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>
Focus nodes of this shape (qudt:SystemOfUnits) can have the following properties:
| PROPERTY | DESCRIPTION | MIN | MAX | VALUE TYPE | OTHER CONSTRAINTS |
|---|---|---|---|---|---|
| qudt:applicablePhysicalConstant | 0 | * | qudt:PhysicalConstant | ||
| qudt:hasAllowedUnit | 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 | 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 | 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 | This property relates a unit system with a unit of measure that is defined by the system. | 0 | * | qudt:Unit | |
| qudt:hasDerivedCoherentUnit | 0 | * | qudt:Unit | ||
| qudt:hasDerivedUnit | 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 | <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 | Associates a unit with the appropriate prefix, if any. | 0 | * | qudt:Prefix |
@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 .