Definition from ISO/CD 10303-41:1992: A derived unit element is one of the unit quantities
which makes up a derived unit.
EXAMPLE: Newtons per square millimetre is a derived unit.
It has two elements, Newton whose exponent has a value of 1 and millimetre whose exponent is -2.
NOTE Corresponding STEP name: derived_unit_element, please refer to ISO/IS 10303-41:1994
for the final definition of the formal standard.
HISTORY New entity in IFC Release 1.5.1.
|| The fixed quantity which is used as the mathematical factor.
|| The power that is applied to the unit attribute.