A system of assigning dates to events. There are three fundamental scales: Ephemeris Time, time based upon the rotation of the earth, and atomic time or time obtained by counting the cycles of a signal in resonance with certain kinds of atoms. Ephemeris Time (ET), the independent variable in the gravitational theories of the solar system, is the scale used by astronomers as the tabular argument of the precise, fundamental ephemerides of the sun, moon, and planets. Universal Time (UT1), time based on the rotation of the earth, is the scale used by astronomers as the tabular argument for most other ephemerides, e.g., the Nautical Almanac. Although ET and UT1 differ in concept, both are determined in arrears from astronomical observations and are extrapolated into the future based on International Atomic Time (TAI). Coordinated Universal Time (UTC) is the scale disseminated by most broadcast time services; it differs from TAI by an integral number of seconds.
Related Terms |
SAFETY CONTROL
Device to stop unit, equipment or system if unsafe pressure and/or temperatures and/or dangerous conditions are reached.
|
AGGLOMERATION
The potential of the system for particle attraction and adhesion.
|
REMOTE REFRIGERATING SYSTEM
Refrigerating system in which condensing unit is away from space to be cooled.
|
REFRIGERATING CAPACITY
The ability of a system to remove heat as compared with the cooling effect produced by melting of ice.
|
ADIABATIC PROCESS
A thermo-dynamic process in which no heat is extracted from or added to the system of the process.
|
ACCELERATION
The time rate of change of velocity; i.e., the derivative of velocity; with respect to time.
|
RUNNING TIME
Amount of time an unit, equipment or system is run per hour or per 24 hours.
|
RUNNING TIME
Amount of time an unit, equipment or system is run per hour or per 24 hours.
|
GROUP REPETITION INTERVAL
The specified time interval of a Loran C chain for all stations of the chain to transmit their pulse groups. For each chain a minimum group repetition interval (GRI) is selected of sufficient duration to provide time for each station to transmit its pulse group and additional time between each pulse group so that signals from two or more stations cannot overlap in time anywhere within the coverage area. The GRI is normally stated in terms of tens of microseconds; i.e., the GRI having a duration of 79,900 microseconds is stated as 7900.
|
ACID CONDITION IN SYSTEM
Condition in which refrigerant or oil in a system, is mixed with vapor and fluids that are acidic in nature.
|
