- 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, ...
An image in which each point corresponds to a separate point of the object, and each point of the object corresponds to just one point in the image.
Industry:Earth science
Sequential analysis applied to problems of mechanics or electrical engineering. In particular, the method of least squares applied to data as they arrive singly or in sets, i.e., sequentially, rather than to all the data at once.
Industry:Earth science
(1) A systematic error caused by misplacement of an index mark or zero mark on an instrument having a scale or vernier, so that the instrument gives a non zero reading when it should give a reading of zero. This is a constant error. (2) The distance upwards (or downwards) from the foot of a leveling rod (the lowest horizontal surface) to the nominal origin (theoretical zero) of the scale.
Industry:Earth science
One of the rays connecting each of a set of corresponding image points with its particular perspective center.
Industry:Earth science
The refractive index of the atmosphere, modified mathematically so that when its gradient is applied to an equation for the path taken by energy over a (hypothetically) flat Earth, it yields a path substantially equivalent to that followed by the energy over the true, curved Earth. A formula frequently used for the modified index n' is n' = (n + h/R), in which n is the actual refractive index, h is the difference between the elevations of emitter and receiver and R is an average radius of the Earth.
Industry:Earth science
The science of inferring the physical dimensions of objects from measurements made on images of the objects. Also written iconogrammetry. Ikonogrammetry includes photogrammetry, which involves measurements on photographs; radargrammetry, which involves measurements on images created on a cathode ray tube by radio waves; and X-ray photogrammetry. However, photogrammetry is often used instead of the more proper term ikonogrammetry. The definitions given for various kinds of photography can be transformed to the corresponding kinds of ikonogrammetry by substituting image for photo-graph and electromagnetic radiation or particles for light, where appropriate.
Industry:Earth science
The quantity (5m/2) (1 + 25(1 - 3C/2Ma²)²/4) characterizing the shape of a body of mass M in hydrostatic equilibrium and rotating at the rate ω. The equatorial diameter is 2a, the moment of inertia about the least axis is C and m is the quantity ω²a3/GM, in which G is the gravitational constant.
Industry:Earth science
The organization established in 1962 to take over the work of the International Latitude Service (I.L.S.) and to include, with the work of I.L.S.'s observatories, data from a large number of other observatories also engaged in determining latitude. A great variety of instruments are used. The principal types are the visual zenith telescope, the photographic zenith telescope and the Danjon astrolabe.
Industry:Earth science
The study of the interference occurring when two separate wavefronts (i.e., beams) of radiation are combined. Interferometry involving electromagnetic radiation is more important to geodesy than that involving sound waves; that involving sound waves is of sole interest in hydrography and seismology.
Industry:Earth science
