Các thuật ngữ chính trong trắc địa chuyên nghiệp và công nghệ địa không gian.
HDOP is a dimensionless factor that describes the geometric strength of satellite positions and their effect on the accuracy of horizontal positioning in GNSS surveying.
A horizontal angle is the angular measurement between two lines or directions in a horizontal plane, typically measured from a point of observation to establish position and direction in surveying work.
A measurement of the horizontal angle between a reference direction and a target point, obtained by reading the graduated horizontal circle on a surveying instrument.
A hydrographic survey is the systematic measurement and mapping of underwater and coastal water features, including depths, seafloor characteristics, and navigational hazards.