H2KG Ontology

Release

EMMO-aligned ontology for hydrogen electrochemical systems, experiments, materials, measurements, and FAIR metadata

H2KG Ontology logoOntology release

Developed through DECODE, the Helmholtz Metadata Collaboration (HMC), and AIMWORKS to support FAIR ontology publication and reusable metadata infrastructure for hydrogen electrochemical systems.

HMCAIMWORKS

Release Readiness

FAIR signals on this page follow a public-first policy: local build artefacts improve readiness, but full findability and accessibility require publicly established publication infrastructure. External OOPS! and FOOPS! results are reported separately as observability signals so service outages do not masquerade as ontology quality.

The detailed quality and transparency view is published on the Quality Dashboard.

FAIR Snapshot

  • 100/100 Findable
  • 100/100 Accessible
  • 100/100 Interoperable
  • 90/100 Reusable

AIMWORKS Artifacts

  • Public release artefacts are established and synchronized with the current resolver-backed publication.

ODK Release Artefacts

ODK artefacts are now promoted and serve as the accepted machine release surface for comparison, QC, and downstream tooling.

Base ontology

Actual ODK base artefact generated from the nested workbench.

Generated: 2026-04-24T10:17:21+00:00 | Size: 7487232 bytes

OWLTTLJSON-LD

Full ontology

Actual ODK full artefact with import closure or broader release surface.

Generated: 2026-04-24T10:17:21+00:00 | Size: 2346668 bytes

OWL

Simple ontology

Actual ODK simple artefact for tooling that prefers a smaller release view.

Generated: 2026-04-24T10:17:21+00:00 | Size: 24564 bytes

OWL

ODK Release Status

  • Current authority: AIMWORKS pipeline
  • ODK status: promoted
  • Reasoner: ELK
  • ODK version: prepared only
  • Parity: aligned

ODK artefacts are technically aligned, show no IRI drift, and have been explicitly promoted out of shadow mode.

  • Import stability WATCH follow-up
    Required imports are configured and surfaced through the nested ODK workbench.
  • Parity accepted GOOD aligned
    ODK base artefact currently matches the curated schema and vocabulary baseline closely enough for shadow-mode review.
  • Collected base artefact completeness GOOD complete
    The collected ODK base artefact contains the expected local schema terms.
  • Reproducible CI build GOOD good
    GitHub Actions workflows include the full ODK prepare, build, collect, and release sequence needed to reproduce the shadow build in CI.
  • No IRI drift GOOD none
    No local H2KG IRI drift was detected between the curated release and the parity comparison target.
  • Promotion readiness WATCH promoted
    Promotion was requested, but one or more technical shadow-mode gates are still not satisfied.

Publication Establishment

  • Overall publication status GOOD published
    This is the canonical release-state signal for whether the current ontology publication is treated as publicly established.
  • Resolver status GOOD established
    The public resolver status tracks whether the ontology namespace is established through the configured persistent identifier service.
  • Documentation publication status GOOD published
    Documentation publication tracks whether the human-readable HTML documentation is publicly established as part of the current release.
  • Machine artefact publication status GOOD published
    Machine artefact publication tracks whether the ontology serializations and release bundle are treated as publicly established release artifacts.

ODK and HDO Integration

  • HDO import status: placeholder-after-refresh
  • Last refresh: placeholder refresh output at 1777025536.2343504
  • Included in current ODK build: yes
  • HDO-reviewed local terms: 96
  • Aligned to HDO: 5

HDO is the primary alignment source for data, metadata, digital-object, information-profile, identifier, schema, and validation concepts in H2KG.

Direct HDO term reuse becomes stronger when a real HDO cache file is available at cache/sources/hdo.ttl.