Affiliation: | (1) Institute of Automatics, Academy of Mining and Metallurgy, al. Mickiewicza 30/B1, rm.314, PL-30-059 Cracow, Poland;(2) Department of Mathematics, Facultés Universitaires Notre-Dame de la Paix, 8, Rempart de la Vierge, B-5000 Namur, Belgium |