PLM — multiplicity of relations

There is a discrepancy between the base standard ISO 10303-214 and the OMG PLM Services 1.0 with respect to the multiplicity of relations. While in AP214 of the template “SET [0:?]” is used, in the PLM Services, especially in the XML platform specific model the template “optional SET [1:?]” is used. Although this mapping may be semantically equal, a problem arises with respect to the automatic translation between ISO 10303-21 files and PLM XML files/streams. Proposed solution: consider revising the mapping of cardinalities of type “optional SET [1:?]” in the PLM (XML) Services into “SET [0:?]”.