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+@prefix aec3po: <https://w3id.org/lbd/aec3po/> .
+@prefix cc: <http://creativecommons.org/ns#> .
+@prefix dct: <http://purl.org/dc/terms/> .
+@prefix owl: <http://www.w3.org/2002/07/owl#> .
+@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
+@prefix skos: <http://www.w3.org/2004/02/skos/core#> .
+@prefix vann: <http://purl.org/vocab/vann/> .
+@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
+
+aec3po:check_method_operators a owl:Ontology ;
+    cc:license <https://creativecommons.org/licenses/by/4.0/> ;
+    dct:contributor aec3po:amna ;
+    dct:description "Definition of operators scheme for AEC3PO."@en ;
+    dct:modified "2023-09-25"^^xsd:date ;
+    dct:title "AEC3PO: Operators"@en ;
+    vann:preferredNamespacePrefix "aec3po" ;
+    vann:preferredNamespaceUri "https://w3id.org/lbd/aec3po/" .
+    
+aec3po:CheckMethodOperator a owl:Class ;
+    rdfs:label "check method operator"@en ;
+    rdfs:comment "Formally defined as the set of skos:Concept in concept scheme aec3po:CheckMethodOperatorNomenclature"@en ;
+    rdfs:isDefinedBy aec3po:check_method_operators ;
+    rdfs:subClassOf skos:Concept,
+        aec3po:CheckMethod ;
+    owl:equivalentClass [ owl:intersectionOf ( skos:Concept [ a owl:Restriction ;
+                        owl:hasValue aec3po:CheckMethodOperatorNomenclature ;
+                        owl:onProperty skos:inScheme ] ) ] .
+
+aec3po:CheckMethodOperatorNomenclature a skos:ConceptScheme ;
+    rdfs:label "check method nomenclature"@en ;
+    rdfs:isDefinedBy aec3po:check_method_operators ;
+    skos:definition """A set of operators for the check method.
+  AEC3PO includes a set of operators for this nomenclature.
+  These operators are :
+  - _eq : equal-to operator;
+  - operator_neq : not equal-to operator.
+  - operator_lt : less-than operator.
+  - operator_le : less-equal operator.
+  - operator_gt : greater-than operator.
+  - operator_ge : greater-equal operator.
+  - operator_exists : exists operator.
+  - operator_notExists : not-exists operator.
+  - operator_forall : forall operator."""@en ;
+    skos:hasTopConcept aec3po:CheckMethodOperator-eq, 
+        aec3po:CheckMethodOperator-neq, 
+        aec3po:CheckMethodOperator-lt, 
+        aec3po:CheckMethodOperator-le, 
+        aec3po:CheckMethodOperator-gt,
+        aec3po:CheckMethodOperator-ge,
+        aec3po:CheckMethodOperator-exists,
+        aec3po:CheckMethodOperator-notExists,
+        aec3po:CheckMethodOperator-forall.
+
+aec3po:CheckMethodOperator-eq a owl:NamedIndividual, skos:Concept,
+        aec3po:CheckMethodOperator ;
+    rdfs:isDefinedBy aec3po:check_method_operators ;
+    skos:definition "equal-to operator."@en ;
+    skos:inScheme aec3po:CheckMethodOperatorNomenclature ;
+    skos:prefLabel "equal-to"@en ;
+    skos:topConceptOf aec3po:CheckMethodOperatorNomenclature .
+
+aec3po:CheckMethodOperator-neq a owl:NamedIndividual, skos:Concept,
+        aec3po:CheckMethodOperator ;
+    rdfs:isDefinedBy aec3po:check_method_operators ;
+    skos:definition "not equal-to operator."@en ;
+    skos:inScheme aec3po:CheckMethodOperatorNomenclature ;
+    skos:prefLabel "not equal-to"@en ;
+    skos:topConceptOf aec3po:CheckMethodOperatorNomenclature .
+
+aec3po:CheckMethodOperator-lt a owl:NamedIndividual, skos:Concept,
+        aec3po:CheckMethodOperator ;
+    rdfs:isDefinedBy aec3po:check_method_operators ;
+    skos:definition "less-than operator."@en ;
+    skos:inScheme aec3po:CheckMethodOperatorNomenclature ;
+    skos:prefLabel "less than"@en ;
+    skos:topConceptOf aec3po:CheckMethodOperatorNomenclature .
+
+aec3po:CheckMethodOperator-le a owl:NamedIndividual, skos:Concept,
+        aec3po:CheckMethodOperator ;
+    rdfs:isDefinedBy aec3po:check_method_operators ;
+    skos:definition "less-equal operator."@en ;
+    skos:inScheme aec3po:CheckMethodOperatorNomenclature ;
+    skos:prefLabel "less equal"@en ;
+    skos:topConceptOf aec3po:CheckMethodOperatorNomenclature .
+
+aec3po:CheckMethodOperator-gt a owl:NamedIndividual, skos:Concept,
+        aec3po:CheckMethodOperator ;
+    rdfs:isDefinedBy aec3po:check_method_operators ;
+    skos:definition "greater-than operator."@en ;
+    skos:inScheme aec3po:CheckMethodOperatorNomenclature ;
+    skos:prefLabel "greater than"@en ;
+    skos:topConceptOf aec3po:CheckMethodOperatorNomenclature .
