Ctrlk
Home
For the complete documentation index, see llms.txt. This page is also available as Markdown.

Ontologies

Appendix C. Sample GRIx Ontologies & Schemas

This appendix provides illustrative, non-normative examples of the GRIx (Global Risk & Resilience Index) ontologies and schemas used within the Nexus Ecosystem. The purpose is to show:

  • How core concepts of risk, resilience, and systems are represented.

  • How domain extensions (e.g., drought–food security, coastal flood–urban infrastructure) plug into the core.

  • How chronotope (time–space–context) and episode schemas structure events and decisions.

All examples are simplified; real deployments would use richer OWL/JSON-LD schemas, full SHACL/SHEx constraints, and alignment with external vocabularies.

C.1 GRIx Core Ontology (Sketch)

At the highest level, GRIx defines a small set of core entity and relationship types for systemic risk:

  • Hazard / Stressors

  • Exposed units and systems

  • Impacts and losses

  • Interventions and decisions

  • Indices and indicators

C.1.1 Core Entities (YAML Sketch)

grix_core:
  version: "1.0.0"
  namespace: "https://nexus.global/grix/core#"

  entities:
    - id: "grix.HazardEvent"
      label: "Hazard Event"
      description: "Realised or simulated occurrence of a physical, biological, cyber, financial, or social hazard."
      attributes:
        - name: "hazard_type"
          type: "string"
          enum: ["drought", "flood", "heatwave", "cyclone", "pandemic", "cyber_attack", "market_shock", "civil_unrest", "multi_hazard"]
        - name: "intensity_metric"
          type: "string"
          description: "Metric used to quantify intensity (e.g., SPI, wind_speed, peak_rainfall, R0)."
        - name: "intensity_value"
          type: "float"
        - name: "return_period_years"
          type: "float"
          nullable: true
        - name: "onset_time"
          type: "datetime"
        - name: "end_time"
          type: "datetime"
        - name: "spatial_footprint"
          type: "geometry"
        - name: "source_system"
          type: "string"
          description: "Producing model or observation system (INT module)."

    - id: "grix.ExposureUnit"
      label: "Exposure Unit"
      description: "Unit that can be affected by hazards (e.g., household, asset, facility, ecosystem unit)."
      attributes:
        - name: "unit_type"
          type: "string"
          enum: ["household", "farm", "substation", "hospital", "school", "bridge", "company", "ecosystem_patch"]
        - name: "location"
          type: "geometry"
        - name: "admin_unit_id"
          type: "string"
        - name: "population"
          type: "integer"
          nullable: true
        - name: "economic_value_usd"
          type: "float"
          nullable: true
        - name: "vulnerability_class"
          type: "string"
          nullable: true

    - id: "grix.SystemNode"
      label: "System Node"
      description: "Node within an infrastructure, economic, or social network (e.g., grid node, hospital, trading hub)."
      attributes:
        - name: "system_type"
          type: "string"
          enum: ["power_grid", "transport_network", "health_system", "water_network", "financial_system", "supply_chain"]
        - name: "node_role"
          type: "string"
          enum: ["source", "hub", "sink", "bridge", "redundant"]
        - name: "capacity"
          type: "float"
          nullable: true
        - name: "criticality_score"
          type: "float"
          range: [0.0, 1.0]

    - id: "grix.ImpactRecord"
      label: "Impact Record"
      description: "Observed or modelled impact on exposure units and systems due to one or more hazard events."
      attributes:
        - name: "impact_type"
          type: "string"
          enum: ["mortality", "morbidity", "economic_loss", "service_disruption", "displacement", "ecological_damage"]
        - name: "value"
          type: "float"
        - name: "unit"
          type: "string"
        - name: "reference_period"
          type: "string"
          description: "Time window of impact measurement, e.g., 'event', 'year', 'season'."

    - id: "grix.Index"
      label: "Index"
      description: "Composite indicator summarising risk, resilience, stress, or equity."
      attributes:
        - name: "index_id"
          type: "string"
        - name: "index_type"
          type: "string"
          enum: ["risk", "resilience", "systemic_stress", "equity", "exposure"]
        - name: "value"
          type: "float"
        - name: "scale"
          type: "string"
          enum: ["local", "subnational", "national", "regional", "global", "portfolio"]
        - name: "calculation_time"
          type: "datetime"
        - name: "method_ref"
          type: "string"
          description: "Reference to method/model card used."

    - id: "grix.Decision"
      label: "Decision"
      description: "Formal decision that materially responds to risk evidence (e.g., facility trigger, budget reallocation, regulatory change)."
      attributes:
        - name: "decision_id"
          type: "string"
        - name: "decision_type"
          type: "string"
          enum: ["capital_trigger", "budget_allocation", "policy_change", "operational_action"]
        - name: "deciding_body"
          type: "string"
        - name: "decision_time"
          type: "datetime"
        - name: "jurisdiction"
          type: "string"
        - name: "nr m_profile_id"
          type: "string"
          description: "NRM Profile under which decision is framed."

C.1.2 Core Relationships

C.2 Domain Extension 1: Drought & Food Security (GRIx–Drought–Food)

This extension is consistent with the East Africa Drought & Food Security Rail in Appendix B.

C.2.1 Entities

C.2.2 Relationships

C.3 Domain Extension 2: Coastal Flood & Urban Infrastructure (GRIx–Coastal–Urban)

Aligned with the Coastal Flood & Urban Infrastructure NRM Pack in Appendix B.

C.3.1 Entities

C.3.2 Relationships

C.4 Chronotope Schema (Time–Space–Context Model)

Chronotope schemas encode how indices, AEPs, and decisions are anchored in time, space, and institutional context.

C.5 Episode Schema (Signals → Decisions → Actions → Outcomes)

Episodes are the main unit of learning in the Chronotope & Episodic Memory Fabric.

C.6 AEP Structural Schema (High-Level)

Finally, a simplified skeleton of an AEP schema showing how GRIx ontologies are used inside a pack of evidence.

These sample ontologies and schemas demonstrate how GRIx provides a unified semantic fabric across hazards, sectors, and scales, and how domain packs extend that fabric without breaking interoperability. In the full whitepaper, these examples can be expanded into:

  • Machine-readable OWL/Turtle and JSON-LD artefacts.

  • SHACL/SHEx shapes for validation.

  • Mapping tables to external vocabularies (e.g., INSPIRE, HL7, ISO TC211, OGC).

so that implementers can move directly from conceptual design to concrete, verifiable implementations on the Nexus Rail.

PreviousYAML
NextAEPs

Last updated

Was this helpful?