1. Institute for Mathematics and Scientific Computing , University of Graz , NAWI Graz, Heinrichstrasse 36, 8010 Graz , Austria ; and Lavrentyev Institute of Hydrodynamics, Siberian Branch of the Russian Academy of Sciences, 630090, Novosibirsk, Russia
2. Faculty of Information Design and Sociology , Hiroshima Kokusai Gakuin University , 6-20-1, Aki-ku , Hiroshima , 739-0321 , Japan