150414-N-PO203-024 NATIONAL HARBOR, Md. (April 14, 2015) Rear Adm. Mat Winter, chief of naval research, holds a press conference at the joint Office of Naval Research (ONR), Naval Research Laboratory, and Marine Corps Warfighting Laboratory exhibit during the Navy League's 50th annual Sea-Air-Space Exposition. Winter talked about various ONR technologies on display during the exposition including the large displacement unmanned undersea vehicle-innovative naval prototype, low-cost unmanned aerial vehicle swarming technology, ground-based air defense on-the-move, and the ONR's medium displacement unmanned surface vehicle. (U.S. Navy photo by John F. Williams/Released)