(Fénix Editora, 2006) Besozzi, Daniela; Busi, Nadia; Franco, Giuditta; Freund, Rudolf; Paun, Gheorghe; Universidad de Sevilla. Departamento de Ciencias de la Computación e Inteligencia Artificial; Universidad de Sevilla. TIC193: Computación Natural
We prove that P systems with mate and drip operations and using at most
five membranes during any step of a computation are universal. This improves a recent
similar result from, where eleven membranes are used. The proof of this result has the
"drawback" that the output of a computation is obtained on an inner membrane of the
system. A universality proof is then given for the case when the result of a computation is
found on the skin membrane (on its external side, hence "visible" from the environment),
but in this case we use one more membrane, as well as another basic brane operation
exo; moreover, the operations are now of the projective type, as introduced in.
