4 results
Alexandra Silva ; Marcello Bonsangue ; Jan Rutten.
In this paper, we present a systematic way of deriving (1) languages of (generalised) regular expressions, and (2) sound and complete axiomatizations thereof, for a wide variety of systems. This generalizes both the results of Kleene (on regular languages and deterministic finite automata) and […]
Published on September 9, 2010
Alexandra Silva ; Filippo Bonchi ; Marcello Bonsangue ; Jan Rutten.
The powerset construction is a standard method for converting a nondeterministic automaton into a deterministic one recognizing the same language. In this paper, we lift the powerset construction from automata to the more general framework of coalgebras with structured state spaces. Coalgebra is an […]
Published on March 4, 2013
Jörg Endrullis ; Helle Hvid Hansen ; Dimitri Hendriks ; Andrew Polonsky ; Alexandra Silva.
We present a coinductive framework for defining and reasoning about the infinitary analogues of equational logic and term rewriting in a uniform, coinductive way. The setup captures rewrite sequences of arbitrary ordinal length, but it has neither the need for ordinals nor for metric convergence. […]
Published on January 10, 2018
Harsh Beohar ; Barbara König ; Sebastian Küpper ; Alexandra Silva ; Thorsten Wißmann.
We consider conditional transition systems, that model software product lines with upgrades, in a coalgebraic setting. By using Birkhoff's duality for distributive lattices, we derive two equivalent Kleisli categories in which these coalgebras live: Kleisli categories based on the reader and on the […]
Published on February 28, 2018