In this paper we present an efficient approach for the prediction of two sunspot-related time series, namely the Yearly Sunspot Number and the IR5 Index, that are commonly used for monitoring solar activity. The method is based on exploiting partially recurrent Elman networks and it can be divided into three main steps: the first one consists in a “de-rectification” of the time series under stu...

0.75 Â passband and one of the chromosphere and prominences taken at the same wavelength with a 3 Â passband. This system permits study of the relationship between prominences and disk features. On April 30, 1960, while the instrument was still being adjusted, a sequence of pictures showing a fine set of loops over a large sunspot was obtained (Plate I). One end of the loops is seen clearly to ...

We study a standard two period economy with one nominal bond and one …rm. The input of the …rm is done in the …rst period and …nanced with the nominal bond, and its pro…ts are distributed to the shareholders in the second period. We show that a sunspot equilibrium exists around each e¢ cient equilibrium. The interest rate is lower than optimal and there is over production in sunspot equilibria,...

Both auroral and geomagnetic activity provide information from which the behavior of the magnetosphere and the solar wind can be inferred. Swedish auroral sightings during the eighteenth and nineteenth centuries show a remarkable pattern of changes in the latitudes at which the auroras were observed. Auroral reports from New England confirm that these variations were hemisphere-wide. The patter...

The process of sunspot formation is considered with the account of heat effects. According to the Le Chatelier principle, a local overheating must precede to the cooling of solar surface in the places of sunspot formation. The sunspot dynamics is a process close to the surface nucleate-free boiling in a thin layer with formation of bubbles (or craters), so we focus on the analogy between these ...

A multi-agent system is developed here to predict monthly details of the upcoming peak of the 24 solar magnetic cycle. While studies typically predict the timing and magnitude of cycle peaks using annual data, this one utilizes the unsmoothed monthly sunspot number instead. Monthly numbers display more pronounced fluctuations during periods of strong solar magnetic activity than the annual suns...