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Wavelet analysis of sunspot numbers
Chinese Astronomy and Astrophysics, 1998Abstract The principle of detecting singularities in the signal using wavelet transform is discussed. The yearly mean sunspot numbers during 1700–1993 are analyzed by this technique and the individual periods of sunspot activity are determined, as dinstinct from the tranditional method.
Bo Feng, Xi-zheng Ke, Hua-ling Ding
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Sunspot Number Calculation Using Clustering
2011 Third National Conference on Computer Vision, Pattern Recognition, Image Processing and Graphics, 2011We present a method for automatically detecting the number of sunspots and sunspot groups in standardized images of the Sun. We use adaptive thresholding to isolate the sunspots, and data clustering techniques to classify them into groups. By working on both the MDI Continuum and Magneto gram images, our method groups those sunspots together which ...
Ujjwal Dasgupta +2 more
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The Schwabe and Gleissberg Periods in the Wolf Sunspot Numbers and the Group Sunspot Numbers
Solar Physics, 2005Three wavelet functions: the Morlet wavelet, the Paul wavelet, and the DOG wavelet have been respectively performed on both the monthly Wolf sunspot numbers (R-z) from January 1749 to May 2004 and the monthly group sunspot numbers (R-g) from June 1795 to December 1995 to study the evolution of the Gleissberg and Schwabe periods of solar activity.
K. J. Li, P. X. Gao, T. W. Su
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Rome rainfall and sunspot numbers
Journal of Atmospheric and Terrestrial Physics, 1993Abstract The accumulated departure from mean (ADM) of the 208 yr Rome rainfall strongly inversely resembles the ADM of sunspot numbers. The ADM for the Bay of Biscay sea surface temperature also strongly resembles sunspot numbers and Rome rainfall. These data suggest that long-term increasing solar radiation warms parts of the North Atlantic Ocean ...
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Final relative sunspot‐numbers 1932
Terrestrial Magnetism and Atmospheric Electricity, 1933The following Tables contain the final relative sunspot‐numbers for 1932, for the whole disc of the Sun, based on observations made at the Zurich Observatory, supplemented by series furnished by other cooperating observatories for days (indicated by asterisks) where no observations were possible at Zurich.Table 1 gives the yearly means of the relative ...
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Sunspot numbers can detect pandemic influenza A: The use of different sunspot numbers
Medical Hypotheses, 2007J.M. Vaquero, M.C. Gallego
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The unusual minimum of sunspot cycle 23 caused by meridional plasma flow variations
Nature, 2011Dibyendu Nandy +2 more
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