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排序方式: 共有1322条查询结果,搜索用时 15 毫秒
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M.V. Klimenko V.V. Klimenko K.G. Ratovsky L.P. Goncharenko 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
In this paper, we use the modified GSM TIP model to explore how the thermosphere–ionosphere system in the American longitudinal sector responded to the series of geomagnetic storms on September 9–14, 2005. Comparison of modeling results with experimental data at Millstone Hill, USA (42.6°N, 71.5°W), Ramey, Puerto Rico (18.3°N, 66.8°W) and Jicamarca, Peru (11.9°S, 76.9°W) has shown a good agreement of ionospheric disturbances in the F-region maximum height. We examine in detail the formation mechanisms of these disturbances at different latitudes and describe some of the important physical processes affecting the behavior of the F-region. In addition, we consider the propagation of thermospheric wind surge and the formation of additional layers in the low-latitude ionosphere during geomagnetic storms. 相似文献
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《中国航空学报》2021,34(9):1-10
The full constellation of Chinese Global Navigation Satellite System (GNSS) BeiDou-3 has been deployed completely and started fully operational service. In addition to providing global Positioning, Navigation and Timing (PNT) services, the BeiDou-3 satellites transmissions can also be used as the sources of illumination for Earth Observation (EO) with a bistatic radar configuration. This innovative EO concept, known as GNSS reflectometry (GNSS-R), allows to measure the Earth surface characteristics at high resolution via the reflected L-band radar signals collected by a constellation of small, low cost and low Earth orbiting satellites. For the first time in orbit, earth reflected BeiDou-3 signal has been detected from the limited sets of raw data collected by the NASA’s Cyclone GNSS (CYGNSS) constellation. The feasibility of spaceborne BeiDou-3 reflections on two typical applications, including sea surface wind and flooding inundation detection, has been demonstrated. The methodology and results give new strength to the prospect of new spaceborne GNSS-R instruments and missions, which can make multi-GNSS reflectometry observations available to better capture rapidly changing weather systems at better spatio-temporal scales. 相似文献
826.
快速成形法及应用可能分析 总被引:2,自引:0,他引:2
郭永卫 《航空精密制造技术》1998,(1)
简要介绍快速成形技术和一种典型快速成形机的工作原理,并阐述了此技术的主要用途、应用方法及应用可行性分析。 相似文献
827.
王奇利 《西安航空技术高等专科学校学报》2010,28(1)
实验教学是学生获得知识和能力训练的重要途径,工程力学实验是工科院校学生的一门技术基础课。尝试利用现代网络技术和3Dmax软件,结合我校的力学实验课教学,开发一套基于网络的工程力学实验教学系统,作为对理论教学和实验室教学的补充,取得很好效果。 相似文献
828.
为掌握涡轴发动机排气中的冒烟数及芳香烃体积分数对冒烟数的影响,设计了某涡轴发动机冒烟数测量试验方案,通过在RP-3航空煤油中添加甲苯(C6H5CH3)获得不同芳香烃体积分数,开展发动机排气冒烟试验;并根据实测冒烟数(SN)拟合得到了与计算冒烟质量浓度指数(CI)的关系式。试验结果表明:某型涡轴发动机采用基准燃油时各状态冒烟数均小于40,优于设计指标;最大起飞状态下芳香烃体积分数每增加3%可导致冒烟数升高6%。该试验为涡轴发动机排气冒烟数测量和预估提供了一种有效方法,并为通过减少燃油中芳香烃体积分数来抑制发动机冒烟数提供了依据。 相似文献
829.
Chang'E-1 and Chang'E-2 of China's Lunar Exploration Program (CLEP) have successfully achieved their mission. At the present time, only Chang'E-3 is still in operation, which was successfully launched on December 2, 2013. Chang'E-3 probe is the third robotic lunar mission of CLEP, which consists of a lander and a rover, with eight payloads on board the spacecraft. Up to December 21, 2015, more than 2.86TB raw data were received from these instruments onboard Chang'E-3 probe. A series of research results have been achieved. This paper gives a detailed introduction to the new scientific results obtained from Chang'E-3 missions. 相似文献
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