Julian Arias - Academia.edu (original) (raw)
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Papers by Julian Arias
Automatic hypernasality detection in children with Cleft Lip and Palate is made considering five ... more Automatic hypernasality detection in children with Cleft Lip and Palate is made considering five Spanish vowels. Characterization is performed by means of some acoustic and noise features, building a representation space with high dimensionality. Most relevant features are selected using Principal Components Analisis and linear correlation in order to enable clinical interpretation of results and achieving spaces with lower dimensions per vowel. Using a Linear-Bayes classifier, success rates between 80% and 90% are reached, beating success rates achived in similiar studies recently reported.
Se presenta una metodología de diseño simultáneo de una etapa de extracción de características y ... more Se presenta una metodología de diseño simultáneo de una etapa de extracción de características y un clasificador basado en modelos ocultos de Markov (HMM), por medio del algoritmo de mínimo error de clasificación (MCE). La extracción de características ...
IEEE Transactions on Biomedical Engineering, 2008
In this work an entropy based nonlinear analysis of pathological voices is presented. The complex... more In this work an entropy based nonlinear analysis of pathological voices is presented. The complexity analysis is carried out by means of six different entropies, including three measures derived from the entropy rate of Markov chains. The aim is to characterize the divergence of the trajectories and theirs directions into the state space of Markov chains. By employing these measures in conjunction with conventional entropy features, it is possible to improve the discrimination capabilities of the nonlinear analysis in the automatic detection of pathological voices.
Biomedical Signal Processing and Control
Pattern Recognition, 2010
IEEE Transactions on Biomedical Engineering, 2011
This paper proposes a new approach to improve the amount of information extracted from the speech... more This paper proposes a new approach to improve the amount of information extracted from the speech aiming to increase the accuracy of a system developed for the automatic detection of pathological voices. The paper addresses the discrimination capabilities of 11 features extracted using nonlinear analysis of time series. Two of these features are based on conventional nonlinear statistics (largest Lyapunov exponent and correlation dimension), two are based on recurrence and fractal-scaling analysis, and the remaining are based on different estimations of the entropy. Moreover, this paper uses a strategy based on combining classifiers for fusing the nonlinear analysis with the information provided by classic parameterization approaches found in the literature (noise parameters and mel-frequency cepstral coefficients). The classification was carried out in two steps using, first, a generative and, later, a discriminative approach. Combining both classifiers, the best accuracy obtained is 98.23% ± 0.001.
Automatic hypernasality detection in children with Cleft Lip and Palate is made considering five ... more Automatic hypernasality detection in children with Cleft Lip and Palate is made considering five Spanish vowels. Characterization is performed by means of some acoustic and noise features, building a representation space with high dimensionality. Most relevant features are selected using Principal Components Analisis and linear correlation in order to enable clinical interpretation of results and achieving spaces with lower dimensions per vowel. Using a Linear-Bayes classifier, success rates between 80% and 90% are reached, beating success rates achived in similiar studies recently reported.
Se presenta una metodología de diseño simultáneo de una etapa de extracción de características y ... more Se presenta una metodología de diseño simultáneo de una etapa de extracción de características y un clasificador basado en modelos ocultos de Markov (HMM), por medio del algoritmo de mínimo error de clasificación (MCE). La extracción de características ...
IEEE Transactions on Biomedical Engineering, 2008
In this work an entropy based nonlinear analysis of pathological voices is presented. The complex... more In this work an entropy based nonlinear analysis of pathological voices is presented. The complexity analysis is carried out by means of six different entropies, including three measures derived from the entropy rate of Markov chains. The aim is to characterize the divergence of the trajectories and theirs directions into the state space of Markov chains. By employing these measures in conjunction with conventional entropy features, it is possible to improve the discrimination capabilities of the nonlinear analysis in the automatic detection of pathological voices.
Biomedical Signal Processing and Control
Pattern Recognition, 2010
IEEE Transactions on Biomedical Engineering, 2011
This paper proposes a new approach to improve the amount of information extracted from the speech... more This paper proposes a new approach to improve the amount of information extracted from the speech aiming to increase the accuracy of a system developed for the automatic detection of pathological voices. The paper addresses the discrimination capabilities of 11 features extracted using nonlinear analysis of time series. Two of these features are based on conventional nonlinear statistics (largest Lyapunov exponent and correlation dimension), two are based on recurrence and fractal-scaling analysis, and the remaining are based on different estimations of the entropy. Moreover, this paper uses a strategy based on combining classifiers for fusing the nonlinear analysis with the information provided by classic parameterization approaches found in the literature (noise parameters and mel-frequency cepstral coefficients). The classification was carried out in two steps using, first, a generative and, later, a discriminative approach. Combining both classifiers, the best accuracy obtained is 98.23% ± 0.001.