An Ontology Design Pattern (ODP) for representing persistent identifiers that maintain stable identity while their referents change over time according to defined rules.
The Temporal Indirection Pattern models situations where stable references point to different entities over time through rule-based transitions. This pattern is fundamental to systems where stable identifiers must persist while their underlying implementations change systematically.
- Persistent Reference: A stable identifier that maintains its identity over time
- Referent Entity: The actual entity being referenced at any given time
- Temporal Binding: The relationship linking a reference to an entity for a specific period
- Transition Event: The moment when one referent changes to another
- Resolution Context: The rules and conventions governing the temporal indirection
Temporal indirection occurs when a persistent identifier maintains stable identity while its referent—the entity it denotes—changes over time according to systematic rules. This creates a two-level reference system: the stable identifier at one level, and the changing referent at another, mediated by time-dependent mapping rules.
Generic tickers like "CL1" (front-month crude oil futures) maintain stable identity while referencing different monthly contracts as they roll. This enables:
- Continuous price tracking across contract transitions
- Automated trading strategies without reconfiguration
- Historical analysis with consistent identifiers
Flight numbers like "UA001" persist while aircraft, crews, and routes change daily, supporting:
- Performance metrics aggregation
- Safety investigation reconstruction
- Maintenance tracking across fleet rotations
- Regulatory compliance reporting
- Healthcare: On-call physician roles, shift assignments, clinical trial protocols
- Transportation: Shipping routes, vehicle fleet management
- Manufacturing: Production line assignments, supplier rotations
- Environmental Monitoring: Sensor station assignments, satellite observation slots
- Digital Services: API endpoint versions, load-balanced server assignments
temporal-indirection-pattern/
├── README.md
├── requirements.txt
├── ontologies/
│ ├── temporal-indirection-pattern.ttl # Core pattern definition
│ ├── temporal-indirection-pattern-dul.ttl # DUL-aligned version
│ ├── financial-derivatives-ontology.ttl # Financial domain specialization
│ └── aviation-operations-ontology.ttl # Aviation domain specialization
├── data/
│ ├── derivatives-instances.ttl # Financial market instances
│ └── aviation-instances.ttl # Aviation operations instances
├── queries/
│ ├── derivatives-competency-questions.sparql # Financial pattern queries
│ └── aviation-competency-questions.sparql # Aviation pattern queries
└── tests/
├── test_pattern_derivatives.py # Financial pattern tests
└── test_pattern_aviation.py # Aviation pattern tests
- Python 3.8+
- RDFLib for RDF/OWL processing
- SPARQL support
# Clone the repository
git clone https://github.com/YuliaS/temporal_indirection.git
cd temporal-indirection-pattern
# Install dependencies
pip install -r requirements.txtpython tests/test_pattern_derivatives.pyExpected output:
Loading ontologies/temporal-indirection-pattern.ttl...
Loading ontologies/financial-derivatives-ontology.ttl...
Loading data/instances.ttl...
Total triples loaded: 400
============================================================
TEMPORAL INDIRECTION PATTERN TEST SUITE
============================================================
TEST RESULTS:
[Table showing all competency questions with PASS status]
Coverage: 100%
Status: ✓ ALL TESTS PASSEDpython tests/test_pattern_aviation.pyExpected output:
Loading ontologies/temporal-indirection-pattern.ttl...
Loading ontologies/aviation-operations-ontology.ttl...
Loading data/aviation-instances.ttl...
