Showing papers on "Gnome published in 2008"

Guided non-linear model estimation (gnoME).

Abstract: The present work describes a new method for modeling 3-D motion capture data of speech movements. 27 markers on the face of a speaker uttering 27 VCVs were tracked by a Vicon motion capture system. The 3-D coordinates of the markers in all frames of the recording were modeled in four ways: 1) a plain PCA, 2) a guided PCA where each component is determined on a subset of markers that represent an articulator and the component is used to reconstruct the data by linear regression, 3) a cubic model where the components are determined by a PCA and the components are used to reconstruct the data by a polynomial of third order, and 4) a guided cubic model where each component is determined by a PCA on a subset of markers and the components are used to reconstruct the data by a polynomial of third order. Results show that the latter method – called guided non-linear model estimation (gnoME) with cubic regression leads to meaningful articulatory parameters like the guided PCA while the variance explanation equals that one of the plain PCA and the accuracy of the 3-D data reconstruction is higher compared to the plain PCA.

An Algebraic Semantics for Gnome via a Translation to étoile Specifications

Abstract: Gnome is a simplified and revised version of the object oriented specification language Oblog. A formal semantics based on temporal logic has already been defined, and alternative semantics are also being studied. The goal of this article is to propose an algebraic semantics for Gnome, using etoile. etoile is an algebraic theory for the specification of systems, with an object oriented specification style. It allows to specify objects with local states, systems and their invariants. There is also in etoile a logical system which is sound w.r.t. the algebraic semantics. Given a Gnome specification, we obtain an algebraic semantics for it by translating the Gnome specification into an etoile specification. The main difficulties come from the fact that Gnome is a concrete specification language with built-in primitives whilst etoile is only a specification theory, and also from the way methods are called and executed in Gnome. Proofs can be performed from a Gnome specification using the etoile calculus.