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1.
Poland has a long-standing tradition in space activities. Polish institutions have participated as co-investigators in almost all European Space Agency (ESA) science projects, as well as on many other missions. However, the first Polish satellite (PW-SAT) was only launched in 2012. Poland was one of the first Eastern European countries to conclude a Cooperation Agreement with ESA in the peaceful use of outer space; it was signed in 1994 and followed by a second in January 2002. Negotiations on Polish membership in the ESA were started in autumn of 2011, and ended in April 2012. Following ratification of the agreement, Poland officially became the 20th Member State of ESA on 19 November 2012. This article examines how Poland is setting its way as a space nation. It describes recent developments in the Polish space programme, including the road to Poland's full membership in the European Space Agency.  相似文献   

2.
李莉 《中国航天》2001,(5):38-41
战斧,是一个耳熟能详的名字,90年代以来的几场局部战争使其名声大振。自1991年以来,美国海军平均每年要消耗100枚战斧导弹。从海湾战争到科索沃,近千枚战斧从一艘艘美国战舰和潜艇上发射,使得战斧成为美国强权政治的急先锋,也成为对别国实施远距离精确打击的中坚力量。 但近几场局部战争同时也提出了要发展一种造价便宜、全天候作战、精确打击以及可对加固目标进行打击的新型战斧的要求。在这种背景下,战术战斧(TacTom)应运而生。北约空袭南联盟后,美国海军根据战斧巡航导弹的作战使用,开始重新评估未来战斧巡航…  相似文献   

3.
2005年12月22日,我国在北京-西安-成都-昆明以东的广大空中交通管制区实施了雷达管制,这使得空中交通管制工作进入了新的时代,贵阳区域管制室也开始了划时代的雷达管制工作。实施之后,随着雷达管制工作的深入运行,一些在实施前未考虑到的问题相继暴露出来。在经过前期强化雷达管制模拟机培训后大部分管制员在实际运行过程中仍感到有不理解的问题,涉及到标准通话用语、雷达管制间隔、雷达管制和程序管制之间的间隔、雷达盲区、目视飞行与仪表飞行之间等。尤其是对间隔的掌握和通话术语的理解上存在着偏差,部分管制员在机组不作位置报时缺乏主动管制的意识,感觉到指令发的不流畅。为什么在作了大量的前期雷达管制理论准备工作和雷达管制模拟机培训后,在实际运行中还会有这样的问题,这是因为:一、雷达基本理论不是万能的。不可能解释所有问题、解决运行中的所有矛盾。  相似文献   

4.
随着我国国民经济的迅速发展和改革开放的不断深入,航空领域呈现出前所未有的发展形势,民用航空运输以每年平均10%的速度增长,通用航空的需求与日俱增,军事飞行频繁,对空域资源需求越来越大,空域管理面临的新问题日益突出。本文就我国空域资源相关问题,即如何最大限度地发挥空域资源优势,为不同空域用户提供可靠的空中交通管制服务等问题进行探讨。  相似文献   

5.
The present research examined the effects of disorientation on human ability to locate objects in space in a virtual environment (VE). Participants were asked to memorize the location of virtual objects, and then they were asked to indicate where the objects were located while they were inside a virtual chamber. This procedure was repeated in both eyesclosed and disoriented conditions. Subject pointing responses were used to measure memory for the relative location of objects in virtual space. This method was extended from previous research in a real-world setting. The results showed systematic individual differences in the effects of disorientation on the ability to locate objects in space. Further, the use of strategies played a role in object localization ability, but strategy use was affected by the individual differences in spatial representations used by subjects.  相似文献   

6.
拥有“神舟”、“神箭”等著名宇航品牌,曾经创造了无数辉煌业绩的航天科技集团公司.在第五届珠海航展上又给观众带来了惊喜:除了新一代运载火箭等许多在研产品模型闪亮登场外.神舟5号飞船返回舱精彩亮相,嫦娥1号卫星、环境1号C卫星等产品模型也一同展出。这些科技含量极高的产品虽然用途不同.但细心的观众不难从中看出“可持续发展”的影子,注重环境、保护生态、高效节能已成为航天科技发展的新主题。  相似文献   

7.
Basing his comments around a report on the Space Power Systems 1997 conference, ‘Energy and Space for Humanity’, held in Montreal, 24-28 August 1997, Richard Boudreault describes the progress made in getting the concept of power from space accepted by the terrestrial utilities. Increasing worries about the sustainability of current power sources together with deregulation of power distribution make space power more attractive. However, the high cost of access to space is a barrier, though this is starting to fall.  相似文献   

8.
本文市场经济、社会消极现象、应试教育、高等教育及德育教育自身缺陷等方面对高校德育工作的消极影响加以分析,立足现实,提出问题,与高等教育工作者,德育工作者共同探讨,以求改进完善高校德育工作。作者坚信,真正找到了问题所在,也就找到了解决问题的切入点。  相似文献   

9.
周威 《中国航天》2007,(1):22-24
世界各大宇航公司在激烈的竞争中度过了2006年。新年伊始,让我们回过头来看看这些公司在2006年卫星发射市场上的竞争情况。  相似文献   

10.
The Ariane transfer vehicle (ATV), an Ariane 5 borne, unmanned propulsion vehicle, is designed to transport the logistics needed to resupply the International Space Station (ISS) and the man tended free flyer (MTFF) step 2 with pressurized and unpressurized cargo and to dispose the waste. The ATV is an expendable vehicle and is disposed of by a safe atmospheric burn up. In accordance with the AR5 schedule it should be operational in 1996 for missions toward ISS and beyond the year 2000 for MTFF 2 missions. The main constituents of the proposed ATV are the modified AR5 third stage L5, an upgraded VEB steering the launcher as well as the ATV and the P/L-adaptor providing mechanical and umbilical links to the payload. The mechanical part of the RVD-kit will be placed on the payload-module, the main RVD sensors are located on the adaptor and the needed computer intelligence will be integrated on the VEB. To minimize the development, and recurring costs, the ATV concept fully complies to the idea of maximum use of existing hardware and software, mainly from the AR5, Hermes and Columbus programs thus minimizing development and recurring costs. The ATV is compatible to ISS, MTFF and OMV and is able to transport logistic modules compatible with NSTS and U.S.-expendable launchers.  相似文献   

