1. Department of Life Design, Osaka International College, 6-21-57 Tohdacho, Moriguchi, Osaka 570-8555, Japan
2. Department of Computer Science, Osaka Electro-Communication University, 1130-70 Kiyotaki, Shijonawate, Osaka 575-0063, Japan
3. Kashina System Co., Ltd., 116-22 Hiratacho, Hikone, Shiga 522-0041, Japan
4. Department of Human Information Engineering, Okayama Prefectural University, 111 Kuboki, Soja, Okayama 719-1197, Japan