1. Fraunhofer Institute for Manufacturing Engineering and Automation, Stuttgart, Germany
2. Research Institute of Sensors, Signals and Systems, Heriot-Watt University, Edinburgh, U.K.
3. Department of Mathematical Sciences, University of Greenwich, London, U.K.
4. Hochschule Ravensburg-Weingarten, Württemberg, Germany
5. Engineering of Adaptive Systems Division, Fraunhofer Institute for Integrated Circuits, Dresden, Germany