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1.
The Large Angle Spectrometric Coronagraph (LASCO) and Extreme-ultraviolet Imaging Telescope (EIT) onboard Solar and Heliospheric Observatory (SOHO) provide us with unprecedented multi-wavelength observations helping us to understand different dynamic phenomena on the Sun and in the corona. In this paper we discuss the association between post-eruptive arcades (PEAs) detected by EIT and white-light coronal mass ejections (CMEs) detected by LASCO/C2 telescope.  相似文献   
2.
土压缩模量预测回归分析方法   总被引:1,自引:0,他引:1  
在土压缩模量Es的分析计算中,常用的分析方法是根据土的e-p曲线试验资料建立公式求解,本文引入了数学上的回归分析方法来探讨Es与其它各项物理力学指标参数之间的相关关系,旨在找出对Es影响最显著的指标参数,并建立最优回归方程式,以此来预测Es。研究结果表明:该方法通用性强,应用范围广,亦可推广应用于其它相关领域。  相似文献   
3.
断层网络可视为一浅源构造地震的蕴震系统。地震前兆是该系统在演化过程中所表现出来的复杂的整体动态行为,是蕴震系统自组织演化的构造微动态。本文从信息合成观点出发,提出了方向信息合成方法(DirectionInformationSynthesis)。对京、津、唐地区50条跨断层地形变观测时间序列的计算表明:断层网络活动的方向特征(相对张、压、扭动等)临震前出现了运动方式(方向)群体优势异常;该异常可能具有可重复性,该方向特征的时空演化可视为一个自组织过程。  相似文献   
4.
日珥上升运动和日冕物质抛射的关系   总被引:1,自引:0,他引:1  
吴桂平  许敖敖 《天文学报》1997,38(2):160-166
本文基于观测日珥上升运动与日冕物质抛射(CME)之间的紧密联系和我们对日珥动力学特征的理解,探讨了在背景场作用下,日珥上升时其上方盔状冕流的动力学演化规律;分析了1980年8月18日爆发日珥与对应的CME事件之间的内在关系.结果表明:(1)缓慢上升的日珥只引起盔状冕流缓慢演化;(2)加速上升日珥的加速度和末速度的大小决定形成CME事件的激烈程度;(3)CME事件的能量可能来源于爆发日环释放的磁能.理论分析与观测结果基本一致.  相似文献   
5.
Here we present a preliminary analysis of a helical eruptive prominence at the east limb of the Sun on 21 April 2001. Unusually this eruption is associated with a double CME. We have tried to study the morphology of the event, energy budget of the prominence and associated CMEs. Our analysis shows that the prominence and first CME started simultaneously from the limb and prominence carries sufficient energy to feed both the CMEs. Moreover, it is also concluded that CMEs are magnetically driven and internally powered.  相似文献   
6.
一个拱桥状爆发日珥   总被引:2,自引:2,他引:0  
1991年3月7日在太阳东北边缘产生了一个爆发日珥。它产生在没有耀斑、暗条、黑子等其它太阳活动现象的一个相对宁静的日面区域。日珥抛射的最大高度为6.97×104km,最大长度为11.6×104km,从形态的大小来看它属于中等偏小的爆发日珥。抛射的时间过程,上升阶段非常快,而下降阶段则较缓慢,有类似于耀斑爆发的时间过程。日珥爆发后的绝大部分物质基本上在磁场作用下沿磁力线作抛物线运动形成拱桥形状,并保持到消失。日珥下降前后,顶端有少部分物质被抛射脱离日珥主体部分,扩散到行星际空间。  相似文献   
7.
The purpose of this paper is to propose a new notion on prominent areas of a city defined by two types of comprehensive prominence for identifying urban spatial structure. Not only geometric attributes and topological attributes but also thematic attributes of irregular areas (e.g. districts of a city) are used to define these indices. In the paper, first the topological prominence related to geometric attributes such as size, location, and shape of areas is constructed by spatial weight matrix. Second, for finding comprehensive prominences, the principle axis factor model is adopted, and the first factor score is defined as the comprehensive prominence 1. Then, the proportion of thematic attributes of each area occupied in across the city is used to define the comprehensive prominence 2. Finally, we use these comprehensive prominences to extract some important regions in Matsudo City of Chiba Prefecture in Japan. The areas composing those regions show a high topological prominence, have a large population, have many offices, and are located around the train station.  相似文献   
8.
Hinode is an observatory‐style satellite, carrying three advanced instruments being designed and built to work together to explore the physical coupling between the photosphere and the upper layers for understanding the mechanism of dynam‐ ics and heating. The three instruments aboard are the Solar Optical Telescope (SOT), which can provide high‐precision photometric and polarimetric data of the lower atmosphere in the visible light (388–668 nm) with a spatial resolution of 0.2–0.3 arcseconds, the X‐Ray Telescope (XRT) which takes a wide field of full sun coverage X‐ray images being capable of diagnosing the physical condition of coronal plasmas, and the EUV Imaging Spectrometer (EIS) which observes the upper transition region and coronal emission lines in the wavelength ranges of 17–21 nm and 25–29 nm. Since first‐light observations in the end of October 2006, Hinode has been continuously providing unprecedented high‐quality solar data. We will present some new findings of the sun with Hinode, focusing on those from SOT (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
9.
We have observed an eruptive prominence at the east solar limb on 25 January 1991 which started earlier than 0623 UT and was associated with a limb flare (S16 E90) of class 1B/ X10.0. We have recorded a huge mass ejection in the corona by the limb flare associated eruptive prominence. The eruptive prominence ejected a part of the loop in the corona with maximum speed of about 1280 km/sec. The ejected material attain height upto 150,000 km in the corona and finally faded/disappeared in the corona. During the ascending phase of the prominence material in the corona there was a unscrewing of the loop system associated with the eruptive prominence. The type II, III, and IV radio bursts were also reported by a number of Radio Observatories during observation of the eruptive prominence. The high flux of sudden ionospheric disturbances and the solar radio emissions on fixed frequencies (245–80000 MHz) were also recorded. The eruptive prominence associated with limb flare also shows increased proton flux (>10 MeV) during its occurence. The flare was classified as X10.0 flare. In this paper we have analysed the observed data and compared it with the theoretical model of the solar flare.On leave from his original Institute  相似文献   
10.
分析了1991年3月7日太阳东北边缘一个拱桥状爆发日珥上升、下降和半径膨胀的运动情况。该日珥的上升阶段和下降的开始阶段高度随时间的变化比较迅速,而且基本是线性的变化,但在下降的结束阶段则比较缓慢,也基本是线性的变化。它的下降运动不仅受到重力作用自由下落,而且还受到不均匀的大气阻力,磁场等力的共同作用而下落。而速度,喷射出以后总的在逐渐减弱,上升阶段减弱较快。下降阶段初期有一次跳跃式的变化,先迅速减弱,然后又很快增加,在下降后期速度减弱较慢。日珥到达最大高度的时间比日珥半径膨胀到达最大尺度的时间早4min左右。上升下降速度最大时半径膨胀速度最小,而上升下降速度最小时半径膨胀的速度最大。  相似文献   
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