1.Results The difference values calculated were various with the arch form, the sequence was oval, round, parabola, catenuliform, and hyperbola from big difference to smell.
牙弓深度的差值按从到小的顺序排列为:椭圆形、圆形、抛物形、悬链形、双曲形。
2.An equalarea pseudo cylindrical projection gather is constructed, in which the longitudes are hyperbola being symmetrical to the central meridian and the latitudes are parallel lines.