251 search results - page 38 / 51 » Rewriting Aggregate Queries using Description Logic |
189
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FLAIRS
2009
15 years 1 months ago
2009
Knowledge compilation is a common technique for propositional logic knowledge bases. A given knowledge base is transformed into a normal form, for which queries can be answered ef...
190
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SIGMOD
2005
ACM
16 years 3 months ago
2005
ACM
We present a method to evaluate path queries based on the novel concept of partial path instances. Our method (1) maximizes performance by means of sequential scans or asynchronou...
131
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OTM
2007
Springer
15 years 9 months ago
2007
Springer
We show how Semantic Web technologies can be used to build an access control system. We follow the role-based access control approach (RBAC) and extend it with contextual attribute...
131
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DBPL
1995
Springer
15 years 6 months ago
1995
Springer
We study the problem of maintaining recursively-de ned views, such as the transitive closure of a relation, in traditional relational languages that do not have recursion mechanis...
138
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SSDBM
1999
IEEE
15 years 7 months ago
1999
IEEE
Conducting bioinformatic analyses involves biologists in expressing requests over a range of highly heterogeneous information sources and software tools. Such activities are labor...