Modularity has been and continues to be one of the central research topics in ontology engineering. The number of ontologies available, as well as their size, is steadily increasing. There is a large variation in subject matter, level of speci cation and detail, intended purpose and application. Ontologies covering di erent domains are often developed in a distributed manner; contributions from di erent sources cover di erent parts of a single domain. Not only is it di cult to determine and de ne interrelations between such distributed ontologies, it is also challenging to reconcile ontologies which might be consistent on their own but jointly inconsistent. Further challenges include extracting the relevant parts of an ontology, re-combining independently developed ontologies in order to form new ones, determining the modular structure of an ontology for comprehension, and the use of ontology modules to facilitate incremental reasoning and version control.
Modularity is envisaged to allow mechanisms for easy and exible reuse, combination, generalization, structuring, maintenance, collaboration, design patterns, and comprehension. This is analogous to the role of modularity in software engineering, where there are well-understood notions of modularity that have led to generally accepted and widely supported mechanisms for the named tasks. In contrast, modularity for ontologies is still an active research eld with open questions because existing approaches are heterogeneous and less universally applicable. For ontology engineering, modularity is central not only to reducing the complexity of understanding ontologies, but also to maintaining, querying and reasoning over modules. Distinctions between modules can be drawn on the basis of structural, semantic, or functional aspects, which can also be applied to compositions of ontologies or to indicate links between ontologies.
In particular, reuse and sharing of information and resources across ontologies depend on purpose-speci c, logically versatile criteria. Such purposes include \tight" logical integration of di erent ontologies (wholly or in part), \loose" association and information exchange, the detection of overlapping parts, traversing through di erent ontologies, alignment of vocabularies, module extraction possibly respecting privacy concerns and hiding of information, etc. Another important aspect of modularity in ontologies is the problem of evaluating the quality of single modules or of the achieved overall modularization of an ontology. Again, such evaluations can be based on various (semantic or syntactic) criteria and employ a variety of statistical/heuristic or logical methods.
Recent research on ontology modularity has produced substantial results and approaches towards foundations of modularity, techniques of modularization and modular developments, distributed and incremental reasoning, as well as the use of modules in di erent application scenarios, providing a foundation for further research and development. Since the beginning of the WoMO workshop series, there has been growing interest in the modularization of ontologies, modular development of ontologies, and information exchange across di erent modular ontologies. In real life, however, integration problems are still mostly tackled in an ad-hoc manner, with no clear notion of what to expect from the resulting ontological structure. Those methods are not always e cient, and they often lead to unintended consequences, even if the individual ontologies to be integrated are widely tested and understood.
Topics covered by WoMO include, but are not limited to: What is Modularity? { Kinds of modules and their properties { Modules vs. contexts { Design patterns { Granularity of representation Logical/Foundational Studies { Conservativity and syntactic approximations for modules { Modular ontology languages { Reconciling inconsistencies across modules { Formal structuring of modules { Heterogeneity Algorithmic Approaches { Distributed and incremental reasoning { Modularization and module extraction { Sharing, linking, and reuse { Hiding and privacy { Evaluation of modularization approaches { Complexity of reasoning { Implemented systems Application Areas { Modularity in the Semantic Web { Life Sciences { Bio-Ontologies { Natural Language Processing { Ontologies of space and time { Ambient intelligence { Social intelligence { Collaborative ontology development and ontology versioning Previous events. The WoMO 2013 workshop follows a series of successful events that have been an excellent venue for practitioners and researchers to discuss latest work and current problems. It is intended to consolidate cuttingedge approaches that tackle the problem of ontological modularity and bring together researchers from di erent disciplines who study the problem of modularity in ontologies at a fundamental level, develop design tools for distributed ontology engineering, and apply modularity in di erent use cases and application scenarios. Previous editions of WoMO are listed below. The links refer to their homepages and proceedings.
