1. Graduate School of System Informatics, Kobe University, Kobe 657-8501, Japan
2. Department of Physics, Kumamoto University, Kumamoto 860-8555, Japan
3. Faculty of Science and Engineering, Kyushu Sangyo University, Fukuoka 813-8503, Japan
4. Collaboratory for Advanced Computing and Simulations, University of Southern California, Los Angeles, California 90089-0242, USA