Suite of Tools for Pattern-Based Transformation of OWL Ontologies Ondrej Zamazal 0 Marek Dudas 0 Jan Cerny 0 Vojtech Svatek svatekg@vse.cz 0 University of Economics , W. Churchill Sq.4, 130 67 Prague 3 , Czech Republic

Motivation The high expressivity of OWL enables us to express the same conceptualization in di erent ways. A simple example is the di erence between `class-centric' and `property-centric' modeling styles, such that the same notion is modeled as a class in the former (e.g. `Purchase') and an object property in the latter (e.g. `bought from'). Similarly, concept subordination can be expressed via a subclass hierarchy or via individuals connected by a dedicated property (ontology simpli cation as in SKOS). Style heterogeneity contributes to conceptual heterogeneity on the Semantic Web and thus represent an obstacle to reusing ontologies in advanced semantic web scenarios. In particular, two ontologies modeled in di erent styles are di cult to match or to import to one another. Furthermore, opting for a style when designing an ontology may have impact on the usability and performance of reasoners, as some features cause performance problems for certain reasoners. Finally, ontology designers may need help with inspection and repair of entity naming in an ontology. PatOMat In our approach [2] we come up with ontology transformation framework PatOMat, which is based on transformation patterns (TP).1 A TP contains two ontology patterns (the source OP and the target OP) and the description of transformation betweem them, called pattern transformation (PT). The representation of OPs is based on OWL 2, except that placeholders are allowed in addition to concrete OWL entities. Furthermore, there is the naming aspect of the OP, which is important for its detection. A PT consists of a set of transformation links and a set of naming transformation patterns. Naming transformation patterns serve for generating names for target entities. The framework prototype implementation is available either as a Java library or as three RESTful services.2 The whole transformation is divided into three steps that correspond to the three core services: OntologyPatternDetection service assigning entity placeholders, InstructionGenerator generating general and speci c transformation instructions, and OntologyTransformation service transforming an ontology according to transformation instructions. These services are based on our speci c implementation over OWL-API3 and Jena.4 Transformation process is decomposed into parts in order to enable an user intervention.

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Tools In order to support smooth application of TPs we implemented several graphical tools. Transformation Pattern Editor (TPEditor) [ 1 ] supports authoring and updating of transformation patterns. It allows their graphical modelling and export/import from/to the (XML-based) TP notation. TPEditor is available as a plugin for Eclipse. Graphical User Interface for Pattern-based Ontology Transformation (GUIPOT) is a Protege plugin allowing the user to go through all steps of transformation via a standard working environment of a knowledge engineer [ 3 ]. The Importing transformation wizard supports the ontology import use case in the sense that the user can select a content ontology design pattern, an ontology and a transformation pattern, and a speci c process will be performed. This wizard is integrated into the eXtreme Design tool supporting pattern-based ontology development and this can be plugged5 into Eclipse as well as into the NeOn toolkit.6 The Naming repair plugin supports the naming repair use case. It is integrated into the Ontology Repair and Enrichment toolkit. (ORE)7 Next, there is a web-based Downgrading application supporting the language pro ling use case.8 Following the input of the source ontology URI (and selected TP in the `one construct transformation' use case), the transformed ontology is output together with a brief transformation log. Next, we are working on web-based variants of tools for editing/applying transformation patterns. This will be available as Portal of Applicable Transformation Patterns integrating the Web-based Catalogue of Ontology Transformation Patterns (WebCOP) consisting information about each TP, Web-based Editor of Ontology transformation Patterns (WEdOP) and RESTful services for launching the transformation steps. Demo This demo is successor of the demo [ 3 ] presented at EKAW 2012. The main enhancement since then will be the integration into ORE and the webbased integration of tools (i.e. WebCOP, WEdOP and RESTful services). While the former has already been completed, we are still working on the latter (it will be available at the time of workshop). Additionally, there are two new use-cases on which we can demonstrate ontology transformation: Ontology Naming Repair and Ontology Simpli cation.

The research is supported by the EU ICT FP7 under No.257943, LOD2 project.

 1. Svab-Zamazal O. , Daga E. , Dudas M. , Svatek V. : Tools for Pattern-Based Transformation of OWL Ontologies . Presented as demo at ISWC' 11 , Bonn , 2011 . 2. Svab-Zamazal O. , Svatek V. , Iannone L. : Pattern-Based Ontology Transformation Service Exploiting OPPL and OWL-API . In: EKAW-2010 , Lisbon, Portugal, 2010 . 3. Svab-Zamazal O. , Dudas M. , Svatek V. : User-Friedly Pattern-Based Transformation of OWL Ontologies . Demo session at EKAW 2012 , Galway, Ireland, 2012 . 5 Information about these tools is available at http://owl.vse.cz:8080/tools.html 6 http://neon-toolkit.org/wiki/Main_Page 7 http://ore.aksw.org/ore 8 Available from http://owl.vse.cz:8080/Downgrading/.