When Hydrospheres Collide

1. When Hydrospheres Collide Lessons in Practical Environmental Ontologies John Graybeal, Luis Bermudez Marine Metadata Interoperability Project 12 October 2006

2. MMI: Brief Introduction • Started 2004 with NSF funding; recent 3-year NSF award • Mission: Improve the use and understanding of metadata in marine sciences • International participation and support • Main deliverables: web site, tools, community • 300-plus members • Numerous open-source tools like VINE, Voc2OWL • Collaborations with many in community • Technical Lead: Luis Bermudez

3. Vocabulary Integration Environment

4. Background and Motivation • Guide a marine data repository to tag data sets with the appropriate data source tag • Help a data portal discover data through semantic inferencing • Help an instrument manufacturer to categorize their instruments in a consistent and useful way • Guide other domains to better categorized their data sources

5. Background and Motivation MMI Workshop Advancing Domain Vocabularies Aug. 2005 Sensor Group

6. Plan A: A Sensors Ontology • Follow-on to Advanced Domain Vocabulary workshop last year • Multiple science domains, plus “sensors” • Workshop Sensors Team: 6-7 people • Started with GCMD, SWEET vocabularies • Formulated a technique-based hierarchy • Ontology work was to continue that effort • Some of us were nervous about the work required to make a sensors ontology

7. Plan B: A Platforms Ontology • Good to gain experience with the process • Of direct interest to several activities • SeaSearch: Roy Lowry • MBARI data systems: John Graybeal et al • Metadata interfaces: Bob Arko • Easier problem on which to start • Fewer critical concepts for categorization • Fewer existing vocabularies • Fewer stakeholders • Useful for sensor work later

8. Ontology Context

9. Tools and Resources • Concept Schemes: SWEET, CDI Platform Codes, GCMD and Wordnet. • Dictionaries: Wikipedia, Dictionary.org. • Search Engine: Google, for individual marine science and technology sites. • Tools: Protégé, SWOOP and Pellet. • Collaboration: WebEx and telephone. • Web Site: http://marinemetadata.org/sourcesont

10. Principal Players • Luis Bermudez, MMI/MBARI (Lead) • Roy Lowry, BODC • Rob Raskin, SWEET • Robert Arko, LDEO • John Graybeal, MMI/MBARI • Michael Hughes, BODC • Marilyn Drewry, UAH • Kevin O’Neill, BODC Group Photo

11. Principal Customers • Portals that want to sort or classify data by platform types • Programmers or Data Managers that want to tag their data sets with a sourceType • Interoperable systems that want to mediate between two or more controlled vocabularies • Operators, developers, manufacturers who describe their platforms in metadata records • Operation managers who manipulate assets • Funders who allocate money to/for assets

12. The “Simple” Part

13. What Are The “Rules”? • Syntactic Goals • Short words or phrases • Consistent capitalization/punctuation • Linguistic Goals • Maintain concept order (noun or modifiers first) • Avoid acronyms • At each level, divide concept space into non-overlapping concepts that fill the space • Semantic Goals • Common terms (ideally the most common) • Unambiguous words in English & American • Match other vocabularies where possible

14. The Professor says… Class Name Constructs • Adjectives-Noun placement order. In English adjective goes first. (ResearchVessel instead of VesselResearch.) Same pattern was applied in DOLCE, KOALA, PIZZA ontologies. • Prefer the common marine term over the logic term. (DriftingBuoy instead of UnmooredBuoy) • CamelCase preferred vs Hyphen and underscores. (ResearchVessel instead of Research_Vessel or Research-Vessel) (but: Nonautonomous)

15. Little Surprises Everywhere

16. Unexpected Meanings • “AUVs* operate in the hydrosphere” • To me (and many), this is earthbound liquid water • AUVs can operate there, even in canals and ponds • But to hydrologists everywhere, this includes water vapor • An airborne AUV is not a useful concept • But then, what to do with atmosphere and terrasphere? * AUV = autonomous underwater vehicle

17. No More Hydrosphere for Us! Hydrosphere

18. What Are The “Rules” (Part 2)? • How do you organize the ontology? What’s the basis for the framework? • Deployment medium was a clear winner • How do you choose between 2 equally valid alternatives? • “It depends on how you will use it.” • Helps little in a general purpose ontology • Try to keep model close to reality • Trouble coming in the sensors work…?

19. Organizational Basis

20. The Professor says… Criteria to add a new term • It is not already in the ontology. • It can have a property that differentiatesit from its siblings. (e.g. ship and boat. The dimension of a ship is bigger than a boat.) • A super-class is promoted when similarities are found among concepts. (e.g. Both Buoy and Research Vessel hasEarthRealmBase water. A new class can be created called WaterBasedPlatform.) • A term can be categorized under 2 or more categories (e.g., Amphibious Crawler).

21. The Results (Ta da!)

22. Future Work: Sensors! Sensor Metadata Interoperability Workshop October 19-20, 2006 Choosing Standards / Learning Standards http://marinemetadata.org/workshop06

23. Thank you MMI: http://marinemetadata.org Observing Sources Work: http://marinemetadata.org/sourcesont Ontologies: http://marinemetadata.org/platformonts Ontology Mailing List: ont@marinemetadata.org Email: graybeal@mbari.org | bermudez@mbari.org