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Tools
Ontology Browser
A demo of the Star Wars Ontology is available to browse.
Classes, properties, individuals etc can all be browsed to understand the structure of the ontologies. Cloud views can give a quick feel for where the detail is eg instance usage
This demo is a running on the Ontology Browser, paired version of the ontology browser, specifically loaded with all.owl.ttl.
It is hosted on a cheap tier web server, so please don’t expect extremely fast responses for some queries.
Querying with Pellet (Openllet) reasoner is possible on the DL Query page.
This also supports set subtraction between queries which is useful where closure is not available. Essentially mapping to “A is true but B is not known” (weaker than “A and not B”).
Who worked for the Jedi Order that was not a Jedi? Cid, who was an informant
You can even switch to the Dark Side if you prefer.
Protege
We used Protege to build this ontology
Reasoning
Use the Pellet reasoner
- Select
Pellet
from theReasoner
menu. - Select
Start Reasoner
to show inferences in the model
Other reasoners are available, but each has different performance issues
Protege Known Issues
- Using Turtle as a file format means changes to base cannot be saved if other ontologies loaded
- bug raised - https://github.com/protegeproject/protege/pull/1025
- Selection model and entity focus is very buggy
- clicking/finding an entity frequently does not navigate to that entity
- sometimes the focus changes when adding relations/subclass axioms
Protege Features
DL Query Tab
For off the cuff queries as simple as year value -22
Individual Hierarchy Tab
after
- Select
hide orphans
- Navigate the
after
tree withinverse property
- ideally use
during
for children andbefore
for sibling order
memberOf
location
- Temporarily remove
Transitive(location)
and navigate through fromGalaxy
- ships make this messy
Issues
- Requires the reasoner - would be nice to also see asserted tree
- eg transitivity makes the tree messy with individuals showing at all levels
- lots of duplicate nodes in top level of tree - bug?
- ideal if the nodes worked for selection, but they don’t
- we’d require a more advanced tree ideally that allows ordering of siblings by a property (eg after)
OWLDoc
Export HTML rendering of the ontology for browsing (read only/asserted only). Seems bugged now.
- html frames not working (in Chrome at least).
- entity pages contain lots of assertions about other entities - looks like this is due to the ontology being modularised.
WebProtege
https://webprotege.stanford.edu/
More limited (eg cannot use a reasoner?) But can import multiple ontologies and looks to have good multi-user support now.
https://protegewiki.stanford.edu/wiki/WebProtegeUsersGuide#Viewing_and_Editing_OWL_2_Ontologies