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Y. Yan J. Huang B. Chen Y. Liu C. Tan 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
Radio bursts with fine structures in decimetric–centimetric wave range are generally believed to manifest the primary energy release process during flare/CME events. By spectropolarimeters in 1–2 GHz, 2.6–3.8 GHz, and 5.2–7.6 GHz at NAOC/Huairou with very high temporal (1.25–8 ms) and spectral (4–20 MHz) resolutions, the zebra patterns, spikes, and new types of radio fine structures with mixed frequency drift features are observed during several significant flare/CME events. In this paper we will discuss the occurrence of radio fine structures during the impulsive phase of flares and/or CME initiations, which may be connected to the magnetic reconnection processes. 相似文献
753.
Shun Liu Hagiwara H. Shoji R. Tamara H. Okano T. 《Aerospace and Electronic Systems Magazine, IEEE》2004,19(11):3-11
A complete grasp of the actual vessel traffic flow by accurate observation is essential to carry out vessel traffic management, design of vessel traffic route, plan of port construction, etc. Up to now, the observation of vessel traffic has needed many efforts such as the use of a special ship or car equipped with radar observation systems and the observation staff preparation for a considerably long period. In order to perform accurate observation of vessel traffic without such efforts, the authors have developed a completely automated radar network system covering the main traffic route of Tokyo Bay. In August 2003, as the second remote radar station attaching AIS equipment was set at East Ogishima (the first was installed at the National Defense Academy in 2002), the observing range could be enlarged and cover most traffic routes in Tokyo Bay. These two radars can observe the vessel traffic in Tokyo Bay simultaneously so as to know the traffic flow accurately on the basis of analyzing the integrated radar data. In addition to the development of a radar network system, the software to analyze observed vessel traffic flow has been developed. This software has various functions such as tracking of ship's position, automatic determination of ship's size, animation of ship's movements, superposition of successive radar images, display of ship's tracks, calculation of ship's speed distribution, extraction of dangerous ship encounters using subjective judgment value and bumper model, etc. Some analyzed results on vessel traffic flow observed by the remote radars in January and September 2003 are shown in this paper. 相似文献
754.
介绍一种以线性调频半导体激光为光源的衍射光栅干涉仪。激光与光栅上衍射的±1级衍射波会合,由于有光程差而发生光拍频,测量拍频信号的相位移则可测得光栅的位移。设计了一种克服激光波长漂移和空气折射率变化影响的对称差动光路,使这种方法达到实用化的程度,分辨力达到纳米级。此外,还介绍了应用于接触干涉仪的实验情况。 相似文献
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Rain Liu 《中国航天(英文版)》2012,(1):9
On December 27,2011,Ran Chengqi,director of the China Satellite Navigation Office announced that,the BeiDou Navigation Satellite System (BeiDou system) had that day begun to provide initial operational service. 相似文献
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杨柳 《桂林航天工业高等专科学校学报》2009,14(4):492-493
《思想道德修养与法律基础》课是针对大学生成长过程中面临的思想道德和法律问题,有效地开展科学的人生观、价值观、道德观和法制观的教育,引导大学生树立高尚的理想情操、养成良好的道德素质和较强的法律意识的一门课程。要想在教育教学过程中充分体现该门的吸引力和实效性,需要引入参与式教学法。本文仅就参与式教学的具体做法谈谈个人感受。 相似文献
759.
不确定度评定的一种新方法──最大方差法 总被引:3,自引:0,他引:3
研究了不确定度评定的新方法──最大方差法,分析了它的原理,列出了最大方差法用表,举例说明了它的应用。 相似文献
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