1. Center for in Silico Protein Science, Korea Institute for Advanced Study; Seoul 130-722 Korea
2. Center for Advanced Computation, Korea Institute for Advanced Study; Seoul 130-722 Korea
3. School of Computational Sciences, Korea Institute for Advanced Study; Seoul 130-722 Korea
4. Department of Physics; University of Suwon; Hwaseong-Si Gyeonggi-do 445-743 Korea