77 research outputs found
Wind speed forecasting at different time scales: a non parametric approach
The prediction of wind speed is one of the most important aspects when
dealing with renewable energy. In this paper we show a new nonparametric model,
based on semi-Markov chains, to predict wind speed. Particularly we use an
indexed semi-Markov model, that reproduces accurately the statistical behavior
of wind speed, to forecast wind speed one step ahead for different time scales
and for very long time horizon maintaining the goodness of prediction. In order
to check the main features of the model we show, as indicator of goodness, the
root mean square error between real data and predicted ones and we compare our
forecasting results with those of a persistence model
Search for an infrared counterpart of IGR J16358-4756
We report here on near infrared observations of the field around IGR
J16358-4756. The source belongs to the new class of highly absorbed X-ray
binaries discovered by IBIS/INTEGRAL. Our primary goal was to identify the
infrared counterpart of the source, previously suggested to be a LMXB and then
further reclassified as a HMXB. We have made use of Chandra observations of the
source in order to better constrain the number of possible counterparts. Using
the differential photometry technique, in observations spanning a timescale of
1 month, we found no long term variability in our observations. This is
compatible, and we suggest here, that the source is a HMXB.Comment: 5 pages, 2 figures, all styles included; to be published in: "The
Transient Milky Way: a perspective for MIRAX", eds. F. D'Amico, J. Braga, and
R. E. Rothschild, AIP Conference Proceeding
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