one of the most important problems in geodesy is the unification of height datum. generally in geodesy; there are two types of height systems, the geometrical height based on ellipsoid and the physical height based on gravity-defined surface (zhang et al, 2009).local height datum is determined according to mean sea level (msl). in regarding to mismatch of mean sea level and geoid, on the one ha...

SUMMARY The fast development of Global Positioning System (GPS) technology provides more precise and rapid surveying in geodetic applications than the traditional terrestrial positioning techniques. Therefore, considerable savings on time, labour and cost are achieved by GPS measurements. The geometric height supplied by GPS is ellipsoidal height and it needs to be transformed to orthometric he...

nowadays, combination of gps heights with orthometric heights, derived from precise leveling, is broadly used to obtain point-wise solutions of the geoid, which is called “gps/leveling geoid”. the “gps/leveling geoid” is commonly used to constrain the gravimetric geoid solutions in a least squares surface fitting process. in this paper, unlike the usual application, the “gps/leveling geoid” is ...

The determination of the orthometric height from geometric leveling has practical difficulties that, despite a number of scientific and technological advances, passed a century without substantial modifications or advances. Currently, the Global Navigation Satellite System (GNSS) has been used with reasonable success for orthometric height determination. With a sufficient number of benchmarks w...

the simple method for height determination is spirit leveling. the leveled height differences are path-dependent. ergo height from spirit leveling is not unique. the problem can be solved by converting the path-dependent leveled height differences into unique path-independent height differences (vanicek and krakiwsky, 1986). the difference between the potentials of two close equipotential surfa...