Composition¶

What every composition is: a list of components, each a constituent with an amount. Both are required here, and what a constituent may be is what the two subschemas fix, ChemicalComposition and MaterialComposition: a chemical species there, another material here. Both spell the term constituent, and each scopes its own context onto it, so one JSON key carries two predicates without either schema restating the list.

module: materials 0.2.0
module version: 0.1 · dev
extended by: ChemicalComposition, MaterialComposition
schema file: /materials/dev/Composition.schema.json
earlier versions: 0.1.0

TermsJSONYAML

Term	Constraints	Consensus mapping	Alternative mappings
`type`	`array`, default `["Composition"]`	`@type`	-
`"Composition"` What every composition is: a list of components, each a constituent with an amount. What a constituent may be is what differs, so the subschemas declare it. Terms in this schema's own IRI space are placeholders for a vocabulary that is not agreed yet, not a third ontology: they carry no axioms, and each records what it means in EMMO and in PMDco.	type alias	https://w3id.org/oo-ld/schemas/materials/0.2/Composition.schema.json	-
`components`	`array`, `items` Component	`comp:/properties/components`	-
`type`	`array`, default `["Component"]`	`@type`	-
`constituent` What the component is made of. Which kind of thing that may be is what a composition fixes: a chemical species, or another material.	`string`	`comp:/$defs/Component/properties/constituent`	-
`amount`	`$ref` MassFraction	`comp:/$defs/Component/properties/amount`	emmo: emmo:hasQuantityPart hasQuantityPart, 1.0.4 only pmdco: pmd:specified by value specified by value
all of QuantityValue
`type`	`array`, default `["QuantityValue"]`	`@type`	-
`value` *	`number`	qudt:value	schemaorg: schema:value pmdco: obo:has specified numeric value
`unit`	`string`, format `iri-reference`	qudt:has unit	schemaorg: schema:unitCode URL branch of schema:unitCode, carrying the QUDT unit IRI pmdco: obo:has measurement unit label closeMatch range is iao:measurement unit label; unit-label vs QUDT-IRI mapping needed emmo: emmo:hasReferencePart hasReferencePart; pinned 1.0.4 branch snapshot (units are individuals there)
`standard_uncertainty` Standard uncertainty, expressed in the unit of value (GUM convention)	`number`	qudt:standard uncertainty	emmo: emmo:standardUncertainty standardUncertainty (VIM4 3.6); 1.0.4 branch only
`relative_standard_uncertainty` Dimensionless ratio, not percent; ratio-scale quantities only, undefined at value 0; redundant with standard_uncertainty (u = r * \|v\|), give only one	`number`	qudt:relative standard uncertainty	-
`type`	default `["MassFraction"]`	`@type`	-
`unit`	enum, default `"percent"`	qudt:has unit	schemaorg: schema:unitCode URL branch of schema:unitCode, carrying the QUDT unit IRI pmdco: obo:has measurement unit label closeMatch range is iao:measurement unit label; unit-label vs QUDT-IRI mapping needed emmo: emmo:hasReferencePart hasReferencePart; pinned 1.0.4 branch snapshot (units are individuals there)
`"percent"`	value alias	qunit:Percent	emmo: emmo:WeightPercent the quantity decides that percent is by mass, so the same alias resolves differently in a VolumeFraction pmdco: obo:mass percentage UO mass percentage
`"part_per_million"`	value alias	qunit:Parts per Million	emmo: emmo:PartPerMillion pmdco: obo:parts per million UO parts per million

* marks a required property.

