1. VTT Technical Research Centre of Finland Ltd,Espoo,VTT,Finland,POB 1000FI-02044
2. Aalto University,Department of Electrical Engineering and Automation,Espoo,Aalto,Finland,POB 15500FI-00076
3. Aalto University,Department of Mechanical Engineering,Espoo,Aalto,Finland,POB 15500FI-00076