http://qudt.org/schema/qudt/SystemOfUnits
<p>A <em>System of Units</em> is a set of units which are chosen as the reference scales for some set of quantity kinds together with the definitions of each unit.
Units may be defined by experimental observation or by proportion to another unit not included in the system.
If the unit system is explicitly associated with a quantity kind system, then the unit system must define at least one unit for each quantity kind.
</p>
Instances of qudt:SystemOfUnits can have the following properties:
| PROPERTY | TYPE | DESCRIPTION | RANGE |
|---|
By the associated SHACL property shapes, instances of qudt:SystemOfUnits can have the following properties:
| PROPERTY | PROPERTY TYPE | DESCRIPTION | MIN | MAX | VALUE TYPE | OTHER CONSTRAINTS | GLOBAL RANGE |
|---|---|---|---|---|---|---|---|
| qudt:SystemOfUnits | |||||||
| qudt:applicablePhysicalConstant | rdf:Property | 0 | * | qudt:PhysicalConstant | -- | ||
| qudt:hasAllowedUnit | rdf:Property | This property relates a unit system with a unit of measure that is not defined by or part of the system, but is allowed for use within the system. An allowed unit must be convertible to some dimensionally eqiuvalent unit that is defined by the system. | 0 | * | qudt:Unit | -- | |
| qudt:hasBaseUnit | rdf:Property | This property relates a system of units to a base unit defined within the system. The base units of a system are used to define the derived units of the system by expressing the derived units as products of the base units raised to a rational power. | 0 | * | qudt:Unit | -- | |
| qudt:hasCoherentUnit | rdf:Property | A coherent unit of measurement for a unit system is a defined unit that may be expressed as a product of powers of the system's base units with the proportionality factor of one. | 0 | * | qudt:Unit | -- | |
| qudt:hasDefinedUnit | rdf:Property | This property relates a unit system with a unit of measure that is defined by the system. | 0 | * | qudt:Unit | -- | |
| qudt:hasDerivedCoherentUnit | rdf:Property | 0 | * | qudt:Unit | -- | ||
| qudt:hasDerivedUnit | rdf:Property | This property relates a system of units to a unit of measure that is defined within the system in terms of the base units for the system. That is, the derived unit is defined as a product of the base units for the system raised to some rational power. | 0 | * | qudt:Unit | -- | |
| qudt:hasUnit | rdf:Property | <p>This property relates a factor unit to its unit or system of units with a unit of measure that is either: </p> <dl> <dd>a) defined by the system,</dd> <dd>b) accepted for use by the system and is convertible to a unit of equivalent dimension that is defined by the system,</dd> <dd>c) a reference to the unit of measure of a quantity (variable or constant) of interest.</dd> </dl> <p>Systems of units may distinguish between base and derived units. Base units are the units which measure the base quantities for the corresponding system of quantities. The base units are used to define units for all other quantities as products of powers of the base units. Such units are called derived units for the system. </p> | 0 | * | qudt:Unit | -- | |
| qudt:prefix | rdf:Property | Associates a unit with the appropriate prefix, if any. | 0 | * | qudt:Prefix | -- | |
| qudt:Concept | |||||||
| dcterms:description | rdf:Property | 0 | * | -- | |||
| dcterms:isReplacedBy | rdf:Property | 0 | 1 | -- | |||
dtype:code |
-- | 0 | * | -- | |||
| qudt:abbreviation | rdf:Property | <p>An abbreviation for a unit is a short ASCII string that is used in place of the full name for the unit in contexts where non-ASCII characters would be problematic, or where using the abbreviation will enhance readability. When a power of abase unit needs to be expressed, such as squares this can be done using abbreviations rather than symbols. For example, <em>sq ft</em> means <em>square foot</em>, and <em>cu ft</em> means <em>cubic foot</em>. </p> | 0 | 1 | xsd:string | -- | |
