On Restarting Automata with Rewriting
نویسندگان
چکیده
Motivated by natural language analysis we introduce restarting automata with rewriting. They are acceptors on the one hand, and (special) regulated rewriting systems on the other hand. The computation of a restarting automaton proceeds in cycles: in each cycle, a bounded substring of the input word is rewritten by a shorter string, and the computation restarts on the arising shorter word. We show a taxonomy of (sub)variants of these automata taking into account (non)determinism and two other natural properties. Theoretical signiicance of the restarting automata is also demonstrated by relating it to context-free languages (CFL), by which a characterization of deterministic CFL is obtained.
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