Journal of Computer and System Sciences
Handbook of Formal Languages
Regulated Rewriting in Formal Language Theory
Regulated Rewriting in Formal Language Theory
GP Systems with forbidding context
Fundamenta Informaticae - Membrane computing
The power of communication: P systems with symport/antiport
New Generation Computing
P Systems with Activated/Prohibited Membrane Channels
WMC-CdeA '02 Revised Papers from the International Workshop on Membrane Computing
Membrane Systems with Symport/Antiport Rules: Universality Results
WMC-CdeA '02 Revised Papers from the International Workshop on Membrane Computing
On the Number of Non-terminal Symbols in Graph-Controlled, Programmed and Matrix Grammars
MCU '01 Proceedings of the Third International Conference on Machines, Computations, and Universality
Theoretical Computer Science
From regulated rewriting to computing with membranes: collapsing hierarchies
Theoretical Computer Science
Tissue P systems with channel states
Theoretical Computer Science - Insightful theory
Computation: finite and infinite machines
Computation: finite and infinite machines
On Symport/Antiport P Systems with One or Two Symbols
SYNASC '05 Proceedings of the Seventh International Symposium on Symbolic and Numeric Algorithms for Scientific Computing
Symport/Antiport P Systems with Three Objects Are Universal
Fundamenta Informaticae - Contagious Creativity - In Honor of the 80th Birthday of Professor Solomon Marcus
Tissue p systems with antiport rules and small numbers of symbols and cells
DLT'05 Proceedings of the 9th international conference on Developments in Language Theory
Theoretical Computer Science
Computing with cells: membrane systems-some complexity issues
International Journal of Parallel, Emergent and Distributed Systems
CMC'10 Proceedings of the 11th international conference on Membrane computing
Computational power of symport/antiport: history, advances, and open problems
WMC'05 Proceedings of the 6th international conference on Membrane Computing
Properties of membrane systems
CMC'11 Proceedings of the 12th international conference on Membrane Computing
Hi-index | 0.00 |
We consider P systems with symport/antiport rules and small numbers of symbols and membranes and present several results for P systems with symport/antiport rules simulating register machines with the number of registers depending on the number s of symbols and the number m of membranes. For instance, any recursively enumerable set of natural numbers can be generated (accepted) by systems with s ≥ 2 symbols and m ≥ 1 membranes such that m + s ≥ 6. In particular, the result of the original paper [17] proving universality for three symbols and four membranes is improved (e.g., three symbols and three membranes are sufficient). The general results that P systems with symport/antiport rules with s symbols and m membranes are able to simulate register machines with max{m(s-2),(m-1)(s-1)} registers also allows us to give upper bounds for the numbers s and m needed to generate/accept any recursively enumerable set of k-dimensional vectors of non-negative integers or to compute any partial recursive function f : ℕα →ℕβ. Finally, we also study the computational power of P systems with symport/antiport rules and only one symbol: with one membrane, we can exactly generate the family of finite sets of non-negative integers; with one symbol and two membranes, we can generate at least all semilinear sets. The most interesting open question is whether P systems with symport/antiport rules and only one symbol can gain computational completeness (even with an arbitrary number of membranes) as it was shown for tissue P systems in [1].