Dr. Ralph D. Semmel is the eighth director of the ÃØÃÜÖ±²¥ Applied Physics Laboratory (APL). As director, Dr. Semmel leads the nation’s largest university affiliated research center, which performs research and development on behalf of the Department of Defense, the Intelligence Community, NASA, and other federal agencies. The Laboratory has more than 9,000 staff members who are making critical contributions to a wide variety of nationally and globally significant technical and scientific challenges.