This thesis has been funded by the São Paulo Research Foundation, FAPESP -Brazil, under grants 2012/15783-8 and 2014/09894-7, for which I am very grateful. I would like to express my sincere gratitude to the anonymous reviewer(s), who believed in our PhD proposal and provided us with valuable comments on each stage of the development of this research.I would like to thank the University of São Paulo, USP -Brazil, which was my home university during these four and a half years of intense work. I am also grateful to the Catholic University of Leuven, KU Leuven -Belgium, which was my host university during more than one year. In special, I am deeply grateful to both the Housing and Health Service teams at the KU Leuven, for the prompt help in arranging a suitable accommodation for me and my family, as well as for the invaluable help with some health issues that we had to dealt with while our stay in Belgium.My infinitely big thanks goes to my Brazilian promoter, Prof. Leopoldo de Oliveira, for the continuous support of numerous aspects, not only regarding my thesis, but also in my life and even in the life of my family. Words are insufficient to express my gratitude for his knowledge, motivation, encouragement, interest on my work and patience. My special thanks also goes to his wife, Prof a . Maira da Silva, for her knowledge and constant encouragement.My sincere thanks goes to my Belgian promoter, Prof. Wim Desmet, who provided me an opportunity to join his team. Thank you very much, Prof. Wim, for your guidance through the monthly meetings, as well as for the useful discussions during private meetings, for your feedback after some oral presentations and corrections to this manuscript. I remain indebted to Prof. Wim, for his disposal when solving all the administrative issues at the KU Leuven, as well as when I suffered from some health issues, despite his busy schedule. A special thanks goes to Prof. Paul Sas, who allowed me using his DSP module, when running the experimental campaign at the KU Leuven.Besides my promoters, I would like to thank the supervision committee at USP, composed by Prof. Marcelo Areias Trindade and Prof. Carlos de Marqui Jr., as well as to thank the supervision committee at the KU Leuven, composed by Prof. Paul Sas, Prof. Herman Van der Auweraer and Prof. Marc Moonen. All their comments and suggestions have undoubtedly improved the quality of this work. The joint evaluation committee composed by Prof. Paul Sas, Prof. Vicente Lopes Júnior, Prof. Domingos Alves Rade and Prof. Flávio Donizeti Marques, is also gratefully acknowledged for their interest and suggestions on this work.I would like to express my thanks to the staff at Siemens Industry Software NV. (Belgium), for the prompt help in providing us with measurements of the acoustic emission of the powertrain in hybrid electric vehicles. I am especially grateful to Herman Van der Auweraer, Karl Janssens, Mathieu Sarrazin and Giampiero Accardo for their help with the experimental data, as well as for the fruitful discussions on the goals...