Once upon a time (surely >6 years ago) I made an OWL file of the taxonomy of part-whole relations , which contains several parthood relations and a few meronyic-only ones that in natural language are considered ‘part’ but are not so according to mereology (like participation, membership). Some of these relations were defined with a specific domain and range that was a DOLCE category (it could just as well have been, say, GFO). Looking at it recently, I noticed it was actually a bit scruffy (but I’ll leave it here nonetheless), and more has happened in this area over the years. So, it was time for an update on contents and on design.
For the record on how it’s done and to serve, perhaps, as a comparison exercise on modeling, here’s what I did. First of all, I started over, so as to properly type the relations to DOLCE categories, with the DOLCE IRIs rather than duplicated as DOLCE-category-with-my-IRI. As DOLCE is way too big and slows down reasoning, I made a module of DOLCE, called DOLCEmini, mainly by removing the irrelevant object properties, though re-adding the SOB, APO and NAPO that’s in D18 but not in DOLCE-lite from DLP3791. This reduced the file from DOLCE-lite’s 534 axioms, 37 classes, 70 OPs, in SHI to DOLCEmini’s 388 axioms, 40 classes, 43 OPs, also in SHI, and I changed the ontology IRI to where DOLCEmini will be put online.
Then I created a new ontology, PW.owl, imported DOLCEmini, added the taxonomy of part-whole relations from  right under owl:topObjectProperty, with domain and range axioms using the DOLCE categories as in the definitions, under part-whole. This was then extended with the respective inverses under whole-part, all the relevant proper part versions of them (with inverses), transitivity added for all (as the reasoner isn’t doing it ) annotations added, and then aligned to some DOLCE properties with equivalences. This makes it to 524 axioms and 79 object properties.
I deprecated subquantityOf (annotated with ‘deprecated’ and subsumed by a new property ‘deprecated’). Several new stuff relations and their inverses were added (such as portions), and annotated them. This made it to the PW ontology of 574 axioms (356 logical axioms) and 92 object properties (effectively, for part-whole relations: 92 – 40 from dolce – 3 for deprecated = 49).
As we made an extension with mereotopology  (and also that file wasn’t great, though did the job nevertheless ), but one that not everybody may want to put up with, yet a new file was created, PWMT. PWMT imports PW (and thus also DOLCEmini) and was extended with the main mereotopological relations from , and relevant annotations were added. I skipped property disjointness axioms, because they don’t go well with transitivity, which I assumed to be more important. This makes PWMT into one of 605 (380 logical) axioms and 103 object properties, with, effectively, for parts: 103 – 40 from dolce – 3 for deprecated – 1 connection = 59 object properties.
That’s a lot of part-whole relations, but fear not. The ‘Foundational Ontology and Reasoner enhanced axiomatiZAtion’ (FORZA) and its tool that incorporates with the Guided ENtity reuse and class Expression geneRATOR (GENERATOR) method  describes a usable approach how that can work out well and has a tool for the earlier version of the owl file. FORZA uses an optional decision diagram for the DOLCE categories as well as the automated reasoner so that it can select and propose to you those relations that, if used in an axiom, is guaranteed not to lead to an inconsistency that would be due to the object property hierarchy or its domain and range axioms. (I’ll write more about it in the next post.)
Ah well, even if the OWL files are not used, it was still a useful exercise in design, and at least I’ll have a sample case for next year’s ontology engineering course on ‘before’ and ‘after’ about questionable implementation and (relatively) good implementation without the need to resorting to criticizing other owl files… (hey, even the good and widely used ontologies have a bunch of pitfalls, whose amount is not statistically significantly different from ontologies made by novices ).
 Keet, C.M., Artale, A. Representing and Reasoning over a Taxonomy of Part-Whole Relations. Applied Ontology, 2008, 3(1-2):91-110.
 Keet, C.M. Detecting and Revising Flaws in OWL Object Property Expressions. 18th International Conference on Knowledge Engineering and Knowledge Management (EKAW’12), Oct 8-12, Galway, Ireland. Springer, LNAI 7603, 252-266.
 Keet, C.M., Fernandez-Reyes, F.C., Morales-Gonzalez, A. Representing mereotopological relations in OWL ontologies with OntoPartS. 9th Extended Semantic Web Conference (ESWC’12), Simperl et al. (eds.), 27-31 May 2012, Heraklion, Crete, Greece. Springer, LNCS 7295, 240-254.
 Keet, C.M., Khan, M.T., Ghidini, C. Ontology Authoring with FORZA. 22nd ACM International Conference on Information and Knowledge Management (CIKM’13). ACM proceedings, pp569-578. Oct. 27 – Nov. 1, 2013, San Francisco, USA.
 Keet, C.M., Suarez-Figueroa, M.C., Poveda-Villalon, M. Pitfalls in Ontologies and TIPS to Prevent Them. In: Knowledge Discovery, Knowledge Engineering and Knowledge Management: IC3K 2013 Selected papers. Fred, A., Dietz, J.L.G., Liu, K., Filipe, J. (Eds.). Springer, CCIS 454, pp. 115-131. 2015.
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