1. Institute of Control and Computation Engineering, University of Zielona Góra, Prof. Z. Szafrana 2, 65-516 Zielona Góra, Poland
2. NOVA School of Science and Technology, Center of Technology and Systems (UNINOVA-CTS), Associated Lab of Intelligent Systems (LASI), NOVA University Lisbon, 2829-516 Lisbon, Portugal
3. University of Zielona Góra, Prof. Z. Szafrana 2, 65-516 Zielona Góra, Poland