Numerical estimation of Carbonate properties using a digital rock physics workflow

Digital rock physics combines modern imaging with advanced numerical simulations to analyze the physical properties of rocks -- In this paper we suggest a special segmentation procedure which is applied to a carbonate rock from Switzerland -- Starting point is a CTscan of a specimen of Hauptmuschelkalk -- The first step applied to the raw image data is a nonlocal mean filter -- We then apply different thresholds to identify pores and solid phases -- Because we are aware of a nonneglectable amount of unresolved microporosity we also define intermediate phases -- Based on this segmentation determine porositydependent values for the pwave velocity and for the permeability -- The porosity measured in the laboratory is then used to compare our numerical data with experimental data -- We observe a good agreement -- Future work includes an analytic validation to the numerical results of the pwave velocity upper bound, employing different filters for the image segmentation and using data with higher resolution

Uso del Análisis Digital de Imágenes (ADI) como herramienta para el estudio petrográfico en rocas metamórficas

Los retos en las actividades de innovación en docencia, se basan en la necesidad de proponer nuevos métodos y estrategias que permitan ampliar y armonizar toda clase de recursos que se tengan disponibles, para potencializar los resultados en el proceso de enseñanza - aprendizaje -- En el caso de la asignatura de rocas metamórficas, es muy común identificar dificultades en los estudiantes en el análisis petrográfico, identificación de minerales, patrones texturales, y relación con curvas de blastesis; por lo anterior se quiso implementar el tratamiento de análisis digital de imágenes (ADI), como una herramienta pedagógica que facilite el aprendizaje de los mismos

A simple but efficient voice activity detection algorithm through Hilbert transform and dynamic threshold for speech pathologies

A simple but efficient voice activity detector based on the Hilbert transform and a dynamic threshold is presented to be used on the pre-processing of audio signals -- The algorithm to define the dynamic threshold is a modification of a convex combination found in literature -- This scheme allows the detection of prosodic and silence segments on a speech in presence of non-ideal conditions like a spectral overlapped noise -- The present work shows preliminary results over a database built with some political speech -- The tests were performed adding artificial noise to natural noises over the audio signals, and some algorithms are compared -- Results will be extrapolated to the field of adaptive filtering on monophonic signals and the analysis of speech pathologies on futures works