A string Turing machine is a variant of a Turing machine designed for easy manipulation of strings. In contrast to the standard Turing machine, a string Turing machine can insert and delete squares on the tape. It is easy to see that the models of standard and string Turing machines are equivalent in computing power. However, in case of the string Turing machine, imposing certain restrictions o...

" In this paper, we define a fuzzy imperative programming language (called L), powerful enough to express crisp and fuzzy algorithms. Its small instruction set is designed to enhance readability, and it is proved before that the class of functions that can be programmed in L is equivalent to the class of functions computed by a W-Turing machine and to the W-recursive functions. The language is ...

Tile-based self-assembly is a model of “algorithmic crystal growth” in which square “tiles” represent molecules that bind to each other via specific and variable-strength bonds on their four sides, driven by random mixing in solution but constrained by the local binding rules of the tile bonds. In the late 1990s, Erik Winfree introduced a discrete mathematical model of DNA tile assembly called ...

In this article we shall review several basic de-nitions and results regarding quantum computation. In particular, after de-ning Quantum Turing Machines and networks the paper contains an exposition on continued fractions and on errors in quantum networks. The topic of simulation of Quantum Turing Machines by means of obvious computation is introduced. We give a full discussion of the simulatio...

In recent years, much research has been devoted to the synthesis of gigabit switches; on the other hand, few have explored the refinement of hash tables. In fact, few cryptographers would disagree with the improvement of the lookaside buffer. In this work, we use signed technology to show that architecture and superblocks are usually incompatible.

This paper first proves the Savitch Theorem: any nondeterminstic L(n)− tape bounded Turing Machine can be simulated by a deterministic [L(n)]− tape bounded Turing machine, provided L(n) ≥ log2n. Then as an attempt to answer the following question: “Given a nondeterministic tape bounded Turing machine which accepts set A, how much additional storage does a deterministic Turing machine require to...

We present a small time-efficient universal Turing machine with 5 states and 6 symbols. This Turing machine simulates our new variant of tag system. It is the smallest known universal Turing machine that simulates Turing machine computations in polynomial time.

Turing machine space complexity is related to circuit depth complexity. The relationship complements the known connection between Turing machine time and circuit size, thus enabling us to expose the related nature of some important open problems concerning Turing machine and circuit complexity. We are also able to show some connection between Turing machine complexity and arithmetic complexity.

The Turing Machine has two implicit properties that depend on its underlying notion of computing: the format is fully determinate and computations are information preserving. Distributed representations lack these properties and cannot be fully captured by Turing’s standard model. To address this limitation a distributed extension of the Turing Machine is introduced in this paper. In the extend...

Abstract Geometrical Computation as a new model of computation is the counterpart of Cellular Automata that has Turing computing ability. In this paper we provide an algorithm to simulate Alternating Turing Machine in the context of Signal Machine using techniques adopted from the features of Signal Machine to set up and manage the copies/branches of Alternating Turing Machine. We show that our...