DTV11 — DTV Issue: Concept terms should not use algebraic symbols

Algebraic symbols (<, <=, =) are incorporated in the terms of various concepts, such as "duration1 < duration2". This causes problems when these concepts are mapped to UML, CLIF, or OWL because these languages restrict the character set of names to alphanumeric characters. You can see this in figure 8.10, where this concept is mapped to the "is less than" method name – probably because OCL does not support the "<" character.

Suggestion: use primary terms that are only alphanumeric, and restrict algebraic symbols to Synonymous Forms. For example, as is already done for "time interval1 is before time interval2".

The RTF agrees that the mathematical symbols should not be the primary terms, in order to simplify mappings to implementation languages that restrict the characters permitted in terms. In each case, the mathematical symbol will be retained as a synonymous form for the verb concept. In addition, the specification of the ‘noun forms’ for the arithmetic verbs is inconsistent; both the sign form and the word form will be specified for both plus and minus.
The revised text also corrects a paragraph labeling error (Issue 19032), and removes a redundant copy of the axioms for the duration ordering.