共查询到15条相似文献,搜索用时 31 毫秒
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"大家好,欢迎来到2128年的国际太空家园,我是向导:NINGZEHAN,你们可以叫我N先生。现在,请让我带你们去太空家园看看吧。""我们现在来到的是中国建设的"红 相似文献
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笔者仅在此撷取陈泓主任的一席话作为编者按。你问钱学森空间技术实验室(以下简称钱室)做了什么事情?我们试图去做的事情很困难,尤其是在航天企业里,成功文化对我们的影响很大,也许我们的思维经常会这样问:你做的工作对型号到底有什么用?我们就是在类似"你们到底做出了啥东西"的质疑声中不断地孤独前行。钱室想走的是一条探索之路,需要足够的时间和耐心,希望通过你们的采访,把钱室真实地反映给读者:它不是完美无缺的,是一项仍需有很多改进的探索,现在需要的就是假以时日,留一些时间来完成这项探索,这是我最大的愿望。钱室作为创新的一个特区,需要来自方方面面的支持,包括像《国际太空》这样具有独立观点的媒体。我想,钱室就是来解决并践行"钱学森之问"的:我们为什么不能创新?我们该如何创新? 相似文献
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M. Prabhu K. Unnikrishnan 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2018,61(7):1672-1688
In the present work, we analyzed the daytime vertical E × B drift velocities obtained from Jicamarca Unattended Long-term Ionosphere Atmosphere (JULIA) radar and ΔH component of geomagnetic field measured as the difference between the magnitudes of the horizontal (H) components between two magnetometers deployed at two different locations Jicamarca, and Piura in Peru for 22 geomagnetically disturbed events in which either SC has occurred or Dstmax < ?50 nT during the period 2006–2011. The ΔH component of geomagnetic field is measured as the differences in the magnitudes of horizontal H component between magnetometer placed directly on the magnetic equator and one displaced 6–9° away. It will provide a direct measure of the daytime electrojet current, due to the eastward electric field. This will in turn gives the magnitude of vertical E × B drift velocity in the F region. A positive correlation exists between peak values of daytime vertical E × B drift velocity and peak value of ΔH for the three consecutive days of the events. It was observed that 45% of the events have daytime vertical E × B drift velocity peak in the magnitude range 10–20 m/s and 20–30 m/s and 20% have peak ΔH in the magnitude range 50–60 nT and 80–90 nT. It was observed that the time of occurrence of the peak value of both the vertical E × B drift velocity and the ΔH have a maximum (40%) probability in the same time range 11:00–13:00 LT. We also investigated the correlation between E × B drift velocity and Dst index and the correlation between delta H and Dst index. A strong positive correlation is found between E × B drift and Dst index as well as between delta H and Dst Index. Three different techniques of data analysis – linear, polynomial (order 2), and polynomial (order 3) regression analysis were considered. The regression parameters in all the three cases were calculated using the Least Square Method (LSM), using the daytime vertical E × B drift velocity and ΔH. A formula was developed which indicates the relationship between daytime vertical E × B drift velocity and ΔH, for the disturbed periods. The E × B drift velocity was then evaluated using the formulae thus found for the three regression analysis and validated for the ‘disturbed periods’ of 3 selected events. The E × B drift velocities estimated by the three regression analysis have a fairly good agreement with JULIA radar observed values under different seasons and solar activity conditions. Root Mean Square (RMS) errors calculated for each case suggest that polynomial (order 3) regression analysis provides a better agreement with the observations from among the three. 相似文献
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2010年3月19日,一部由奥斯卡获奖者莱昂那多·迪卡普里奥解说的3D影片<哈勃3D>与公众见面了,这部影片由美国航宇局、IMAX公司和华纳兄弟电影公司共同制作. 相似文献
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《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1999,23(5-6):1065-1074
A model of optically thin, advection-dominated accretion flows (ADAFs) has made rapid progress recently and attracted much attention now. It can nicely reproduce the observed spectra of Sgr A1 and other low-luminosity AGNs. We here review the unique properties of ADAFs, focusing on their emission properties and time-dependent behavior. The issues involved with ADAFs are also discussed. 相似文献
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Mehdi Akhoondzadeh Angelo De Santis Dedalo Marchetti Alessandro Piscini Gianfranco Cianchini 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2018,61(1):248-263
After DEMETER satellite mission (2004–2010), the launch of the Swarm satellites (Alpha (A), Bravo (B) and Charlie (C)) has created a new opportunity in the study of earthquake ionospheric precursors. Nowadays, there is no doubt that multi precursors analysis is a necessary phase to better understand the LAIC (Lithosphere Atmosphere Ionosphere Coupling) mechanism before large earthquakes. In this study, using absolute scalar magnetometer, vector field magnetometer and electric field instrument on board Swarm satellites, GPS (Global Positioning System) measurements, MODIS-Aqua satellite and ECMWF (European Centre for Medium-Range Weather Forecasts) data, the variations of the electron density and temperature, magnetic field, TEC (Total Electron Content), LST (Land Surface Temperature), AOD (Aerosol Optical Depth) and SKT (SKin Temperature) have been surveyed to find the potential seismic anomalies around the strong Ecuador (Mw = 7.8) earthquake of 16 April 2016. The four solar and geomagnetic indices: F10.7, Dst, Kp and ap were investigated to distinguish whether the preliminary detected anomalies might be associated with the solar-geomagnetic activities instead of the seismo-ionospheric anomalies. The Swarm satellites (A, B and C) data analysis indicate the anomalies in time series of electron density variations on 7, 11 and 12 days before the event; the unusual variations in time series of electron temperature on 8 days preceding the earthquake; the analysis of the magnetic field scalar and vectors data show the considerable anomalies 52, 48, 23, 16, 11, 9 and 7 days before the main shock. A striking anomaly is detected in TEC variations on 1 day before earthquake at 9:00 UTC. The analysis of MODIS-Aqua night-time images shows that LST increase unusually on 11 days prior to main shock. In addition, the AOD variations obtained from MODIS measurements reach the maximum value on 10 days before the earthquake. The SKT around epicentral region presents anomalous higher value about 40 days before the earthquake. It should be noted that the different lead times of the observed anomalies could be acknowledged based on a reasonable LAIC earthquake mechanism. Our results emphasize that the Swarm satellites measurements play an undeniable role in progress the studies of the ionospheric precursors. 相似文献