Miguel Ángel Carbonero Martín

The Stratonovich–Weyl correspondence for one‐dimensional kinematical groups

The Stratonovich–Weyl correspondence is a restatement of the Moyal quantization where the phase space is a manifold and where a group of transformations acts on it transitively. The first and most important step is to define a mapping from the manifold into the set of self‐adjoint operators on a Hilbert space, under suitable conditions. This mapping is called a Stratonovich–Weyl kernel. The construction of this mapping is discussed on coadjoint orbits of the one‐dimensional Galilei, Poincare, and Newton–Hooke groups as well as the two‐dimensional Euclidean group.

diSNei: A Collaborative Environment for Medical Images Analysis and Visualization

In this paper we describe our environment diSNei, a graphical tool for collaborative image analysis and visualization of models created out of slices of volume data; this application allows a number of users to simultaneous and coordinatedly analyze medical images, create graphical models, navigate through them and superimpose raw data onto the models. The application is intended to help physicians interpret data in the case that ambiguous situations may appear, by means of collaboration with other colleagues. It is therefore an integrated environment for expertise interchange among physicians and we believe that it is a powerful tool for academic purposes as well. Other outstanding application features are its being multiplatform, and, particularly, the fact that it can run on NT computers, and the support for stereo rendering so as to obtain a deep sensation of inmersion into the models.

A topology-based filling algorithm

Abstract In this paper we present a fast-recursive fully automated topology-based algorithm for filling in the interiors of objects that appear in a binary image. The algorithm is based on two topological properties of the image contours: perimeter coincidence and interiority. Based on these parameters the algorithm performs a tree-structured region classification. The final filling is done according to the labels of the tree leaves. The algorithm is well suited to cases in which contours overlap and ambiguities may arise about which regions to fill. The algorithm has been tested with three-dimensional solid objects given by surface representations, both for simple man-made CAD objects and for complicated images taken from human computer tomographies. A table shows the execution times taken by the algorithm for several medical volume data sets.

Central extensions and realizations of one-dimensional Galilean systems and quantization

The unitary irreducible realizations (representations up to a factor) of the maximal non-trivial central extension of the (1 + 1) Galilei group, (1 + 1), are obtained via the linear unitary irreducible representations of its maximal non-trivial central extension, (1 + 1). As an application we construct the Stratonovich - Weyl correspondence, which allows Moyal quantization of classical systems, for two cases of great physical interest: a system in a external variable force field and a variable-mass system.

Multiresolution compression schemes for medical image and volume data

In this paper we propose a multiresolution compression scheme applied to image and volume data. It is intended for rapid browsing in graphical files, in which some regions of interest may exist; therefore the compression algorithms focus on incorporating quick full-reconstruction procedures, both in images and volumes. This scheme is based on vector quantization of the coefficients of a wavelet decomposition. The differences in the methods lie on how vectors in the multiresolution decompositions are selected for vector quantization. We have also developed a client-server application using this scheme, which allows images with increasing levels of detail to be represented in the client system as they are received from the server and decoded. Numerical results show the performances of all the selections made.

Metacognitive Precursors: An Analysis in Children with Different Disabilities.

The analysis of Metacognitive skills is a key element to guide the learning process. Current research has shown the initiation of these skills from an early age. The present study had two aims: (1) to validate a Scale Measuring Precursor Metacognitive Skills (SMPMS) in children with diverse disabilities, and (2) to study possible significant different between different disabilities in precursor metacognitive skill use. We worked with 87 children with different disabilities, with an average age range of 24–37 months. The results have shown high indicators of reliability and validity of the SMPMS. We isolated two factors related to cognitive and metacognitive and self-regulation skills response to an adult. We also found significant differences in the acquisition of metacognitive and self-regulation skills among children with global developmental retardation as compared to children with expressive language and comprehension disability.