Acknowledgments

My heartfelt thanks to my parents for all the support they gave me throughout the year, and words of courage and motivation. My sister who was always available to help and support me, and with her help everything was easier. Still to my brother in law who always showed interest in the project I was undertaking. To my girlfriend for all the support shown and for always being with me in the most difficult moments. To my faculty colleagues and friends especially to Carlos Barata, Tiago Aparı́cio, Fábio Santos, Gonçalo Semedo, Claudio Saramagaio and Rita Henriques for their support, companionship and all the help they were always available to give me. To João Martins and Oliver Schnell my project partners, for the help which existed between all of us, and the group spirit created from the day one. I also want to thank the teachers Luis Carriço, Carlos Duarte and my co-supervisor Francisco M. Couto by all the ideas suggested during project creation. A special thanks to my advisor Tiago Guerreiro throughout his support and for guiding me throughout this year and in the development of the project. iii I dedicate this thesis to all those who supported me throughout my lif