He joined Northwestern University, Evanston, IL, USA, as an Assistant Professor in 1987. In 2000, he joined the Computer Science Department, University of California at Los Angeles, Los Angeles, CA, USA, where he is currently a Distinguished Professor. He was in collaborative with many industries. In 2000, he was a Co-Founder of two companies, which were both acquired around 2004. He is currently a Co-Founder of three companies in healthcare technology. He has authored or co-authored over 600 papers and co-authored 5 books. He is a named inventor on many U.S. patents. His current research interests include embedded computing with emphasis on health analytics.