Technical Report 4.30(I). Progretto Finalizzato Sistemi Informatici e Calcolo Parallelo. Consiglio Nazionale delle Ricerche (CNR), Italy, March 1991.
Abstract: The paper proposes a characterization of the state space of an Elementary Net (EN) system in terms of a relational algebraic struture, called Local State Transformation (LST-) algebra. This latter allows one to take into consideration in an explicit way local state transformations performed by the occurrence of events. A class of injective morphisms between LST-algebas allows one to compare system behaviours at different levels of abstraction and to introduce a notion of preorder on the class of EN systems. Moreover, the class of morphisms allows the definition of a notion of state observability and a notion of equivalence beeween Oberservable Elementary Net Systems.
Keywords: algebraic characterisation (of) elementary net system observable state space; elementary net system preorder; local state transformation; occurrence (of) events; levels (of) abstraction; state observability.