+
+aec3po:CheckMethodOperator-ge a owl:NamedIndividual, skos:Concept,
+        aec3po:CheckMethodOperator ;
+    rdfs:isDefinedBy aec3po:check_method_operators ;
+    skos:definition "greater-equal operator."@en ;
+    skos:inScheme aec3po:CheckMethodOperatorNomenclature ;
+    skos:prefLabel "greater equal"@en ;
+    skos:topConceptOf aec3po:CheckMethodOperatorNomenclature .
+
+aec3po:CheckMethodOperator-exists a owl:NamedIndividual, skos:Concept,
+        aec3po:CheckMethodOperator ;
+    rdfs:isDefinedBy aec3po:check_method_operators ;
+    skos:definition "exists operator."@en ;
+    skos:inScheme aec3po:CheckMethodOperatorNomenclature ;
+    skos:prefLabel "exists"@en ;
+    skos:topConceptOf aec3po:CheckMethodOperatorNomenclature .
+
+aec3po:CheckMethodOperator-notExists a owl:NamedIndividual, skos:Concept,
+        aec3po:CheckMethodOperator ;
+    rdfs:isDefinedBy aec3po:check_method_operators ;
+    skos:definition "not exists operator."@en ;
+    skos:inScheme aec3po:CheckMethodOperatorNomenclature ;
+    skos:prefLabel "not exists"@en ;
+    skos:topConceptOf aec3po:CheckMethodOperatorNomenclature .
+
+aec3po:CheckMethodOperator-forall a owl:NamedIndividual, skos:Concept,
+        aec3po:CheckMethodOperator ;
+    rdfs:isDefinedBy aec3po:check_method_operators ;
+    skos:definition "forall operator."@en ;
+    skos:inScheme aec3po:CheckMethodOperatorNomenclature ;
+    skos:prefLabel "forall"@en ;
+    skos:topConceptOf aec3po:CheckMethodOperatorNomenclature .
+
+aec3po:CheckMethodOperator-logicalAND a owl:NamedIndividual, skos:Concept,
+        aec3po:CheckMethodOperator ;
+    rdfs:isDefinedBy aec3po:check_method_operators ;
+    skos:definition "logical AND operator."@en ;
+    skos:inScheme aec3po:CheckMethodOperatorNomenclature ;
+    skos:prefLabel "logicalAND"@en ;
+    skos:topConceptOf aec3po:CheckMethodOperatorNomenclature .
+
+aec3po:CheckMethodOperator-logicalOR a owl:NamedIndividual, skos:Concept,
+        aec3po:CheckMethodOperator ;
+    rdfs:isDefinedBy aec3po:check_method_operators ;
+    skos:definition "logical OR operator."@en ;
+    skos:inScheme aec3po:CheckMethodOperatorNomenclature ;
+    skos:prefLabel "logicalOR"@en ;
+    skos:topConceptOf aec3po:CheckMethodOperatorNomenclature .
+
+aec3po:CheckMethodOperator-multiplication a owl:NamedIndividual, skos:Concept,
+        aec3po:CheckMethodOperator ;
+    rdfs:isDefinedBy aec3po:check_method_operators ;
+    skos:definition "multiplication Operator."@en ;
+    skos:inScheme aec3po:CheckMethodOperatorNomenclature ;
+    skos:prefLabel "multiplication"@en ;
+    skos:topConceptOf aec3po:CheckMethodOperatorNomenclature .
+
+aec3po:CheckMethodOperator-division a owl:NamedIndividual, skos:Concept,
+        aec3po:CheckMethodOperator ;
+    rdfs:isDefinedBy aec3po:check_method_operators ;
+    skos:definition "division Operator."@en ;
+    skos:inScheme aec3po:CheckMethodOperatorNomenclature ;
+    skos:prefLabel "division"@en ;
+    skos:topConceptOf aec3po:CheckMethodOperatorNomenclature .
+
+aec3po:CheckMethodOperator-addition a owl:NamedIndividual, skos:Concept,
+        aec3po:CheckMethodOperator ;
+    rdfs:isDefinedBy aec3po:check_method_operators ;
+    skos:definition "addition operator."@en ;
+    skos:inScheme aec3po:CheckMethodOperatorNomenclature ;
+    skos:prefLabel "addition"@en ;
+    skos:topConceptOf aec3po:CheckMethodOperatorNomenclature .
+
+aec3po:hasOperator a owl:FunctionalProperty,
+        owl:ObjectProperty ;
+    rdfs:label "has operator"@en ;
+    rdfs:comment """The operator of a feature of interest or a property of that is needed by the check method.
+  A set of operators is defined by aec3po in the corresponding concept scheme."""@en ;
+    rdfs:isDefinedBy aec3po:check_method_Operators ;
+    rdfs:range aec3po:CheckMethod ;
+    rdfs:subPropertyOf aec3po:hasDesign .