منابع مشابه
’Sorry’ is the hardest word
We are interested in the ways that language is used to achieve a variety of goals, where the same utterance may have vastly different consequences in different situations. This is closely related to the topic of creativity in language. The fact that the same utterance can be used to achieve a variety of goals opens up the possibility of using it to achieve new goals. The current paper concentra...
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We describe a detailed experimental investigation of the phase transition for several diierent classes of satissability problems including random k-SAT, the constant probability model, and encodings of k-colourability and the independent set problem. We show that the conventional picture of easy-hard-easy behaviour is inadequate. In each of the problem classes, although median problem diiculty ...
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Transition-metal (TM) nitrides are a class of compounds with a wide range of properties and applications. Hard superconducting nitrides are of particular interest for electronic applications under working conditions such as coating and high stress (e.g., electromechanical systems). However, most of the known TM nitrides crystallize in the rock-salt structure, a structure that is unfavorable to ...
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The Subset Sum problem asks whether a given set of n positive integers contains a subset of elements that sum up to a given target t. It is an outstanding open question whether the O∗(2n/2)-time algorithm for Subset Sum by Horowitz and Sahni [J. ACM 1974] can be beaten in the worst-case setting by a “truly faster”, O∗(2(0.5−δ)n)-time algorithm, with some constant δ > 0. Continuing an earlier wo...
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We prove that any decision procedure for a modest fragment of L. Henkin's theory of pure propositional types 7, 12, 15, 11] requires time exceeding a tower of 2's of height exponential in the length of input. Until now the highest known lower bounds for natural decidable theories were at most linearly high towers of 2's and since mid-seventies it was an open problem whether natural decidable th...
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ژورنال
عنوان ژورنال: American Journal of Orthodontics and Dentofacial Orthopedics
سال: 2021
ISSN: 0889-5406
DOI: 10.1016/j.ajodo.2020.12.004