1. Department of Systems and EnergyUniversity of CampinasAv. Albert Einstein 400CampinasBrazil
2. Group of Automation and Integrated SystemsUNESP – Univ. Estadual PaulistaAv. Três de Março 511SorocabaBrazil
3. Department of Electrical and Electronic EngineeringUniversity of NottinghamNG7 2RDNottinghamUK