Glossary
D/A
Database
Collection of interrelated data in order to handle and maintain a large amount of data.
Database Model
A model to access the database. There are four database models; hierarchical, network, relational and object-oriented model.
Data Capture
A series of operations to acquire, transform and edit data into a readable format by computer.
Data Model
A set of guidelines to convert the real world to the digitally represented form consisting geometric data and attributes. There are vector and raster models.
DBMS
Database Management System provides a number of functions which retrieve, edit, manipulate and analyze spatial and non-spatial data.
DEM
Digital elevation model by which continuous surface such as terrain surface can be represented. DEM is used to interpolate elevation at arbitrary location using limited number of three dimensional terrain points.
Digital Photogrammetry
Photogrammetry with use of digital image data that are rasterized from analog photographs or acquired directly with digital camera.
Distributed System
Computer system with a server and clients (or terminals), that are connected by network such as LAN (local area network).
Dot Printer
An image output device to produce a raster image with small dots (black and white, or color) based on elector static theory. The tone or texture of image is produced by dot matrix.
DTM
Digital terrain model is to represent or extract topographic information from the DEM. DTM includes contour lines, profile, drainage system, slope and aspect, shade and shadow, slope stability etc.