As used in this subchapter—
(1)
the term “oceanographic research vessel” means a vessel which the Secretary of the department in which the Coast Guard is operating finds is being employed exclusively in instruction in oceanography or limnology, or both, or exclusively in oceanographic research, including, but not limited to, such studies pertaining to the sea as seismic, gravity meter and magnetic exploration and other marine geophysical or geological surveys, atmospheric research, and biological research;
(2)
the term “scientific personnel” means persons who are aboard a vessel solely for the purpose of engaging in scientific research, instructing, or receiving instruction, in oceanography or limnology.