José A. Vallejo

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We describe an averaging procedure on a Dirac manifold, with respect to a class of compatible actions of a compact Lie group. Some averaging theorems on the existence of invariant realizations of Poisson structures around (singular) symplectic leaves are derived. We show that the construction of coupling Dirac structures (invariant with respect to locally(More)
ln this paper we present an strategy to improve the naturalness of a text to speech system for Spanish based on the development of a new pitch generator. The new model worKs with text previously parsed with an heuristic breath group parser. The results show that the new pitch generator is pre'ferred by listeners compared to our previous model. lt is also(More)
Accurate prediction of segmental duration from text in a textto-speech system is difficult for several reasons. One specially relevant is the great quantity of contextual factors that affect timing and how to model them. There are many parameters that affect duration, but not all of them are always relevant. We present a complete environment in which to(More)
In this paper, we describe the development of a female voice in a Restricted-Domain Speech Synthesis System for Spanish. For the design of the database, we have used a greedyalgorithm approach that focus not only on covering a set of target phonemes, but also on mimicking the histogram of prosodic features from a larger database. For modeling the prosody,(More)
Accurate prediction of segmental duration from text in a text-to-speech system is difficult for several reasons. One which is especially relevant is the great quantity of contextual factors that affect timing and it is difficult to find the right way to model them. There are many parameters that affect duration, but not all of them are always relevant and(More)
Several methods to improve multiple distant microphone (MDM) speaker diarization based on Time Delay of Arrival (TDOA) features are evaluated in this paper. All of them avoid the use of a single reference channel to calculate the TDOA values and, based on different criteria, select among all possible pairs of microphones a set of pairs that will be used to(More)
We present a multi-speaker formant synthesizer based on parameter concatenation. The user can choose among three speakers, two males and one female. The synthesizer stores all the parameters for the basic speaker and linear transformation functions to synthesized the other two. The complete database for one speaker consists of 455 parameterized units(More)
Traditionally, the discussion about the geometrical interpretation of inertial forces is reserved for General Relativity handbooks. In these notes an analysis of the effect of such forces in a classical (newtonian) context is made, as well as a study of the relation between the precession of the Foucault pendulum and the holonomy on a surface, including(More)