Observation of String-Rewriting Systems

In most models of computation, a device performs some type of process, and only some final output is regarded as the result. In adding an observer to such a device, one can obtain a protocol of the entire process and then use this as the computation's result. In a series of articles this approach has proved to often exceed greatly the power of the system observed. Here we apply this architecture to string-rewriting systems. They receive a string as input, and a combination of observer and decider then determines whether this string is accepted. This decision is based only on the rewriting process performed. First we determine the powers of painter, contextfree, and inverse context-free rewriting systems in terms of McNaughton languages. Then these are investigated as components of rewriting/observer systems, and we obtain characterizations of the context-sensitive and the recursively enumerable languages. Finally we investigate some limitations, i.e. characterize some systems, whe...

• Type: Journal
• Year: 2006
• Where: FUIN
• Authors: Matteo Cavaliere, Peter Leupold
• Keywords: Entire Process, Final Output, FUIN 2006, String-rewriting Systems