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101.
The Institute of Biomedical Problems (IBMP) is the lead institution of the Russian Federation in the area of space biology and medicine. It has successfully implemented a set of innovation-based activities and projects to develop and introduce promising space products and technologies into the practices of Earth health care.  相似文献   
102.
英国Frost & Sallivan咨询公司日前公布了其对未来十年全球军用无人机市场的预测报告,该报告的制定者们认为,在今后十年中,欧洲有可能成为继美国和亚太地区之后的全球第三大无人机销售市场,今后军用无人机市场将成为各飞机制造商争夺的又一重要领域,在2005年巴黎航展上,美国的波音,洛克希德&;#183;马丁和诺斯罗普&;#183;格鲁曼,以色列的JAJ以及欧洲的EADS,达索、泰雷斯等航空业巨头便纷纷展示了各自开发的新型无人机,在预测报告中指出,从2005年到2014年,欧洲军用无人机市场的增长率将保持在11%的水平上,这期间的销售总额将达到49亿欧元(约合59.3亿美元)。  相似文献   
103.
The James Webb Space Telescope   总被引:4,自引:0,他引:4  
The James Webb Space Telescope (JWST) is a large (6.6 m), cold (<50 K), infrared (IR)-optimized space observatory that will be launched early in the next decade into orbit around the second Earth–Sun Lagrange point. The observatory will have four instruments: a near-IR camera, a near-IR multiobject spectrograph, and a tunable filter imager will cover the wavelength range, 0.6 < ; < 5.0 μ m, while the mid-IR instrument will do both imaging and spectroscopy from 5.0 < ; < 29 μ m.The JWST science goals are divided into four themes. The key objective of The End of the Dark Ages: First Light and Reionization theme is to identify the first luminous sources to form and to determine the ionization history of the early universe. The key objective of The Assembly of Galaxies theme is to determine how galaxies and the dark matter, gas, stars, metals, morphological structures, and active nuclei within them evolved from the epoch of reionization to the present day. The key objective of The Birth of Stars and Protoplanetary Systems theme is to unravel the birth and early evolution of stars, from infall on to dust-enshrouded protostars to the genesis of planetary systems. The key objective of the Planetary Systems and the Origins of Life theme is to determine the physical and chemical properties of planetary systems including our own, and investigate the potential for the origins of life in those systems. Within these themes and objectives, we have derived representative astronomical observations.To enable these observations, JWST consists of a telescope, an instrument package, a spacecraft, and a sunshield. The telescope consists of 18 beryllium segments, some of which are deployed. The segments will be brought into optical alignment on-orbit through a process of periodic wavefront sensing and control. The instrument package contains the four science instruments and a fine guidance sensor. The spacecraft provides pointing, orbit maintenance, and communications. The sunshield provides passive thermal control. The JWST operations plan is based on that used for previous space observatories, and the majority of JWST observing time will be allocated to the international astronomical community through annual peer-reviewed proposal opportunities.  相似文献   
104.
105.
The Electric and Magnetic Field Instrument and Integrated Science (EMFISIS) investigation on the NASA Radiation Belt Storm Probes (now named the Van Allen Probes) mission provides key wave and very low frequency magnetic field measurements to understand radiation belt acceleration, loss, and transport. The key science objectives and the contribution that EMFISIS makes to providing measurements as well as theory and modeling are described. The key components of the instruments suite, both electronics and sensors, including key functional parameters, calibration, and performance, demonstrate that EMFISIS provides the needed measurements for the science of the RBSP mission. The EMFISIS operational modes and data products, along with online availability and data tools provide the radiation belt science community with one the most complete sets of data ever collected.  相似文献   
106.
We review results about protoplanetary disk models, protoplanet migration and formation of giant planets with migrating cores. We first model the protoplanetary nebula as an α–accretion disk and present steady state calculations for different values of α and gas accretion rate through the disk. We then review the current theories of protoplanet migration in the context of these models, focusing on the gaseous disk–protoplanet tidal interaction. According to these theories, the migration timescale may be shorter than the planetary formation timescale. Therefore we investigate planet formation in the context of a migrating core, considering both the growth of the core and the build–up of the envelope in the course of the migration. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
107.
Like their sighted peers, many blind students in elementary, middle, and high school are naturally interested in space. This interest can motivate them to learn fundamental scientific, quantitative, and critical thinking skills, and sometimes even lead to careers in Science, Technology, Engineering, and Math (STEM) disciplines. However, these students are often at a disadvantage in science because of the ubiquity of important graphical information that is generally not available in accessible formats, the unfamiliarity of teachers with non-visual teaching methods, lack of access to blind role models, and the low expectations of their teachers and parents. We discuss joint efforts by the National Aeronautics and Space Administration (NASA) and the National Federation of the Blind’s (NFB) National Center for Blind Youth in Science (NCBYS) to develop and implement strategies to promote opportunities for blind youth in science. These include the development of tactile space science books and curriculum materials, science academies for blind middle school and high school students, and college-level internship and mentoring programs. The partnership with the NFB exemplifies the effectiveness of collaborations between NASA and consumer-directed organizations to improve opportunities for underserved and underrepresented individuals.  相似文献   
108.
2006年2月13日美国《每日防务》报道.美空军正在与澳大利亚、日本、新加坡和泰国等太平洋地区国家谈判.试图建立一个在该地区联合使用RQ-4”全球鹰”(Global Hawk)高空长航时侦察无人机系统、并分享其所获信息的集团。目前这些国家正与美太平洋空军部队(PACAF).就怎样才能分享到该机所获得的图像和情报数据.是否可以购买该无人机.是否可采购该无人机并由其他国家代为使用.是否可参与该无人机传感器的研制等问题进行讨论。PACAF司令官保罗&;#183;赫斯特(Paul Hester)将军表示,  相似文献   
109.
诺斯洛普&;#183;格鲁曼公司8月11日.在弗吉尼亚州的纽渡纽斯造船厂为新一代航空母舰CVN21的首舰CVN-78开始切割第一块钢板举行庆祝仪式.象征CVN21先期建造计划已经启动.这块钢板重选15吨,位置在CVN21的舵侧。  相似文献   
110.
The world's major space companies have undergone continual evolution, through a process of mergers and acquisitions, since their creation from their aerospace parents. Although much of this evolution occurred in the early years of the Space Age, the process seems to have become particularly dynamic in the 1990s, as companies have striven to become ever more competitive in an increasingly global business environment. This article reviews some of the most important mergers and traces the recent development of the world's leading space contractors.  相似文献   
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