Fr.: température de bruit
A means for specifying the noise generated as unwanted → electromagnetic radiation in a receiver system or one of its components. It is usually measured in terms of the equivalent temperature in a → Rayleigh-Jeans spectrum. Noise temperature is used mainly in radio astronomy.
Fr.: voltage de bruit
Fluctuations of electric potential in a physical system due to spontaneous disturbances in the system.
tavân-e ham-arz-e nufé
Fr.: puissance équivalente de bruit
A measure of the sensitivity of an electronic detector, defined as the power input to the detector that will create a signal to noise ratio of one for an integration time of half a second.
A set or system of names or terms assigned to objects or items in a particular science or art.
From Fr. nomenclature, from L. nomenclatura "calling of names," from nomenclator, variant of nomenculator "one who announces names, namer," from nomen, → name, + calator "caller," from calare "to call."
Nâmgozâri, from nâm, → name, + gozâri, verbal noun of gozâštan "to place, put; to allow, let," related to gozaštan "to pass, proceed, go over;" Mid.Pers. vitar- "to let pass, lead; to pass;" O.Pers. vitar- "to go across," viytarrayam "I put across;" Av. tar- "to cross over," vī-tərəta- "taken away, isolated;" ultimately Proto-Ir. *ui-tar-.
1) Of, pertaining to, or constituting a name or names, a noun or nouns.
From L. nominalis "pertaining to a name or names," from nomen "name," cognate with Pers. nâm, as below.
Nâmin, from nâm, → name, + adj. suffix -in.
nominal focal length
derâzâ-ye kânuni-ye nâmin
Fr.: distance focale nominale
An approximate value of the → focal length, used for the classification of lenses, mirrors, or cameras, as opposed to the measured one.
Fr.: valeur nominale
The assigned, specified, or intended value of a quantity.
A prefix meaning "not."
From O.Fr. non-, from L. non "not," from Old L. noenum "not one;" in some cases perhaps from M.E. non "not" (adj.), from O.E. nan.
Nâ- "no, not," variants na, ni, ma- (prohibitive) "not;" from Mid.Pers. nê, ma "no, not;" O.Pers. naiy, nai "not;" Av. nôit, naē "not;" cf. Skt. ná "not;" cf. L. ne-, in-, un-; Gk. ni; Lith. nè; O.C.S. ne "not;" PIE *ne-.
Fr.: fonction non algébrique
A → transcendental function. Examples are: exponential, logarithmic, and trigonometric functions.
non-baryonic dark matter
mâde-ye siyâh-e nâbâriyoni
Fr.: matière noire non-baryonique
mâdde-ye nâbâriyoni (#)
Fr.: matière non-baryonique
Matter that, unlike the ordinary matter, is not made of baryons (including the neutrons and protons). It is proposed as a possible constituent of dark matter.
tâbeš-e nâhamdus (#)
Fr.: rayonnement incohrént
Radiation having waves that are out of phase in space and/or time; radiation which is not → coherent.
Fr.: non contingent
Fr.: milieu non dispersif
A medium in which the → phase velocity is independent of frequency.
hendese-ye nâ-oqlidosi (#)
Fr.: géométrie non-euclidienne
Any of several geometries which do not follow the postulates and results of Euclidean geometry. For example, in a non-Euclidean geometry through a point several lines can be drawn parallel to another line. Or, the sum of the interior angles of a triangle differs from 180 degrees. According to Einstein's general relativity theory, gravity distorts space into a non-Euclidean geometry.
non-hierarchical multiple system
râžmân-e bastâyi-ye nâpâygâni
Fr.: système multiple non hiérarchique
cârcub-e nâlaxtinâk, ~ nâlaxtimand
Fr.: référentiel non inertiel, ~ non galiléen
Any frame of reference in which the law of inertia does not apply, such as in accelerating and rotating frames. For example, the Earth is a non-inertial frame because it is rotating about its axis. But the rotation is so slow that the associated acceleration is negligible compared to other accelerations commonly encountered in everyday life. However, the non-inertial nature of the Earth appears in, e.g., the → Coriolis effect. → inertial reference frame.
Fr.: non ionisé
Not ionized, → neutral.
non-local thermodynamic equilibrium (NLTE)
tarâzmandi-ye garmâtavânik-e nâmahali
Fr.: hors équilibre thermodynamique local
A physical condition in which the assumption of the → local thermodynamic equilibrium does not hold.
Fr.: matière non lumineuse
Not ordinary matter. Same as → dark matter.