Acknowledgments
I would like to thank my supervisor, Prof. Dr. Jo
˜
ao Miranda Lemos and co-supervisor, Prof. Dr. Hor
´
acio
Fernandes, for their inexhaustible patience, wise guidance and time invested during the entire course of
this thesis. I feel extremely lucky to have worked under their supervision.
Many people have been, in one form or another, important in the development of this work. In
particular, Manuel Ribeiro, by helping set up the experimental apparatus, Rui Dias, for his life-saving
soldering skills, Jo
˜
ao Fortunato, for collaborating in the design and production process of the control
board, Prof. Dr. Pedro Sebasti
˜
ao for his help finding the correct way of calculating the error of the
nonlinear least square fit, Prof. Dr. Jo
˜
ao Henriques and Jo
˜
ao Val
´
erio, by sharing their knowledge in the
field of numerical methods in optimal control. I would also like to thank IST, in particular the physics and
electrotechnical engineering departments, IPFN and INESC-ID for their hospitality, material and financial
support.
A kind word goes for all my colleagues and friends who shared the last five years of this unique
challenge, and made the hard work more enjoyable. In particular to Jos
´
e Carvalho, Filipe Richheimer,
Pedro Ribeiro, Eduardo Neto and Rita Tomaz who in several occasions, during the development of this
thesis, have helped with their sharp and honest judgement.
Last, but not the least, I am grateful to my family, for their guidance, advice, and support. A special
word to my parents, Ant
´
onio and Gilda, who made of my education a priority, and contributed more
anyone else for the person I am today.
This thesis has been performed in the framework of projects PTDC/EEI-PRO/0426/2014 and
UID/CEC/50021/2013, funded by the Portuguese Foundation of Science and Technology (FCT).
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