Space Shuttle UHF communications performance evaluation

Computational investigations and experimental measurements were performed to evaluate the Space Shuttle UHF communication system performance for payload bay antenna at the proposed new location. To insure adequate communication coverage at relocated new location, the link margin for the Extravehicular Activity (EVA) astronauts and between Space Shuttle Orbiter and International Space Station (SSO-ISS) during rendezvous were analyzed. The multipath effects from the vehicle structures surrounding the antenna were investigated. The Radio Frequency (RF) electromagnetic radiation to the Orbiter Docking System (ODS) pyrotechnics was also analyzed to ensure the EMC/EMI compliances.     

延长热电池寿命的途径探讨

从防空导弹地面电源－－热电池的热设计和工艺角度出发，分析影响电池工作寿命的因素，提出延长电池工作寿命的三条途径：合理控制热电池的内部热量；提高加热片的均匀性；合理选择外保温材料。实践证明，这些途径是可行的。     

Space experiment on behaviors of treefrog.

Japanese treefrogs (Hyla japonica) are planned to be sent to the space station MIR. Experimental system was developed to observe their behaviors under microgravity.     

Distance estimation at 60 GHz

An FM-CW radar front-end was fabricated in an integrated manner at 60 GHz by using the NRD guide. Main emphasis was placed on compactness in size and high-precise operation in performance. The fabricated radar consists of an FM Gunn oscillator, a balanced mixer, and a planar antenna fed by leaky NRD guide with a mechanically beam-scanning performance. All circuit components and the antenna were contained in a compact housing of 170 /spl times/ 140 mm in area and 25 mm in thickness, and thus, a thin type of millimeter-wave radar front-end was successfully developed. Moreover, an error of distance estimation was measured to be less than a distance of 0.7 m.     

Relationship between daily variation of cosmogenic nuclide Be-7 concentration in atmosphere and solar activities

Daily Be-7 concentrations in air at the height of 15 m are continuously observed at 38°15.2′N, 140°20.9′E, between 2000 and 2001. The average concentration and the relative standard deviation were 4.0 mBq/m³ and 50% in 2000–2001, respectively. The Be-7 concentrations increased 2.5% with the decrease in the sunspot numbers by 6.7% for the term of two years. From the power spectral analysis, the periodicity of 26 days is shown for the daily Be-7 concentrations. The folding analysis indicates that the time variation of the Be-7 concentration is similar to that of the ground-based neutron counting rate, and the phase delay for the minimum portion of Be-7 concentration was roughly 8 days to the maximum sunspot number. These results indicate that the Be-7 concentrations in the air at ground level have 26 day periodicity as a component of time variations and the time variation is caused by the solar modulation of galactic cosmic rays, which corresponds to the variation of the sunspot number due to the rotation of the sun.     

计算机辅助工时定额管理系统

介绍了南飞公司劳资处开发的计算机辅助工时定额管理系统的主要功能，系统特点及运行效果等。     

卫星交会的自主导航技术

论述卫星交会自主导航的飞行任务背景和概念 ,综述国内外学者正在进行探索研究的思路 ,以期引起国内学者的的注意、探讨和深入研究。     

浅论馆员素质中人文精神的体现

文章主要阐述了馆员素质中人文精神的具体表现,以及如何提高馆员的自身修养、素质,使读者在馆员的身上看到人文精神的光彩,人文关怀的温情,使他们对学习充满信心和希望,对知识渴求更加强烈。     

CBERS-1卫星红外多光谱扫描仪扫描子系统

文章介绍了CBERS -1卫星红外多光谱扫描仪(IRMSS)关键部件扫描子系统研制与应用情况。