https://build.fhir.org/ig/HL7/fhir-extensions/StructureDefinition-cqf-directReferenceCode.profile.xml.html
HL7.FHIR.UV.EXTENSIONS\Direct reference code - XML Representation - FHIR v5.0.0
reference codefhiruvextensionsdirect
https://directrep.org/
Direct Representation
directrepresentation
https://se.mathworks.com/help/sps/ref/pmsmdq0.html
PMSM (DQ0) - Direct-quadrature-zero representation of permanent magnet synchronous machine - MATLAB
The PMSM (DQ0) block models the direct-quadrature-zero (dq0) frame representation of a permanent magnet synchronous motor (PMSM) with a three-phase stator.