In this paper we address the problem of formalizing quali- tative topological relationships between geographical objects in a Geo- graphical Pictorial Query Language (GeoPQL) in order to completely capture the semantics of the user queries. We focus on the polygon- polyline topological relation and we dene a 16-intersection matrix that has been conceived to enhance and distinguish the semantics of cells' content with respect to the well-known 9-intersection matrix. On the ba- sis of such distinctions, we revise the geographic operators of GeoPQL and we give their formal semantics. In order to implement our proposed 16-matrix, we invoked in GeoPQL the open source Java libraries JTS Topology Suite, which conforms to the Simple Features Specication for SQL published by the Open GIS Consortium-OGC. Finally, the proposed 16-intersection matrix is illustrated through some query examples.
A 16-intersection matrix for the Polygon-Polyline Topological Relation for Geographic Pictorial Query Languages
A Formica;M Mazzei;E Pourabbas;M Rafanelli
2012
Abstract
In this paper we address the problem of formalizing quali- tative topological relationships between geographical objects in a Geo- graphical Pictorial Query Language (GeoPQL) in order to completely capture the semantics of the user queries. We focus on the polygon- polyline topological relation and we dene a 16-intersection matrix that has been conceived to enhance and distinguish the semantics of cells' content with respect to the well-known 9-intersection matrix. On the ba- sis of such distinctions, we revise the geographic operators of GeoPQL and we give their formal semantics. In order to implement our proposed 16-matrix, we invoked in GeoPQL the open source Java libraries JTS Topology Suite, which conforms to the Simple Features Specication for SQL published by the Open GIS Consortium-OGC. Finally, the proposed 16-intersection matrix is illustrated through some query examples.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.