11.
Cells of the bacterium Pseudomonas aeruginosa, which were genetically modified to produce green fluorescent protein, were entrapped in fluid inclusions in laboratory-grown halite. The bacteria were used to inoculate NaCl-saturated aqueous solutions, which were allowed to evaporate and precipitate halite. The number, size, and distribution of fluid inclusions were highly variable, but did not appear to be affected by the presence of the bacteria. Many of the inclusions in crystals from inoculated solutions contained cells in populations ranging from two to 20. Microbial attachment to crystal surfaces was neither evident nor necessary for entrapment. Cells occurred exclusively within fluid inclusions and were not present in the crystal matrix. In both the inclusions and the hypersaline solution, the cells fluoresced and twitched, which indicates that the bacteria might have remained viable after entrapment. The fluorescence continued up to 13 months after entrapment, which indicates that little degradation of the bacteria occurred over that time interval. The entrapment, fluorescence, and preservation of cells were independent of the volume of hypersaline solution used or whether the solutions were completely evaporated prior to crystal extraction. The results of this study have a wide range of implications for the long-term survival of microorganisms in fluid inclusions and their detection through petrography. The results also demonstrate the preservation potential for microbes in hypersaline fluid inclusions, which could allow cells to survive harsh conditions of space, the deep geologic past, or burial in sedimentary basins.  相似文献   

12.
This article is a literary review focused on the problem of the stress-effect of microgravity. Based on the all-round analysis of data from manned missions and space experiments with rats it is concluded that microgravity as a permanent factor of space flight does not produce an intense chronic stress in either humans or animals. On the other hand, microgravity is responsible for deconditioning of a number of vital systems and of the organism as a whole. On return to Earth, the deconditioned bodies of humans and animals exaggerate the usual terrestrial loads due to gravity forces and respond by acute gravitational stress.  相似文献   

13.
The ability to voluntarily stabilize the head in space during lateral rhythmic oscillations of the trunk has been investigated during parabolic flights. Five healthy young subjects, who gave informed consent, were examined. The movements were performed with eyes open or eyes closed, either during phases of microgravity or phases of normal gravity. The main result to emerge from this study is that the head may be stabilized in space about the roll axis under microgravity conditions with, as well as without vision, despite the reduction of the vestibular afferent and the muscle proprioceptive inputs. Moreover, the absence of head stabilization about the yaw axis confirms that the degrees of freedom of the neck can be independently controlled, as it was previously shown [1]. These results seem to indicate that voluntary head stabilization does not depend crucially upon static vestibular afferents. Head stabilization in space may be in fact organized on the basis of either dynamic vestibular afferents or a postural body scheme.  相似文献   

14.
《中国航天》2010,(11):15-17
<正>6月28日,白宫不那么张扬地推出了其自己的新版《国家航天政策》。就像布什政府、克林顿政府及更早先的各届政府多年来所做的一样,这份14页(加上封面等为18页)的文件在各种民用、商业和国家安全政  相似文献   

15.
航空航天复合材料非热压罐成型研究进展   总被引:8,自引:1,他引:7  
介绍了复合材料非热压罐成型的研究进展,包括非热罐成型用的树脂体系、预浸料技术、纤维自动铺放技术以及双真空袋成型工艺等,探讨了非热压罐技术的发展现状和前景。  相似文献   

16.
近代以来,湖南人才辈出,形成了以曾国藩、谭嗣同、黄兴、毛泽东等为代表的前后相承的人才群体。文章从湖湘文化的影响、湖南人独特的个性特征、便利的地理条件、近代中国社会历史条件和阶级斗争状况等方面阐述湖南人才辈出的形成。  相似文献   

17.
在代表人类最高科技水平的载人航天领域,不仅有许多默默无闻的地面女科学家和女工程师,也有许多丰采夺目的女航天员。她们飞翔在茫茫的太空中,与男航天员比翼齐飞,在人类征服太空的道路上写下了自己辉煌的篇章,创造了航天史上许多个第一的纪录。  相似文献   

18.
Sleep in space     
Manned space flights have shown it is possible to sleep in microgravity. However, some sleep disturbances have been reported which influence performance of the crew and safety of space flight. This paper reviews the main studies of in-flight sleep in animal and man. Most disturbances are related to phase lags due to operational requirements. Factors which can disturb in-flight sleep are analysed: environmental factors. Some of them are secondary to space flight ergonomics. Conversely, effects of microgravity on light-dark alternance are less known and lead to interesting problems of fundamental research, psychological factors, especially during long duration flights.  相似文献   

19.
Czechs in space     
This is a nutshell history of the Czech nation's long-standing interest, and achievements, in space science, technology and education. It attempts to show that despite difficult periods, this country has always been able to bring up new ideas and contribute to progress of sciences. The current transition into market economy, democratic society, and preparation for integration into the European Union is one of those difficult periods. However, given the determination of its people, and proven past record, it has all the prerequisites again to contribute significantly to future space exploration on a global scale, and return to the forefront of technology and science.  相似文献   

20.
沈羡云 《航天员》2009,(6):71-73
在国际空间站上生活,会不会和在地面上生活一样需要打扫卫生呢?如果需要,那么长期考察组的乘员们是怎样打扫卫生的呢?  相似文献   

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