funded projects in high technology. The culmination for Space of these pressures came in 1986–1987 when the UK rejected the emerging international consensus and, almost alone, stayed outside the manned space commitments which developed into the International Space Station. In this paper, Colin Hicks will review the UK political developments which led up to the 1986–1987 decision and how the politics and organisation of UK space activity have developed since then to the point where in 2008 a major government review of the UK involvement in manned space was commissioned. 相似文献
882.
NASA和ESA的空间系统维修性/维修技术研究 总被引:4,自引:1,他引:3
本文对维修性/维修工程技术在NASA和ESA的发展做了简要回顾,并从人的因素对空间系统的影响、承制方负责全寿命周期保障、改进的RCM方法、RMA信息的标准化、仿真技术、在轨维修等几个方面对NASA和ESA在维修性/维修工程领域的理论、技术,以及NASA和ESA在这些方面实施维修性/维修工程的情况作了介绍和分析,其中对改进的RCM方法作了详细的介绍。 相似文献
883.
Satellite positioning technology has been widely used in all kinds of military and civil land, marine, space and aeronautical target positioning tasks, naviga tion activities and accurate surveying measurements since 90 s in the last cen tury due to its advantage in providing all-weather, real-time, three dimensional and high precision positioning information, as well as speed and accurate timing information. By now, it has already formed a new hi-tech industry basically.This paper briefly reviews the development of the global satellite positioning and navigation technologies including the basic information of China's "Plough navigation system", introduces the history of satellite positioning technology and its major application fields as well as the status quo of this being industri alized trade in China, gives an account of the writers' vision for the application and prospect of the satellite positioning technologies in China, and approaches the tactics and stresses of the satellite positioning technology's application and its industrialization future in China. 相似文献
884.
GAN Weiqun 《空间科学学报》2006,26(Z1)
For the past two years, some real progress has been made in Chinese Space Astronomy, though we have not launched any missions exclusively belonging to the scope of Astronomy. In order to program the next five years' national plan (2006-2010), the Chinese Space Agency organized a series of authorized evaluations for the future missions. Among more than ten astronomical mission proposals, several were selected to give the green light to continue for their Phase A studies. We try to briefly outline these proposals. 相似文献
885.
Introduction to Meridian Space Weather Monitoring Project 总被引:1,自引:0,他引:1
The Meridian Project is a ground- based network program to monitor solar-terrestrial space environment, which consists of a chain of ground-based observatories with multiple instruments including magnetometers, ionosondes, HF and VHF radar, Lidar, IPS monitors, sounding rockets etc. The chain is mainly located in the neighborhood of 120°E meridian, and is thus named the Meridian Project. It has officially been approved by the Chinese government and will be finished by 2009. This talk will give an overview of the Meridian Project and the proposed International Space Weather Meridian Circle Program. 相似文献
886.
887.
我国大型空间环境模拟器的铝热沉,工作于-196~+100℃的温度,内压最高1.6MPa。其中主容器热沉是一个直径10.5m、高20m 的鼠笼形立式铝列管热交换器。整个热沉由2500多根铝管焊接而成,焊缝数量超过5000道。热沉有很严格的真空气密性要求,整个热沉的总漏率要求不大于1×10~(-6)Pa·m~3/s。文章分别从管件检测、纯铝焊接、高真空检漏等方面论述了确保热沉高真空气密性的措施。 相似文献
888.
Frank Verheest 《Space Science Reviews》1994,68(1-4):109-114
Nonlinear modes are investigated in magnetized dusty plasmas, where the dust dynamics is modelled by a number of cold, highly negatively charged and very massive fluids, besides ordinary electrons and protons. Several low-frequency motions occur which are typical for the dust components, some of them described by model equations such as the derivative nonlinear Schrödinger equation for electromagnetic waves. One can include equilibrium drifts and even fluctuations in the grain charges. Most of the preceding conclusions are relevant for different kinds of astrophysical and heliospheric plasmas. 相似文献
889.
基于NiosII的SoPC系统在时统系统中的应用开发 总被引:1,自引:0,他引:1
N iosII处理器是一种用户可随时配置和构建的32位指令集和数据通道的嵌入式系统微处理器IP核,与传统的8/16位系统相比,无论处理器的结构还是开发手段上都发生了较大变化。本文主要介绍了N iosII的性能特点和基于N iosII的SoPC系统的功能构架,给出了基于N iosII处理器的SoPC系统在时统系统中的一种应用方案。其中重点介绍了该方案的SoPC系统设计实现和软件设计实现。 相似文献
890.
相机热门是大口径高分辨率空间相机的关键部件。文章概要介绍了空间相机热门机构的组成、工作原理及设计要点。 相似文献