Multi-stranded String Assembling Systems

Abstract

Classical string assembling systems form computational models that generate strings from copies out of a finite set of assembly units. The underlying mechanism is based on piecewise assembly of a double-stranded sequence of symbols, where the upper and lower strand have to match. The generative power of such systems is driven by the power of the matching of the two strands. Here we generalize this approach to multi-stranded systems. The generative capacities and the relative power are our main interest. In particular, we consider briefly one-stranded systems and obtain that they describe a subregular language family. Then we explore the relations with one-way multi-head finite automata and show an infinite, dense, and strict strand hierarchy. Moreover, we consider the relations with the linguistic language families of the Chomsky Hierarchy and consider the unary variants of k-stranded string assembling systems.