- 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, ...
An instrument for measuring the Sun's angular elevation by determining the location, on a graduated staff, of the shadow of a horizontal vane. It was invented by John Davis in the 16th century and comes in two forms: one for angular elevations less than 45° and one for angular elevations of greater than 45°.
Industry:Earth science
The direction of the vertical plane containing the air base. It may be expressed as an azimuth or as a bearing.
Industry:Earth science
The part of astronomy which is concerned with the physical structure of celestial bodies their temperatures, radiation, composition, and so on. The part of astronomy which is concerned with the physical structure of celestial bodies their temperatures, radiation, composition, and so on.
Industry:Earth science
The quantity added to the period of a pendulum to account for the pendulum's departure from simple harmonic motion. The correction can be kept small by limiting the amplitude of oscillation.
Industry:Earth science
(1) Placing points along a straight line or in a common vertical plane. (2) Locating points with respect to a straight line or to a set of straight lines. The term should be used, in surveying, only for operations associated with straight lines. It is also called lineal surveying when the distance is appreciable. (3) The ground plan showing the horizontal direction and components of the center line of a highway or railroad. (4) The horizontal position of a railroad track, as described by tangents and curves. Alinement is distinguished from profile, which shows the vertical element. Alinement is also spelled alignment.
Industry:Earth science
(1) An image printed on the reverse side of a map sheet which already has printing on the obverse side. (2) The printing of such images.
Industry:Earth science
A relationship connecting the members of a time series in such a manner that the value at one instant is expressible in terms of the values at previous instances, plus a random value.
Industry:Earth science
An axis perpendicular to the longitudinal axis and generally in the plane of symmetry of the craft. It is oriented downwards or as defined by the constructor of the craft.
Industry:Earth science
(1) An angle (f) whose measure is greater than one right angle (90°, Π/2 radians, or 100 gons).
(2) An angle whose measure is greater than one right angle but less than two right angles (180°, Π radians, or 200 gons).
Industry:Earth science
The line about which the telescope or alidade of an instrument rotates when moved horizontally. For an instrument in perfect adjustment and properly leveled, this axis is vertical, passes through the center of the horizontal circle, and is perpendicular to the plane of that circle. The term standing axis is preferred.
Industry:Earth science
