Glossary
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T
TU Transceiver Unit
U
UTC Coordinated Universal Time. The International Atomic Time (TAI)
with leap seconds added at irregular intervals to compensate for
the Earth’s slowing rotation. Leap seconds are used to allow UTC
to closely track UT1, which is mean solar time at the Royal
Observatory, Greenwich.
V
VDR Voyage Data Recorder, a data recording system designed for all
vessels required to comply with the IMO’s International
Convention SOLAS Requirements in order to collect data from
various sensors on board the vessel.
VHF Very High Frequency