deteeting the ground point with low frequency electric current signal changing its frequency
few ground control point
GCP Ground Control Point
ground control point for aerial photography
ground elevation control
The wrong of elevation point with contour line
air-ground control radio station
airport ground control tower
assumed ground elevation
COMPOSITE GROUND WITH DOUBLE SOIL STRATA
composite ground with granular columns
composite ground with rigid piles
conical flask with ground-in glass stopper
coordination with ground environment
cover ground with plastic film
covering with ground sheeting