Total triples loaded: 467
======================================================================
AVIATION TEMPORAL INDIRECTION PATTERN TEST SUITE
======================================================================
TEST RESULTS:
[Table showing all competency questions with PASS status]
AVIATION SAFETY & COMPLIANCE SUMMARY
✈ Flight Number Tracked: UA001
✈ Total Aircraft Rotations: 3
✈ Total Crew Rotations: 3
✈ Safety Incidents Recorded: 1
✈ Maintenance Events Tracked: 2
✈ Temporal Consistency: ✓ Verified
Coverage: 100%
Status: ✓ ALL TESTS PASSED- ClassDescriptionPersistentReference: Stable identifier maintaining identity over time
- ReferentEntity: The actual entity being referenced
- TemporalBinding: Links reference to entity for a time period
- TransitionEvent: Marks change from one referent to another
- ResolutionContext: Rules governing the temporal indirection
- Convention: Domain-specific rules for transitions
- TransitionRule: Specific rules triggering transitions
- Observation: Observations linked to both reference and referent
- TemporalInterval: Time period with start and end times
- bindsTo: TemporalBinding → ReferentEntity — Links binding to referent
- hasTemporalBinding: PersistentReference → TemporalBinding — Links reference to bindings
- hasTransition: ReferentEntity → TransitionEvent — Links entity to transitions
- hasValidTime: TemporalBinding → TemporalInterval — Valid time period
- observedEntity: Observation → PersistentReference — Persistent reference observed
- observedReferent: Observation → ReferentEntity — Specific referent at observation
The pattern addresses these fundamental questions:
- Current State: What is the current referent for a given persistent reference?
- Historical State: What was the referent at a specific historical timestamp?
- Transitions: When did referent transitions occur?
- Observations: What observations are associated with specific referents?
- Complete History: What is the complete history of referents?
- Transition Rules: What rules triggered specific transitions?
- Temporal Consistency: Are there gaps or overlaps in temporal bindings?
- Domain-Specific: (Financial) Spread relationships, (Aviation) Safety investigations
Demonstrates generic ticker persistence (CL1, CL2) for futures contracts:
- Monthly contract rolls
- Calendar spread tracking
- Price observation attribution
- Exchange convention compliance
Demonstrates flight number persistence (UA001) with changing operations:
- Daily aircraft rotations
- Crew assignment tracking
- Performance metrics aggregation
- Safety incident investigation
- Maintenance event correlation
SELECT ?referent WHERE {
:PersistentID :hasTemporalBinding ?binding .
?binding :bindsTo ?referent ;
:hasValidTime ?period .
?period :hasStartTime ?start ;
:hasEndTime ?end .
FILTER(NOW() >= ?start && NOW() < ?end)
}SELECT ?referent ?time WHERE {
:PersistentID :hasTemporalBinding ?binding .
?binding :bindsTo ?referent ;
:hasValidTime ?period .
?period :hasStartTime ?time .
FILTER(?time <= "2024-08-14T12:00:00Z"^^xsd:dateTime)
}
ORDER BY DESC(?time) LIMIT 1We welcome contributions! Please see our contributing guidelines for:
- Adding new domain specializations
- Extending competency questions
- Improving test coverage
- Documentation enhancements
- Create domain ontology in
ontologies/ - Add instance data in
data/ - Write competency questions in
queries/ - Implement test suite in
tests/ - Update documentation
For detailed pattern description and theoretical foundation, see:
- Paper Title: "An Ontology Design Pattern for Representing Temporal Indirection"
Authors: Yulia Svetashova
Conference/Journal: TBA Year: 2025
- Track rolling futures positions
- Maintain continuous price histories
- Automate contract roll procedures
- Calculate spread relationships
- Reconstruct operational context for incidents
- Track maintenance across fleet
- Analyze crew performance patterns
- Ensure regulatory compliance
- Manage on-call physician schedules
- Track patient observations across shifts
- Maintain treatment continuity
- Audit clinical decisions
- Recurrent Situation Series: For modeling periodic recurring situations
- Observation Pattern: For linking observations to entities
- Time Indexed Situation: For situations with temporal extent
- Role Pattern: For modeling roles independent of their players
- Issues: GitHub
- Email: svetashova@gmail.com
- Pattern Portal: OntologyDesignPatterns.org
If you use this pattern in your research, please cite:
@inproceedings{temporal-indirection-2024,
title={An Ontology Design Pattern for Temporal Indirection},
author={Svetashova, Yulia},
booktitle={TBA},
year={2025},
pages={xx-xx}
}