\chapter{Acknowledgements}
\label{ch:ack}

Upon the completion of my thesis, I would like to express my deep gratitude to my research supervisors for their patient guidance, enthusiastic encouragement and useful critiques of this research work.
Besides my advisors, I would like to thank the reporters as well as the rest of the jury for their invaluable contribution.

\kat{the jury and the reporters do not contribute; thank them for their feedback, comments and time}

A special thanks to my department’s faculty, staff and fellow researchers for their valuable assistance whenever needed and for creating a pleasant and creative environment during my studies.

Last but not least, I wish to thank my family and friends for their unconditional support and encouragement all these years.

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\noindent
Cergy-Pontoise, \thedate
