LIST OF ACRONYMS

CAD : Computer-assisted design
DRS : Data with spatial references
MRC : Regional municipality of County
DBMS: Database management system
GIS : Geographical Information System
SIRS: Spatial References Information System
SIT : Territory Information System
SIURS: Urban information system to space reference
TI : Information technology
MRN : Ministry for the Natural resources
SDA: System on Administrative Cuttings of Quebec
UTM: Cartographic projection Universal Transverse Mercator
MTM: Cartographic projection Transverse Mercator Modified
BDTQ: Topographic Database of Quebec
BDAP: Precision Agriculture Database


Glossary

Arc
Succession of right-hand side segments connected to each other. An arc is also defined as the ordered list of the pairs of co-ordinates which are used to build a line.

Attribute
Characteristic of a geometrical entity, described by numbers or characters and stored in a table.

Sweeping
Process of creation of matric data (images) with equipment called sweeping optics.

Geographical co-ordinates
Values expressing the latitude and the longitude of a point. The latitude (symbolized by the letter J) measurement angles in the Southern Northern direction, starting from the equator. Longitude (symbolized by the letter L) measurement angles in the East-West direction, starting from a prime meridian.

Cover
Lay down information specific to the system Arc-information. The cover is the basic unit of the space organization of the geographical entities. The cover contains only one type of geometrical entity (not, line or polygon) for a topic or part of a topic.

Datum
Frame of reference made up of the constants which make possible to calculate in a univocal way the co-ordinates of any point on Earth.

Double precision
Level of precision of the data based on a high number of decimals which can be recorded for each co-ordinate. The double precision depends on the system used; in Arc-information, the double precision gives 13 digits after the decimal point.

Geographical entity
Modeling of a phenomenon located on the surface of the Earth.

Geometrical entity
Elementary geometrical form (not, line or polygon) which gives the localization and the shape of the objects represented.

Identifier
Does single code allotted to each occurrence of an entity, the identifier answer the question "which? " and allows to distinguish each individual from a data base.

Code
Code allotted to a class of entity and which defines the nature of the phenomenon represented. Does the code answer the question "what? ".

INFO
System of management of the descriptive data of the system Arc-information to record and handle the tables of the attributes.

Land parcelling out System of division and classification landed property. In Quebec, there are two systems: primitive land surveying and the land register. Primitive land surveying was founded to distribute the grounds to the colonists. In 1860, the land register was created for the recording of the private properties. Currently the two systems exist together : primitive land surveying is mainly used to indicate the public grounds and the land register to indicate the private grounds.

Node
Not located at the end of an arc. A node is a particular vertex.
In topology, a node is defined in a more restrictive way by the point of intersection of at least three arcs.

Node during (dangling node)
End of an arc which is not connected to another arc.

Pixel
Acronym for "picture element". Smaller information, of square form, an image or a chart in matric form. The dimension of the pixel defines the picture resolution.

Dot
A simple pair of co-ordinates which represents a geographical entity.

Dot control
Dot control which allows the setting in register of the charts or the images to be digitized compared to the selected frame of reference of reference.

Polygon
Surface delimited by a succession of perfectly connected arcs. In topology, the polygons are mutually exclusive surfaces.

Cartographic projection *
Transposition of a portion of the ellipsoid of reference representing terrestrial surface, on a plane surface, using a mathematical model.

Pseudo-node
Node which connects only two arcs having the same values of attributes or node located at the end of an arc which is closed again on itself.

Topic
Collection of geographical entities gathered according to a logic specific to the applicability.

Tile
Geographical unit of cutting following which the geographical data are subdivided in space.

Topology
Connect mathematics treating of the relations of vicinity which are established between geometrical figures, relations which are not deteriorated by the deformation of the figures.

Vertex (top)
Pair of co-ordinates of the ends of the segments of right-hand side which make an arc.