- 行业: Earth science
- Number of terms: 93452
- Number of blossaries: 0
- Company Profile:
Founded in 1941, the American Congress on Surveying and Mapping (ACSM) is an international association representing the interests of professionals in surveying, mapping and communicating spatial data relating to the Earth's surface. Today, ACSM's members include more than 7,000 surveyors, ...
The accuracy with which the coordinates of points determined from a map agree with the coordinates determined by survey or other independent means accepted as accurate.
Industry:Earth science
A surface of rotation whose meridional section is defined by the equation r = a sech(b ( Ψ + c)), where a, b and c are constants, Ψ is the isometric latitude and r is the perpendicular distance from the axis of rotation to the surface. The constants are chosen to make the aposphere osculate the spheroid (with which it has a common axis or rotation) along some parallel that passes through the center of the region for which a transformation is required.
Industry:Earth science
The time elapsed since the preceding new moon. It is usually expressed in days.
Industry:Earth science
The reduction in the intensity of light, on passing through a medium, because the light is transformed by the medium into some other, invisible form of energy such as heat. It should be distinguished from scattering, which diminishes the intensity of a beam by spreading the direction of propagation over a larger solid angle.
Industry:Earth science
The shortest line that can be drawn thru the center and from one side to the other of an ellipse or ellipsoid.
Industry:Earth science
A particular and very common make of gyroscopic compass, named after its inventor and manufacturer.
Industry:Earth science
The method of least squares, using already available information about the covariances of the unknowns to derive, from new measurements, new values of the unknowns and their covariances.
Industry:Earth science
(1) The ratio of the length of a segment AB to the length of the projected segment A'B', with the center of projection at infinity. (2) The same as the previous definition, the projection being orthogonal. Either meaning seems to be used by only a small number of photogrammetrists. The term scale is more generally used and is more appropriate.
Industry:Earth science
