BibTeX
@MISC{_iospress,
author = {},
title = {IOS Press Hybrid Reasoning on OWL RL},
year = {}
}
OpenURL
Abstract
Abstract. Both materialization and backward-chaining as different modes of performing inference have complementary advan-tages and disadvantages. Materialization enables very efficient responses at query time, but at the cost of an expensive up front closure computation, which needs to be redone every time the knowledge base changes. Backward-chaining does not need such an expensive and change-sensitive pre-computation, and is therefore suitable for more frequently changing knowledge bases, but has to perform more computation at query time. Materialization has been studied extensively in the recent semantic web literature, and is now available in industrial-strength systems. In this work, we focus instead on backward-chaining, and we present a general hybrid algorithm to perform efficient backward-chaining reasoning on very large RDF data sets. To this end, we analyze the correctness of our algorithm by proving its completeness using the theory developed in deductive databases and we introduce a number of techniques that exploit the characteristics of our method to execute efficiently (most of) the OWL RL rules. These techniques reduce the computation and hence improve the response time by reducing the size of the generated proof tree and the number of duplicates produced in the derivation. We have implemented these techniques in an experimental prototype called QueryPIE and present an evaluation on both realistic and artificial data sets of a size that is between five and ten billion of triples. The evaluation was performed using one machine with commodity hardware and it shows that (i) with our approach the initial pre-computation takes only a few minutes
Keyphrases
owl rl io press hybrid query time recent semantic web literature industrial-strength system artificial data set efficient backward-chaining reasoning deductive database generated proof tree change-sensitive pre-computation knowledge base response time general hybrid algorithm owl rl rule initial pre-computation efficient response large rdf data set experimental prototype front closure computation knowledge base change different mode commodity hardware