150204-N-PO203-371 WASHINGTON, D.C. (Feb. 4, 2015) Chief of Naval Operations Adm. Jonathan Greenert outlines his top three priorities for the science and technology community during the Naval Future Force Science and Technology (S&T) EXPO. Greenert challenged more than 2700 attendees to help reduce use of shipboard gunpowder, advance unmanned undersea vehicle propulsion, and protect data and IT infrastructure. (U.S. Navy photo by John F. Williams/Released)