1 - NGA

.. .. MIL-HDBK-850
D log E curve-See ctrsrac!erlatlc curve.
dally ●berratlorr-See diurnal abermtlon.
deny lnequellty-See diurnal Inaquellty.
denger Ilne-1. A lime drawn on e charl to
indk.ate the Iirrrffs of safe navi@on for e vesset
of epactiic draft. 2. A tine of smaU dots used to
drew the navigetots aftenfiin to a danger which
WOufd not stand wt dearty enough if it wara
represented on the chart solely by epaciflc
symbols.
Dete ExtractIon Segmen! (DE/S)—
Segmenl of DMAs Digital Production Sy61am
which will provfde the capabllify to extract terrain
elevatbn and feature data horn stereo aoff copy
(dgltal) imagery. Terrain data will be estracfed
aufornat!cally using digilal correlation techniques
as well as Interactively by an operator. Featura
data will be extracted interactively utilizing
aUIOMatiC feature recognition techniques,
Digital image processing techniques will eid the
erralysl in tha ime,rpretation and extract”km of
feetures. See also Dlgltal Production
System; MARK .95; MARK 90.
Date Integretlon Sagmen! [Dl/S)—
Segment of DMAs DPS which will provide
Suppon tor DMA planning and production
management activities as well aa an automated
management system for source library holdings
and other data bases. Aaslgnmenl generation,
achedufing took, and production reporting
capabilities will be available to all Ievek of DMA
management. See elso Dlgltal ProductIon
Syatam; MARK 90.
Date Services Segment (DS/S)—Segmenl
of DMAs Dtgital ProdurMon System which will
provide data management arid communication
services for the MARK 90 phase. 11will also
provide for data basa menagemerrf and
archiving of digital data as well as much of the
management data required for operation of the
DPS. This aagment will have the cepabiiiiy to
store one milfiin gigabits 01 data. It is one of
the fargeat data bases In existence. In ac!diiion
to Ifs other furcsions, Data Servkas will provida
an ehscfronio txrmrrwnlcation network for [he
OPS. Sae also Dlgltal ProductIon
System; MARK 90.
D
Ltata ECqUISdtlWI stetlon-A ground station
uead tor parformlng the various functions
necessary to control satalUle oparatkrns and to
obtain data trom the aatelliie.
deta bfsnkhlemrchy-A formalized structure
which provides for I he o~anization of data at
various quantitative levels; e.g., data bank, data
base, file, record, field (elamenf); character, bit.
data base system-A collection of peopte,
machines, and methods organized to
accorr$dish all of the fundiorrs of a dSta bSSe.
data baea-1. A set of data, part or the
whole of anothar sef of data, and wnsisting of
at least one file that is suffkierrf tor a givan
purpose or for a given data processing SySteITt.
2. A coflecflon of data fundarnenfal to 8 system.
3. (digital mapping) An organized set of
evalualad MC&G data stored In either graphic,
textual, or digital form. A data base may contain
one file of data, e.g. terrain elevatiin data, or
several da!a files, e.g., cartographic, gaodetic,
There are three kincs of data bases: 1) those
that contain irdormation eboti Information; 2)
those thal contain information shut data: and
3) those that contain the actual data.
data category (layar)-Rafars 10 data
having similar characteristics baing contained in
tha same data set, eg., roads, rivers. Usually
information contained in one data category is
related and is designad 10 be used with other
categories.
deta chamber—The porf”mn of a cartographic
aerial camera where ancillary date k recwded
abng the film margins. Data usually includas
flme, attitude, frame number, and othar
information required for idenfifkafion arxf
carefetbn purposes. It may tnclude a character
data generator block and ezfansive binary
coded inforrnafion to include aircraft positbn
and camera orianfation data.
data dlctlonaW-Repository of Information
abouf the dafinltion, structure, and usage of
data. It does not comain the actual data.
data elament-(JCS) A basic unff of
information heving a uniqua meaning and
subcalagorias (data items) 01 dktirwt unffs of
values.
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