PARALLEL AND DISTRIBUTED DERIVATIONS IN THE SINGLE-PUSHOUT APPROACH

Parallel and distributed derivations are introduced and studied in the single-pushout approach, which models rewriting by pushout constructions in appropriate categories of partial morphisms. We present a categorical framework for this approach in an axiomatic way. Models of this categorical framework are among others: graphs, hypergraphs, relational structures, and algebraic specifications with suitable partial morphisms. Several new results concerning parallelism and distributed parallelism are presented which are even new in the example categories.