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Solar time series analysis is one of the most important topics in statistical astrophysics, which aims at revealing the complex dynamical behavior of long-term solar magnetic activity. In this work, several statistical analysis techniques are combined to study the long-term persistence and phase relationship of monthly filament activity between the low latitudes and the high latitudes during the time period from 1957 April to 2010 June. Based on these advanced analysis approaches, the following remarkable results are found: (1) solar filament activity at the low latitudes lags behind that at the high latitudes with a phase shift of 40 months, and the largest positive coefficient is found to be 0.35; (2) solar filament activity at both the low and the high latitudes exhibits a strong long-term persistence behavior, that is, their nonlinear dynamical behavior could not be regarded as stochastic phenomenon; (3) the relative phase relationships between the low latitudes and the high latitudes are not in phase for the studied periodic scales, but they are coherent in the periods of 10-14 years. To sum up, the analysis results could give more useful information on our understanding the solar and the stellar dynamo theory, and also provide some crucial roles of solar magnetic activity variations.

Solar time series manifests nonlinear and non-stationary behaviors, and perhaps multi-modal dynamical processes operating in solar magnetic indicators. In the present work, the novel ensemble empirical mode decomposition (EEMD) is applied to study the monthly distribution of sunspot areas produced by the extended time series of solar activity indices (ESAI) database in the time interval from 1821 January to 1989 December. It is established that the quasi-periodic variations of monthly sunspot areas consist of at least three well-defined dynamical components: one is the short-term variations which are obviously smaller than one year, the second one is the mid-term variations with periodic scales varying from 1 year to 15 years, and the last component is the periodic variation with periodicities larger than 15 years. The analysis results indicate the EEMD technique is an advanced tool for analyzing the weakly nonlinear and non-stationary dynamical behaviors of solar magnetic activity cycle.

This paper studies the effect of the heterogeneity of major shareholders of listed companies in China on the lossreversibility after they occur loss.The empirical results show that in the sample of all the losses listed companies,the extent of loss reversal occurred of non-controlling shareholders of listed companies after loss wassignificantly higher than the losses listed companies of controlling shareholders, that have dispersed ownershipand validity checks and balances to shareholders of listed companies to make proactive in losses after losses, buteven larger losses reversed, the losses of state-owned controlling shareholders of listed companies and the lossof other listed companies, the largest shareholder of the loss of state property, the largest shareholder of listedcompanies and the loss of other property companies listed on the extent of the loss is not significantly reversed.