Acknowledgments

At this point I would like to express my gratitude to everyone that helped me in the process of writing this thesis. First, and definitely most important, I want to thank my supervisor, Univ.-Prof. Dr. Alexander Ostermann, for the supervision and tremendous support throughout the development of my thesis and beyond. I also want to thank Dipl-Ing. Stefan Rainer for introducing me to the topic of my thesis, the fruitful discussions, as well as the enormous patience and time he devoted to my questions and problems. As parts of this thesis were developed at the McMaster University in Canada I want to thank my supervisor Prof. Nicholas Kevlahan, for supporting me not only during the research, but also during my whole exchange at McMaster. I also want to take this opportunity to thank the Joint Study Program of the University of Innsbruck that made the one year exchange possible. My gratitude also goes to my colleagues at both Universities like Katharina, Christian, Georg, Tobias and Julian, for supporting me during my studies with an open ear for questions and welcome distractions, if needed. For the technical support with the computation systems used in the example part of this thesis, I want to thank Martin Pöll and the whole ZID team of the University of Innsbruck. Apart of this I want to thank Linda Quehenberger and Andreas Holzmann for linguistic assistance. My gratitude also goes to my family and friends for the support and giving me the opportunity to study. I want to thank the Tiroler Wissenschaftsfond for the financial suppor