Directrix

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directrix

[də′rek·triks]
(mathematics)
A fixed line used in one method of defining a conic; the distance from this line divided by the distance from a fixed point (called the focus) is the same for all points on the conic.
A curve through which a line generating a given ruled surface always passes.

Directrix

 

in artillery, a specially equipped sector of an artillery range or troop training center: targets are installed, artillery fire positions and observation points are rigged out, and so on. These sectors are designed for artillery fire (artillery directrix), tank fire (tank directrix), antiaircraft artillery fire against ground targets (antiaircraft artillery directrix), and other weapons.


Directrix

 

(of a ruled surface), a curve along which a point on a line moves such that the ruled surface is circumscribed by the motion of the line. Any curve intersecting all the generatrices may be taken as the directrix.

References in periodicals archive ?
* Presentar unas normas de calidad con el objetivo de proporcionar recomendaciones claras sobre aspectos importantes de la ERCA, basadas en la evidencia actual y en el contexto de las directrices existentes.
Estos y otros avances han dado lugar a la necesidad de revisar las directrices originales a la luz de los nuevos desarrollos.
Since we differentiated between the parabolas in [[LAMBDA]/sub.2] and [[LAMBDA]/sub.3] according to the position of their directrix, other sub-sets of [[LAMBDA]/sub.1] include parabolas with directrices that are not parallel to any one of the axes.
Le Conseil doit confirmer que les lignes directrices integrees actuelles restent valables pour la nouvelle periode 2008-2010, approuver les grandes orientations des politiques economiques et les recommandations par pays ainsi que des conclusions sur les lignes directrices pour l'emploi.