منابع مشابه
To grow or to shrink…
Aurora B puts chromosomes in their place mall molecule inhibitors of Aurora B activity, characterized by Hauf et al. (page 281) and Ditchfield et al. (page 267), reveal that the mammalian kinase and its budding yeast counterpart, Ipl1, have similar functions. Without Aurora B, mistakes in kinetochore–chromosome interactions go uncorrected. Early evidence of a function for the Aurora family in c...
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Learning when limited to modiication of some parameters has a limited scope; the capability to modify the system structure is also needed to get a wider range of the learnable. In the case of artiicial neural networks, learning by iterative adjustment of synaptic weights can only succeed if the network designer predeenes an appropriate network structure, i.e., number of hidden layers, units, an...
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Markov networks are models for compactly representing complex probability distributions. They are composed by a structure and a set of numerical weights. The structure qualitatively describes independences in the distribution, which can be exploited to factorize the distribution into a set of compact functions. A key application for learning structures from data is to automatically discover kno...
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We study the solutions of Von Neumann's expanding model with reversible processes for an infinite reaction network. We show that, contrary to the irreversible case, the solution space need not be convex in contracting phases (i.e. phases where the concentrations of reagents necessarily decrease over time). At optimality, this implies that, while multiple dynamical paths of global contraction ex...
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ژورنال
عنوان ژورنال: Nature
سال: 1993
ISSN: 0028-0836,1476-4687
DOI: 10.1038/362201a0