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51.
Kamide Y. Kihn E.A. Ridley A.J. Cliver E.W. Kadowaki Y. 《Space Science Reviews》2003,107(1-2):307-316
We report the recent progress in our joint program of real-time mapping of ionospheric electric fields and currents and field-aligned
currents through the Geospace Environment Data Analysis System (GEDAS) at the Solar-Terrestrial Environment Laboratory and
similar computer systems in the world. Data from individual ground magnetometers as well as from the solar wind are collected
by these systems and are used as input for the KRM and AMIE magnetogram-inversion algorithms, which calculate the two-dimensional
distribution of the ionospheric parameters. One of the goals of this program is to specify the solar-terrestrial environment
in terms of ionospheric processes, providing the scientific community with more than what geomagnetic activity indices and
statistical models provide.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
52.
53.
The Meridian Project is a ground-based network program to monitor solar-terrestrial space environment, which consists of a chain of 15 ground-based observatories located roughly along 120°E longitude and 30°N latitude. The Meridian project started in 2008, and its construction was completed by 2011. The integration and test phase of the Meridian Project conducted in 2011 demonstrated its observation capabilities as expected. The project will be in full operation in 2012. This report gives an overview of the recent development and preliminary results of the Meridian Project since 2010. 相似文献
54.
天气季节性影响的终端区空域容量分布 总被引:1,自引:0,他引:1
为了能将预测天气的概率信息加人流量管理的决策中,提高航空公司航班计划的有效性和准确性,利用具体机场历史天气数据,对该机场终端区影响容量的天气使用聚类算法进行分类,提出了对应于概率天气预报的概率容量分布模型。通过该模型,对终端区天气数据进行分析计算,然后使用遗传算法得出机场终端区天气季节性影响的容量。通过对成都双流国际机场终端区天气数据进行分析计算,计算结果与实际运行数字误差不大。 相似文献
55.
56.
卫星帆板转动和自身颤动会导致太阳X射线-极紫外射线(X-EUV)成像望远镜的成像质量下降.用移动补偿系统控制相机的CCD驱动器,使势阱转移到相邻相的位置上,转移的方向正好与图像在传感器上移动方向一致,使得图像的每个光子在移动后仍然落入传感器的同一个势阱内,补偿由于帆板移动造成的图像偏移.CCD相移沿列的方向进行,而CCD的列平行于东西向.高精度太阳敏感器使用两轴直角坐标来定位太阳的位置.移动补偿系统只使用其中一个轴向数据,由于南北指向误差远远小于东西指向,因此不对南北指向补偿.该移动补偿系统利用高精度太阳敏感器构成半闭环控制系统,通过偏移CCD势阱来实现一个方向上的移动补偿.该方案可以在不增加成本的前提下,消除长时间曝光过程中的太阳的平移和帆板颤动对图像质量造成的影响,扩大动态观测范围. 相似文献
57.
Sophie Pireaux Pascale Defraigne Laurence Wauters Nicolas Bergeot Quentin Baire Carine Bruyninx 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
The stability of GPS time and frequency transfer is limited by the fact that GPS signals travel through the ionosphere. In high precision geodetic time transfer (i.e. based on precise modeling of code and carrier phase GPS data), the so-called ionosphere-free combination of the code and carrier phase measurements made on the two frequencies is used to remove the first-order ionospheric effect. In this paper, we investigate the impact of residual second- and third-order ionospheric effects on geodetic time transfer solutions i.e. remote atomic clock comparisons based on GPS measurements, using the ATOMIUM software developed at the Royal Observatory of Belgium (ROB). The impact of third-order ionospheric effects was shown to be negligible, while for second-order effects, the tests performed on different time links and at different epochs show a small impact of the order of some picoseconds, on a quiet day, and up to more than 10 picoseconds in case of high ionospheric activity. The geomagnetic storm of the 30th October 2003 is used to illustrate how space weather products are relevant to understand perturbations in geodetic time and frequency transfer. 相似文献
58.
The Meridian Project is a ground- based network program to monitor solar-terrestrial space environment, which consists of a chain of ground-based observatories with multiple instruments including magnetometers, ionosondes, HF and VHF radar, Lidar, IPS monitors, sounding rockets etc. The chain is mainly located in the neighborhood of 120°E meridian, and is thus named the Meridian Project. It has officially been approved by the Chinese government and will be finished by 2009. This talk will give an overview of the Meridian Project and the proposed International Space Weather Meridian Circle Program. 相似文献
59.
The Chinese Meridian Space Weather Monitoring Project (Meridian Project for short) is a ground-based geospace monitoring chain in China. It consists of a chain of 15 ground-based observatories located roughly along 120°E longitude and 30°N latitude. Each observatory is equipped with multiple instruments to measure key parameters such as the baseline and time-varying geomagnetic field, the middle and upper atmosphere and ionosphere from about 20 to 1000km. This project started collecting data in 2012. Here a brief overview of the Chinese Meridian Project is given, and most recent science results mainly in the ionospheric and atmospheric studies are presented. 相似文献
60.
危险天气下基于多重Morphin算法的终端区三维实时改航方法 总被引:2,自引:1,他引:1
基于多重Morphin算法,建立了终端区三维实时改航方法。该方法首先根据航空器当前飞行状态按不同的转弯角和爬升/下滑角生成一组弧线,随后在每条弧线的末端按同样方式反复运行,形成若干条由弧线组成的路径,最后对所有路径进行综合评估,找到当前时刻的改航路径。算例分析表明,该方法提供的改航路径可以保证航空器运行的安全与高效,在危险天气出现时更加充分地利用终端区空域资源,同时计算时间短、可行性高。 相似文献