Professor Yuan has taught graduate courses in statistical mechanics, quantum mechanics, and mathematical physics for years, and special topics in biophysics and in atomic and molecular physics. He has also taught various undergraduate courses, such as general physics, classical mechanics, and thermodynamics. He has conducted research in laser physics, interactions between laser and atoms and molecules, intense laser field effects, nonlinear dynamics, chaos, quantum chaos. More recently, he has carried out research in several areas of biophysics, including protein folding/unfolding, macromolecular crowding effects on protein stability and reactions, signaling pathways related to cancer and diabetes, stochastic dynamics, and non-equilibrium thermodynamics.
Professor Yuan was an NWO fellow at University of Utrecht, the Netherland, a visitor at University of Kaiserslautern, Germany, Technion- Israel Institute of Technology, Israel, University of Kansas, University of New Mexico, University of Pennsylvania, ITAMP, Harvard University, National Taiwan University, National Chiao-Tung University, National Central University, and Institute of Physics, Academia Sinica, Taiwan. He has visited and collaborated with scientists at the Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, for more than 15 years. He is an Honorary Professor at Hunan Normal University, Changsa, China, and a visitor at University of Science and Technology of China, Hefei, Lanzhou University, Sun Yat-Sen University, Guangzhou, Jilin University, Beijing Normal University.
He was elected a Fellow of American Physical Society in 1998 and is a member of American Chemical Society, Biophysical Society, and Sigma Xi. He was a co-organizer of several international conferences and workshops on chaos and quantum chaos and a co-editor of Quantum Nonintegrability, 'Directions in Chaos', Volume IV (World Scientific, Singapore, 1992) and Quantum Dynamics of Chaotic Systems (Gordon and Breach, 1993). He served on the Editorial Advisory Board of International Journal of Physics, Group Theory, and Nonlinear Dynamics.