N
Geodetic Height ( h) Orthometric Height ( H). Geoid Undulations ( N)
N = h - H
N . N 9 21 .
N Global Geoid Models . . OSU91A EGM96 . - - EGM96 80 + - 80 ( GPS) . Software GPS h H. GPS GPS .
.
( 5 5 ) N 4 ( h GPS 4 H ) Interpolation N h H .