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    data : statements accepted at a given value (face value); Latin data is the plural of datum.  A large class of practically important statements are measurements or observations of physical system properties; such statements may comprise numbers, words, or images. NOTE : term data should be used in English with a plural verb, e.g. " the data are inconclusive".
    datum : a statement accepted at a given value (face value); Latin datum is neuter past participle of dare (to give), hence 'something given'. (a "given"). NOTE : term data, the plural of datum, is used more often in English.
    dB : see  decibel
   

dBa : dimensionless unit used for A-weighted sound levels, an adjusted acoustic scale.

Since the human ear is not equally sensitive to all the frequencies of sound within the entire spectrum, noise levels at maximum human sensitivity - middle A and its higher harmonics (from 2 to 4 kHz) - are factored more heavily into sound descriptions using a process called frequency weighting.

The most widely used frequency weighting is the ‘A-weighting’, which roughly corresponds to the inverse of the 40 dB (at 1 kHz) equal-loudness curve, i.e. ‘A weighting’ parallels the sensitivity of the human ear.

Frequency weighted sound levels are still expressed in decibels (dB), although symbol dBa is commonly used for A-weighted sound levels.

economics

  debt : a sum of money or other property owed by one person or organization to another; debt comes into being through the granting of credit or through raising loan capital. money
    decibel (dB) : one tenth of bell (B) : dimensionless unit used in electronics, telecommunication and acoustics to express the ratio of two magnitudes on the common logarithmic scale; if I1 and I2 are the magnitudes of two same kind signals, then the number of decibels, n, expressing their ration is

n = 10 lg(I1/I2)

Magnitude Ii could be any physical quantity characteristic for a particular signal, e.g. voltage, current or power for an electric signal, and sound pressure for loudness in acoustics. If a reference magnitude I0 is established for a particular signal, then any signal of the same kind could be referenced to it by the number of decibels. For example, the minimum detectable sound pressure level by average human ear is established as 20 µPa, and this value is set as a reference magnitude in acoustics. Then, by definition that level is 0 dB, the threshold loudness level. The sensitivity of the average human ear ranges from about 0 dB to about 140 dB, the level at which pain sets in.

botany & gardening

  decurrent : extending down the stem below from the place of insertion, as certain leaves

botany & gardening

  dehiscent : opening or splitting at maturity to discharge seeds (used of a seed pod), or opening to discharge pollen (used of an anther).

botany & gardening

  dentate : having a toothed margin or toothlike projection, as the edges of leaves.
    derived (measurement) unit : a unit of measurement derived from basic units. Each system of measurement units has certain number of units (called "basic units") defined by standards, while the rest of units is derived from the basic units.
     EXAMPLE: Electrical potential is defined as work performed per unit of electrical charge; consequently SI unit of electrical potential, V (volt) could be expressed as V = J/C, where J (joule) is SI unit of work & energy and C (coulomb) is SI unit of electrical charge. However, neither J nor C are basic units in SI, so
     V = J/C = (kg m s-2)/(A s) = kg m s-3 A-1
where kg (kilogram), m (meter), s (second) and A (ampere) are basic SI units.

basic units

SI

    device : a technical artifact, i.e. any artifact which is not a piece of art.

artifact

meteorology

  dew : atmospheric moisture that has condensed on objects near the ground, whose temperatures have fallen below the dew point temperature.

meteorology

  dew point (temperature) : a measure of atmospheric moisture : the temperature to which air must be cooled in order to reach saturation (assuming air pressure and moisture content are constant). A higher dew point (temperature) indicates more moisture present in the air. Note: sometimes written as one word : dewpoint.

 

  diaspora : any people or ethnic population forced or induced to leave their traditional ethnic homelands, being dispersed throughout other parts of the world, and the ensuing developments in their dispersal and culture; from ancient Greek *4"FB@DV (a scattering or sowing of seeds).

NOTE: originally, the term was used to refer specifically to the populations of Jews exiled from Judea in 586 BC by the Babylonians, and Jerusalem in 135 AD by the Roman Empire: "thou shalt be a diaspora in all kingdoms of the earth".

botany & gardening

  diclinous : (of a plant species, variety, etc.) unisexual flowers, having the stamens and the pistils in separate flowers, either on the same plant or on different plants; either monoecious or dioecious.
    digit : any numeral from 0 to 9, especially when forming part of an arabic number; in computing the term has a broader meaning: it includes any one of the decimal characters 0 through 9, either of the binary characters 0 or 1, and the digits 0...9, A...F used in the hexadecimal system.
    digital : a system presentation by binary numbers (a pattern of  0s and 1s) for input, processing, transmission, storage, or display, rather than a continuous spectrum of values (an analog system) or non-numeric symbols such as letters or icons. In such a system data-carrying signals are restricted to one of the two electronic or optical pulses, either logic 1 (where the pulse is present) or 0 (where the pulse is absent).
digraph : a pair of signs or symbols (two graphs), which together represent a single sound or a single linguistic unit. The English writing system employs many digraphs (for example, th, ch, sh, qu, and so on). The same two symbols may not always be interpreted as a digraph (for example, cathode versus cathouse).

botany & gardening

  dioecious : having the male and female organs in separate and distinct individuals; plants having male flowers on one plant and female on another.

botany & gardening

  dissepiment : a partition formed in an ovary by the united sides of cohering carpels, separating the inside into cells.
    dispersoid : a substance in the disperse phase, i.e. a substance consisting of particles or droplets distributed through another substance.

computing & web

  dither : a form of noise, or 'erroneous' signal or data which is intentionally added to sample data to minimize undesirable effects in digital signal processing, where a continuous range of values (or a very large set of possible discrete values) is approximated by a relatively small set of discrete symbols or integer values.

acronym

  DIY : Do It Yourself : the phrase along with its acronym fell into common usage in the 1950s in reference to various jobs that people could do in and around their houses without the the aid of paid professionals, using their own abilities and available tools and procedures. Moreover, as a subculture, DIY movement confronts consumer culture which emphasizes a purchase as the solution to all our needs.
doctrine : a principle or body of principles presented for acceptance or belief, as by a religious, political, scientific, or philosophic group.

principle

meteorology

drizzle : precipitation consisting of numerous minute droplets of water less than 0.5 mm in diameter.

botany & gardening

  drupe : any fruit consisting of an outer skin, a usually pulpy and succulent middle layer, and a hard and woody inner shell usually enclosing a single seed; fruit with a hard kernel and a fleshy pericarp, as in cherry, peach, apricot, plum, etc.

computing & web        acronym

DSL : Digital Subscriber Line : a high-bandwidth Internet connection over a telephone line.

bandwidth

 
 

UPDATED : 2007-04-27

WEBSITE  EDITOR : Krešimir J. Adamić