1991-1992 Kumamoto National College of Technology, Department of Information and Communication Engineering, Research Assistant1992-1993 Toyohashi University of Technology, tecnology development center, Research Assistant1993-1997 Kumamoto National College of Technology, Department of Information and Communication Engineering, Research Assistant1998 Kumamoto National College of Technology, Department of Information and Communication Engineering, Lecturer1998-2000 Kumamoto National College of Technology, Department of Electronic Engineering, Lecturer2000-2002 Kumamoto National College of Technology, Department of Electronic Engineering, Associate Professor2003 IMEC (Interuniversity MicroElectronics Center), Visiting Researcher.2004-2005 Kumamoto National College of Technology, Department of Electronic Engineering, Associate Professor