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11.
Gui-Qing Zhang 《地震学报(英文版)》1998,11(4):495-500
The relations between sunspot numbers and earthquakes (M≧6), solar 10.7 cm radio flux and earthquakes, solar proton events and earthquakes have been analyzed in this paper. It has
been found that: (1) Earthquakes occur frequently around the minimum years of solar activity. Generally, the earthquake activities
are relatively less during the peak value years of solar activity, some say, around the period when magnetic polarity in the
solar polar regions is reversed. (2) the earthquake frequency in the minimum period of solar activity is closely related to
the maximum annual means of sunspot numbers, the maximum annual means of solar 10.7 cm radio flux and solar proton events
of a whole solar cycle, and the relation between earthquake and solar proton events is closer than others. (3) As judged by
above interrelationship, the period from 1995 to 1997 will be the years while earthquake activities are frequent. In the paper,
the simple physical discussion has been carried out.
These results supported the exploration and studies of some researchers to a certain extent.
This work is supported by Foundation of the Chinese Academy of Sciences (major item). 相似文献
12.
在柱坐标下将黑子周围的环形区域(黑子除外)内的振荡分解为朝向黑子传播的(入射的)波和离开黑子传播的(出射的)波。对无黑子的环形区域内的振荡也进行了同样的分解。将黑子周围的入射波看成是被黑子磁流管磁化了的介质(介质内的磁场基本是水平的)中的波。而无黑子区的入射波看成是非磁化介质中的波。比较这两种波在固定波数下功率随频率的分布发现,在磁化介质中不同径向除n的声波(p模)频率系统降低,同时功率也降低,降低的功率最高达非磁化介质中波的功率的30%。而比较在固定频率下功率随波数的分布发现,磁场中f模及n=1,2,3的p模的脊向高波数方向位移,功率的降低受频率调制,即声波在某些有限的频带中被吸收。这些观测表明,在磁场中p模与磁声重力波(MAG)产生了模式混合或耦合。模式混合的存在支持了模式转换作为p模式被黑子吸收的机制的解释。此外,本文还分析了转换的MAG波进入黑子磁流管(其中的磁场基本上是垂直的)后进一步被吸收,吸收的功率最高达MAG波的20%。在磁流管内没有进一步观测到模式的转换 相似文献
13.
《New Astronomy》2015
Analysis of long-term solar data from different observatories is required to compare and confirm the various level of solar activity in depth. In this paper, we study the north–south asymmetry of monthly mean sunspot area distribution during the cycle-23 and rising phase of cycle-24 using the data from Kodaikanal Observatory (KO), Michelson Doppler Imager (MDI) and Solar Optical Observing Network (SOON). Our analysis confirmed the double peak behavior of solar cycle-23 and the dominance of southern hemisphere in all the sunspot area data obtained from three different resources. The analysis also showed that there is a 5–6 months time delay in the activity levels of two hemispheres. Furthermore, the wavelet analysis carried on the same data sets showed several known periodicities (e.g., 170–180 days, 2.1 year) in the north–south difference of sunspot area data. The temporal occurrence of these periods is also the same in all the three data sets. These results could help in understanding the underlying mechanism of north–south asymmetry of solar activity. 相似文献
14.
本文把我们在文[1]和[2]中建立的诊断方法,应用于美国高山天文台斯托克斯参量仪对1978年12月11日太阳黑子本影和半影取得的Q和U两个参数的轮廓,发现这个黑子的磁力线不呈现较强的扭绞。 相似文献
15.
G. A. Krasinsky 《Celestial Mechanics and Dynamical Astronomy》2006,96(3-4):169-217
Improved differential equations of the rotation of the deformable Earth with the two-layer fluid core are developed. The equations describe both the precession-nutational motion and the axial rotation (i.e. variations of the Universal Time UT). Poincaré’s method of modeling the dynamical effects of the fluid core, and Sasao’s approach for calculating the tidal interaction between the core and mantle in terms of the dynamical Love number are generalized for the case of the two-layer fluid core. Some important perturbations ignored in the currently adopted theory of the Earth’s rotation are considered. In particular, these are the perturbing torques induced by redistribution of the density within the Earth due to the tidal deformations of the Earth and its core (including the effects of the dissipative cross interaction of the lunar tides with the Sun and the solar tides with the Moon). Perturbations of this kind could not be accounted for in the adopted Nutation IAU 2000, in which the tidal variations of the moments of inertia of the mantle and core are the only body tide effects taken into consideration. The equations explicitly depend on the three tidal phase lags δ, δ
c, δ
i responsible for dissipation of energy in the Earth as a whole, and in its external and inner cores, respectively. Apart from the tidal effects, the differential equations account for the non-tidal interaction between the mantle and external core near their boundary. The equations are presented in a simple close form suitable for numerical integration. Such integration has been carried out with subsequent fitting the constructed numerical theory to the VLBI-based Celestial Pole positions and variations of UT for the time span 1984–2005. Details of the fitting are given in the second part of this work presented as a separate paper (Krasinsky and Vasilyev 2006) hereafter referred to as Paper 2. The resulting Weighted Root Mean Square (WRMS) errors of the residuals dθ, sin θd for the angles of nutation θ and precession are 0.136 mas and 0.129 mas, respectively. They are significantly less than the corresponding values 0.172 and 0.165 mas for IAU 2000 theory. The WRMS error of the UT residuals is 18 ms. 相似文献
16.
主要介绍利用Microsoft Visual Basic.NET编写的地形图分幅编号查询与面积计算程序。通过该程序,根据经纬度坐标或高斯坐标,可查询该点所在各种基本比例尺下的图幅编号、西南图廓点的经纬度坐标以及在不同坐标系下的图幅面积。 相似文献
17.
H. Kiliç 《Solar physics》2009,255(1):155-162
The short-term periodicities in sunspot numbers, sunspot areas, and flare index data are investigated in detail using the
Date Compensated Discrete Fourier Transform (DCDFT) for the full disk of the Sun separately over the rising, the maximum,
and the declining portions of solar cycle 23 (1996 – 2006). While sunspot numbers and areas show several significant periodicities
in a wide range between 23.1 and 36.4 days, the flare index data do not exhibit any significant periodicity. The earlier conclusion
of Pap, Tobiska, and Bouwer (1990, Solar Phys.
129, 165) and Kane (2003, J. Atmos. Solar-Terr. Phys.
65, 1169), that the 27-day periodicity is more pronounced in the declining portion of a solar cycle than in the rising and maximum
ones, seems to be true for sunspot numbers and sunspot area data analyzed here during solar cycle 23. 相似文献
18.
《Marine Policy》2014
Tracking the financial well-being of vessels that depend on a marine fishery resource is an important function of regulators. This research demonstrates how simple indices can be constructed and utilized to track the economic well-being of vessels operating in the Northeast (USA) Multispecies (Groundfish) Fishery. The indices, which use both public and private data, can separately track trends in inputs, outputs, and prices. For the Northeast Multispecies Fishery, the indices reveal that the economic well-being of the groundfish fleet has improved under catch share management through gains in productivity. 相似文献
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