Alignment Ontologies
The Sustainability Ontology grounds every Open Footprint data element in O-DEF semantics. Alignment ontologies extend that grounding outward — mapping our terms to the shared web ontologies the rest of the world queries.
Why Alignments Matter
The virtual knowledge graph answers SPARQL queries over Open Footprint data. Aligning OFP terms to shared ontologies means a units value is also a QUDT unit, a sensor reading is also a SOSA observation, and an evidence chain is also PROV-O lineage — so external tools, auditors, and data consumers can query the graph in vocabularies they already know.
The Alignment Set
The de facto RDF units ontology. Each QUDT unit ships crosswalks to UCUM, UNECE, IEC 61360, OM, and the BIPM SI Digital Framework — six unit systems for the price of one alignment.
Models what was observed, by which sensor, of which feature of interest. The RDF backbone for measurement-based MRV evidence — methane sensors, satellite detections, drone surveys.
Who produced what, derived from what, using which activity. The vocabulary for evidence chains: every attestation, calculation, and source document gets machine-readable lineage.
Geometries, spatial relations, and spatial query functions for SPARQL. Lets the knowledge graph answer which facilities, assets, and observations intersect where.
Legal entities, instruments, and contracts built around the LEI — joins financial-sector semantics to OFP organizations through the same identifier dVeracity verifies via vLEI.
How Alignment Works
Each mapping is a thin, explicit crosswalk — the canonical model never changes, and every external term is reachable from the O-DEF grounding chain.