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Boris Konev, Roman Kontchakov, Michel Ludwig, Thomas Schneider, Frank Wolter, Michael Zakharyaschev

Accepted for AAAI 2011

Full Version

Full version: Conjunctive Query Inseparability of OWL 2 QL TBoxes

Full Details of the Experiments

For each of the five considered ontologies, Core, Mimosa, Umbrella, IMDB, LUBM, we reproduce the experimental results below, which we obtained for extracting three different types of modules: minimal Σ-query modules (MQM), minimal strong Σ-query modules (MSQM), and minimal depleting Σ-query modules (MDQM); minimal is understood with respect to set-theoretic inclusion. For IMDB and LUBM we extracted modules for 10 randomly generated signatures containing 5 concept names and 5 role names; for the other three ontologies we used 20 randomly generated signatures with 5 concept names and 5 role names. Also, for IMDB, LUBM and Mimosa we started the module extraction process from the whole ontology, whereas for Core and Umbrella we first computed the top-bot modules for the given signatures before we further extracted the required three types of modules from the obtained top-bot modules. The experiments were conducted on PCs equipped with an Intel Core 2 Duo E6400 CPU and with 3 GB of main memory, but the amount of memory used was negligible.

Each row in the result tables below contains the results obtained for one particular signature Σ. The columns of the tables are organised as follows. The first column contains the name of considered signature Σ, which is followed in the next three columns by the number of concept names, role names, and the number of axioms of the considered TBox. The number of concept names and role names that are contained in each signature Σ is given in the subsequent two columns. The following three columns then indicate the number of concepts names, role names and the number of axioms present in the computed module. The next column then contains the number of axioms for which it could not be determined whether these axioms can be removed from the computed module or not (due to a "don't know" answer of the Σ-query entailment checker). The number of overall calls to the the Σ-query entailment checker is given in the subsequent column, whereas the last column indicates the overall CPU time that was needed to extract the module from the considered TBox and signature Σ. The minimal, maximal and average values for (most of) the columns are also given.

Mimosa (and its modules) is not available due to copyright reasons.

Mimosa Core Umbrella IMDB LUBM
Ontology .zip .zip .zip .zip
Signatures .zip .zip .zip .zip
Top-bot .zip .zip
MQM Results Results|Modules Results|Modules Results|Modules Results|Modules
MSQM Results Results|Modules Results|Modules Results|Modules Results|Modules
MDQM Results Results|Modules Results|Modules Results|Modules Results|Modules