都市・交通の視点から、地球温暖化への適応策（ITSによる車の賢い利用、低公害車の普及、車の共同利用、ライフスタイルなど）、軽減策（都市構造、エネルギー消費、総合交通体系、公共交通利用促進、自動車利用抑制など）、そして、移行策（パラトランジットやガバナンス）などの持続可能な発展と都市・交通を研究してきている。途上国について、世帯エネルギー消費からみたエコライフ、雇用と社会的平等性からみたパラトランジットシステムの持続可能な発展、交通システムの環境効率性評価、交通部門の環境モニタリング、環境ガバナンスなどを研究してきている。研究成果としてEnergy Policy, Environment and Planning B, Transportation Research Record, EASTS最高峰雑誌Asian Transport Studies、土木計画学研究論文集などにて83編査読付き論文、他119編論文を公表し、2005年にアジア交通学会八十島賞（最優秀論文賞）を、2007年に国際安全学会最優秀論文賞を、2010年にタイ交通学会第1回国際会議最優秀論文賞をそれぞれ受賞した。（2013年4月時点）
I have conducted various studies on sustainable development in the context of urban and transportation systems. The research topics cover adaptation measures to global warming (smart use of car based on ITS, low-emission vehicles, car sharing, lifestyle, etc.), mitigation measures (urban form, energy consumption, comprehensive transportation systems, promotion of public transportation systems, control of car ownership and usage, etc.), and transition measures (paratransit systems, urban governance, etc.). Related to developing countries, various studies have been carried out related to eco-life study from the perspective of household energy consumption, sustainable development by making better use of paratransit systems from the perspective of employment and social equity, evaluation of environmental efficiency of transportation systems, environmental monitoring in transport sector, and environmental governance, etc. As of April 2013, 83 refereed papers and 119 other papers were published in international recognized journals such as Energy Policy (SCI), Environment and Planning B (SCI), Transportation Research Record (SCI), and ATS (Asian Transport Studies) of EASTS. One of the papers was awarded as Best Paper Prize (Yasojima Prize) by the EASTS (Eastern Asia Society for Transportation Studies) in 2005, one as Best Paper Award by the IATSS (International Association of Traffic and Safety Sciences) in 2008, and the other as Best Paper Award of the 1st International Conference on the Future of Human Mobility by Thai Society for Transportation and Traffic Studies in 2010.
Five major pagers are as follows:
- Representing household energy consumption behavior in Beijing with the consideration of in-home and out-of-home interdependence, Energy Policy, 39(7), 4168-4177 (Special Section: Renewable energy policy and development) (Biying YU, Junyi ZHANG and Akimasa FUJIWARA, 2011)
- Scobit-based panel analysis of public transport users’ multitasking behavior. Transportation Research Record, 2157, 46-53 (Junyi ZHANG and H.J.P. TIMMERMANS, 2010)
- Motorization in Asia: 14 Countries and Three Metropolitan Areas. IATSS (International Association of Traffic and Safety Sciences) Research, 31 (1), 46-58 (Metin SENBIL, Junyi ZHANG and Akimasa FUJIWARA, 2007) (IATSS Best Paper Award)
- Evaluating sustainability of urban development in developing countries incorporating dynamic cause-effect relationships over time. Journal of the Eastern Asia Society for Transportation Studies, 6, 4349-4364 (Akimasa FUJIWARA, Junyi ZHANG, Backjin LEE and M.R.M. DA CRUZ, 2005) (EASTS Yasojima Prize: Best of EASTS Best Paper Awards)
- Comparative analysis of travel patterns in the developing cities based on a hybrid model. Journal of the Eastern Asia Society for Transportation Studies, 6, 4333-4348 (Junyi ZHANG, Akimasa FUJIWARA and Makoto CHIKARAISHI, 2005)