1. Session 3: Information Modelling and Information Communities
Cf data modelling.
Information Communities.

2. What is information modelling?
A representation of concepts, relationships, rules, constraints and operations to specify data semantics for a chosen domain of discourse.
Can provide a shareable, stable set of information concepts in the domain.

3. Information Modelling and Data Modelling
Information modelling describes concepts, not attached to a particular implementation.
Data models are mappings of the information model to an implementation (UML, ER diagrams, XML Schemas).

4. But having said that...
We often create geospatial information models with UML modelling tools (e.g. Enterprise Architect).
But still modelled in a way that is less attached to implementation.
More conceptual than logical or physical, but quite separate from implementation.

5. Harmonised Information Modelling
A group of people come together to agree on a particular information model in a domain or group of related domains.
Usually so they can share, exchange and integrate data from different sources.

6. ICSM Harmonised Data Model
Information Committee on Surveying and Mapping.
Australia and New Zealand.
Started in late 90s, latest version 2008
Created from jurisdiction models.

7. ICSM HDM The Model Covers:
Rights, Restrictions, Responsibilities (cadastre);
Topography;
Place names;
Street address;
Geodesy and Surveying;
Admin areas.

9. INSPIRE European Directive
Infrastructure for Spatial Information in Europe.
To support data sharing for environmental management.
Very large exercise.

10. INSPIRE The Model Covers 34 Themes.
Annex I complete, Annexes II and III starting.
In Annex I: Cadastre, Admin Areas, Addresses, Transport, Hydrography, Protected Sites.
Standards-based (ISO, OGC).
Not just model, DPS.

12. Advantages of Information Modelling
Enables discussion.
Creates an agreed model that jurisdictions can map to (not usually suitable for production systems).
Provides a basis for sharing, discovery, etc.
Beginning of semantics (more later)...

13. Disadvantages of Information Modelling
A lot of effort.
Sometimes the least common denominator, loses the strengths of individual models.
Two strategies:
Include everything – then no one can provide everything.
Include only common elements – simple but basic.
Can be controlled by a dominant individual.

14. Standards Used for Geospatial Information Modelling
Most commonly Unified Modelling Language (UML).
Sometimes generate GML from the UML diagram (automatic tools available).

15. Unified Modelling Language (UML)
Very comprehensive graphical modelling language.
Object based.
Models for many things (class, package, processes).
Originally for software engineering.

16. UML and Geospatial Modelling
Used almost exclusively for geospatial information modelling:
class and package models;
almost always used with Enterprise Architect.
HollowWorld environment available with all the geospatial ISO/OGC standards.

17. Geography Markup Language (GML)
An XML grammar written in XML Schema.
For geographic information.
Very comprehensive:
Geometry, topology, temporality;
0, 1, 2 and 3 dimensional features;
Everything you can imagine!
Uses various ISO standards.
You can use the Simple Features Profile.

19. What is a Geospatial Information Community?
A group of people who share a similar worldview in a domain.
Often related to discipline groups.
Probably it is possible for them to create an information model of their domain.
Also an important concept in semantics...

20. Discussion Geospatial information communities in your organisation?
Differences between them?
Information modelling activities?