Weak parallel machines: A new class of physically feasible parallel machine models

  • Juraj Wiedermann
Invited Lectures
Part of the Lecture Notes in Computer Science book series (LNCS, volume 629)


Weak parallel machines represent a new class of physically feasible parallel machine models whose prominent representative is the so-called Parallel Turing Machine (PTM) as introduced by the author in 1984. Except PTMs, further members of this class are e.g. various kinds of systolic machines, cellular automata, orthogonal iterative arrays, etc. From the computational point of view the main common feature of weak parallel machines is their ability to perform pipelined computations efficiently, what is used in characterizing the corresponding machine class by so—called Pipelined Computation Thesis. This thesis states that on these machines the period of computation is polynomially related to the space of sequential Turing machine computations.

The paper gives a brief overview of the most important known results concerning PTMs and extends them by new results stressing the significance of PTMs in the context of physically feasible parallel computations.


Cellular Automaton Space Complexity Turing Machine Input Word Input Tape 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1992

Authors and Affiliations

  • Juraj Wiedermann
    • 1
  1. 1.INFOSTAT-Institute of Informatics and StatisticsBratislavaCzechoslovakia

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