{
  "$schema": "https://oo-ld.org/latest/meta/oold-meta-schema.json",
  "$id": "Composition.schema.json",
  "x-oold-uuid": "21e7c9d7-bf27-5c8f-a02d-03ae1075d090",
  "x-oold-version": "0.2.0",
  "title": "Composition",
  "description": "What every composition is: a list of components, each a constituent with an amount. What a constituent may be is what differs, so the subschemas declare it. Terms in this schema's own IRI space are placeholders for a vocabulary that is not agreed yet, not a third ontology: they carry no axioms, and each records what it means in EMMO and in PMDco.",
  "type": "object",
  "properties": {
    "type": {
      "type": "array",
      "items": {
        "type": "string"
      },
      "default": [
        "Composition"
      ]
    },
    "components": {
      "type": "array",
      "minItems": 1,
      "items": {
        "$ref": "#/$defs/Component"
      }
    }
  },
  "$defs": {
    "Component": {
      "type": "object",
      "title": "Component",
      "description": "One constituent of a composition and how much of it there is. What may be a constituent is what the subschemas fix: a chemical species, or another material.",
      "properties": {
        "type": {
          "type": "array",
          "items": {
            "type": "string"
          },
          "default": [
            "Component"
          ]
        },
        "constituent": {
          "type": "string",
          "description": "What the component is made of. Which kind of thing that may be is what a composition fixes: a chemical species, or another material."
        },
        "amount": {
          "$ref": "https://w3id.org/oo-ld/schemas/quantities/0.2/MassFraction.schema.json"
        }
      },
      "required": [
        "type",
        "constituent",
        "amount"
      ]
    }
  },
  "@context": [
    "https://w3id.org/oo-ld/schemas/quantities/0.2/MassFraction.schema.json",
    {
      "@version": 1.1,
      "emmo": "https://w3id.org/emmo#",
      "obo": "http://purl.obolibrary.org/obo/",
      "pmd": "https://w3id.org/pmd/co/",
      "qudt": "http://qudt.org/schema/qudt/",
      "qunit": "http://qudt.org/vocab/unit/",
      "qkind": "http://qudt.org/vocab/quantitykind/",
      "schema": "http://schema.org/",
      "comp": {
        "@id": "https://w3id.org/oo-ld/schemas/materials/0.2/Composition.schema.json#",
        "@prefix": true
      },
      "id": "@id",
      "type": {
        "@id": "@type",
        "@container": "@set"
      },
      "Composition": "https://w3id.org/oo-ld/schemas/materials/0.2/Composition.schema.json",
      "Component": "comp:/$defs/Component",
      "components": {
        "@id": "comp:/properties/components",
        "@type": "@id",
        "@container": "@set"
      },
      "constituent": {
        "@id": "comp:/$defs/Component/properties/constituent"
      },
      "amount": {
        "@id": "comp:/$defs/Component/properties/amount",
        "@type": "@id",
        "@context": "https://w3id.org/oo-ld/schemas/quantities/0.2/MassFraction.schema.json"
      }
    }
  ],
  "x-oold-context": {
    "amount": {
      "emmo:EMMO_95d706e4_8b16_48a1_8dfd_40ccd4df1c12": {
        "x-oold-sssom": {
          "predicate_id": "skos:exactMatch",
          "mapping_set_id": "https://w3id.org/oo-ld/schemas/mappings/emmo.sssom.tsv",
          "object_source_version": "https://w3id.org/emmo/1.0.4",
          "comment": "hasQuantityPart, 1.0.4 only"
        }
      },
      "pmd:PMD_0000077": {
        "x-oold-sssom": {
          "predicate_id": "skos:exactMatch",
          "mapping_set_id": "https://w3id.org/oo-ld/schemas/mappings/pmdco.sssom.tsv",
          "comment": "specified by value"
        }
      }
    }
  },
  "required": [
    "components"
  ],
  "$comment": "`components` reaches an object of this same document, so its terms are in scope already and a scoped @context would only name the document being read. OOLD-CMP-5266 permits the flattening for that case; declaring the scope instead makes the embed graph read as cyclic and skips the round-trip checks."
}

