- 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 graphical method of rectifying a photograph point by point, using the invariance of the cross ratio in a geometric projection from ranges of points in the original to corresponding points in the rectified version.
Industry:Earth science
(1) A system for representing numbers as a power series in the bases 10 and 60, with coefficients in the decimal system, so that coefficients of successive powers of 60 lie between 0 and 59. (2) An application of the sexagesimal number system to representing divisions of the circle. The circle is first divided into 360 parts called degrees (<sup>o</sup>), each degree is divided into 60 parts called minutes (') and each minute is divided into 60 parts called seconds ("). Each second is divided according to the decimal number system e.g., 5<sup>o</sup> 3' 2.3455". (3) An application of the sexagesimal number system to representing divisions of the day. The day is first divided into 24 parts called hours(h), each hour is divided into 60 parts called minutes (m), and each minute is divided into 60 parts called seconds (s). Each second is divided according to the decimal number system, e..g., 5h 3m 2.325s. Because minute and second are used for divisions of the hour as well as of the degree, they are written as minute of arc, second of arc, minute of time and second of time if confusion would otherwise be possible. However, if the symbols for these units are used, or if there is no possibility of misunderstanding, use of terms like minute of arc or arc-second pretentious.
Industry:Earth science
Such motion, in a mechanism, as is not transmitted to connected or related parts because parts of the mechanism fit loosely.
Industry:Earth science
A variation in the tide or tidal currents associated with changes in the phase of the Moon. At new moon and full moon (springs), the tide-producing forces of the Sun and Moon act in conjunction, causing greater than average tides (spring tides) and speed of tidal currents. At first and last quarters of the Moon (neaps), the tide-producing forces oppose each other, causing smaller than average tide (neap tide) and tidal currents.
Industry:Earth science
Flattened, as opposed to prolate (lengthened). In mathematics and physics, it is used mostly to denote a spheroid (rotational ellipsoid) having the minor axis shorter than the other two axes, as contrasted to a prolate spheroid, which has its minor axis longer than the other two axes. It is used in the same way in geodesy except in gravimetric geodesy, where rotational ellipsoid is used instead of spheroid.
Industry:Earth science
The quantity a<sup>3</sup>b ω/GM, in which G is the gravitational constant, M the mass of the Earth, a the equatorial radius and b of an ellipsoid representing the Earth, and ω the angular rate of rotation.
Industry:Earth science
A single direction or location which is the weighted average of a number of observed directions or locations.
Industry:Earth science
The difference in the absolute stereoscopic parallaxes of two points imaged on a pair of photographs. It is customarily used in determining the differences in heights of objects.
Industry:Earth science
An orbital perturbation having a period less than the period of the unperturbed orbit.
Industry:Earth science
Twelve o'clock during daylight, standard time. The instant the mean sun is over the upper branch of the standard meridian. Daylight saving noon, summer noon and war noon usually occur one hour later than standard noon.
Industry:Earth science
