OntoSat

Welcome to OntoSat

OntoSat is an application designed to saturate an ontology based on its assertional axioms.

For a given ontology with the axioms r(a, b) and P(b), the axiom ∃r.P(a) naturally follows. However, existing reasoners such as ELK or HermiT only make inferences in terms of known classes, limiting their ability to deduce such axioms in their set of consequences.

This application aims to saturate the ontology adding these kinds of logical inferences.

For each axiom of the form r(A, B) from the original ontology, the application retrieves all the classes C associated with the object individual and adds a new axiom of the form ∃r.C into the subject individual. If the object individual has no classes associated, the saturation process will add the axiom ∃r.⊤.

Users can choose whether the saturation process adds assertional or terminological axioms. Assertional axiom saturation is selected by default. If terminological saturation is selected, a named class rC ≡ ∃r.C is added to the ontology.

Note

Given a role assertion r(a, b), the a is known as the subject individual while b is the object individual.

Getting started

Requirements

There exist some environment requirements if you want to run the OntoSat. Make sure you have your environment set with softwares listed below.

• Java Development Kit (JDK) at version: 20.0.2
• Gradle at version: 8.5

Build and Run

To build the project, run the following command at the project's directory:

./gradlew build

Note

The first time you run the build, Gradle will check whether you already have the required dependencies in your cache under your ~/.gradle directory or not. If not, the libraries will be downloaded and stored there. The next time you run the build, the cached versions will be used. The build task compiles the classes, runs the tests, and generates a test report.

To generate a .jar file with all dependencies, run:

./gradlew jar

The generated JAR file will be available at: build/libs/ontosat-1.0-SNAPSHOT.jar

Now, run:

java -jar build/libs/ontosat-1.0-SNAPSHOT.jar

to execute the application.

Running options

Parameters	Description
-h, --help	Prints the help message.
-i, --ontology	Specifies the path to the input ontology.
-o, --saturated-ontology	Specifies the path where the saturated ontology will be stored
-m, --mode	Defines the saturation mode, which can be either assertional or terminological. The assertional mode is selected by default.

Test

To run the existing unit tests, execute:

./gradlew test

Documentation

• Master's Thesis - Davy Souza