Variability and origin of permanent radio emission in RS CVn and Algol type binaries

The variability of the radio emission of RS CVn and Algol type binaries has been observed over 70 hours by Lefèvre et al. (1993). In this contribution simple model calculations are applied to discuss the relevant time scales. It is concluded that a significant fraction of the permanent radio emission of these systems is due to flare-like processes of energy release over a wide range of energies.     

用地球磁场和重力场成功挽救风云一号（B）卫星的控制技术

风云一号气象卫星是我国最早成功发射的太阳同步三轴稳定对地遥感卫星，由于早期的技术和器件原因，星上计算机因空间辐照而失控，造成星上贮气耗尽、卫星高速翻滚。本文详细介绍了了在卫星面临失败的情况下，作者利用地球磁场和重力场与卫星的相互作用，采用星上的磁力矩器和可用的一切手段而设计的一整套抢救这颗卫星的技术方法，并简述了经过75天的艰苦努力，使这颗濒临失败的卫星重新建立三轴稳定的对地定向姿态的历程。     

信贷消费下我国消费行为模型的研究

分析了消费行为影响因素以及这些因素的变化，给出了有无信贷两种情况下消费行为模型，并结合我国特点，对信贷消费的市场拉动效应及相应的信用政策进行了研究。认为，消费信贷的刺激，消费总支出增加，消费行为将产生消费的“贷款效应”；在信用政策上应该引导消费文化和消费观念、增加有效供给、稳定的收入和支出预期的信心等。     

改型尾缘对翼型流场影响的数值模拟

建立了NACA23012翼型后缘加装Gurney襟翼模型和高度为2%弦长的Gurney襟翼翼型的后缘表面曲率进行修改的模型,并利用FLUENT软件对其进行数值模拟,得到不同模型在不同风速,不同攻角下的空气动力学性能（Cl、Cd）以及翼型表面压力、速度、马赫数的分布等.计算结果表明：四种单纯的加装Gurney襟翼的模型中,高度为2%弦长的Gurney襟翼模型具有最高的升阻比.而与单纯加装Gurney襟翼的模型相比,修改下表面后缘曲率的模型的升阻比可提高14%左右.在0.5度攻角以下及负攻角时,与 NACA23012原型相比,各改型的升阻比都有所提高.     

Coronal Dynamics and the AIA on SDO

We provide a brief overview of present-day studies of inner corona dynamics, with examples of mass ejections (CME), flares and active region dynamics. While the names of the topics have not changed in several decades, the internal details and the language used to express the nature of the problem have changed considerably. We conclude with a short discussion of the contribution to studies of coronal dynamics to be expected from the Atmospheric Imager Assembly (AIA) on the Solar Dynamics Observatory.     

Impact of Solar Activity on Stratospheric Ozone and NO2 Observed by Gomos/Envisat

Energetic proton precipitation occurring during solar events can increase the production of odd nitrogen in the upper stratosphere and mesosphere. A very intense solar proton event (SPE) occurred on 28 October 2003. Its impact on the composition of the middle atmosphere was observed in details due to the availability of several space instruments. Here we present GOMOS observations of a strong NO₂increase and a related ozone decrease in the upper stratosphere at north polar latitude. The perturbation of the chemical composition of the stratosphere was observed until the middle of December 2003. A strong NO₂ increase was also observed in the south polar vortex in June-July 2003. It is tentatively attributed to the effect of an SPE with protons of moderate energy occurring on 29 May 2003. If this hypothesis is confirmed, it will imply that the global effect of SPEs on the composition of the stratosphere is underestimated when only strong energy SPEs are considered.     

太阳活动区R9077引起的强烈吸收事件

利用南极中山站的观测数据分析了太阳活动区R9077所引起的强烈吸收事件，其中2000年7月14日的太阳质子事件引起了持续3天多强烈的极盖吸收，同时，激烈的太阳活动使磁层处于极度扰动状态，磁层高能粒子沉降使许多持续时间较短的吸收峰叠加在极盖吸收背景之上，最突出的是7月1日的吸收增强事件，其最大值达26dB。这是自1997年2月中山站安装成像式宇宙噪声接收机以来观测到的最强的吸收，另一个较突出的吸收峰发生在14日1753UT前后，本文还讨论了产生这些吸收的原由。     

What is the optimum solar proxy for long-term ionospheric investigations?

