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Coastal Atlas Interoperability - Ontologies (continued)

Coastal Atlas Interoperability - Ontologies (continued). Luis Bermudez Stephanie Watson Marine Metadata Interoperability Initiative. 1. Welcome back. Recap Define an ontology Play with concepts Details on components of ontologies. 2. Ontologies .. good for expressing formally.

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Coastal Atlas Interoperability - Ontologies (continued)

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  1. Coastal Atlas Interoperability - Ontologies(continued) Luis Bermudez Stephanie Watson Marine Metadata Interoperability Initiative 1

  2. Welcome back • Recap • Define an ontology • Play with concepts • Details on components of ontologies 2

  3. Ontologies .. good for expressing formally • controlled vocabularies • mappings • categories • knowledge of a domain how ? • formal • machine friendly how ? • RDF • Web Resources

  4. Ontologies basic definition • capturing the knowledge of a domain, including simple controlled vocabularies • expressing hierarchies of concepts • interrelating vocabularies via formal mappings formal mechanism for:

  5. Components of an Ontology • Classes • Individuals • Properties • But first... what is a concept ?

  6. What is a Concept ?Graph of Concepts Explicit representation of realities: Body of Water LAKE Feature hasShape

  7. Concept Maps

  8. Warming upGraph of Concepts 38

  9. Concept Maps (10 min) • Open CMAP tools • Create a concept map about what you would expect to find on a Recreational Atlas Web site

  10. Classes • Classes define concepts in a domain • Nouns, boxes in previous exercise • Classes are organized in hierarchies: • Example: Habitat is super class of Wetland • Classes are sets that contain individuals 42

  11. Individuals • Individuals represent real objects in the domain in which we are interested. • They are the members of a class. Wetland 42 Elkhorn Slough NERR Malheur National Wildlife Refuge 48

  12. Ontology Example GeographicFeature Class City Wetland Individual Object Property isLocatedIn hasName: Elkhorn Slough hasName: Monterey Area_in_skm: xxx Datatype Property

  13. Classes - subclasses Geographic Feature City Wetland

  14. Individuals GeographicFeature Class City Wetland Individual

  15. Properties • Properties are relationships (loosely, verbs) between two individuals. • lines in previous exercise • 2 types: • Object Properties link an individual to an individual • Datatype properties link an individual to a Literal (String, integer, etc..). Defined as XML Schema datatypes. 45

  16. Object Properties GeographicFeature Class City Wetland Individual Object Property isLocatedIn Domain of isLocatedIn Range of isLocatedIn

  17. Domain and Range City Wetland isLocatedIn Class Wetland is Domain of isLocatedIn Class City is Range of isLocatedIn Object Properties have classes as domains Object Properties have classes as ranges ... connect objects, which are instances of a class

  18. Datatype Properties GeographicFeature Class City Wetland Individual Object Property isLocatedIn hasName: Elkhorn Slough hasName: Monterey Area_in_skm: 70 Domain is a class Range is a simple type : String, float, etc... Datatype Property

  19. Ontology Example GeographicFeature Class City Wetland Individual Object Property isLocatedIn hasName: Elkhorn Slough hasName: Monterey Area_in_skm: 70 Datatype Property

  20. Viewing a Simple Ontology • View an example ontology containing the Elkhorn Slough National Estuarine Research Reserve and the Malheur National Wildlife Refuge 69

  21. Open Ontology and Explore Classes • View Classes tab • Note icons on upper right • create subclass • create sibling class • delete class • menu triangle with different options including viewing the hierarchy as starting with class “thing”. This latter menu option is important, since this is not the default of TopBraid, but is a very useful way to view a class hierarchy.

