1) One person operation 
[dolphin] Opo was a bottlenose dolphin who became famous throughout New Zealand during the summer of 1955-56 for playing with the children of the small town of Opononi on the Hokianga harbour. Opo was a wild dolphin who started following fishing boats around Opononi in early 1955 after her mother had been killed, and would swim daily in the...
One person operation
Organ Procurement Organization
One Person Operation; the standard train operating regime used on London Underground. Conversion from two-person crews began in 1984 and was finally completed in 2000.