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wrfaca configuration, surface materials, wtiac4
drainage, and abslacla analysis. The varbus
data base pmducta cmwrisad of DTAD are
used In Ienain analysis, largeli~, battlefield
modeling and simulation.
Dlgltal Terreln Elevation Data (DTED)—A
uniform matrix of terrain elevatbn vafuee
pmducad by DMA. DTED provides basic
quantitative data for au military trainii,
planning, and opamflng systems requiring
Ierrain elevation, abpe, andor auriace
roughness inlormstion. Level 2 post spacing is
1 arc eeoond Iaftiudinalfy, Level 1 PSI spacing
Is 3 arc second Iatifudlnallfi for both, Iongiktdlnal
spacing varies wills Ialilude.
Dlgltal Terrain Matrix (DTM)-A regular
grid of geographic or model coordinates fhaf is
fhe orimaw outcut of Ihe collection process. Tha
data contained “fherain consists of elevation
data raferred to a grid (row and mlumn
occurrences) systam. Grid spacing may vary
according lo surlace model accuracy
requirements.
dlgltal data basa (oli.llne)-A digital dsla
base maintained in a common format fhst
supperts diftarant user syslems, e.g., simulator
or weapon systems Normally the data must be
transferred belore it can be used by a specific
user system. This term is commonly expressed
as the off-line dafa base.
digital data baae (on-llne)-A digital data
base In the format needed by a user syslam,
e.g., simulator or weapon system, and which
can be badetf into the user system. This term is
commonty relerred 10 as Ihe on-fine data base.
dlgltal data-These are data represented In
alphanumeric Iormst readable by a computer.
dlgftal feature data—1. (cullural data) Manmada,
natural and landscape features in digital
Iorm, data in discrete digiial (numerical) Iofi,
Incbdlng all man-made features on the Easfh’s
surface, e.g., lines of communication, built-up
araas (cifiea), transmission fines and Iardmsrk
structures. 2. (hydrogrephic data) Data derived
from Ihe meawremanl and description of
physical features of the oceans, takes, rfvera
and other WSfam, and their adpinlng coaflal
araas (with particular refarence to navigational
usage) In dlgffal form. 3. (landscape feature
data) Data of all natural Ieaturas and man’s
afferalbn to fhose features, e.g., lake wlfh dam,
agricultural features, etc., in digital form. 4.
MIL-HDBK-850
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(natural feature data) Naluml features on the
Earth’s wdace which are not rwrn-msde, e,g.
vegetation, water bodies, desert, etc. in dlglfaf
form.
digital Image-An image digital format
oMainad by parlitbning the area 01 the Image
into a finite fwo-dimensional array of uniformly
shaped, rrwtuafly exclusive regions called
plxela (pbfura etanwnts), arxi assigning a
descriptive tone or shade lo each such epafial
region.
dlglfaf map-1. A map expressed and stored
in dgltal form. 2. A repreaentafion In diglfal
form, diicrete points on Ihe Earth’s surlaca. Also
called numarlcal map.
dlgltal eynthaalzed data—Data derived
from fhe analysis o! IWO or more different IypeS
of dafa wch ae Digital Terrsin Elevation Data,
D@ilal Natural Feature Data, and Dighaf Cultural
Feature Data, An axample Is the derivaffon of
data which can assess the effects of soil types,
vegetation slope, drainage and microrafief on
cross-coum~ movemem 01 vahbfas.
dlgftal synlhagc- dats-Dafa in numerical
format Ihat describes either totally or parfiatiy
fictitious information generated trom lower
resolufion?frequency input.
digital terrain model (DTM)-A statistical
rapresenlalion 01 tha cominuous wsiace of the
ground by a large number 01 seleclsrd points
with known rectangular coordinates In an
arbitrary coordinate Iiald. See also Dlgltal
Elevatlon Model.
Digltlzed/Dlgftal Pofnt Posltfonlng Data
Base (DPPDB)-Tha digitized PPDB Is a
rastar-scanned digital randffion of the currant
anabg PPDB product. DMA Is investigating the
petential for a completely digital PPDB product.
dihedral ang Ie—lhe angle between two
inlersecfing planes.
dimensional atablllfy—1. Ability lo maintain
size. 2. Resistance to dimensbnal changes
caused by changes in moiafure content and
{emperafura.
DIN—The German Industrial .Starrdad
(Deutsche lndustrie-Norm), a Europaan systam
of standardization for mechanical, engineering,
and scientific manufactured producfs. In MC&G,
the most nofable application is the