Ibon Ruiz Oleagordia

New approach for oesophageal speech enhancement

This paper presents an oesophageal speech enhancement algorithm. Such an exceptionally special type of voice is due to the laryngectomy undergone by those persons with larynx cancer. An oesophageal voice has extremely low intelligibility. This work proposes a method to improve its quality, which consists of stabilizing the transfer function poles of the vocal tract model so as to improve a signals formants. With this aim, the joint use of three techniques has been applied: firstly, Digital Wavelet Transform technique, secondly, Kaiman filtering technique and thirdly, an algorithm that transforms the modulus and phase of vocal tracts poles. When using this efficient speech enhancement Kaiman Filtering procedure, the speech signal is usually modelled as an autoregressive (AR) process and represented in the state-space domain. The final speech improvement has been measured with the help of Multi-Dimensional Voice Program (MDVP) tools.

Accessible schematics content descriptors using image processing techniques for blind students learning

The documentation used when teaching Electronics in Engineering Degrees is not accessible to blind or visually disabled students because they can just have a text to speech conversion of the paragraphs but not a circuits schematics to speech conversion. This work presents an open source algorithm integrated in a tool compatible with Open Office. This algorithm applies digital image processing and computer vision techniques to any schematic circuits included in the document. It provides an intelligent and automatic textual description of both the sequence of electronic components and the position in the general schematics in order to make it accessible to blind people. Lecturers and teachers will be able to create teaching materials with common applications such as PSpice or Oregano, and then they will convert the charts into accessible-content figures in a very easy way. The screen reader will let them navigate around the graph in order to access the information of a concrete element in it. Assessment has been done with real trials and a satisfaction survey.

Enhancing Communication Theory Learning in the European Higher Education Area

This article describes a new methodology adapted to the Bologna process within the sphere of teaching modulations. For this purpose, a new educational tool in the area of digital signal processing for communication theory has been developed for undergraduates in engineering. On the one hand, the application is intended to serve as a system for collaborative learning with which the student can carry out a mathematical and graphical study of all kinds of traditional communications systems functions, such as basic mathematical operations, modulations and filters in Octave/Matlab, by using examples provided by the application. On the other hand, the students will be able to develop new plug-ins with new problems and systems simulated in Octave/Matlab. The evaluation of the tool was based on a series of tests monitoring the students and contrasting academic results from 2006. The results showed an increase in the number of students passing the subject.