An application of problem and product ontologies for the revision of beach nourishments

Abstract

An ontological approach in GIS serves as a framework for the conceptualization of processes in the real world. In this paper, we examine an application in coastal change in the Netherlands, whereby beaches are subject to artificial nourishment to offset the effect of severe erosion. The use of ontologies helps to define two scenarios: S_I determined by the regulations from the Ministry for Public Works; S_II grounded on the abilities from an existing spatial dataset. A comparison between S_I and S_II shows that 72.8% of the objects suitable and unsuitable for nourishment are correctly classified. A higher overlap is found in areas where actual beach nourishments were carried out. Inaccuracies in attributes influence the determination of the objects. A sensitivity analysis applied to altitude illustrates a significant increase of objects suitable for nourishment for both scenarios, when altitude is decreased within the lower limit of the root mean square error for the 95% confidence interval. Moreover, the sensitivity of altitude shows that artificial boundaries for beach nourishment objects are not reasonable and consequently should be treated as vague objects.

Keywords:

• Problem ontology
• Product ontology
• Quality issues
• Fitness for use
• Accuracy assessment
• Coastal movement
• Object determination

Acknowledgements

This work was funded by the European Community, under IST‐1999‐14189 project REV!GIS. The datasets have been made available by Rijkswaterstaat and RIKZ. Thanks are due to Arta Dilo for contributions to the manuscript.