- Industry: 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, ...
A map on which lines are drawn true to scale. It is not possible to draw an isometric map of features on a sphere or any part thereof. But if the scale of the map is large enough and the area of the depicted part is small enough, error in scale can be made insignificant.
Industry:Earth science
A condition equation which expresses the relationship between the fixed longitudes of two points connected by traverse or by triangulation. When traverse or triangulation connects two points whose longitudes have been fixed by direct observation or by previous surveys, a longitude equation is used to make the longitude of either point, as computed through the survey from the other point, agree with its longitude as previously fixed.
Industry:Earth science
A pendulum whose form is such that a change of temperature causes minimal change in the length of the pendulum.
Industry:Earth science
Magnification in the direction of the optical axis.
Industry:Earth science
A map showing the different types of soil, rock, etc. Each type is usually indicated by a characteristic shading or color.
Industry:Earth science
(1) For maps prepared before 1962, a modified polyconic map projection with two standard meridians along which the scale is held exact. The geographic meridians are represented by straight lines connecting points on the top and bottom parallels of latitude. The lines representing the parallels of latitude are non concentric arcs of circles. Up to latitude 60<sup>o</sup>, each sheet of the series depicts a region between 4<sup>o</sup> of latitude and 6<sup>o</sup> of longitude. Between latitudes 60<sup>o</sup> and 76<sup>o</sup>, the sheets are double width, so each covers 4<sup>o</sup> of latitude and 12<sup>o</sup> of longitude. From 76<sup>o</sup> to 84<sup>o</sup>, the sheets are 24<sup>o</sup> wide. The scale of the map is 1:1 000 000; for this reason, it is also called the millionth scale map of the world. The map projection was devised by Lallemand about 1909. (2) In 1962, this map projection was replaced, for the regions between 84<sup>o</sup> N and 80<sup>o</sup> S, by Lambert's conformal conical map projection with two standard parallels. At the poles, the polar stereographic map projection was used.
Industry:Earth science
A matrix having N rows and M columns, with N different from M.
Industry:Earth science
The tidal datum for the Netherlands, referred to the standard tide-gage at Amsterdam (Normaal Amsterdams Peil). This tidal datum has been used by many European countries as a common datum for leveling.
Industry:Earth science
A mark which, while actually part of the optical system of a stereoscope, appears to occupy a position in the three-dimensional space perceived by stereoscopic fusion of a pair of photographs, and used as a reference in examining or measuring the stereoscopic model. The mark may be formed, in a binocular system, (a) by one real mark lying in the image-space of the system; (b) by two real marks lying in that image-space; (c) by two real marks lying in the plane of the photographs themselves; or (d) by two virtual marks lying in the planes of the images.
Industry:Earth science
A graduated line used to measure the speed of a vessel through the water or to measure the speed of the current from a vessel at anchor.
Industry:Earth science
