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1.
计算机卡管理系统用于机房的管理工作,有一般使用人员和普通管理员和系统管理员三部分。普通用户可以查看自己的上机情况;普通管理员可以登记上机卡,修改上机卡和删除作废卡,挂失机卡,可以进行多种组合查询;而系统管理员有最高权限,可以进行所有操作。  相似文献   

2.
Linda Billings   《Space Policy》2006,22(3):162-164
A space tourism industry appears to be about to take off. Businesses have announced plans to launch people into suborbital space for $200,000/person, with flights beginning as early as 2008. A brief review of the history of the idea of space tourism over the past four decades—and an awareness that many ventures have quietly shelved their grandiose plans—might aid thinking about the prospects for development of a safe and thriving space tourism industry. Today's space tourism model emphases the concept of luxury, and the lifestyle of hyper-consumption. It may be worth considering whether and how this conception of space tourism might affect the future of space exploration.  相似文献   

3.
文章基于航天器无源产品在二次电子倍增微放电过程中,多载波信号通过会在近载波产生互调产物这一机理,介绍了在多载波情况下,用检测近载波互调产物变化来检测微放电的新方法。依据无源互调的幂级数非线性分析方法,建立双载波线性模型加以分析,说明距离载波较近的三阶互调产物的功率变化比载波功率变化快,提供了这种检测方法的理论依据,最后用实验结果验证了此方法。  相似文献   

4.
根据测量不确定度的评定方法,分析和计算低温热敏电阻温度计校准装置的测量不确定度。通过校准结果的不确定度评定,掌握校准装置的计量性能及误差来源,为国防计量标准的建立、实行与考核提供不确定度评定的依据。  相似文献   

5.
热控涂层是保证卫星正常工作、延长卫星在轨工作寿命的重要温控手段。传统的喷涂方式虽能满足质量要求,但存在一定的问题。文章结合卫星常用热控涂层的性能和特殊性要求,首先分析了涂层与基底材料的热学性能、力学性能,进而对各种常用喷涂方式进行适用性试验研究,最终确定无气喷涂是较适用于卫星热控涂层的喷涂方式。  相似文献   

6.
为了防止空间结构与机构产品中的非金属材料对航天器造成污染,要在产品装配前去除其中的可挥发性物质,需对产品进行真空烘烤清洁处理,因此研制了一套结构与机构防污染的真空烘烤设备。该套设备主要包括真空容器、热沉、真空抽气系统、氮系统、去污染系统、电气控制系统等。文章对该设备的系统组成、主要性能指标及使用功能进行了详细的说明。  相似文献   

7.
文章介绍了航天器磁环境试验数据库的建设方案,重点介绍了数据库一些技术特点,如应用元数据驱动的软件架构、构建面向对象的工程数据库模型、引用虚拟XML数据库技术以及接口编程的实现方法。数据库的建设有利于磁试验数据的规范管理和有效利用,为空间磁环境专业的发展提供数据支持。  相似文献   

8.
A. Hansson 《Space Policy》1994,10(4):307-321
Because of the physical scale of human operations at present, we need to extend them into the Solar System for sustainability and into interstellar space for knowledge. Stabilizing the population on Earth, as well as reducing poverty, is vital, as is a more environmentally appropriate demographic transition than the historical one. Space assets can contribute most to strategic threats in areas like power and minerals and can also assist global education. Such public interest is important as education, but it is vital to remember that a certain level of precision in materials and engineering is needed before ideas become realizable. The crucial step is to turn the space environment to an open market and override the present government monopoly constraint. As a start, a Center for International Space Industrialization Research (CSIR) is to be set up as a model for the better understanding of the issues involved, thus making a case for strategic investment for space assets.  相似文献   

9.
《Space Debris》1999,1(4):345-349

Instructions for Authors

Instructions for Authors  相似文献   

10.
SPACECRAFT ENVIRONMENT ENGINEERING publishes both academic and technological papers.Sponsored and published bimonthly by Beijing Institute of Spacecraft Environmental Engineering,this journal covers novel experimental and theoretical results in the field of spacecraft environmental engineering,including subject reviews as well as specialized  相似文献   

11.
《航天器环境工程》是中国科技核心期刊,由北京卫星环境工程研究所主办,是航天器环境工程科技人员的学术园地,国内公开发行。它遵循百花齐放、百家争鸣的方针,广泛报道航天器环境工程专业领域的研究成果、技术成就、学术见解和经验总结,开展学术讨论和专业技术交流,并适当介绍国外本专业的有关信息和发展趋势。读者对象主要是从事航天器环境工程的科学研究人员和工程技术人员、从事航空航天和相关领域的科研人员、以及大专院校的教师和学生等。  相似文献   

12.

