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A book template in Greek

Modelo de monografia criado para a Faculdade de Computação da Universidade Federal do Pará a partir da classe abntex2.

TIPE 2016–2017 La génération algorithmique de nombres aléatoires : Utilisation à des fins de simulation

Author: John Liaperdos (ioannis.liaperdos@gmail.com) Edited by: Jordi Jaromil Cruz-Medrano(jordi.cruz@uppuebla.edu.mx)

Primeira versão de um template de dissertação/tese de mestrado/doutorado para UNIFEI. Modelo baseado no trabalho de Lauro César Araújo, disponível em : http://www.abntex.net.br/

Case report poster

Slide template for presentations at the Otto von Guericke University in Magdeburg based on the beamer document class in a 16:9 format

Folienvorlage für Präsentationen an der Otto-von-Guericke-Universität in Magdeburg auf Basis der beamer-Dokumentklasse im 16:9-Format

There are several voice communication systems that are used nowadays which are capable of maintain voice calls between two users in real time. Telephones are widely used all around the world in an unlimited kind of situations. All of these situations expose the microphone (or microphones) of the phones to different and unpredictable noises, as street noise, sea noise, rain noise, wind noise, unwanted voices, car motors, etc. As microphones capture all the sounds around it, including the wanted voice and the unwanted noises, it is necessary to implement digital real time filters capable of attenuate as much as possible all the surrounding noises. It exists a large quantity of noise reduction methods that have been used in the calling algorithms of phones. Even if these methods have had, in general, a good performance, there is still a research being done in this area in order to improve the current results. Because of this, the multichannel methods were created (using multiple microphones) as well as new algorithms that pretend to have a better noise reduction than the single channel methods. Most of these methods require a speech presence probability (SPP) method to achieve the noise reduction. The following document presents a research about different SPP methods as well as a comparison between these. This includes an explanation on how theses algorithm work, a Matlab implementation using real voice and noise recordings and objective tests of the filter.