Uniform circuits and exclusive read PRAMs

  • Inga Niepel
  • Peter Rossmanith
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 560)


CRCW-PRAMs were characterized in terms of unbounded fan-in circuits. The idea of unambiguous circuits lead to a characterization of CREW-PRAMs. In this paper circuits are considered which consist of OR and NOT gates and additionally of gates that compute the cartesian product. These circuits are equivalent to traditional circuits composed of OR, AND, and NOT gates. However, if fan-out is bounded this is no longer true. If this concept is combined with the concept of unambiguity of circuits, the resulting circuits exactly characterize EREW-PRAMs. This solves an open question posed by Stockmeyer and Vishkin [22]. Furthermore, all other memory access restrictions of PRAMs are shown to have a characterization in terms of circuits with gates of type OR, NOT, and cartesian product.


Memory Cell Global Memory Program Line Random Access Machine Parallel Random Access Machine 
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 1991

Authors and Affiliations

  • Inga Niepel
    • 1
  • Peter Rossmanith
    • 1
  1. 1.Institut für InformatikTechnische Universität MünchenMünchen 2

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