13th International Conference on Membrane Computing - MTA Sztaki

D. Sburlan
We introduced a formal system composed by a P system with symbol objects
and multiset rewriting rules Π and a finite state machine with output M which
is able to detect changes in consecutive configurations from a computation of
Π; based on what it detects, M changes its state and produces an output (it
increments, decrements, or performs no action on a register able to store an
integer). We were interested in the computational capabilities of the model.
In this regard, we showed how one can simulate the computation of an ET0L
system using an Observer/Interpreter P system which has as core system a P
system with non-cooperative rules; however, in this case we were not able to
produce as output the same number as the length of the word generated by the
ETOL system (hence we could not give the exact characterization in terms of
computational power). We also proved that when catalytic P systems (with one
catalyst) are used one can generate any recursively enumerable set of numbers.
Several open problems can be formulated for the proposed model. For example
we are interested by the case when purely catalytic P systems are used as
core languages. Another interesting topic regards the computational power of the
model when the cardinality of any observation cannot exceed k, 1 ≤ k ≤ card(O).
In the same line of research one can put a bound on the number of states of M
and study the computational power of the Observer/Interpreter P systems with
respect to these constraints. Yet another interesting idea concerns the possibility
of defining the moments when observations can be performed.
Acknowledgments. The work of the author was supported by a CNCS research
grant/2012, Romanian Ministry of Education, Research, and Innovation.
We would like to thank the anonymous reviewers for their valuable comments.
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