- 行业: Earth science
- Number of terms: 93452
- Number of blossaries: 0
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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, ...
The art or science of determining depths of oceanic or other deep waters.
Industry:Earth science
Of, or pertaining to, astronomy. It is completely equivalent to the form astronomical. Although Merriam-Webster (2nd edition) gives precedence to astronomical, it is the compiler's experience that surveyors use astronomic while astronomers prefer astronomical.
Industry:Earth science
The process of obtaining differences of elevation by means of observed vertical angles together with lengths of lines. In geodesy, vertical angulation is called trigonometric leveling.
Industry:Earth science
Making observations, in leveling, in such a way that distances to the two leveling rods are approximately equal. Also referred to as balancing lines of sight and balancing backsight and foresight distances. The difference in distances is sometimes called the imbalance.
Industry:Earth science
A horizontally held bar carrying two easily visible marks a fixed, known distance apart, and used for determining the distance from an observer to the bar by means of the angle subtended at the observer by the marks on the bar. The marks are often placed on fittings mounted at the ends of the bar and connected by invar wires under slight but constant tension. This counteracts the effect of temperature on the distance between marks. In use, the subtense bar is mounted horizontally on a tripod and centered over the mark to which distance is to be determined. The angle subtended at the observing instrument is measured and automatically converted by the instrument to distance. The observer reads off the distance, not the subtended angle.
Industry:Earth science
An azimuth determined by solving the navigational triangle with altitude, declination and latitude given.
Industry:Earth science
The difference between the celestial longitudes of the Sun and a planet, as observed from the Earth.
Industry:Earth science
A pure silver used in the 1938 redetermination of atomic weights. It is specified as the silver to be used in the chemical determination of chlorinity of sea water.
Industry:Earth science
The technique or procedure developed by R. Fisher for separating the total variance of a sample into a sum of variances traceable to specific sources.
Industry:Earth science
