As the situation may require, such as in directions on medical charts by doctors for the benefit of nursing staff indicating actions that may be taken at their discretion depending on patient condition; or likewise instructions to a patient on a prescription indicating they may take the medicine if and when they feel the need for it
In DOS and OS/2, the logical device name for a printer, usually the first parallel port, which is also known as LPT1
Pseudo-random noise Each GPS satellite generates its own distinctive PRN code, which is modulated onto each carrier The PRN code serves as identification of the satellite, as a timing signal, and as a subcarrier for the navigation data
Pseudorandom noise, a sequence of digital 1s and 0s which appears to be randomly distributed like noise, but which can be exactly reproduced The important property of PRN codes is that they have a low autocorrelation value for all delays or lags except when they are exactly coincident Each NAVSTAR satellite has its own unique C/A and P pseudorandom-noise codes
Pseudo-Random Noise -- one of 32 possible "gold codes" assigned to each GPS satellite; the PRN number is used in this database to identify different GPS satellites