1. OBOE Model Changes SONet Meeting June 7-9, 2010

2. Motivation for Changes Remove redundancy in the model –Mainly in Dimension (characteristics) Make it more “reasonable” –Make better use of OWL constraints for inference Simplify –How measured values are handled –Context and relationships More modeling flexibility –Allow observed relationships between entities

3. Overview of OBOE 1.0 Beta Context hasObservationContexthasContextObservation * 1..1 * Relationship hasContextRelationship 1..1 * hasEntityRelationshiphasRelationshipEntity * 1..1 * EntityObservation ofEntity 1..1 * Measurement measurementFor hasMeasurement + hasPrecision : decimal + hasValue : anySimpleType 1..1 * CharacteristicValue characteristicOf hasCharacteristic hasCharacteristicValue 1..1 * * CharacteristicProtocol MeasurementStandard ofCharacteristic usesProtocol usesStandard 1..1 * * *

4. Proposed Changes (OBOE 1.1 Beta) Entity Characteristic Observation Measurement Protocol Standard measurementFor hasMeasurement + hasPrecision : decimal + hasMethod : anyType ofCharacteristic usesProtocol usesStandard ofEntity hasContext 1..1 * * * * * * hasValue 1..1 * * standardFor protocolFor valueFor observedBy contextFor measuredBy

5. Overview of OBOE 1.0 Beta Entities can have (simple) characteristics –Similar to OWL data type properties –Length, Height, Mass,... Values have “value codes” –Implicit connection to data Entity Characteristic CharacteristicValue characteristicOf hasCharacteristic hasCharacteristicValue 1..1 * * (e.g., DamagedValue) (e.g., Condition) (e.g., Shell) + hasCode : anySimpleType

6. Proposed Changes (OBOE 1.1 Beta) Remove Characteristic Value –Treat primitives as special entities (like in “pure” OOP) –Values as primitives, asserted types (punning), entities Allow complex Characteristics –Data and object properties Improved reasoning power –Characteristics and entities constrained through measurements

7. Overview of OBOE 1.0 Beta Observations are made within a context –The “environment” or “state” assumed to be present during an observation –Observations related via a Relationship (like part-of, within, etc.) EntityObservation ContextRelationship hasContextRelationship ofEntity hasObservationContext hasContextObservation hasEntityRelationship hasRelationshipEntity * 1..1 * * * * *

8. Proposed Changes (OBOE 1.1 Beta) Removed context relationships –Replaced by more powerful characteristics (entity-entity) –But, retains same meaning of context Simplified context representation –Now just an object property (hasContext)

9. Other Proposed Changes (OBOE 1.1 Beta) Added inverse properties –This gives many “access paths” through the ontology … which is useful for reasoning (constraints) –For example, can fully constrain a WingCount characteristic to have integer values and be of Birds within a Measurement: WingCount measuredBy only (Measurement and (hasValue only int) and (measurementFor only Bird)) Removed dimension structure from characteristic –Now just a plain-old hierarchy –Units still retain the structure (with small changes) –Characteristic constrained through measurements (like above)

10. Overview of OBOE 1.0 Beta MeasurementStandard Unit BaseUnit SimpleDerivedUnit ComplexDerivedUnit + hasPower = 1 + hasPower = int hasBaseUnit 1..1 * U hasUnit 2..* * Characteristic Dimension BaseDimension SimpleDerivedDimension ComplexDerivedDimension + hasPower = 1 + hasPower = int hasBaseDimension 1..1 * U hasDimension 2..* * forCharacteristic Note: Implicit constraints that must be enforced by the application (i.e., not by a reasoner)

11. Proposed Changes (OBOE 1.1 Beta) MeasurementStandard Unit BaseUnit DerivedUnit CompositeUnit + hasPower = int hasUnit 1..1 * U hasUnit 2..* * Characteristic PhysicalCharacteristic standardFor o hasCharacteristic Characteristics can be used over a variety of units and standards … no restriction on structuring Enables many “surrogates” for a characteristic (like density …)

12. Proposed Changes for 1.1 Beta Modularization oboe-core … the basic structures Entity, Observation, Characteristic, Protocol, Standard, Measurement oboe … the next level of detail Entity (Primitive) Values Characteristics: PhysicalCharacteristic, QualifiedCharacteristic, Name, Type Unit structure: BaseUnit, DerivedUnit, CompositeUnit, UnitConversion oboe-unit … common units & characteristics Physical characteristics (dimensions), conversions, etc.

13. Comparison of OBOE to O&M Highly overlapping models … Observation FeaturePropertyType Time Location ResultDataProcess ObservationCollection featureOfInterestobservedProperty result procedure observationLocation samplingTime member memberOf ObservationContext + role relatedObservation Entity CharacteristicMeasurement Value Protocol Context* Context Observation + Measurement Characteristic