The document discusses the development of a PostgreSQL extension for capturing and analyzing dynamic phenomena, specifically in the context of geoinformatics and spatio-temporal analyses. It emphasizes the need for unified modeling in the time dimension through the implementation of ISO 19108 standards, which include explicit modeling of temporal objects and operations. Additionally, it outlines the potential applications of these techniques, such as feature successions and enhanced geoinformatics functionalities.

1. Providing methods for
Peter Broßeit
the capture and analysis of
dynamic phenomena through
a PostgreSQL extension

2. Is the time still an issue in geoinformatics?
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3. Is the time still an issue in geoinformatics?
Which land use features are the predecessors of a
particular nature reserve?
Capabilities for spatio-temporal analyses in today‘s GIS are at best
vestigial
Data storage through existing data types
–> No unified modelling in the time dimension
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4. Concept
• Modelling the valid time dimension with
one user defined data type
• Instants, periods of time and temporal complexes
• Based on ISO19108
Actual Purpose:
Unified modelling -> homogeneous queries
Explicit modelling of periods of time and temporal
complexes
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5. Temporal Schema - ISO19108
Schema to describe the temporal characteristics
of geographic information
Feature attributes, feature operations & feature
associations
• Temporal objects
• Various reference systems
• Combination with features
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6. The Temporal Objects
TM_Primitive
ISO19108
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7. The Temporal Objects
TM_Primitive
ISO19108
MultiPrimitive
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8. The Temporal Objects
TemporalPosition
ISO19108
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9. The Temporal Objects
TemporalPosition
ISO19108
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10. The Temporal Objects
TemporalPosition
ISO19108
Only one internal system
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11. Textual Representation
• Necessary for the information exchange
-> The user’s view on the database level
• Some terms are set by the Temporal Schema (ISO19108)
The concerning standardisation does not go far enough
-> Requires arbitrary specifications
-> Only restrictedly suitable for a general
information exchange ?
Actually needed: WKT for time
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12. Operations
Basic functions
Operating only in the time dimension
e.g. Simple queries, Boolean operations, ISO19108-Functions
Spatio-temporal analysis
Integrated processing in the spatial and temporal dimension
e.g. ISO19108-Feature Successions
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13. Relative Position
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14. ISO19108 – Feature Successions
Feature Substitution
Feature Division
Feature Fusion
May be derived trough a combined use of
temporal and spatial operations
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15. Implementation with PostgreSQL
Why PostgreSQL?
User defined base type in PostgreSQL
Standard compliance and far-reaching possibilities in configuration
Spatial functionality provided by PostGIS -> OGC compliant
Current capabilities:
The six object types
Exemplary the three types of reference frame
Various basic functions
Examples for spatio-temporal analysis
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16. What are the predecessor and successor
associations between several countries?
Shapefile: W EIDEMANN, N. B.; DOREEN, K.; GLEDITSCH, K. S. (2010): The Geography of the International
System: The CShapes Dataset, http://nils.weidmann.ws/projects/cshapes/shapefile (2013-03-07).
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17. For each time step: In which state did the most
tornados take place?
Shapefile: NATIONALATLAS.GOV (2011): nationalatlas.gov – Map Layers, http://nationalatlas.gov/maplayers.html (2013-03-07).
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18. Perspective
Purpose: From the proof-of-concept to the first release
• Extend the range of functions
• Decent documentation
• Extensive testing
• Validation of the concept
Particular:
Managing the various reference frames
Syntax for the information exchange
User defined reference frames
Documentation with Doxygen
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19. Peter Broßeit
Peter.Brosseit@mailbox.tu-dresden.de
Masters programme ‚Geoinformation Technologies‘
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