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81.
Solar transients and their related interplanetary counterparts have severe effects on the space environments of the Earth. Therefore, the research of solar corona and interplanetary physics has become the focus of study for both solar and space scientists. Considerable progress has been achieved in these aspects by the solar and space physics community of China during 2012–2014, which will be given in this report. The brief report summarizes the research advances of solar corona and interplanetary physics into the following parts: solar wind origin and turbulence, coronal waves and seismology, solar eruptions, solar energetic particle and galactic cosmic ray, magnetic reconnection,Magnetohydrodynamic(MHD) models and their applications, waves and structures in solar wind,propagation of ICMEs/shocks and their arrival time predictions. These research achievements have been achieved by Chinese solar and space scientists independently or via international collaborations.  相似文献   
82.
In this paper we research the relationship between solar activity and the weather on Earth. This research is based on the assumption that every ejection of magnetic field energy and particles from the Sun (also known as Solar wind) has direct effects on the Earth’s weather. The impact of coronal holes and active regions on cold air advection (cold fronts, precipitation, and temperature decrease on the surface and higher layers) in the Belgrade region (Serbia) was analyzed. Some active regions and coronal holes appear to be in a geo-effective position nearly every 27 days, which is the duration of a solar rotation. A similar period of repetitiveness (27–29 days) of the passage of the cold front, and maximum and minimum temperatures measured at surface and at levels of 850 and 500 hPa were detected. We found that 10–12 days after Solar wind velocity starts significantly increasing, we could expect the passage of a cold front. After eight days, the maximum temperatures in the Belgrade region are measured, and it was found that their minimum values appear after 12–16 days. The maximum amount of precipitation occurs 14 days after Solar wind is observed. A recurring period of nearly 27 days of different phases of development for hurricanes Katrina, Rita and Wilma was found. This analysis confirmed that the intervals of time between two occurrences of some particular meteorological parameter correlate well with Solar wind and A index.  相似文献   
83.
基于多重Morphin算法,建立了终端区 三维实时改航方法。该方法首先根据航空器当前飞行状态按不同的转弯角和爬升/下滑角生 成一组弧线,随后在每条弧线的末端按同样方式反复运行,形成若干条由弧线组成的路径, 最后对所有路径进行综合评估,找到当前时刻的改航路径。算例分析表明,该方法提供的改 航路径可以保证航空器运行的安全与高效,在危险天气出现时更加充分地利用终端区空域资 源,同时计算时间短、可行性高。  相似文献   
84.
国外空间天气保障能力建设及对我国的启示   总被引:1,自引:0,他引:1  
文章对空间天气保障能力的科学内涵进行了分析,总结了国外相关发展现状,建议我国应从战略上高度重视空间天气保障能力发展,并从加大宣传力度、建设监测体系、提高预报水平、研究应对策略、注重人才队伍等方面进行了对策思考。  相似文献   
85.
《中国航空学报》2021,34(5):129-144
The air traffic management automation imposes stringent requirements on the weather models, in such a way that they should be able to provide reliable short-time forecasts in digital formats in almost real time. The atmospheric boundary layer is one of the regions where aircraft operation and coordination are critical and therefore atmospheric model performance is also vital. This paper presents conventional and innovative techniques to improve the accuracy in the forecasting of winds in the lower atmospheric layer, proposing mechanisms to develop better models including deterministic and stochastic simulations. Accuracy is improved by optimizing the grid, assimilating observations in cycling simulations and managing a number of ensemble members. An operation-driven post-processing stage helps to incorporate detailed terrain definitions and real-time observations without re-running the model. The improvements are checked against mesoscale weather simulations at different scales and a dedicated flight campaign. The results show good performance of the model without sensitively increasing the required throughput.  相似文献   
86.
This paper reviews various progresses on the ionospheric studies by the scientists in China during the last two years.The main contents concern the 4 aspects of the ionospheric re-search:(1) ionospheric weather and coupling with magnetosphere(polar and auroral ionosphere,ionospheric response to substorms,ionospheric storms);(2) mid-and low-latitude ionospheric clima-tology(ionospheric properties,yearly variations and solar activity dependence,long term variation);(3) ionospheric coupling with neutral atmosphere(gravity waves,tides,planetary waves,background upper atmosphere,and ionospheric response);and(4) ionospheric diagnostics(observation,modeling,and prediction).  相似文献   
87.
中国月球及深空空间环境探测   总被引:1,自引:0,他引:1       下载免费PDF全文
深空探测承载着人类航天技术发展、探索宇宙奥秘和寻找地外生命及人类宜居地的重任,成为各航天大国关注的热点。我国月球与深空探测虽然起步晚,但起点高,正在追赶并将实现领先。简要回顾了我国月球及深空空间环境探测的载荷情况、数据结果、理论和应用研究成果,简述了当前在研的自主火星空间环境探测目标以及规划中的未来深空探测任务,并根据当前国际发展态势,及我国在研、规划中的月球及深空探测任务情况,分析了我国月球及深空空间环境探测的关键科学问题、载荷技术发展趋势、理论与模拟的研究需求,最后对深空环境探测进行了展望。  相似文献   
88.
We extend the empirical coronal mass ejection (CME) arrival model of Gopalswamy et al. [Gopalswamy, N. et al. Predicting the 1-AU arrival times of coronal mass ejections, J. Geophys. Res. 106, 29207, 2001] to predict the 1-AU arrival of interplanetary (IP) shocks. A set of 29 IP shocks and the associated magnetic clouds observed by the Wind spacecraft are used for this study. The primary input to this empirical shock arrival model is the initial speed of white-light CMEs obtained using coronagraphs. We use the gas dynamic piston–shock relationship to derive the ESA model which provides a simple means of obtaining the 1-AU speed and arrival times of interplanetary shocks using CME speeds.  相似文献   
89.
The cross correlation of daily values of coronal hole areas at the eastern limb of the Sun constructed from the ground based measurements of the green coronal line and daily mean cosmic ray intensities over long time periods shows asymmetry: at the maximum of their 27 day cycle, cosmic ray intensities are better correlated with coronal hole areas 66 days before than with the current value. This indicates the potential for using coronal emission data as one of the parameters for eventual prediction of the level of cosmic ray flux at neutron monitor energies.  相似文献   
90.
卫星帆板转动和自身颤动会导致太阳X射线-极紫外射线(X-EUV)成像望远镜的成像质量下降.用移动补偿系统控制相机的CCD驱动器,使势阱转移到相邻相的位置上,转移的方向正好与图像在传感器上移动方向一致,使得图像的每个光子在移动后仍然落入传感器的同一个势阱内,补偿由于帆板移动造成的图像偏移.CCD相移沿列的方向进行,而CCD的列平行于东西向.高精度太阳敏感器使用两轴直角坐标来定位太阳的位置.移动补偿系统只使用其中一个轴向数据,由于南北指向误差远远小于东西指向,因此不对南北指向补偿.该移动补偿系统利用高精度太阳敏感器构成半闭环控制系统,通过偏移CCD势阱来实现一个方向上的移动补偿.该方案可以在不增加成本的前提下,消除长时间曝光过程中的太阳的平移和帆板颤动对图像质量造成的影响,扩大动态观测范围.   相似文献   
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