- 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, ...
That configuration, in an optical system consisting of a mirror followed by a lens, in which the chief rays passing through the center of aperture of the lens diverge in image space (i.e., create a virtual image). This type of optical system is used for taking photographs (of a model) having more or less arbitrary viewpoints, i.e., from more or less arbitrary perspectives.
Industry:Earth science
A mounting allowing the instrument to be rotated about a fixed horizontal axis and/or an axis perpendicular thereto. Note that the x-y mounting differs from, the al-azimuth mounting in that in the latter type, the vertical axis is fixed.
Industry:Earth science
A map showing the contours of the bottom of a body of water. It is a topographic map of underwater regions. It differs from a bathymetric chart in containing more topographic information and little or no navigational information.
Industry:Earth science
A map projection of the whole sphere into the region within an ellipse.
Industry:Earth science
The process of changing the values associated with the stations of a network, and/or the geometric relationships (distances, angles, etc.) between the stations according to some principle or rule, in order to obtain better values or geometric relationships.
Industry:Earth science
A number giving a count of physical objects. For example, in the phrase eighteen satellites, eighteen is a concrete number.
Industry:Earth science
The additional exposures made beyond the boundary of a region to be photographed. It consists, usually, of two exposures at the ends of each strip, to ensure complete, stereoscopic coverage.
Industry:Earth science
A machine used in making relief models and permitting the three-dimensional terrain base to be cut using a flat contour-map as a guide.
Industry:Earth science
A sheet of paper having on its surface a layer of barium oxide to provide a reflecting surface and, over this, a layer of emulsion containing light-sensitive halides.
Industry:Earth science
(1) Any plane passing through a point on the Earth and containing the zenith (and nadir) of that point. A vertical plane containing the zenith must also contain the nadir. The planes of the celestial meridian and of the prime vertical circle are vertical planes. (2) A plane perpendicular to a horizontal plane and within which angles and directions are measured. (3) A plane containing a plumb line. This is probably an empty definition, because a plumb line is in general not planar.
Industry:Earth science
