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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   
52.
基于Vega的实时场景渲染技术研究   总被引:9,自引:0,他引:9  
视景仿真因其能够帮助人们建立一个具有身临其境的沉浸感 ,能与复杂系统进行交互 ,并能促进构想与创造环境 ,而成为社会各个应用领域发展中不可或缺的高科技手段。Vega用于虚拟现实和实时视景仿真软件的开发 ,提供了快捷和很容易就可构造出复杂应用程序的手段 ,可以很好地实现视景仿真的实时场景渲染 ,使虚拟场景更加逼真 ,在视景仿真领域有着广泛的应用  相似文献   
53.
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   
54.
固体推进剂羽焰红外辐射强度测试技术   总被引:1,自引:0,他引:1  
针对低特征信号推进剂研究的需要,研制了羽焰红外辐射测试系统,并进行了几种配方的推进剂羽焰红外辐射强度测试。该系统主要包括探测单元、光路系统、信号处理单元和自校准黑体等,测试精度优于4%,使用性能良好,能准确表征推进剂红外辐射的水平。  相似文献   
55.
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   
56.
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   
57.
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   
58.
Sun  Ming-Tsung  Chou  Dean-Yi  TON Team  the 《Space Science Reviews》2003,107(1-2):103-106
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   
59.
对大化肥斯那姆氨气提法工艺中使用的P101 A/B离心机高压泵出现的一系列故障进行了分析,找出了故障原因,并提出了具体的改进措施和建议。  相似文献   
60.
填充短纤维对NBR基绝热材料性能的影响   总被引:1,自引:4,他引:1  
研制了一种新型的无石棉丁腈橡胶(NBR)基内绝热材料。在对酚醛纤维、聚丙烯腈预氧化纤维、粘胶纤维、美塔斯纤维等几种短切纤维对比基础上,优选出酚醛纤雏作为绝热材料的抗烧蚀填充剂,并研究了其用量对材料抗烧蚀性能及力学性能的影响趋势及作用机理。结果显示当NBR中填充25份酚醛纤维时,绝热材料的线烧蚀率0.04mm/s,拉伸强度8.12MPa.断裂伸长率794%,密度1.114g/cm^3,综合性能良好。  相似文献   
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