Institute of Informatics, Silesian University of Technology, Akademicka 16, Gliwice, 44-100, Poland. dariusz.mrozek@polsl.pl|Institute of Informatics, Silesian University of Technology, Akademicka 16, Gliwice, 44-100, Poland. dariusz.mrozek@polsl.pl|Institute of Informatics, Silesian University of Technology, Akademicka 16, Gliwice, 44-100, Poland. dariusz.mrozek@polsl.pl