I once heard the saying "God does not give us heavier loads than we can bear" and now I understand what it really means. Usually, behind every personal achievement, there are always dozens of people who helped in some way to get it. This part, which I consider one of the most important of the work, is dedicated to all those people who made possible not only the conclusion of this master thesis, but also made my life easier and more bearable at this incredible stage and in this wonderful country, Brazil. First of all, I would like to say thanks to Professor Bruno Adorno for accepting me as his student. From the first moment, he was patient and understanding with my Portuñol and provided me with excellent infrastructure conditions to study and work. I always wondered how he could understand me when I spoke to him quickly and without fluency, but then I learned that he speaks at least three Romance languages, Spanish being one of them. His excellent and precise technical observations guided me and helped me to consolidate my academic training in the best way. Likewise, his notes, corrections and English explanations transformed my archaic and primitive text into a decent and understandable one. One of the best qualities of Professor Bruno is to encourage a student who is going through an existential crisis (which is very common in postgraduate studies), using his unbeatable argumentative ability and humorous sentences, making the student, ironically now with twice tasks to be done, feels better. Finally, I would like to say, that I lost the friendly debate that I had for two years with him, regarding Windows and GNU/Linux. Now I can not imagine my personal computer without a free distribution. I would like to thank the faculty of the engineering school of UFMG for their teachings and explanations on the various topics that helped my academic education. Especially the professors Bruno Adorno, Guilherme Raffo, Leonardo Tôrres and Luis Aguirre, who, with their pedagogy and engineering jokes, kept the class interactive, making them not just masterful, but also agreeable, arousing more and more interest in research in the students. Thanks also to the Brazilian agencies CAPES, CNPQ and FAPEMIG for their financial support during these two years.