On the Size Complexity of Non-Returning Context-Free PC Grammar Systems

  title={On the Size Complexity of Non-Returning Context-Free PC Grammar Systems},
  author={Erzs{\'e}bet Csuhaj-Varj{\'u} and Gy{\"o}rgy Vaszil},
Improving the previously known best bound, we show that any recursively enumerable language can be generated with a non-returning parallel communicating (PC) grammar system having six contextfree components. We also present a non-returning universal PC grammar system generating unary languages, that is, a system where not only the number of components, but also the number of productions and the number of nonterminals are limited by certain constants, and these size parameters do not depend on… 
Parallel communicating grammar systems with context-free components are Turing complete for any communication model
This work expands the original construction that showed Turing completeness so that broadcast communication is eliminated at the expense of introducing a significant number of additional, helper component grammars, and shows that CF-PCGS with one-step communication are also Turing complete.
On the Number of Components and Clusters of Non-returning Parallel Communicating Grammar Systems
It is proved that three dynamical clusters are sufficient in general for query symbols in general, which can be interpreted as an improvement in the number of necessary clusters when compared to the case of predefined clusters.
Emergence in Context-Free Parallel Communicating Grammar Systems: What Does and Does not Make a Grammar System More Expressive Than Its Parts
This work investigates the emergent factors that affect the expressiveness of parallel communicating grammar systems (PCGS) with context-free components and introduces the notion of PCGS parse trees, and also some techniques that are potentially useful in developing an algorithm for the elimination of broadcast communication.
Variants of Grammar Systems: Motivations and Problems
This work recapitulates some representative research topics, typical and interesting results, including provocative open problems and rich references, based on the motivation to introduce systems of grammar systems.
Pc Grammar Systems with Clusters of Components
We introduce PC grammar systems where the components form clusters and the query symbols refer to clusters not individual grammars, i.e., the addressee of the query is not precisely identified. We ...


Non-returning PC Grammar Systems Generate Any Recursively Enumerable Language with Eight Context-free Components
We show how to generate any recursively enumerable language with a nonreturning PC grammar system having eight context-free components. This is an improvement of descriptional complexity compared to
On the computational power of context-free PC grammar systems
On the Computational Completeness of Context-Free Parallel Communicating Grammar Systems
Turing Machines with Restricted Memory Access
Grammar Systems: A Grammatical Approach to Distribution and Cooperation
This book investigates two major systems, cooperating distributed grammar systems and parallel communicating grammar systems, which concerns hierarchies with respect to different variants of cooperation, relations with classical formal language theory, syntactic parameters such as the number of components and their size, power of synchronization, and general notions generated from artificial intelligence.
Small Universal Register Machines
  • I. Korec
  • Mathematics
    Theor. Comput. Sci.
  • 1996
Handbook of Formal Languages
This first handbook of formal languages gives a comprehensive up-to-date coverage of all important aspects and subareas of the field.
Computation: Finite and Infinite Machines
From the Preface (See Front Matter for full Preface) Man has within a single generation found himself sharing the world with a strange new species: the computers and computer-like machines.