ICDT
2009
ACM
14 years 8 months ago
2009
ACM
The need to manage diverse information sources has triggered the rise of very loosely structured data models, known as "dataspace models." Such information management sy...
ICDT
2009
ACM
14 years 8 months ago
2009
ACM
The class of unions of conjunctive queries (UCQ) has been shown to be particularly well-behaved for data exchange; its certain answers can be computed in polynomial time (in terms...
ICDT
2009
ACM
14 years 8 months ago
2009
ACM
Marx and de Rijke have shown that the navigational core of the w3c XML query language XPath is not first-order complete ? that is it cannot express every query definable in firsto...
ICDT
2009
ACM
14 years 8 months ago
2009
ACM
We continue the study of approximating the number of distinct elements in a data stream of length n to within a (1? ) factor. It is known that if the stream may consist of arbitra...
GIS
2006
ACM
14 years 8 months ago
2006
ACM
The large amount of patterns generated by frequent pattern mining algorithms has been extensively addressed in the last few years. In geographic pattern mining, besides the large ...
GIS
2006
ACM
14 years 8 months ago
2006
ACM
The W3C's Semantic Web Activity is illustrating the use of semantics for information integration, search, and analysis. However, the majority of the work in this community ha...
GIS
2006
ACM
14 years 8 months ago
2006
ACM
In this paper we describe work on the automatic recognition of island structures. In an initial phase several test persons were asked to mark groups of islands that they perceived...
GIS
2006
ACM
14 years 8 months ago
2006
ACM
GIS
2006
ACM
14 years 8 months ago
2006
ACM
The result of a distance join operation on two sets of objects R, S on a spatial network G is a set P of object pairs <p, q>, p R, q S such that the distance of an object ...
GIS
2006
ACM
14 years 8 months ago
2006
ACM
Topological relationships between objects in space are of great importance in many disciplines. Recently, topological relationships have been defined for complex spatial objects. ...