$schema: https://oo-ld.org/latest/meta/oold-meta-schema.json
$id: Composition.schema.json
x-oold-uuid: 21e7c9d7-bf27-5c8f-a02d-03ae1075d090
x-oold-version: 0.2.0
title: Composition
description: 'What every composition is: a list of components, each a constituent with an amount. What
  a constituent may be is what differs, so the subschemas declare it. Terms in this schema''s own IRI
  space are placeholders for a vocabulary that is not agreed yet, not a third ontology: they carry no
  axioms, and each records what it means in EMMO and in PMDco.'
type: object
properties:
  type:
    type: array
    items:
      type: string
    default:
    - Composition
  components:
    type: array
    minItems: 1
    items:
      $ref: '#/$defs/Component'
$defs:
  Component:
    type: object
    title: Component
    description: 'One constituent of a composition and how much of it there is. What may be a constituent
      is what the subschemas fix: a chemical species, or another material.'
    properties:
      type:
        type: array
        items:
          type: string
        default:
        - Component
      constituent:
        type: string
        description: 'What the component is made of. Which kind of thing that may be is what a composition
          fixes: a chemical species, or another material.'
      amount:
        $ref: https://w3id.org/oo-ld/schemas/quantities/0.2/MassFraction.schema.json
    required:
    - type
    - constituent
    - amount
'@context':
- https://w3id.org/oo-ld/schemas/quantities/0.2/MassFraction.schema.json
- '@version': 1.1
  emmo: https://w3id.org/emmo#
  obo: http://purl.obolibrary.org/obo/
  pmd: https://w3id.org/pmd/co/
  qudt: http://qudt.org/schema/qudt/
  qunit: http://qudt.org/vocab/unit/
  qkind: http://qudt.org/vocab/quantitykind/
  schema: http://schema.org/
  comp:
    '@id': https://w3id.org/oo-ld/schemas/materials/0.2/Composition.schema.json#
    '@prefix': true
  id: '@id'
  type:
    '@id': '@type'
    '@container': '@set'
  Composition: https://w3id.org/oo-ld/schemas/materials/0.2/Composition.schema.json
  Component: comp:/$defs/Component
  components:
    '@id': comp:/properties/components
    '@type': '@id'
    '@container': '@set'
  constituent:
    '@id': comp:/$defs/Component/properties/constituent
  amount:
    '@id': comp:/$defs/Component/properties/amount
    '@type': '@id'
    '@context': https://w3id.org/oo-ld/schemas/quantities/0.2/MassFraction.schema.json
x-oold-context:
  amount:
    emmo:EMMO_95d706e4_8b16_48a1_8dfd_40ccd4df1c12:
      x-oold-sssom:
        predicate_id: skos:exactMatch
        mapping_set_id: https://w3id.org/oo-ld/schemas/mappings/emmo.sssom.tsv
        object_source_version: https://w3id.org/emmo/1.0.4
        comment: hasQuantityPart, 1.0.4 only
    pmd:PMD_0000077:
      x-oold-sssom:
        predicate_id: skos:exactMatch
        mapping_set_id: https://w3id.org/oo-ld/schemas/mappings/pmdco.sssom.tsv
        comment: specified by value
required:
- components
$comment: '`components` reaches an object of this same document, so its terms are in scope already and
  a scoped @context would only name the document being read. OOLD-CMP-5266 permits the flattening for
  that case; declaring the scope instead makes the embed graph read as cyclic and skips the round-trip
  checks.'

The amount references quantities/MassFraction at its published IRI. The quantity, not the unit, decides that a percentage is by mass, so the same percent reads as emmo:WeightPercent here and would read as emmo:VolumePercent under a volume fraction.

Terms in a schema's own IRI space are placeholders for a vocabulary that is not agreed yet, not a third ontology. They carry no axioms, they dereference to the schema that defines them, and each records in x-oold-context what it means in EMMO and in PMDco. Every schema declares its own prefix, named after itself: the contexts are merged flat, so a shared prefix name would collide and the pointers would land in the wrong file.