- 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, ...
A function giving the variation of contrast transfer factor with frequency.
Industry:Earth science
The German industrial standard for products made by or used in engineering, industry and science. It is also used outside of Germany for many products such as film speed and electrical connectors. Usually written as DIN.
Industry:Earth science
The average period, of about 27½ days, measured from perigee to perigee, during which the Moon completes one revolution around the Earth.
Industry:Earth science
An instrument for measuring the opacity of translucent materials such as photographic negatives, optical filters and liquids. It passes a beam of light through the material and measures the ratio of the intensity of the light emerging from the material to the intensity of the light entering the material. This ratio is the transmissivity; the (optical) density is the logarithm of the reciprocal of the transmissivity. Density and transmissivity depend not only on the material but also on the spectral constitution of the light, the diameter and direction of the beam, and other factors. If the beam is of very small diameter at its place of entry into the material, the instrument is called a micro-densitometer.
Industry:Earth science
A coordinate in a galactic coordinate system. Galactic coordinates are usually designated as galactic longitude, L; galactic latitude, b; and galacto-centric or heliocentric distance, r. Because the constants defining the system have been changed several times, numeric subscripts are usually attached to the letters to identify the particular version with which the symbols are to be used.
Industry:Earth science
(1) The set of points in N-space satisfying a polynomial equation in N variables. In particular, the set of points, in the plane, satisfying a polynomial equation in two variables.
Industry:Earth science
The adjustment made to measured values of gravity or to calculated deflections of the vertical to take account of the assumed deficiency of mass under topographic features for which a topographic correction is also made.
Industry:Earth science
A method of showing relief, in which contour lines appear lighter when indicating illuminated slopes and darker when indicating shadowed slopes. It has also been called illuminated contour, although this usage was probably not intentional.
Industry:Earth science
A tidal constant other than a harmonic tidal constant, e.g., the range of an interval derived directly from measurements of high water and low water.
Industry:Earth science
The origin of a coordinate system and defined by the following original latitudes of five observatories (degrees and minutes are the same for all observatories):<br>
Industry:Earth science
