- 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, ...
Photographic film having sufficient dimensional stability that photographs taken with it can be used in making maps. Cartographic films are usually referred to by their trade names.
Industry:Earth science
A method of triangulation in which observations of a flare at very high altitude are made simultaneously from a number of stations of known and unknown location. The flare is usually carried aloft by a rocket or airplane and then ejected to float downward supported by a parachute. However, it may be towed by an aircraft and ignited at the desired altitude. The flare gives off light continuously. Photographs are taken of it at timed instances at each station, and the vertical and horizontal circles of the instruments are photographed at the same times. Flare triangulation has been used for extending triangulation over lines so long that the ends are not intervisible. For example, rocket borne flares were used in a stellar triangulation connecting Bermuda to the U.S.A
Industry:Earth science
That length of that part of a property which abutts a street or body of water.
Industry:Earth science
The position occupied, in a camera, by the photographic film or photographic plate.
Industry:Earth science
A diagram showing the steps to be taken in solving a problem, doing a computation or carrying out a project. The flowchart for computational purposes was originated by von Neumann and has been accepted as an essential first step in encoding an algorithm for calculation on a computer. The symbols have also been standardized.
Industry:Earth science
A pendulum consisting of a very heavy, spherical mass suspended by a very long thread or wire and set to swinging in a plane. If the site for the pendulum is carefully chosen to be free from microseisms and air currents, the pendulum will keep the plane in which it swings fixed in space while the Earth rotates under it. The plane of oscillation then appears to rotate about the point of lowest descent, with an angular speed dθ/dt given by ω sin φ', in which ω is the Earth's rate of rotation and φ' is the geocentric latitude of the point of suspension.
Industry:Earth science
An instrument for measuring the height of the tide or of a stream by measuring the height of a float on the water's surface. The float is confined within a vertical pipe or channel open, at the bottom, to the water. In the more primitive float gages, the height of the float is measured directly by reference to a graduated staff fixed to the pipe. In more advanced models, a counter weighted and graduated tape or chain attached to the float passes over a pulley geared to a recording mechanism.
Industry:Earth science
A line, usually dashed, drawn to represent the contour of the terrain. Unlike a contour line, a form line is drawn without regard to a vertical datum and without any regular vertical interval. It is sketched in on the basis of visual observations or unverified data.
Industry:Earth science
The intensity (magnitude) of the vertical component of the Earth's magnetic field, reckoned positive if the field is directed downward and negative if the field is directed upward.
Industry:Earth science
(1) A set of lines or surfaces from which angles or distances are measured to a point, and which are associated with a physical system. (2) A coordinate system associated with a physical system. (3) Any collection of points and lines made use of to set up a system of coordinates for a space. (4) A coordinate system in which measurements of distance and/or angle can be made and locations of points determined.
Industry:Earth science
