The optional normalized attribute shows if the spline surface is normalized. A value of 1 (or true) means the surface is normalized. A value of 0 (or false) means the surface is not normalized.
Source
<xs:element name="Spline23Core" type="Spline23CoreType" substitutionGroup="SurfaceCore"><xs:annotation><xs:documentation>The global Spline23Core element is the mathematical core of a spline surface.</xs:documentation></xs:annotation></xs:element>