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Useful Data - isle of Anglesey's Highways by Exor Configuration



Admin type

Admin unit

Area of interest

A set of network elements and/or partial network elements form an ‘area of interest’ known as a network extent.

Child group

A sub group. A term used within the context of group relations.

Datum element

See element

Datum network element

See element

Datum network type

A network the other networks are based upon. In Anglesey's case, the ESU network. A datum network type must be 'linear'. Each element on this network has to have a start node, an end node and a length.

Default region of interest

The region of interest that will be used first for a given user. Acts as the user's default selection in queries.


When a route has a break such as is resolved with a distance break.

Distance break

Points of physical discontinuity along a route, for example, at a staggered junction, may be overcome to allow ‘logical’ connectivity along the route by the addition of distance breaks. Objects (e.g. inventory items) cannot be located on them.

Element offset


Elements are the lowest level 'bits' that make up a network. Any part of a network that is not at the datum level, must be a group of some sort (either a group of sections or a group of groups). Therefore, only datum layer items can be elements, and all elements are datum layer network elements.

Element type

A prompt in the gazetteer which actually refers to any part of a network hierarchy. The available list is:
- P Groups of Groups
- G Group of Sections/Datum Elements
- S Section / Datum Element
- D Distance Break


1. See 'network extent'

2. Part of a network element from a start point to an end point within the network element.

Extent limit


A component of Highways by Exor that comprises a dialog box from which the user may move up or down a network group hierarchy to select a group or element.

This is the main way in which a region of interest is selected.

GIS theme

GIS themes allow network elements and assets to be displayed within spatial data manager.



Groups may be linear, or be non-linear groups.

When a group is linear the member elements of the group will be ‘sequenced’ to establish their relative position in the group and hence allows displacements to be calculated. Groups may also be used to describe ‘un-sequenced’ collections of elements to model such features as administrative areas.

Group hierarchy

The datum network, the groups of sections made up from that datum network and the groups of groups made up from those groups of sections.

Group of elements

A collection of elements. (Note that only datum network elements are elements, all others are groups.)

Group of groups

A group made up of items other than elements. (Note that only datum network elements are elements, all others are groups.)


Group of group hierarchy

See group hierarchy

Group of sections

A section is an element, so a group of sections is a group of elements. (Note that only datum network elements are elements, all others are groups.)

A group of sections may be linear or non-linear.


Group relation

A group of groups may be a parent to another group, an a child to a group of groups. An element may be a child of a group of sections. A group of sections is the parent of elements and may be the child of groups of groups. These are the group relationships with the parents and children being the group relations.

Group type

Group types may be linear, such as chaining network elements together (the end node of one element is the start node of the next) to form routes.

Group types may also be non-linear, such as groups representing a geographical region.


A node; a junction.


A part of the network in one layer having component parts that are contiguous such that the distance from one end can serve as a referencing method.

Linear group

A group that is linear



List of values


A network element that is part of a group of elements.


Network element

See Element

Network element group type

Network extent

A set of network elements and/or partial network elements form an ‘area of interest’. This area of interest is known as a network extent.

Network extents may contain sets of network elements from different group types or different network types.

Network extents may be used to create network groups

Network group

Network groups allow a collection of network elements to be grouped together, allowing different parts of the network to be viewed and analysed for different functional reasons.

Network group hierarchy

See group hierarchy

Network reference data

Network segment

A stretch of network which links two nodes.

Network structure

The group hierarchy

Network type

Highways by Exor can handle different types of networks. This could include, for example, road, rail, drainage, rights of way, pipelines and utility networks.



A specific junction or terminus on a network. Joined together by links known as network segments

Node point

A node's location

Node type

Exor can handle multiple networks, e.g. road, railways, drainage. Each would have a separate node network. The node types would then be 'road', 'rail', 'drain'. Different networks can share the same node type.

Non-datum network element

Another way of saying 'a group'.


The distance within a network segment from a known position

Partial group

Group types may be defined as allowing portions of network elements to be included. These group types are known as partial groups.

Partial groups may contain a mixture of elements which are either wholly contained within the group and those which are partially contained within the group.

Partial groups may also be created from a partial network extent.

Point item

An event (or asset?) on a network that occurs exactly on a node. The location of such items is recorded as being against only one of the intersecting routes although in reality it exists on all of them.

Point of equation

The system can cater for discontinuities caused by irregular measured distances of member network elements by creating a point of equation at the discontinuous node point. A point of equation may be either a gap or an overlap.

Points of equation may be created as a result of the network operations needed to model a road realignment. Points of equation may be removed by ‘rescaling’ the route. This will cause the route length values to be recalculated based on the current element lengths.

Inventory items or other database objects may not be located on a point of equation.

Region of interest

A point in the group hierarchy which represents the groups of groups, groups of sections and elements below it.

Rescaling a route


A sequence of elements; a linear group.

Route offset

The distance within a network segment from a known position

Route SLK

The length of a route – not necessarily the same as the total of the lengths of the elements that make up the route. Seemingly, only Western Australian terminology.


? “A datum element”. Since a non-datum network element is a group, a section must be the same thing as an element.

Section offset

A route offset defined as being an offset from the start of one of the subsidiary elements.


A network element or a route (linear group).


If a group is ‘linear’, member elements are connected via shared nodes or by distance breaks. The elements will be ‘sequenced’ to establish their relative position in the group and hence allows displacements to be calculated.


Straight Line Kilometre – an offset referencing system seemingly used only in Western Australia. Also, 'Straight Line Kilometreage'.

Sub class

A sub-class can be used to describe the left-hand and right-hand carriageways of a road.

Sub group

A group within a group of groups group. That is, a child group of a group of group.


When a query is run against a network extent, the results returned are called a sub-extent.

Highways by Exor's Network Manager has ESUs grouped into 4 groups. They all live on the same network type. Each has a different USRN.








Offical name

Has attributes



Road name




Unofficial name




Use for the English translation

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