WoMO 2006. The 1st workshop on modular ontologies, co-located with ISWC 2006, Athens, Georgia, USA. Invited speakers were Alex Borgida (Rutgers) and Frank Wolter (Liverpool). Organizers and program chairs were http://www.cild.iastate.edu/events/womo.html http://sunsite.informatik.rwth-aachen.de/Publications/CEUR-WS/Vol-232 WoMO 2007. The 2nd workshop, co-located with K-CAP 2007, Whistler BC, Canada. The invited speaker was Ken Barker (Texas at Austin). http://sunsite.informatik.rwth-aachen.de/Publications/CEUR-WS/Vol-315 WoRM 2008. The 3rd workshop in the series, co-located with ESWC 2008, Tenerife, Spain, entitled `Ontologies: Reasoning and Modularity' had a special emphasis on reasoning methods. http://dkm.fbk.eu/worm08 http://sunsite.informatik.rwth-aachen.de/Publications/CEUR-WS/Vol-348 WoMO 2010. The 4th workshop in the series, co-located with FOIS 2010, Toronto, Canada. Invited speakers were Simon Colton (London) and Marco Schorlemmer (Barcelona). http://www.informatik.uni-bremen.de/%7Eokutz/womo4 http://www.booksonline.iospress.nl/Content/View.aspx?piid=16268 WoMO 2011. The 5th workshop in the series, co-located with ESSLLI 2011, Ljubljana, Slovenia. Invited speakers were Stefano Borgo (Trento), Stefan Schulz (Graz) and Michael Zakharyaschev (London). http://www.informatik.uni-bremen.de/%7Eokutz/womo5 http://www.booksonline.iospress.nl/Content/View.aspx?piid=20369 WoMO 2012. The 6th workshop in the series, co-located with ICBO/FOIS 2012, Graz, Austria. Invited speakers were Thomas Eiter (Vienna) and Luciano Sera ni (Trento). http://www.informatik.uni-bremen.de/ ts/womo2012/ http://ceur-ws.org/Vol-875/ Organizers of the previous editions and editors of the proceedings were Diego Calvanese (Bozen-Bolzano) { 2008; Bernardo Cuenca Grau (Manchester, Oxford) { 2007, 2008, 2010; Peter Haase (Karlsruhe) { 2006; Jie Bao (Rensselaer) { 2010; Joana Hois (Bremen) { 2010; Vasant Honovar (Iowa State) { 2006, 2007; Oliver Kutz (Manchester, Bremen) { 2006, 2010, 2011; Ulrike Sattler (Manchester) { 2008; Anne Schlicht (Mannheim) { 2007; Thomas Schneider (Bremen) { 2011, 2012; Luciano Sera ni (Trento) { 2008; Evren Sirin, (Clark & Parsia LLC, Washington DC) { 2008; York Sure (Karlsruhe) { 2006; Andrei Tamilin (Trento) { 2006, 2008; Michael Wessel (Hamburg) { 2008; Dirk Walther (Madrid) { 2012; Frank Wolter (Liverpool) { 2007, 2008 This volume contains the papers presented at the 7th International Workshop on Modular Ontologies (WoMO 2013) held on September 15, 2013 in Corunna, Spain as a satellite event of the conference LPNMR 2013. We received 9 submissions. Each submission was reviewed by three program committee members. The committee decided to accept ve papers for long or short presentations. The program also included two invited talks: { Till Mossakowski (University of Bremen, Germany)
The Distributed Ontology, Modeling and Speci cation Language { George Vouros (University of Piraeus, Greece)
Combining ontologies in settings with multiple agents Acknowledgments. We would like to thank the PC members and the additional reviewers for their timely reviewing work, our invited speakers for delivering keynote presentations at the workshop, and the authors and participants for contributing to the workshop program. We would also like to thank the organizers of LPNMR 2013 for hosting the WoMO workshop, the IAOA and SINTELNET for their generous nancial support, and the EasyChair developers for greatly simplifying the work of the program committee.
September 27, 2013 Manchester, Toronto, Madrid and Dresden Chiara Del Vescovo
Torsten Hahmann
David Pearce Dirk Walther Fast atomic decomposition using axiom dependency hypergraphs : : : : : : : : 61
Francisco Mart n-Recuerda and Dirk Walther Short Papers Towards a Uni ed Approach to Modular Ontology Development Using the Aspect-Oriented Paradigm : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 73
Ralph Schafermeier and Adrian Paschke Kenneth Baclawski Eva Blomqvist Alex Borgida Stefano Borgo Gerhard Brewka Mike Dean Chiara Del Vescovo (co-chair) Thomas Eiter Pawel Garbacz
Northeastern University, Boston, USA Linkoping University, Sweden Rutgers University, Piscataway, USA Laboratory for Applied Ontology, ISTC-CNR, Trento, Italy University of Leipzig, Germany Raytheon BBN Technologies, Ann Arbor, USA The University of Manchester, UK