Kento Aida received Dr. Eng. in electrical engineering from Waseda University in 1997. He became a research associate at Waseda University in 1992. He joined Tokyo Institute of Technology and became a research scientist at the Department of Mathematical and Computing Sciences in 1997, an assistant professor at the Department of Computational Intelligence and Systems Science in 1999, and an associate professor at the Department of Information Processing in 2003, respectively. He is now a professor at National Institute of Informatics and a visiting professor at the Department of Information Processing in Tokyo Institute of Technology from 2007. He was also a researcher at PRESTO in Japan Science and Technology Agency (JST) from 2001 through 2005, and a research scholar at the Information and Computer Sciences Department in University of Hawai`i in 2007.