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－　　－36Takuya MACHIDAAssistant Professor, Department of Liberal Arts and Basic SciencesTakuya Machida is an assistant professor at the College of Industrial Technology, Nihon University. He received his B.S. in Engineering in 2005, his M.S. in Engineering in 2007, and his Ph.D. in Engineering in 2010, all from Yokohama National University. He was a postdoctoral fellow, the Meiji Institute for Advanced Study of Mathematical Sciences, Meiji University (April 2010– March 2013), a research fellow, the Japan Society for the Promotion of Science (April 2013–March 2016), and a postdoctoral scholar, the Department of Mathematics, University of California, Berkeley (August 2013–January 2015). He has been a member of the Mathematical Society of Japan since April 2010. Dr. Machida studies quantum walks, which are quantum analogues to random walks, focusing on long-time limit theorems. Long-time limit theorems describe how quantum walkers approximately distribute in space after they have updated their systems a large number of times. He has mathematically proven the limit theorems for quantum walks since he started working on quantum walks.Research Achievements1)A limit distribution for a quantum walk driven by a five-diagonal unitary matrix, Quantum Information and Computation, Vol.21 No.1&2, pp.19-36 (2021).2)Limit distribution of a time-dependent quantum walk on the half line, Quantum Information Processing, Vol.19, 296 (2020).3)Some limit laws for quantum walks with applications to a version of the Parrondo paradox, Quantum Information Processing, Vol.17(9), 241 (2018).4)A limit theorem for a splitting distribution of a quantum walk, International Journal of Quantum Information, Vol.16, No.3, 1850023 (2018).5)A quantum walk on the half line with a particular initial state, Quantum Information Processing, Vol.15, No.8, pp. 3101-3119 (2016).