Fr.: modèle de données
An abstract entity that describes the structure of → database by including the formal description of the information system used in the database.
data number (DN)
Unit of the analog-to-digital conversion system of a CCD apparatus. For example a 16 bit system may use a maximum of 65536 DN. The acronym ADU, for analog-to-digital unit, is also used.
dâdé âmâyi (#)
Fr.: traitement de données
Systematic operations on data, such as handling, merging, sorting, and computing.
dâdé âmâ (#)
Fr.: processeur de donées
A machine for handling data in → data processing.
Fr.: réduction de données
The process of converting crude observational data into usable information for scientific interpretation, by correcting, rearranging, ordering, and simplifying.
Fr.: structure de données
A → method or → format for organizing and storing data. Any data structure is designed to organize data to suit a specific purpose so that it can be accessed and worked with in appropriate ways. In computer programming, a data structure may be selected or designed to store data for the purpose of working on it with various algorithms.
pâygâh-e dâdehâ (#)
Fr.: base de données
A combined and coordinated set of data that supplies information for a specific purpose in a variety of forms.
A particular day, month, and year at which some event happened or will happen.
Date, from O.Fr. date, from M.L. data, from datus "given," p.p. of dare "to give, grant, offer," from PIE base *do- "to give" (cf. Pers. dâdan "to give," as below). The Roman convention of closing a document by writing "given" and the day and month (meaning "given to messenger") led to data becoming a term for "the time stated."
Gâhdâd, from gâh "time"
(Mid.Pers. gâh, gâs "time;" O.Pers. gāθu-;
Av. gātav-, gātu- "place, throne, spot;"
cf. Skt. gâtu- "going, motion; free space for moving; place of abode;"
PIE *gwem- "to go, come") + dâd "given," as in Latin;
p.p. of dâdan "to give"
(Mid.Pers. dâdan "to give," O.Pers./Av. dā-
"to give, grant, yield," Av. dadāiti "he gives,"
Skt. dadáti "he gives," Gk. didomi
"I give;" akin to L. data, as above); cf. Mid.Pers., Mod.Pers. dâd
"year, age, period of life," Lori, Laki dâ(d) "age," homdâ
"of equal age."
senn yâbi (#)
Use of appropriate techniques to estimate the age of geological specimens or astronomical objects such as meteorites.
Verbal noun of date, from O.Fr. date, from M.L. → data.
Sen yâbi, from Ar. sen "age" + yâbi verbal noun of yâftan, yâbidan "to find, discover; to obtain, acquire," Mid.Pers. ayâftan, ayâpênitan "to reach, attain," Manichean Mid.Pers. 'y'b "to attain," Parthian, Sogdian (+ *pati-) pty'b "to reach, obtain," Av. ap- "to reach, overtake," apayeiti "achieved, reached," Skt. âp- "to reach, gain," âpnoti "reaches, gains," Gk. hapto, haptomai "to touch, cling to, adhere to," L. apiscor "touch, reach;" PIE base *ap- "to take, reach."
1) dâdé (#); 2) dâdebon; 3) farâzbon
1) A single piece of information, as a fact, statistic, or code.
L. datum "given," neuter p.p. of dare "to give, offer," cf. Av. and O.Pers. dā- "to give, grant, yield," Av. dadāiti "he gives," Skt. dadáti "he gives," Gk. didomi "I give," PIE base *do- "to give."
Dâdé "given," p.p. of dâdan "to give,"
Mid.Pers. dâdan "to give," O.Pers./Av. dā- "to give, grant,
yield," akin to L. data, as above.
Fr.: noyau fils
From M.E. doughter, O.E. dohtor, from P.Gmc. *dochter (Ger. Tochter), from PIE *dhug(h)əter-; cf. Av. dugədar-, duγdar-, Mod.Pers. doxtar, Skt. duhitár-, Gk. thygater, Arm. dowstr, Lith. dukte.
Doxtar, from Mid.Pers. duxtar, duxt, O.Pers. *duxçi-, Av. dugədar-, duγdar-, cognate with daughter, as above.
Fr.: noyau fils
Fr.: expérience de Davisson-Germer
The experiment carried out in 1927 that confirmed the → de Broglie hypothesis as to the → wave nature of the → electron. It showed that electrons scattering off crystals form a → diffraction pattern. The experimental setup consisted of a → nickle chloride → crystal as → target, an electron gun, and a → detector placed on a graduated circular scale. The intensity of the reflected electrons was measured as a function of angle and electron energy. The observations showed a strong intensity peak at a certain angle. The nickel crystal acted as a → diffraction grating. → Constructive interference occurred at a particular angle, where the peak intensity was observed in accord with → Bragg's law. Interestingly, the intent of the initial experiment was was not to confirm the de Broglie hypothesis. In fact, the discovery was made by accident.
