@prefix rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix owl: <http://www.w3.org/2002/07/owl#>.
@prefix o2:  <http://www.w3.org/2007/ont/o2#>.   # Just for 'chain' missing from owl

@prefix cc:     <http://creativecommons.org/ns#>.
@prefix dc:	<http://purl.org/dc/elements/1.1/>.
@prefix doc:	<http://www.w3.org/2000/10/swap/pim/doc#> .
@prefix ldif:	<http://www.w3.org/2007/ont/ldif#> .
@prefix :	<http://www.w3.org/2007/ont/unit#> .
@prefix un:	<http://www.w3.org/2007/ont/unit#> . # Hint

@keywords a, is, of.

<>  doc:version "$Id: unit.n3,v 1.5 2007/07/31 23:06:23 timbl Exp $";
    dc:title "An Ontology for Units of Measure";
    doc:creator <http://www.w3.org/People/Berners-Lee/card#i>;
    cc:licence <http://www.w3.org/2000/10/swap/LICENSE.n3>;
    rdfs:comment """Units of Measure.
    
    This ontology defines a set of properties which may be used
    for reprenting physical quantities.   Each is an RDF Property
    which realtes a quantity to a number which expreses the quantity in 
    that expressed that quntity in the given unit.
    
        :bed     ex:length   _:a.
        _a:     m   2.
        
    Property chaining is the equivalent of unit multiplication.
    Inverse properties correspond to reciprocal units.
    Because conventional signs for units are very case-sensitive, this
    ontology breaks from the normal convention that all property localnames
    begin with lowercase.
    See also http://www-ksl.stanford.edu/knowledge-sharing/papers/engmath.html
    """.

Quantity a rdfs:Class;
    rdfs:label "quantity";
    rdfs:comment """A (scalar) physical quanity or dimensionless number.
    (This could be extended to include vector quantities.)""".

Unit a rdfs:Class;
    rdfs:subClassOf rdf:Property;
    rdfs:label "Unit"@en;
    rdfs:comment """Unit of measure.  Units of measure are commutative
    with each other under o2:chain. """.

#  Four units which arbirarily but frequently are used as a 
#  core set.

m a rdf:Property, Unit;
    rdfs:label "m";
    rdfs:domain Quantity; rdfs:range Quantity; 
    rdfs:comment "The number of meters in this linear measurement.".

s a rdf:Property, Unit;
    rdfs:label "s";
    rdfs:domain Quantity; rdfs:range Quantity; 
    rdfs:comment "The number of seconds in this time measurement.".

kg a rdf:Property, Unit;
    rdfs:label "kg";
    rdfs:domain Quantity; rdfs:range Quantity; 
    rdfs:comment "The number of kilograms in this mass.".
    
A a rdf:Property, Unit;
    rdfs:label "A";
    rdfs:domain Quantity; rdfs:range Quantity; 
    rdfs:comment "The number Ampêres in this current.".

# __________________________________

hz a rdf:Property, Unit;
    rdfs:label "Hz";
    rdfs:domain Quantity; rdfs:range Quantity; 
    owl:inverseOf s;
    rdfs:comment "The number of Hertz in this frequency.".

mps a rdf:Property, Unit;
    rdfs:label "ms-1";
    rdfs:domain Quantity; rdfs:range Quantity; 
    is o2:chain of  (m hz);
    rdfs:comment "The number of meters per second in this speed.".

mpsps a rdf:Property, Unit;
    rdfs:label "ms-2";
    rdfs:domain Quantity; rdfs:range Quantity; 
    is o2:chain of  (mps hz);
    rdfs:comment "The number of meters per second per second in this acceleration.".

m2 a rdf:Property, Unit;
    rdfs:label "m2";
    rdfs:domain Quantity; rdfs:range Quantity; 
    is o2:chain of  (m m);
    rdfs:comment "The number of square meters in this area.".

N a rdf:Property, Unit;
    rdfs:label "N";
    rdfs:domain Quantity; rdfs:range Quantity; 
    is o2:chain of  (kg mpsps);
    rdfs:comment "The number of Newtons in this force.".

J a rdf:Property, Unit;
    rdfs:label "J";
    rdfs:domain Quantity; rdfs:range Quantity; 
    is o2:chain of  (N m);
    is o2:chain of  (W s);
    rdfs:comment "The number of joules in this energy.".

W a rdf:Property, Unit;
    rdfs:label "N";
    rdfs:domain Quantity; rdfs:range Quantity; 
    is o2:chain of (A V);
    rdfs:comment "The number of Watts in this power.".

C a rdf:Property, Unit;
    rdfs:label "C";
    rdfs:domain Quantity; rdfs:range Quantity; 
    is o2:chain of (A s);
    rdfs:comment "The number of Coulonbs in this electyric charge.".

V a rdf:Property, Unit;
    rdfs:domain Quantity; rdfs:range Quantity; 
    rdfs:label "V";
    rdfs:comment "The number of Volts in this electrical potential.".


#___________________________ Multiplication with Numbers

product a rdf:Property;
    rdfs:label "product";
    # rdfs:domain ListOfQuantity;
    rdf:range Quanity;
    rdfs:comment "The product of units of measure and numbers.".
    
(m m 10000) product hectare.

(m 0.0254) product inch.
(inch 12) product foot.
(foot 3) product yard.
(yard 22) product chain.
(chain 10) product furlong.
(furlong 8)product mile.
 

# ends