  22. Explore Classes • Double click on class “Wetland” (subclass of “GeographicFeature”) in wetlands.owl • view class form, note annotations and axioms; can drag and drop annotation properties onto the form • can create subclasses by clicking on the name of the (super) class in the view class diagram • see other classes and their relationships to (properties) this class • view class diagram • view instances tab, see list of instances of this class • view import tab (this is where the namespaces of imported ontologies would appear) • view domain tab • view SPARQL tab Queries on your class(es)

  23. Explore Individuals • View instances tab • Note the icons in the upper right. You can create (choosing the class to which it will belong, first) or delete an instance, or use the instance menu to accomplish such tasks as exporting the instances to a spreadsheet. • Double click on the instance “ElkhornSloughNERR” • View the resource form (just above the instances tab). • Note the name of the instance annotations, properties (especially note that the property list for the instance will include any properties identified for the class of which that instance is a member)

  24. Explore Properties • Double click on the property “hasActivity” • View properties tab (on right) • Note icons for creating property, deleting property, menu triangle for creating specific types of properties (object, data type and annotation properties). • View properties form • Note that each property has a name, may have annotations, and may have axioms (e.g., domain, range) • think of domain as the class that has this property (e.g., “Wetland”) and range as the valid “value” for the property (e.g., “Activity”) • Note that each property can also be a(n): • Subproperty of (properties can be hierarchical) • Inverse of • at the bottom, you should also see what type of property it is (object, datatype)

  25. Explore Properties • View properties form (continued) • Note menus on top right on the property form, that can: • add widget for property • show widgets for all properties with matching domains, • arrange widgets in 2 columns • also, an inverted triangle menu with lots of options • E.g., will find the property name on Google, Wikipedia • E.g., will find all the usages of the property in your workspace, etc.)

  26. Exercise 70

  27. Hands on exercise TBC 69

  28. Exploring TBC (1:40 - 2:30) • Follow the guide: TBC Getting-Started-Guide • Let’s all create a simple ontology ... follow the screen instructions

  29. Atlas Interoperability Exercise For any interoperability endeavor the first thing that should happen is getting the requirements right ! Use Cases

  30. Atlas Interoperability

  31. Use Case and Proposed User Interface The topics found are the ones that will be explicitly created as well as inferred ones based on logic.

  32. Atlas OntWeb

  33. Q: Where are the data coming from ? A: Distributed sources, which are simulated by each ontology you are creating. Very different from traditional databases. Note...

  34. Process • Create person-topic ontology (- 3:30) • Break (3:30 - 3:45) • Map with Upper Level person-topic ontology (- 4:30) • Publish to SVN • View web application - use case 1 completed ! • Discussion (-5:00) • Map topics with Atlas Topics • Publish mappings

  35. Create a simple ontology that captures topics of interest of persons • Use concepts from the CMAP exercise, if possible • Create at least: • 3 Classes (on any level) • 1 Object Property - define domain and range • 2 Datatypes Properties - define domain and range • 2 Individuals for class Person, and 4 for each of the other classes you create • Add properties and values to individuals. e.g. luishasInterestYOGA • For example, include as topics recreational concepts that you would expect to find on an atlas • Have fun • If problems occur, use help system or TBC tutorial. If more problems occur, raise your hand 75

  36. Make your person-topic ontology (XYZ) interoperable with the FOAF ontology 75

  37. Interoperability

  38. We will make your person-topic ontology (XYZ) interoperable with the FOAF ontology your ontology aX.owl 75

  39. Experts are now “Atlases” • Which two groups created more topics than anybody else ? • They will become atlases. They will map their classes and properties to a a super atlas ontology. • Change the class name “person” to “atlas” to avoid confusion. • Import superatlas.owl (an upper atlas ontology) • Make your classes subclasses of Atlas, and Feature. Make one of your properties a subclass of hasFeature. • Follow similar instructions as the other groups to make your ontology aligned with superatlas.owl.

  40. Map with Person Upper Level Ontology (foaf.owl) • Import upper person ontology foaf.owl 75

  41. Map with person upper ontology Make your classes as subclasses of a FOAF class. For example if you have a class Person, make it subclass of foaf:Person 75

  42. Make one of your properties sub-properties of foaf:topic_of_interest 75

  43. Commit to SVN 75

  44. Check the web - is your filename there ? URL is: http://marinemedata.org:9600/fs 75

  45. Discussion • Did you need to do any changes to your ontology ? • We are presenting values of instances in the web interface, but this is not always the case. 75

  46. Discussion • You are a FOAF person because you created a statement that said that: • Youfoaf:topic_of_interestTopic • AND • foaf:topic_of_interest has domain foaf:person • Test it ! • Make your person class not • a subclass of foaf:Person • Run the inference • engine 75

  47. End Day 1 76

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