Acknowledgement
There are many people to thank, but I cannot write all of them, at the risk of forgetting someone. So, I thank those who have helped me over the years with my research, that have supported me, encouraged and often suggested the way forward. I would like to thank prof. A.
Monorchio, without which I could not begin this way. I would like to thank Ing. G. Tiberi, for all the very useful theoretical discussions on the methods and principles of electromagnetic to be applied, and also for the kindness and sympathy. I could not find a better guide. Of course, I thank my parents, even if they did not know quite what I was doing, they have always tried to advise me to the best, and have always encouraged me.
But especially, I would to thank my wife, Angela, without which nothing in my life would be possible.