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排序方式: 共有105条查询结果,搜索用时 15 毫秒
51.
论高校医院与全科医学 总被引:1,自引:0,他引:1
摘 要 保证高校教职工、大学生的身心健康,是高校医院义不容辞的责任。为此,应探索一条更适合高校实际情况的医疗模式。本文就高校医院应如何为师生员工提供全方位的医疗保健服务进行了初步探讨。 相似文献
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基于主成分分析的混合象元分解 总被引:2,自引:0,他引:2
本文主要介绍基于主成分分析的混合象元分解。通常,主成分分析用于图象增强和数据空间维数的压缩,不改变数据的空间结构。文中引入了目标检验方法,利用它可达到对混合象元的分解。由于卫片的分辨率有限,混合象元大量存在于遥感图象中,而混合象元的存在是导致异物同谱和同物异谱的一个重要原因。若能实现混合象元的分解,就可为深入应用遥感资料提供有力帮助。 相似文献
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S. Dasso H. Asorey For The Pierre Auger Collaboration 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2012
The impact of the solar activity on the heliosphere has a strong influence on the modulation of the flux of low energy galactic cosmic rays arriving at Earth. Different instruments, such as neutron monitors or muon detectors, have been recording the variability of the cosmic ray flux at ground level for several decades. Although the Pierre Auger Observatory was designed to observe cosmic rays at the highest energies, it also records the count rates of low energy secondary particles (the scaler mode) for the self-calibration of its surface detector array. From observations using the scaler mode at the Pierre Auger Observatory, modulation of galactic cosmic rays due to solar transient activity has been observed (e.g., Forbush decreases). Due to the high total count rate coming from the combined area of its detectors, the Pierre Auger Observatory (its detectors have a total area greater than 16,000 m2) detects a flux of secondary particles of the order of ∼108 counts per minute. Time variations of the cosmic ray flux related to the activity of the heliosphere can be determined with high accuracy. In this paper we briefly describe the scaler mode and analyze a Forbush decrease together with the interplanetary coronal mass ejection that originated it. The Auger scaler data are now publicly available. 相似文献
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A 9.0 magnitude earthquake hit the east coast of Honshu, Japan (38.23°N and 143.19°E) on March 11, 2011. A massive tsunami trig- gered by the earthquake led to causalities, 相似文献
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Li Suju National Disaster Reduction Center of China the Ministry of Civil Affairs of China 《中国航天(英文版)》2011,(3):2-5
Natural disasters are common threats to all human beings. With the background of global climate change, major natural disasters have occurred frequently in the last few years and caused heavy casualties with high property losses. Satellite Earth ob-servation has been playing a more and more important role in monitoring and 相似文献
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We describe the present status of the project of the Taiwan Oscillation Network (TON) and discuss a scientific result using
the TON data. The TON is a ground-based network to measure solar intensity oscillations for the study of the solar interior.
Four telescopes have been installed in appropriate longitudes around the world. The TON telescopes take K-line full-disk solar
images of diameter 1000 pixels at a rate of one image per minute. The data has been collected since October of 1993. The TON
high-spatial-resolution data are specially suitable for the study of local properties of the Sun. In 1997 we developed a new
method, acoustic imaging, to construct the acoustic signals inside the Sun with the acoustic signals measured at the solar
surface. From the constructed signals, we can form intensity map and phase-shift map of an active region at various depths.
The direct link between these maps and the subsurface wave-speed perturbation suffers from the poor vertical resolution of
acoustic imaging. Recently an inversion method has been developed to invert the measured phase travel time perturbation to
estimate the distribution of wave-speed perturbation based on the ray approximation. This technique of acoustic imaging has
been used to image the far-side of the Sun that could provides information on space weather prediction.
The TON Team includes: Antonio Jimenez (Instituto Astrofisica de Canarias, Spain); Guoxiang Ai and Honqi Zhang (Huairou Solar
Observing Station, P.R.C.); Philip Goode and William Marquette (Big Bear Solar Observatory, U.S.A.); Shuhrat Ehgamberdiev
and Oleg Ladenkov (Ulugh Beg Astronomical Institute, Uzbekistan)
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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