Marta Peracaula

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Previous works on breast tissue identification and abnormalities detection notice that the feature extraction process is affected if the region processed is not well focused. Thereby, it is important to split the mammogram into interesting regions to achieve optimal breast parenchyma measurements, breast registration or to put into focus a technique when we(More)
The Canadian Galactic Plane Survey (CGPS) is a project to combine radio, millimetre and infrared surveys of the Galactic Plane to provide arc-minute scale images of all major components of the interstellar medium over a large portion of the Galactic disk. We describe in detail the observations for the low-frequency component of the CGPS, the radio surveys(More)
Astronomical images provide information about the great variety of celestial objects in the Universe, the physical processes taking place in it, and the formation and evolution of the cosmos. Great efforts are made to automatically detect stellar bodies in images due to the large volumes of data and the fact that the intensity of many sources is at the(More)
Here we discuss two consecutive MERLIN observations of the X-ray binary LS I +61303. The first observation shows a double-sided jet extending up to about 200 AU on both sides of a central source. The jet shows a bent S-shaped structure similar to the one displayed by the well-known precessing jet of SS 433. The precession suggested in the first MERLIN image(More)
In this paper we present a multiresolution-based method for period determination that is able to deal with unevenly sampled data. This method allows us to detect superimposed periodic signals with lower signal-to-noise ratios than in classical methods. This multiresolution-based method is a generalization of the wavelet-based method for period detection(More)
Multi-Scale image analysis is specially suited to detect objects in deep wide field radio astronomical images obtained through interferometric aperture synthesis techniques. These images are usually complex and show a diversity of objects that can be characterized at different scales. In this context wavelet decomposition can be a tool to detect and(More)
In this paper we present a boosting based approach for automatic detection of micro-calcifications in mammographic images. Our proposal is based on using local features extracted from a bank of filters for obtaining a description of the different micro-calcifications morphology. The approach performs an initial training step in order to automatically learn(More)
The automatic segmentation of extended real structures (such as SNRs, HII regions, bow shocks, etc) in large surveys is a difficult task due to their morphological complexity and their wide variety in scale and surface brightness. With the aim of dealing with these issues we propose in this paper an automatic segmentation method based on applying wavelet(More)
We present Very Long Baseline Interferometry (VLBI) observations of the high mass X-ray binary LS I +61◦303, carried out with the European VLBI Network (EVN). Over the 11 hour observing run, performed ∼10 days after a radio outburst, the radio source showed a constant flux density, which allowed sensitive imaging of the emission distribution. The structure(More)
Context. MGRO J2019+37 is an unidentified extended source of very high energy gamma-rays originally reported by the Milagro Collaboration as the brightest TeV source in the Cygnus region. Its extended emission could be powered by either a single or several sources. The GeV pulsar AGL J2020.5+3653, discovered by AGILE and associated with PSR J2021+3651,(More)