OBOE Model Changes
SONet Meeting
June 7-9, 2010
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
Overview of OBOE 1.0 Beta
hasContextRelationship
Context
1..1
*
Relationship
*
*
hasContextObservation
*
*
hasObservationContext hasRelationshipEntity
1..1
1..1
1..1
hasMeasurement
*
1..1 1..1
ofEntity
Observation
measurementFor
hasEntityRelationship
Entity
1..1
*
characteristicOf 1..1
Measurement
+ hasPrecision : decimal
+ hasValue : anySimpleType
*
usesProtocol
*
*
CharacteristicValue
ofCharacteristic
1..1
1..1
Protocol
1..1
hasCharacteristic
Characteristic
usesStandard
1..1
MeasurementStandard
*
*
hasCharacteristicValue
Proposed Changes (OBOE 1.1 Beta)
contextFor
hasContext
*
*
observedBy
Observation
measurementFor
*
ofEntity
Entity
1..1
1..1
1..1
hasValue
hasMeasurement
valueFor
*
Measurement
+ hasPrecision : decimal
+ hasMethod : anyType
protocolFor
usesProtocol
Protocol
1..1
*
*
*
measuredBy
*
standardFor
1..1
usesStandard
Standard
ofCharacteristic
1..1
Characteristic
Overview of OBOE 1.0 Beta
• Entities can have (simple) characteristics
– Similar to OWL data type properties
– Length, Height, Mass, ...
• Values have “value codes” characteristicOf
Entity
1..1
(e.g., Shell)
– Implicit connection to data
(e.g., DamagedValue)
CharacteristicValue
+ hasCode : anySimpleType
hasCharacteristic
Characteristic
(e.g., Condition)
1..1
*
*
hasCharacteristicValue
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
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.)
hasContextRelationship
Context
*
*
hasContextObservation
1..1
Observation
*
1..1
*
hasObservationContext
*
Relationship
hasRelationshipEntity
ofEntity
1..1
*
1..1
Entity
hasEntityRelationship
1..1
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)
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
Overview of OBOE 1.0 Beta
MeasurementStandard
Characteristic
Unit
Dimension
forCharacteristic
BaseUnit
+ hasPower = 1
1..1
BaseDimension
+ hasPower = 1
1..1
hasBaseUnit
hasBaseDimension
*
*
SimpleDerivedUnit
forCharacteristic
+ hasPower = int
SimpleDerivedDimension
+ hasPower = int
U
U
2..*
2..*
hasUnit
hasDimension
forCharacteristic
ComplexDerivedUnit
*
ComplexDerivedDimension
Note: Implicit constraints that must be enforced
by the application (i.e., not by a reasoner)
*
Proposed Changes (OBOE 1.1 Beta)
Characteristic
MeasurementStandard
standardFor o hasCharacteristic
PhysicalCharacteristic
Unit
Characteristics can be used
over a variety of units and
standards … no restriction
on structuring
BaseUnit
1..1
hasUnit
Enables many “surrogates”
for a characteristic (like
density …)
*
DerivedUnit
+ hasPower = int
U
2..*
hasUnit
CompositeUnit
*
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.
Comparison of OBOE to O&M
• Highly overlapping models …
Characteristic
Context*
ObservationCollection
ObservationContext
Context
+ role
Time
memberOf
samplingTime
member
relatedObservation
Observation +
Measurement
featureOfInterest
Feature
Entity
observationLocation
Observation
observedProperty
PropertyType
Characteristic
Location
Context*
result
ResultData
Measurement Value
procedure
Process
Protocol