412 search results - page 15 / 83 » Aggregate queries over ontologies |
AMW
2010
13 years 10 months ago
2010
In this work we present in-network techniques to improve the efficiency of spatial aggregate queries. Such queries are very common in a sensornet setting, demanding more targeted t...
ESWS
2010
Springer
14 years 8 days ago
2010
Springer
The Semantic Web movement has led to the publication of thousands of ontologies online. These ontologies present and mediate information and knowledge on the Semantic Web. Tools ex...
ICDE
2005
IEEE
14 years 10 months ago
2005
IEEE
Resource Description Framework (RDF) is a rapidly expanding web standard. RDF databases attempt to track the massive amounts of web data and services available. In this paper, we ...
DLOG
2011
13 years 14 days ago
2011
We show that, although conjunctive queries over OWL 2 QL ontologies are reducible to database queries, no algorithm can construct such a reduction in polynomial time without changi...
TSC
2010
13 years 3 months ago
2010
Data-Providing (DP) services allow query-like access to organizations' data via web services. The invocation of a DP service results in the execution of a query over data sour...