全文获取类型
收费全文 | 63篇 |
免费 | 14篇 |
国内免费 | 2篇 |
专业分类
航空 | 39篇 |
航天技术 | 25篇 |
综合类 | 1篇 |
航天 | 14篇 |
出版年
2023年 | 2篇 |
2021年 | 1篇 |
2020年 | 3篇 |
2019年 | 3篇 |
2017年 | 1篇 |
2015年 | 1篇 |
2014年 | 3篇 |
2013年 | 6篇 |
2012年 | 1篇 |
2011年 | 5篇 |
2010年 | 7篇 |
2009年 | 5篇 |
2008年 | 4篇 |
2007年 | 6篇 |
2006年 | 3篇 |
2005年 | 5篇 |
2004年 | 1篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1998年 | 4篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 4篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 3篇 |
1991年 | 1篇 |
1989年 | 1篇 |
排序方式: 共有79条查询结果,搜索用时 31 毫秒
21.
CHEN Zeyu CHEN Hongbin XU Jiyao BIAN Jianchun QIE Xiushu Lü Daren CHEN Wen REN Rongcai ZHANG Shaodong DOU Xiankang LI Tao HU Xiong HU Yongyun TIAN Wenshou 《空间科学学报》2014,34(5)
In this report we summarize the research results by Chinese scientists in 2012–2014. The focuses are placed on the researches of the middle and upper atmosphere, specifically the researches related to ground-based observation capability development, dynamical processes, the property of circulation and chemistry-climate coupling of the middle atmospheric layers. 相似文献
22.
23.
V. Korepanov G. Lizunov O. Fedorov Yu. Yampolsky V. Ivchenko 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,42(9):1515-1522
The IONOSAT project (from IONOspheric SATellites) is proposed by National Space Agency of Ukraine for First European Space Program as a part of Space Weather (SW) Program. As it is commonly accepted, Space Weather means the changes of the conditions on the Sun, in solar wind, magnetosphere and ionosphere which may affect the operation and reliability of on-board and ground technological systems and threaten human health. In this chain ionosphere is specific and integral part of SW formation. Moreover, namely in the ionosphere main part of the energy absorption of Sun-activated sporadic corpuscular and radiation fluxes takes places. The excitation of ionosphere by falling fluxes produces its “luminescence” in wide frequency band – from ULF waves till ultraviolet – and by this ionosphere works as an efficient “screen” or SW indicator.A goal of the proposed project is long-term spatial–temporal monitoring of main field and plasma parameters of ionosphere with aim to further develop fundamental conceptions of solar-terrestrial connections physics, nowcasting and forecast of SW, and diagnostics of natural and technogenic hazards with the help of scientific payload installed on-board a cluster of 3 low-Earth orbit (LEO) microsatellites (tentative launch date – 2012 year).The state of the project proposal and realization plans are discussed. 相似文献
24.
25.
探讨了绕月探测工程中北京航天飞行控制中心国际联网系统的监控方式,提出几种实时系统的监控方式并予以实现。同时结合实时代理(Agent)的体系结构,实现了通过UDP网络包及共享文件内存方法对SLE用户端的远程监控。 相似文献
26.
为给出某型航空发动机机载振动监测测振点较为合理的选择方案,基于转子支承和传力特点以及该型发动机实测振动信号的分析对比,定性和定量分析了各测点振动信号对于结构故障的反映和敏感程度。得出三个测振点能够比较真实客观地反映该型发动机的振动情况,但对于不同部件的振动敏感程度各测点又有所侧重的结论。即前测点主要反映低压压气机的振动;中测点综合反映高低压转子的振动,对以高压压气机为主导的组合故障反应更为敏感;后测点主要反映低压涡轮的振动,一定程度反映高压转子的振动,对以涡轮部件为主导的组合故障反应更为敏感。结合13台次故障发动机试车台振动测试超限报警结果的统计,给出了机载测振点较为合理的选择方案。若采用单点测振应重点考虑后测点,若采用两点测振应一个为前测点,一个为后测点。 相似文献
27.
文章通过天线罩倾斜时所产生的反射波对一种导航系统相控阵扫描天线监测系统影响的分析,得到了监测系统的监测角漂移与天线罩倾斜角及距离的关系,并提出解决监测角漂移问题的思路. 相似文献
28.
T. Bullett A. Malagnini M. Pezzopane C. Scotto 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
In November 2008, the ionosonde station at Boulder, Colorado, USA (40.0°N; 105.3°W) became the host of a new ionosonde (VIPIR, Vertical Incidence Pulsed Ionospheric Radar) developed and built by Scion Associates. 相似文献
29.
30.
Carlo Scotto 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
An electron density profile model with free parameters is introduced. Initially the parameters are calculated on the basis of the ionospheric characteristics automatically obtained from the ionograms by Autoscala and considering the helio-geophysical conditions. The technique used to adjust the free parameters to the particular ionograms recorded is presented. 相似文献