In this paper the problem of matching a query with imprecise or missing data is analyzed for geographic information systems, and an approach for the relaxation query constraints is proposed. This approach, similarly with the 9-intersection matrix between two sets of points presented in [1] [2] [3], proposes the representation of two symbolic graphical objects (SGO) in terms of interior, boundary, and exterior points, applied to each of the configurations between two objects. The paper distinguishes the different configurations considering the results obtained from the 9 intersections, not only by whether results are null or not null. This approach allows a more detailed similarity graph to be defined. The aim of the proposed methodology is to relax geographical query constraints, in order to obtain meaningful answers for imprecise or missing data. In this paper the polyline-polygon case is discussed in detail.
Relaxing constraints on GeoPQL operators to improve query answering
D'Ulizia Arianna;Ferri Fernando;Grifoni Patrizia;Rafanelli Maurizio
2006
Abstract
In this paper the problem of matching a query with imprecise or missing data is analyzed for geographic information systems, and an approach for the relaxation query constraints is proposed. This approach, similarly with the 9-intersection matrix between two sets of points presented in [1] [2] [3], proposes the representation of two symbolic graphical objects (SGO) in terms of interior, boundary, and exterior points, applied to each of the configurations between two objects. The paper distinguishes the different configurations considering the results obtained from the 9 intersections, not only by whether results are null or not null. This approach allows a more detailed similarity graph to be defined. The aim of the proposed methodology is to relax geographical query constraints, in order to obtain meaningful answers for imprecise or missing data. In this paper the polyline-polygon case is discussed in detail.| File | Dimensione | Formato | |
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