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Federal
Geoid Height and Deflections of the Vertical Models NGDA
National Oceanic and Atmospheric Administration, Department of Commerce —
In Gauss' words, the geoid is "the mathematical figure of the Earth". This figure is an equipotential surface coincident with the idealized mean sea surface. The... -
Federal
Calibration Base Lines for Electronic Distance Measuring Instruments (EDMI)
National Oceanic and Atmospheric Administration, Department of Commerce —
A calibration base line (CBL) is a precisely measured, straight-line course of approximately 1,400 m used to calibrate Electronic Distance Measuring Instruments...