In dictionaries:
Hexaxial reference system
The hexaxial reference system, better known as the Cabrera system, is a convention to present the extremity leads of the 12 lead electrocardiogram, that provides an illustrative logical sequence that helps interpretation of the ECG, especially to determine the heart's electrical axis in the frontal plane.
Military Grid Reference System
The Military Grid Reference SystemDMA Technical Manual 8358.1, Chapter 3.
World Geographic Reference System
a geocode, a grid-based method of specifying locations on the surface of the Earth.
Spatial reference system
A spatial reference system or coordinate reference system is a framework used to precisely measure locations on the surface of Earth as coordinates.
Attitude and heading reference system
An attitude and heading reference system consists of sensors on three axes that provide attitude information for aircraft, including roll, pitch, and yaw.
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