reasoning on spatial semantic integrity constraints

Reasoning on conceptual schemas of spatial data

Faculty of Environmental Sciences, Department of Geosciences, Professorship of GIS

Stephan Mäs

Dagstuhl Seminar on Automated Reasoning on Conceptual Schemas20th May 2013

Overview

1. Specifics of Spatial Data Schemas

2. Reasoning on Spatial Semantic Integrity Constraints

Reasoning on conceptual schemas of spatial data Stephan Mäs 2


http://wetterstationen.meteomedia.de/

http://wetterstationen.meteomedia.de/

Peculiarities of Spatial Data Schemas

Combination of spatial, temporal and thematic components

Basic “datatypes” for spatial concepts Fields Geometry types for object data Topology

Representation of different scale, granularity and levels of abstraction

Spatial reference systems

Units of measure

…


Source: Bartelme 1995

Integrity rules in spatial data schemas

On geometries e.g. closed polygons, self intersecting lines

Semantic integrity constraints on (implicit) spatial relations partonomic relations e.g. between administrative regions

non-overlapping and covering regions

Topological relations

Metric relations

Direction relations

Combinations with thematic constraints

Constraints between different scales / LoD

Transaction rules

…


Source: Plümer et al. 1997

Formalization is still an issue

Examples of Spatial Semantic Integrity Constraints

Topological Restrictions Contour lines don't intersect with lakes An alluvial forest is inside of a floodplain

Orientation / directional restrictions The backyard must be at the rear of a house Road signs have to face the direction opposite

of the driving lane they are attached to

Metric restrictions Petrol stations must be in at least 300m distance from schools


Reasoning on spatial semantic integrity constraints


Each alluvial forest is inside of exactly one floodplain

All floodplains are disjoint from all nuclear power stations

All alluvial forests are disjoint from all nuclear power stations

All alluvial forests contain a nuclear power station

Reasoning on spatial relations

Inheritance of Class Relations Stephan Mäs 8

Composition of spatial relations

ab

c

explicit knowledge: - a inside b and b disjoint c

implicit knowledge:

- a is disjoint from c

Finite set of spatial relations

with defined logics

For example

Compositions of spatial relations


Egenhofer, M. (1994): Deriving the Composition of Binary Topological Relations.

Constraint Satisfaction Problems

Nodes represent objects

Edges represent (spatial) relations


Reasoning on spatial sem. integrity constraints


two level reasoning approach:

separate the compositions of

the cardinality restrictions from

those of the spatial relations

Combined Composition of

Integrity Constraints /

Class Relations

Composition Table of the Cardinality Restrictions

Class Level

Composition Table of the Instance Relations

Instance Level

Other things to consider

Restrictions of the number of instances

Symmetry

Infinity Problems


#countries = #capitals

Recent work: Inheritance of Sem. Integrity Constraints


Subclasses inherit properties of the superclass in the hierarchy

dependencies between the cardinality restrictions of a relation at different hierarchy levels

The relation between the superclass and the class outside the hierarchy subsumes the relations between the subclasses and the class outside the hierarchy.

Reasoning on Spatial Semantic Integrity Constraints


Mäs, Stephan (2013): Reasoning on Class Relations: an Overview. In: Raubal, Martin; Mark, David M.; Frank, Andrew U. (Eds.), Cognitive and Linguistic Aspects of Geographic Space - New Perspectives on Geographic Information Research. Springer Lecture Notes in Geoinformation and Cartography

Mäs, Stephan (2008): Reasoning on Spatial Relations between Entity Classes. GIScience 2008 Lecture Notes in Computer Science 5266

Mäs, Stephan (2007): Reasoning on Spatial Semantic Integrity Constraints. COSIT 2007 Lecture Notes in Computer Science 4736

Fakultät Forst, Geo- und Hydrowissenschaften, Fachrichtung Geowissenschaften, Professur Geoinformationssysteme

Stephan Mäswww.stephanmaes.de

Thanks !

reasoning on spatial semantic integrity constraints

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