1. Czestochowa University of Technology , al. Armii Krajowej 36, 42-200 Częstochowa , Poland
2. Institute of Information Technology , Lodz University of Technology , Lodz , Poland
3. School of Computer Science and Engineering , Xi’an University of Technology , China
4. Information Technology Institute , University of Social Sciences , 90-113 Łodz Clark University Worcester, MA 01610, USA