Acta Informatica

, Volume 47, Issue 2, pp 133–146 | Cite as

Small universal accepting hybrid networks of evolutionary processors

  • Remco Loos
  • Florin Manea
  • Victor Mitrana
Original Article


In this paper, we improve some results regarding the size complexity of accepting hybrid networks of evolutionary processors (AHNEPs). We show that there are universal AHNEPs of size 6, by devising a method for simulating 2-tag systems. This result improves the best upper bound for the size of universal AHNEPs which was 7. We also propose a computationally and descriptionally efficient simulation of nondeterministic Turing machines with AHNEPs. More precisely, we prove that AHNEPs with ten nodes can simulate any nondeterministic Turing machine of time complexity f (n) in time O(f (n)). This result significantly improves the best known upper bound for the number of nodes in a network simulating in linear time an arbitrary Turing machine, namely 24.


Turing Machine Input String Hybrid Network Communication Step Input Word 
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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  1. 1.EMBL, European Bioinformatics InstituteHinxton, CambridgeUK
  2. 2.Faculty of Mathematics and Computer ScienceUniversity of BucharestBucharestRomania
  3. 3.Faculty of Computer ScienceOtto-von-Guericke University of MagdeburgMagdeburgGermany
  4. 4.Department of Information Systems and ComputationTechnical University of ValenciaValenciaSpain

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