- Branche: 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 resistance of a material to the transmission of light through it. The measure of opacity is the reciprocal of the transmissivity.
Industry:Earth science
A columnar rock rising from the depths and constituting a menace to navigation on the surface.
Industry:Earth science
A geodetic system covering all of North America and extending into Greenland, developed by coordinated efforts between the countries covered by the system, and essentially completed by 1988. The datum of the North American Datum 1983 geodetic system is, for practical purposes, equivalent to that of the World Geodetic System 1984. Coordinates of points in the system are not, however, the same because they are determined by including in the adjustment besides data from the TRANSIT (Navy Navigation Satellite System), data from traverses, triangulation and the Global Positioning System.
Industry:Earth science
Phototriangulation in which the coordinates of the control points are obtained purely by computation. When done using aerial photographs, the process is referred to as analytical triangulation or analytical aerotriangulation.
Industry:Earth science
Aerotriangulation in which the length of the air base is derived from the altitude at which the photographs were taken, as measured by an altimeter (typically, a radar altimeter). Otherwise similar to radial aerotriangulation.
Industry:Earth science
(1) The revision of a map by making a survey with a planetable. (2) Revision done directly on maps, or on transparent sheets overlying maps, fastened to a planetable and carried out by the usually procedures for surveying using a planetable.
Industry:Earth science
The set of instructions that a computing machine uses to perform its basic functions.
Industry:Earth science
(1) The total movement of a pendulum from the time it passes in a specified direction through a specified position until it again passes in the same direction through the same position. (2) The total movement of a pendulum between its passing from one extreme position to its next passage in the same direction to an extreme position.
Industry:Earth science
The horizontal-control datum which is defined by the following coordinates of the origin and azimuth (clockwise from South) on the Clarke spheroid of 1866; the origin is at Meades Ranch:<br>
Industry:Earth science
