Cumulative Damage Models with Replacement Last. - Xufeng Zhao; Keiko Nakayama; Syouji Nakamura (FGIT-ASEA/DRBC/EL, 2011)

Stochastic Applications for e-Learning System. - Syouji Nakamura; Keiko Nakayama; Toshio Nakagawa (IIMSS, 2012)

Optimal study number of stochastic e-learning system. - Syouji Nakamura; Keiko Nakayama; Toshio Nakagawa (Int. J. Knowl. Web Intell., 2013)