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1

Array P Systems and t-Communication

Subramanian K.G., Ali R.M., Nagar A.K., Margenstern M.

Fundamenta Informaticae

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2009

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Vol. 91, nr 1

145-159

EN

The two areas of grammar systems and P systems, which have provided interesting computational models in the study of formal string language theory have been in the recent past effectively linked in [4] by incorporating into P systems, a communication mode called t-mode of cooperating distributed grammar systems. On the other hand cooperating array grammar systems [5] and array P systems [1] have been developed in the context of two-dimensional picture description. In this paper, motivated by the study of [4], these two systems are studied by linking them through the t-communication mode, thus bringing out the picture description power of these systems.

2

Modelling Grammar Systems by Tissue P Systems Working in the Sequential Mode

Freund R., Oswald M.

Fundamenta Informaticae

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2007

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Vol. 76, nr 3

305-323

EN

We consider tissue P systems where rules are applied when moving through a channel from one cell to another one. In a very general manner (i.e., working on arbitrary objects as strings, arrays, graphs, etc.), these tissue P systems equipped with the sequential derivation mode allow for the representation of hybrid co-operating grammar systems using the classic basic derivation modes *,t and ? k,=k, ^(3) k, for k ^(3) 1, as well as the internally hybrid modes ( ^(3) kU` ? l), for k,l Î \mathbbN , k ? l, and (tU` ? k) , ( tU` = k) , (tU` ^(3) k) , for k ^(3) 1. Moreover, we also show how these tissue P systems working in the sequential mode allow for the simulation of random context grammars, too.

3

Dynamic Meaning Membrane Systems: An Application to the Description of Semantic Change

Bel-Enguix G., Jiménez-López M.D.

Fundamenta Informaticae

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2007

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Vol. 76, nr 3

219-237

EN

An application of membrane systems to natural languages study is presented. Specifically, we show how language change can be explained by using a new variant of membrane systems: Dynamic Meaning Membrane Systems (DMMS). By using DMMS, we model the main concepts of semantics and explain the three basic types of changes in meaning: broadening, narrowing and shift. Finally, we relate the membrane systems' application to language evolution with the suggested application of the so-called cultural grammar systems to the same topic. Collaboration between the two frameworks may provide a useful formalism that, due to its naturalness and simplicity, might offer interesting results in a discipline traditionally far away from any formalization.

4

Multigenerative Grammar Systems

Meduna A., Lukas R.

Schedae Informaticae

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2006

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Vol. 15

175-188

EN

This paper presents new models for all recursive enumerable languages. These models are based on multigenerative grammar systems that simultaneously generate several strings in a parallel way. The components of these models are context -free grammars, working in a leftmost way. The rewritten nonterminals are determined by a finite set of nonterminal sequences.

5

Sequential Versus Parallel Grammar Formalisms with Respect to Measures of Descriptional Complexity

Aydin S., Bordihn H.

Fundamenta Informaticae

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2003

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Vol. 55, nr 3,4

243-254

EN

For tabled Lindenmayer systems and their languages, the degree of synchronization and the degree of nondeterminism are well investigated measures of descriptional complexity. In this paper the sequential counterparts of tabled Lindenmayer systems, namely cooperating distributed grammar systems and their pure variant (working in the so-called t-mode of derivation) are treated with respect to these complexity measures. In the pure case, where no distinction between terminal and nonterminal symbols is made, the sequential mechanisms are compared with the parallel ones, investigating whether one mechanism may have a better descriptional complexity than the other one when the same language is described.