P systems with active membranes using only two electrical charges and only rules of types (a) and (c) assigned to at most two membranes are shown to be computationally complete { thus improving the previous result of ...

In the last time, several e®orts were made in order to remove the polarization of membranes from P systems with active membranes; the present paper is a contribution in this respect. In order to compensate the loss of ...

In search for small universal computing devices of various types, we consider here the case of spiking neural P systems (SN P systems), in two versions: as devices computing functions and as devices generating sets of ...

We briefly investigate the idea to consider as the result of a computation in a P system the number of steps elapsed between two events produced during the computation. Specifically, we first consider the case when the ...

We give a direct and simple proof of the equality of Parikh images of lan- guages generated by matrix grammars with appearance checking with the sets of vectors generated by register machines. As a particular case, we ...

With a motivation related to gene expression, where enzymes act in series, somewhat similar to the train spikes traveling along the axons of neurons, we consider an extension of spiking neural P systems, where several ...