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TEMPORAL GIS FOR CADASTRE
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Zdravko Galié*, Hrvoje Tonkovié ^, Ilija Bari&ié ^, Marina Pe&un ©
i GISquadrat, Margaretenstrasse 70/1, A-1050 Vienna, Austria - galic@gisquadrat.com
e galaGIS, Trg J. F. Kennedy 6a, 10000 Zagreb, Croatia - (tonkovic, barisic)@galagis.com
* Sisak County Cadastral Office, Trg hrvatskih branitelja 9, 44000 Sisak, Croatia - katastar-sisak(@sk.tel.hr
KEY WORDS: Spatial, Temporal, Databases, GIS, Cadastre
ABSTRACT:
One of the most successful applications of GIS technology is in the field of land management. A lot of corporate GIS databases are
in development; they support the legal management and distribution of geospatial data. The representation of time within GIS is still
an important and expected development to make these systems more suited to the temporal analysis of cadastral objects. Time
integration within GIS requires a comprehensive analysis of spatio-temporal phenomena.
The traditional short transaction-based concurrency control and locking techniques have proved insufficient for applications
requiring long transaction management. This is especially true when multiple users must access the same database. Data edits or
updates of the map database in cadastre may take hours or days. During such long term edits or database updates, users want to be
assured that others do not inadvertently edit the same rows of data or feature instances that have been included in a long transaction.
Cadastre needs the capability to version data and requires that the different versions of a row or feature instance be persisted for very
long periods of time, and users should have a possibility to be able to view data as it existed at any specific moment in time.
This translates into the need to have the capability to manage the temporal properties and aspects of feature instances/rows in a
database management system. Modern temporal GIS for cadastre should implement a complete long transaction event that maintains
atomicity and concurrency. Data changes are made through revision sets which can be exclusive for one user or shared among
several database users. Users are permitted to create new versions of data to update, while maintaining a copy of the old data. The
ongoing results of the long transaction are stored persistently, assuring concurrency and consistency.
This paper introduces the functionality for long transaction management, versioning, and temporal data management in
implementing temporal GIS for the Sisak Cadastral Office.
1. INTRODUCTION perspectives in both the development of new cadastral systems
and in the improvement of or extension of existing cadastral
In several countries cadastral systems have a long history and a systems. At the moment, the first WebGIS applications are
broad range of use in taxation, land registration, land already operational in a cadastral context. In the near future this
development, urban planning and design of infrastructure. In will be extended to mobile GIS applications based on cadastral
these countries we can see a complete re-engineering of existing information (sometimes also called location-based services).
systems, due to a more business-oriented approach, based on
the requirements of the users of cadastral information. Recent The distribution of land-based phenomena and activities is
technical developments in databases, Internet and GI directly dependent on transformation and diffusion processes
technologies are related to and encapsulated in those re- that have led to the mutation and evolution of entities
engineered systems. occupying space. Conceptually, time is an essential dimension
for understanding and modelling space, which is illustrated by
Recent developments in geoinformation (GI) have a serious the increase of publications concerning databases and temporal
impact on the development of cadastral systems. Both GI GIS. Both strategic cadastral concepts (e.g. FIG, 2001) and
science and GI technology such as the ubiquitous spatial data models currently used as the foundation for GI
communication (Internet), data base management systems systems (GIS) fall short of conveying the rich and complex
(DBMS), and global positioning systems (GPS) will improve ways, which phenomena change over space and time.
the quality, cost effectiveness, performance and maintainability
of cadastral systems. A cadastral object in general consists of the four aspects: theme,
geometry, topology, and time. Still today's GIS don't handle all
Further, users and industry have accepted the standardisation of them equally well. The temporal dimension is definitely an
efforts in the spatial area by the OpenGIS Consortium and the —— important aspect of almost all phenomena of the cadastre.
International Standards Organisation (e.g. the ISO T211 Traditional databases as well as GIS delivered only a snapshot
Geographic —Information/Geomatics). This creates new of the reality; therefore there was a need for new data models
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