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181.
Hajime Fukushima Kazunori Suzuki Liping Li Naoya Suzuki Hiroshi Murakami 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
The tendency of over-estimation of sun-glint reflectance was found in GLI satellite ocean color data, after applying the traditional sun-glint model of Cox and Munk together with objective analysis wind data. ADEOS-II has provided a good opportunity to improve the glint model using data measured by GLI and SeaWinds, both onboard the satellite. With the help of simultaneous wind measurements achieved by SeaWinds, the Cox and Munk model is re-evaluated using GLI measurements to obtain a new relationship between the surface mean square slope and wind. The new model was found to be very close to the Cox and Munk under moderate wind speed but is much different under calm condition, where it shows similarity to the result reported by Ebuchi and Kizu. It also improves the ocean color data availability and the precision of sun-glint reflectance, based on the evaluation result of the generated Level 3 data products. 相似文献
182.
空气中一甲肼监测的固体吸附/分光光度法 总被引:1,自引:0,他引:1
研究了用固体吸附和分光光度监测空气中一甲肼浓度的方法,试验了标准气、采样管、比色酸度范围、温度、光强和干扰气对测试结果的影响。结果表明:以研制成的固体采样管富集采样,用对二甲氨基苯甲醛作显色剂,在470nm波长,2cm光径的比色皿,采集100L气样时,方法最低检出浓度为0.0031mg/m3,平均变异系数0.036,平均相对误差5.5%,测量范围为0.010mg/m3~2.50mg/m3。 相似文献
183.
高层大气模型对空间站轨道漂移和寿命的影响分析 总被引:2,自引:0,他引:2
本文以轨道摄动分析方法一阶理论为基础,其中大气阻力摄动采用数值积分方法,给出一种可利用各种大气模型进行轨道摄动分析的计算方法,并利用三种高层大气模型(CIRA—72,CIRA—86和DTM)和三个太阳活动水平(F10.7=100,150和200)分析比较了大气阻力振动对高度为400km的空间站轨道漂移和寿命的影响,以及估算修正轨道漂移所需的能量。给出的定量分析结果将为空间站或航天飞行器的轨道设计和能量估算提供依据。 相似文献
184.
185.
一种高效的计算卫星轨道寿命的方法 总被引:1,自引:0,他引:1
关于在大气阻力作用下卫星生存寿命的估计 ,提出了一种高效的数值方法 ,称为微分 -积分法。它的实质是以轨道要素的平均变化率为基础的微分方程 ,而方程的右端包含定积分。与传统方法比较验证了此新方法的正确性 ,并且显示了它的极高效率。在诸如空间碎片减缓这种需要非常大量的计算卫星寿命的问题中 ,新方法的价值得到充分体现。 相似文献
186.
Based on the measurements made by Atmospheric Density Detectors (ADDs) onboard Chinese spacecraft Shenzhou 2-4, the variations of thermosphere density are revealed. During the quiet period, the density at spacecraft altitude of 330~410km exhibited a dominant diurnal variation, with high value on dayside and low value on nightside. The ratio of the diurnal maximum density to the minimum ranged from 1.7 to 2.0. The ratio shows a positive correlation with the level of solar activity and a negative correlation with the level of geomagnetic activity. When a geomagnetic disturbance comes, the atmospheric density at the altitude of 330~410km displayed a global enhancement. For a strong geomagnetic disturbance, the atmospheric density increased by about 56%, and reached its maximum about 6~7 hours after the geomagnetic disturbance peak. The density asymmetry was also observed both in the southern and northern hemisphere during the geomagnetic disturbance peak. 相似文献
187.
This paper presents the recent progress of space environment research and service in China.During the past two years,many models of space environment forecast and analysis methods of space environment effects have been developed for tailored space environment service for Chinese space mission.A new Re-locatable Atmospheric Observatory(RAO)for monitoring atmospheric wind,temperature,density and pressure of the near space from 20 km up to 120 km altitudes is being constructed.In space environment service space environment safety was provided to ensure the safety of CE-1 for its launch and operation in 2007. 相似文献
188.
对返回式航天器进行变轨控制计算时要用到平均轨道周期变率,而数值法定轨通常求解的是大气阻力系数,无法直接得到平均轨道周期变率。文章通过建立航天器精密动力学模型、数值积分器、瞬时轨道根数到平均轨道根数的转换算法和平均周期序列多项式拟合算法,提出了一种基于数值法精密轨道确定和预报计算平均轨道周期变率的数值方法。 相似文献
189.
中高层大气风场和温度场星载探测技术研究进展 总被引:2,自引:2,他引:0
中高层大气风场和温度场是重要的大气基本参数, 其全球高精度测量具有广泛的应用前景, 探测需求日趋强烈. 干涉光谱仪由于其多通道、高通量和高光谱分辨率等优点而成为本项目的首选. 目前被成功应用的干涉式测风/测温仪器主要有Fabry-Perot 干涉仪和广角Michelson 干涉仪两大类. 本文对干涉光谱仪用于中高层大气风场和温度场探测的发展状况进行了分析, 同时比较了几种干涉仪测风和测温的可行性及优缺点, 为中国开展中高层大气风场和温度场星载探测打下基础. 相似文献
190.
V.P. Tritakis Yu.V. Pisanko A.G. Paliatsos G.K. Korbakis P.Th. Nastos 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
Relativistic electrons (with energies >150 keV) which originate in the outer radiation belt and detected by the Russian ‘Meteor’ series of satellites have been correlated with the atmospheric total ozone data compiled by almost 90 stations located around the world within the latitude zone 40°–70°N. In more than 60% of the stations examined we have detected a clear decrease of the ozone 3–5 days after the electron flux excess. A numerical model has been applied to approximate this effect based on relativistic electron initiated nitric oxides creation in the upper mesosphere with subsequent atmospheric transport (both vertical and horizontal) towards the upper stratosphere. A first attempt of local and temporal prediction of ozone depletion because of energetic electrons impact in the middle atmosphere has been illustrated. 相似文献