Answering queries over ontologies is an important issue for the Semantic Web. Aggregate queries were widely studied for relational databases but almost no results are known for ag...
Diego Calvanese, Evgeny Kharlamov, Werner Nutt, Ca...
In emerging applications such as location-based services, sensor monitoring and biological management systems, the values of the database items are naturally imprecise. For these ...
Reynold Cheng, Lei Chen 0002, Jinchuan Chen, Xike ...
In moving object environments, it is infeasible for the database tracking the movement of objects to store the exact locations of objects at all times. Typically, the location of a...
Reynold Cheng, Sunil Prabhakar, Dmitri V. Kalashni...
A probabilistic learning model for vague queries and missing or imprecise information in databases is described. Instead of retrieving only a set of answers, our approach yields a...