The paper considers some elements of the calculation systems as functional objects. The formal foundations of calculus of systems proposed by the authors were preceded by research on the development of a mathematical apparatus that allows formalizing the procedures for developing system-object simulation models of processes and systems. In the work, the previously developed formal apparatus is supplemented by the context operator, and some theorems related to the structural and functional characteristics of the modeled objects are formulated and proved. In particular, using the context operator, the statement is proved that the connection of a nodal object with the external environment generates the same connections of other nodal objects whose functions are realized due to the functions of the first nodal object
