Browsing by Author "Stokes, Tim E."

Now showing items 16-20 of 34

  • Identities in the Algebra of Partial Maps

    Jackson, Marcel; Stokes, Tim E. (World Scientific Publishing, 2006)
    We consider the identities of a variety of semigroup-related algebras modelling the algebra of partial maps. We show that the identities are intimately related to a weak semigroup deductive system and we show that the ...
  • Joins of subalgebras and normals in 0-regular varieties

    Stokes, Tim E.; McConnell, N. R. (Springer Basel, 2015)
    In any 0-normal variety (0-regular variety in which {0} is a subalgebra), every congruence class containing 0 is a subalgebra. These “normal subalgebras” of a fixed algebra constitute a lattice, isomorphic to its congruence ...
  • Left restriction monoids from left E-completions

    Stokes, Tim E. (Elsevier BV, 2022-05)
    Given a monoid S with E any non-empty subset of its idempotents, we present a novel one-sided version of idempotent completion we call left E-completion. In general, the construction yields a one-sided variant of a small ...
  • Modal restriction semigroups: towards an algebra of functions

    Jackson, Marcel; Stokes, Tim E. (World Science, 2011)
    Restriction semigroups model algebras of partial maps under composition and domain. Here we consider restriction semigroups for which the usual Boolean operations on domains are modeled. Such algebras are capable of modeling ...
  • Monoids with tests and the algebra of possibly non-halting programs

    Jackson, Marcel; Stokes, Tim E. (Elsevier, 2015-03)
    We study the algebraic theory of computable functions, which can be viewed as arising from possibly non-halting computer programs or algorithms, acting on some state space, equipped with operations of composition, if-then-else ...