Instructions for Authors

Instructions for Authors  相似文献   

13.
The first European space conference was held in Paris from 22 to 24 April 1991. There were disappointingly few continental European delegates, which is perhaps explained by the fact that these people already know what is happening on the European space scene, something a variety of speakers attempted to cover.  相似文献   

14.
The US National Commission on Space has recently issued its report, Pioneering the Space Frontier. As the US Founding Fathers laid down the basic principles which are the foundation of US society, the Commission has articulated certain basic principles which reflect the fundamental values of the American people. These principles lay the basis for the Commission's vision of space exploration and settlement and its benefits for the USA and all of humankind.  相似文献   

15.
16.
《航天器环境工程》是中国科技核心期刊,由北京卫星环境工程研究所主办,是航天器环境工程科技人员的学术园地,国内公开发行。  相似文献   

17.
18.
一种星载计算机操作系统容错引导算法研究   总被引:1,自引:0,他引:1  
将软件冗余备份与SPARC V8构架芯片EDAC相结合,提出了一种新型星载计算机操作系统容错引导算法。该算法首先在EEPROM中备份三份操作系统文件,星载机上电或复位后,利用硬件EDAC功能对引导的操作系统文件进行错误检测及纠错,当检测主操作系统文件错误并且无法纠错时,则屏蔽错误操作系统文件自动引导备份操作系统文件,星载机仍可正常启动。与目前采用的硬件编码容错技术及软件冗余容错算法相比,该算法在有效降低硬件成本和软件消耗的同时,实现了对操作系统文件的检错纠错及错误屏蔽功能,提高了操作系统数据的可靠性。该算法可以为星载机容错设计提供参考。  相似文献   

19.
地球同步轨道(GEO)卫星在轨期间将遭遇空间带电粒子辐射,导致的电离总剂量效应会损伤星上的电子元器件。在对GEO卫星典型结构进行屏蔽设计时,采用钽箔等材料对卫星结构大开口处进行封堵,又用屏蔽厚度的实体相交法求解卫星的屏蔽性能。建立卫星的三维屏蔽厚度模型,对比屏蔽设计前后的总剂量值,同时分析该封堵方法对卫星机热系统的影响。通过对GEO卫星结构三维屏蔽性能的分析,验证了该封堵方法的有效性。  相似文献   

20.
CubeSats and small satellites have potential to provide means to explore space and to perform science in a more affordable way. As the goals for these spacecraft become more ambitious in space exploration, moving from Low Earth Orbit (LEO) to Geostationary Earth Orbit (GEO) or further, the communication systems currently implemented will not be able to support those missions. One of the bottlenecks in small spacecraft communication systems is represented by antennas' size, due to the close relation between antenna gain and dimensions. Current antennas for CubeSats are mostly dipole or patch antennas with limited gain. Deployable (not inflatable) antennas for CubeSats are currently being investigated, but these solutions are affected by the challenge of packaging the whole deployable structure in a small spacecraft.The work that we propose represents the first attempt to develop an inflatable antenna for CubeSats. Inflatable structures and antennas can be packaged efficiently occupying a small amount of space, and they can provide, once deployed, large dish dimension and correspondent gain. Inflatable antennas have been previously tested in space (Inflatable Antenna Experiment, STS-77). However they have never been developed for small spacecraft such as CubeSats, where the packaging efficiency, the deployment, and the inflation represent a challenge.Our study explores for the first time the possibility of developing such antenna in a way compatible with CubeSat dimensions and constraints. The research provides answers on the possible dimensions for an inflatable antenna for small satellites, on the gain and resolution that can be achieved, and on the deployment and inflation mechanism compatible with CubeSat. Future work in the development of the antenna will include the test of the antenna in flight during a specific technical demonstration mission.The article is structured as follows: context and motivation for Cubesat inflatable antenna are described; then a study to design the antenna which achieves the required performance metrics, while respecting the constraints imposed by CubeSat structure, is presented.  相似文献   

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