2020 - 2024 Fundamentals and developments for Chinese diplomatics based on an analysis of historical papers
2017 - 2021 Research on major traffic routes in pre-modern China mainly based on surveys of pass, ferry and road sites
2015 - 2019 An Innovative study on East Asian historical documents, excavated by explorers across Europe in the Silk Road, through comprehensive re-examination
2013 - 2018 A Study on the Ancient Japanese Manuscripts of Chinese Classical Books
2013 - 2017 The environmental historical study of traffic routes and checking stations and ferry crossings in pre-modern China
2013 - 2017 A Comprehensive Study on Control of the Populace under the Ritsuryo System: A Comparative Study of Ancient Japan and the Tang and the Song Statutes
2011 - 2015 Research on Tiansheng Statute and its character as historical texts
2009 - 2012 Research in the Chines texts which were discovered in Dunhuang, Turfan, etc. and now kept in Russia
2009 - 2011 A Comparative Study of the Code-Statute Law in Ancient Japan and the Tang and the Song: Towards the Compilation of a New Torei Shui
2006 - 2009 A Study of the Litigious Chinese Society in East Asian History
2006 - 2008 A Study on Exile as punishment during the Han, Wei and Six Dynasties
2005 - 2008 A New Stage of Comparative Study of the Code-Statute Law in Ancient Japan and the Tang
2000 - 2002 Comprehensive Study on the Penalty System between Tang and Song Period
1994 - 1995 Investigation on the Chinese manuscripts in Europe
1994 - 1994 唐宋変革期における刑制の変化
1989 - 1992 Legal institutions and society in pre-modern China