1. Faculty of Engineering Technology, Department of Mechanics of Solids, Surfaces & Systems (MS3), Chair of Elastomer Technology and Engineering, University of Twente, 7500 AE Enschede, The Netherlands
2. Department of Chemical Engineering, Delft University of Technology, 2629 HZ Delft, The Netherlands
3. High Voltage Engineering, Tampere University, P.O. Box 1001, FI-33014 Tampere, Finland
4. VTT Technical Research Centre of Finland Ltd., P.O. Box 1001, FI-33014 Tampere, Finland
5. Department of Electrical, Electronic and Information Engineering “Guglielmo Marconi”, University of Bologna, 40136 Bologna, Italy