- 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 line, continuous or broken, drawn so that the area between it and a given straight line is exactly 1, while the area between any segment of the first line and the straight line is proportional to the frequency of the quantity represented by the line. Alternatively, it is the graph of the corresponding frequency function.
Industry:Earth science
The angle from a specified great-circle used as reference to the great circle in question.
Industry:Earth science
An antenna consisting of two separate, open ended conductors in line and a short distance apart. The adjacent ends are connected to the terminals of a radio receiver or radio transmitter. Usually called a dipole for short when no confusion is likely. Dipole antennas are easily made, easily erected, and take up little space if made for the frequencies at which most satellites transmit or receive.
Industry:Earth science
A curve representing the linear distortion caused by a lens system. It is plotted with radial distances of image points from the optical axis as abscissas and with radial displacements from their correct (undistorted) distances as ordinates.
Industry:Earth science
(1) A ditch constructed to divert water from its natural channel. (2) An open, artificial waterway approximately parallel to the top of a cut backslope for preventing surficial water from flowing over the slopes of a cut or against the foot of an embankment. Its purpose is protection of the slope from erosion.
Industry:Earth science
One of a set of any three numbers proportional to the three direction cosines of a line.
Industry:Earth science
The distance from the intersection of the tangents (vertex) of a circular curve to its midpoint, measured along the line extending between the vertex and its center of radius.
Industry:Earth science
(1) A set of precisely spaced, parallel lines which cause incident electromagnetic radiation to be diffracted either upon reflection or upon transmission between the lines. (2) The ruled piece of metal or other material causing diffraction. Diffraction gratings for radio waves usually consist of closely spaced wires held in a frame. Diffraction gratings for radiation at wavelengths from the infrared to ultraviolet are ruled by a graving tool on a plane or curved sheet of metal, or may be produced by photographing onto a glass plate a set of inked lines on paper. At very short wavelengths, the lattices of crystals serve as diffraction gratings.
Industry:Earth science
That digit, in a number, which contributes most to the value of the number.
Industry:Earth science