SA PT/C is defined as folIows: ») bo = ( e ol J ••• J e om t 2l ( ~ .. ~ . ~ . . . . . . . . .. / = me~ge ( merge (Gl(e k),~G2(b . =e . )/b. SISC(b Ok 0 l J J J / l<=k<=rn )! ) / e.
Two questions are open about other relations: a) which is the relation between QI-equivalence and CO-equivalence ? (We conjecture that QI-equivalence is strictly related to co 2-equivalence but a deeper analysis is needed in order to give a definitive answer to this question) • b) Which is the relation between YB-equivalence and CO-equivalence ? (Yoeli and Etzion have already shown that there are some nets that are YB-equiva1ent but are not CO-equivalent (21), any how it remains open the question if CO-equivalence is stronger than YB-equivalence or they are dis joint) .
Applications and Theory of Petri Nets: Selected Papers from the 3rd European Workshop on Applications and Theory of Petri Nets Varenna, Italy, September 27–30, 1982 (under auspices of AFCET, AICA, GI, and EATCS) by C. A. Petri (auth.), Anastasia Pagnoni, Grzegorz Rozenberg (eds.)