1,947 research outputs found
On implicit-factorization constraint preconditioners
Recently Dollar and Wathen [14] proposed a class of incomplete factorizations for saddle-point problems, based upon earlier work by Schilders [40]. In this paper, we generalize this class of preconditioners, and examine the spectral implications of our approach. Numerical tests indicate the efficacy of our preconditioners
On reliable computation by noisy random Boolean formulas
We study noisy computation in randomly generated k-ary Boolean formulas. We
establish bounds on the noise level above which the results of computation by
random formulas are not reliable. This bound is saturated by formulas
constructed from a single majority-like gates. We show that these gates can be
used to compute any Boolean function reliably below the noise bound.Comment: A new version with improved presentation accepted for publication in
IEEE TRANSACTIONS ON INFORMATION THEOR
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