1. Institute
of Applied Materials, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
2. Institute
of Materials and Processes, University of Applied Sciences, 76133 Karlsruhe, Germany
3. Institute
of Applied Materials, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
4. Faculty
of Mathematics, University of Regensburg, 93053 Regensburg, Germany