Further Results on Languages of Membrane Structures
  P systems with active membranes were used to generate languages, in the sense of languages associated with the structure of membrane systems. Here, we analyze the power of P systems with membrane creation and dissolution restricted to elementary membranes, P systems without membrane dissolution operating according to certain output modes. This leads us to characterizations of recursively enumerable languages. 
Rama Raghavan, H. Ramesh, Marian Gheorghe, Shankara Narayanan Krishna
cs.DC cs.FL