Carried out by American physicists Clinton Davisson (1881-1958) and Lester Germer (1896-1971); → experiment.
pegâh (#), sepidedam (#), bâmdâd (#)
Fr.: aube, point du jour, aurore
M.E. dawen (v.), from O.E. dagung, from dagian "to become day," from root of dæg→ day.
Pegâh, from Mid.Pers. pa gâh, from pa "to; for; in; on; with;
by; according to," O.Pers. upā,
Av. upa "toward, with, on, in, in the time of"
(cf. Skt. úpa "toward, together with, under, near to, on,"
Gk. hypo "under, below," L. sub "under," Ger. auf, E. up;
PIE *upo "under, up from under, over") + gâh "time,"
O.Pers. gāθu-, Av. gātav-, gātu- "place, throne,
spot" (Skt. gátu- "going, motion; free space for moving; place of abode,"
PIE *gwem- "to go, come").
NASA's mission to explore the two largest objects in the → asteroid belt, the asteroid Vesta and the → dawarf planet Ceres, gathering data relating to their composition, internal structure, density and shape. Launched in September 2007, Dawn entered the orbit of → Vesta in July 2011 and spent 16 months there before leaving for → Ceres. It entered Ceres orbit on March 6, 2015. The Dawn spacecraft is made of aluminium and graphite composite, it has a dry mass of 747.1 kg and a mass of 1217.7 kg when fully fuelled prior to launch. The spacecraft is a box-shaped design measuring 1.64m × 1.27m × 1.77m.
The length of time it takes Earth (or a planet) to rotate once on its axis relative to some external reference. The day is measured in several ways, depending on this reference, → sidereal day; → solar day; → mean solar day.
M.E., from O.E. dæg (cf. Ger. Tag, Swedish and Danish dag "day"), from PIE base *dhegh- "to burn." Not related to L. dies "day" (from *dyeu- "to shine," → diurnal), but rather to Av. dag- "to burn," dažaiti "burns," Mod.Pers. dâq "hot," Skt. dah- "to burn," dáhati, Gk. tephra "ash," L. fovere "to boil," Albanian djeg "to burn," Russ. žeč' "to burn," Lith. dagas "hot season," degti "to burn," O.Prus. dagis "summer."
Ruz "day," from Mid.Pers. rôc, O.Pers. raucah-, Av. raocah- "light, luminous; daylight," Skt. roka- "brightness, light," cognate with Gk. leukos "white, clear," L. lux "light" (also lumen, luna), PIE base *leuk- "light, brightness". The Persian words rowšan "bright, clear," foruq "light," and afruxtan "to light, kindle" also belong to this family, as well as the E. light, Ger. Licht, and Fr. lumière.
Fr.: météore de jour
daylight saving time
vaxt-e nur anduzi, vaqt-e ~
Fr.: heure d'été
A system of adjusting the official local time in some countries in order to provide a better match between the hours of daylight and the active hours of work and school. The "saved" daylight is spent on evening activities which get more daylight, rather than being "wasted" while people sleep past dawn. Although known also as summer time, it includes the spring season and nearly half of autumn.
→ day; → light; saving, from save, from O.Fr. sauver, from L.L. salvare "to secure," from L. salvus "safe," PIE *solwos, from base *sol- "whole" (cf. O.Pers. haruva-, Av. haurva- "whole, intact," Mod.Pers. har "every, all; any," Skt. sarva- "whole, entire," Gk. holos "whole"); → time.
Vaxt, written vaqt
Fr.: temps de jour
The time interval when the Sun is above the horizon for a given position.
Ruzhangâm, from ruz→ day + hangâm "time, hour, season," Mid.Pers. hangâm "time, epoch, season," Av. ham-gam- "to meet together," from ham- "together," → com- + gam- "to come; to go," jamaiti "goes," O.Pers. gam- "to come; to go," Mod.Pers. âmadan "to come," Skt. gamati "goes," Gk. bainein "to go, walk, step," L. venire "to come," Tocharian A käm- "to come," O.H.G. queman "to come," E. come; PIE root *gwem- "to go, come."
Fr.: lacune DB
The observed absence of helium white dwarfs with temperatures between 45,000 and 27,000 K. A possible explanation lies in the chemical evolution of white dwarfs. Four processes can change the structure of a white dwarf: gravitational settling, interstellar medium accretion, mass loss, and subsurface convective mixing.