He is certified by the American Board of Radiology in radiation therapy physics. He was appointed as Assistant Professor and then Associate Professor at the University of Virginia prior to joining UCLA, where he was promoted to tenured full Professor. Dr. Sheng has wide research interests including treatment planning optimization, particle therapy, image reconstruction and processing, radiobiology, and novel radiotherapy instrumentations. He runs an active and productive research group consisting of junior faculty, postdoctoral researchers and graduate students. He is supported by NIH, DOE and industrial partners. He is a fellow of American Association of Physicists in Medicine.