- 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 method of making lithographic plates by etching the design slightly into the surface of the plate.
Industry:Earth science
Any factor which must be taken into consideration when calculating the correct time interval for exposure. Among the important exposure factors are the relative aperture of the lens system, type of photographic film used, reflecting power of the object to be photographed, season of the year, time of day, color of the light, geographical location, altitude at which photograph is being taken (if an aerial photograph) and atmospheric conditions.
Industry:Earth science
(1) The difference between the measured value of a quantity and the theoretical or defined value of that quantity: ε(error) ≡ y (measured) - y (theoretical). (2) The difference between an observed or calculated value of a quantity and the ideal or true value of that quantity. Logically, definitions (1) and (2) are distinctly different. In practice, they are equivalent except for the second definition's allowing calculated values to be used instead of measured values. (3) The difference between an approximate number and the correct number. (4) The difference between the theoretical or defined value of a quantity and the measured value of that quantity: ε (error) ≡ y (theoretical) - y (measured). This definition differs from the first definition only in changing the sign of the error.
Industry:Earth science
An error whose amplitude and direction vary systematically with time.
Industry:Earth science
(1) A very large error. The usual implication is that the error was made by a person. If this is to be made explicit, the error is termed a blunder. (2) An error which is the result of carelessness or a mistake.
Industry:Earth science
(1) A voluntary surrender of rights or claims. (2) The act of divesting oneself of that which was previously as one's own, or renouncing it. In this sense, it is the opposite of appropriation.
Industry:Earth science
A survey made to add to an existing, partial survey. An extension survey does not, however, complete a survey of boundaries, townships, sections or subdivisions thereof.
Industry:Earth science
An extensive fault in which the movement is parallel to the horizontal direction of the fault and the surface of the fault is steeply inclined.
Industry:Earth science
The difference between the measured value of a quantity and a value adopted as representing the ideal or true value of that quantity. Errors of observation are composed of either one or both of two general classes of error: accidental errors and systematic errors. Constant errors are sometimes placed in a third class but are more often included among the systematic errors as they should be. Errors of observation are also classified according to their origin as external errors, instrumental errors, and personal errors. The algebraic sign of the error of observation is determined from the equation: error of observation = measured value adopted (ideal) value. The term error of observation is dropping out of use and is being replaced by measurement error.
Industry:Earth science
A method of measuring the time at which a stellar image crosses a particular line in a reticle, by counting off the seconds or half seconds to oneself while observing the passage. Counting is started by looking at the chronometer and counting in cadence with its ticks. Attention is then diverted to the telescope but counting is continued. The interval from the tick just before crossing to the moment of crossing is estimated, and the times of the ticks themselves remembered. The time of crossing is calculated from these values.
Industry:Earth science
