David K. Hofer

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We have recently proposed augmenting clauses in a Boolean database with groups of permutations, the augmented clauses then standing for the set of all clauses constructed by acting on the original clause with a permutation in the group. This approach has many attractive theoretical properties, including representational generality and reductions from(More)
This is the third of three papers describing zap, a satisfiability engine that substantially generalizes existing tools while retaining the performance characteristics of modern highperformance solvers. The fundamental idea underlying zap is that many problems passed to such engines contain rich internal structure that is obscured by the Boolean(More)
Two experiments demonstrate the influence of an unconscious form of information storage on behavior. In the learning phase, subjects see pictures in which other pictures or figures are embedded. The experimental procedure makes sure that these embedded figures cannot be seen (or consciously identified) by the subjects. Nevertheless, the results of a(More)
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