The problem of optimum solar proxy is important for long-term and/or climatological studies of ionospheric parameters. Here we focus on possibly different optimum solar proxies for different ionospheric parameters, as they are affected by partly different spectral ranges of solar ionizing radiation. We use yearly average values of foF2 and foE of four European stations with long (1976–2014) and high-quality data (Juliusruh, Pruhonice, Rome, Slough/Chilton), and the global total electron content (G-TEC). Four solar proxies are used: F10.7, Mg II, solar Lymna-alpha flux Fα and sunspot numbers. The most important finding is that the optimum solar proxies are different for different ionospheric parameters. The most suitable solar proxy for foF2 is found to be Mg II, whereas for foE F10.7 evidently outperforms Mg II. Fα and sunspot numbers perform slightly worse but none of four solar proxies performs poorly. F10.7 is favored for G-TEC, to some extent surprisingly, as previous results favored rather Mg II.     

Wave propagation analysis for a second strain gradient rod theory

In this work, an enriched model describing the longitudinal wave propagation is established based on Mindlin’s Second Strain Gradient (SSG) theory, which can describe the heterogeneity caused by the micro-structure interactions in the frame of continuum mechanics. The governing equation and associated boundary conditions are derived based on Hamilton's principle, then the dispersion relation of non-classical longitudinal wave together with the extra-waves appearing exclusively in SSG theory model are investigated. The investigations are based on the modal density, energy flow, and forced response of the rod. Wave transmission and reflection through planar interfaces based on the proposed model have been calculated. Finally, the results of the enriched model are well interpreted by comparing with the classical theory results, and some useful conclusions are derived on the SSG theory based model in the wave propagation characterization.     

The interconnection and phase asynchrony between the geomagnetic indices’ periodicities: A study based on the interplanetary magnetic field polarities 1967–2018 utilizing a cross wavelet analysis

In this article, we investigate the interconnection and phase asynchrony between the periodicities of geomagnetic activity indices Kp, Ap, aa, and Dst according to the interplanetary magnetic field (IMF) polarities, toward (T) or away (A), during the time interval 1967–2018. For this purpose, the daily data of Kp, Ap, aa, and Dst indices during the considered period have been sorted into two groups (T and A) according to the IMF polarities. The wavelet transform (WT), the cross-wavelet transform (XWT), and the wavelet coherence (WTC) have been applied on the monthly averages of T and A groups for each geomagnetic index. Moreover, the correlation analyses (linear and running correlations) between the annual averages of T and A groups of each geomagnetic index have been investigated. The results of XWT and WTC revealed the existence of a long-term periodicity in the frequency range 8–16 yr for the monthly averages of T and A groups for aa, Kp, and Ap indices existed during the entire period. In contrast, the Dst index revealed this periodicity during the period 1980–2018. In addition, during this frequency band, both T and A groups of each geomagnetic index revealed a highly positive correlation and nearly in-phase relationship behavior. Furthermore, during the frequency band 4–8 yr, the XWT displayed a prominent periodicity that occurred for the monthly averages of T and A groups of each geomagnetic index, revealing a phase change during some time intervals. Periodicity in the range 2–4 yr for the monthly averages of T and A groups of aa, Kp_, Ap, and Dst occurred in the intervals; 1967–2009 for aa and Kp, 1967–2007 for Ap, and 1976–1995 for Dst. The annual periodicity is also identified for all considered indices. Both T and A groups of Dst shared a semiannual periodicity (~187 days) during different intervals in the entire period. On the other hand, a periodicity around 0.25-yr (~90 days) appeared only near the times of solar activity maxima in the case of the T and A groups of aa, Kp, and Ap indices.