| qudt:deprecated | rdf:Property | 0 | 1 | xsd:boolean | -- | ||
| qudt:deprecatedInVersion | rdf:Property | Version number of the first QUDT release in which an entity was deprecated. | 0 | 1 | xsd:string |
sh:pattern
^\d+\.\d+\.\d+$
|
-- |
| qudt:exactMatch | owl:ObjectProperty | 0 | * | qudt:Concept | -- | ||
| qudt:guidance | rdf:Property | 0 | * | rdf:HTML | -- | ||
| qudt:hasRule | rdf:Property | 0 | * | qudt:Rule | -- | ||
| qudt:id | rdf:Property | <p>The "qudt:id" is an identifier string that uniquely identifies a QUDT concept. The identifier is constructed using a prefix. For example, units are coded using the pattern: "UCCCENNNN", where "CCC" is a numeric code or a category and "NNNN" is a digit string for a member element of that category. </p> <p>For scaled units there may be an addition field that has the format "QNN" where "NN" is a digit string representing an exponent power, and "Q" is a qualifier that indicates with the code "P" that the power is a positive decimal exponent, or the code "N" for a negative decimal exponent, or the code "B" for binary positive exponents. </p> | 0 | 1 | xsd:string | -- | |
| qudt:plainTextDescription | rdf:Property | A plain text description is used to provide a description with only simple ASCII characters for cases where LaTeX , HTML or other markup would not be appropriate. | 0 | * | -- | ||
rdf:type |
-- | 1 | * | -- | |||
| qudt:Verifiable | |||||||
| qudt:dbpediaMatch | rdf:Property | 0 | * | xsd:anyURI | -- | ||
| qudt:informativeReference | rdf:Property | Provides a way to reference a source that provided useful but non-normative information. | 0 | * |
sh:or
( xsd:anyURI | qudt:Citation )
|
-- | |
| qudt:isoNormativeReference | rdf:Property | Provides a way to reference the ISO unit definition. | 0 | * | xsd:anyURI | -- | |
| qudt:normativeReference | rdf:Property | Provides a way to reference information that is an authoritative source providing a standard definition | 0 | * | xsd:anyURI | -- | |
| qudt:wikidataMatch | rdf:Property | This property relates a QUDT concept to a Wikidata item. The Wikidata item is identified by the Wikidata URI, which is of the form `https://www.wikidata.org/wiki/Q{number}`. | 0 | 1 | -- | ||
@prefix dcterms: <http://purl.org/dc/terms/> .
@prefix qudt: <http://qudt.org/schema/qudt/> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix sh: <http://www.w3.org/ns/shacl#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
qudt:SystemOfUnits a rdfs:Class,
sh:NodeShape ;
rdfs:label "System of Units" ;
dcterms:description """
<p>A <em>System of Units</em> is a set of units which are chosen as the reference scales for some set of quantity kinds together with the definitions of each unit.
Units may be defined by experimental observation or by proportion to another unit not included in the system.
If the unit system is explicitly associated with a quantity kind system, then the unit system must define at least one unit for each quantity kind.
</p>"""^^rdf:HTML ;
qudt:informativeReference "http://dbpedia.org/resource/Category:Systems_of_units"^^xsd:anyURI,
"http://www.ieeeghn.org/wiki/index.php/System_of_Measurement_Units"^^xsd:anyURI ;
rdfs:isDefinedBy <http://qudt.org/3.5.2/schema/shacl/qudt> ;
rdfs:subClassOf qudt:Concept,
qudt:Verifiable ;
sh:property qudt:SystemOfUnits-applicablePhysicalConstant,
qudt:SystemOfUnits-hasAllowedUnit,
qudt:SystemOfUnits-hasBaseUnit,
qudt:SystemOfUnits-hasCoherentUnit,
qudt:SystemOfUnits-hasDefinedUnit,
qudt:SystemOfUnits-hasDerivedCoherentUnit,
qudt:SystemOfUnits-hasDerivedUnit,
qudt:SystemOfUnits-hasUnit,
qudt:SystemOfUnits-prefix .