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The effects of salience on 4- and 6-year-old children's ability to classify multiplicatively was investigated. A rank-ordered salience hierachy consisting of 3 dimensions was first assessed for each S. Several weeks later half the Ss of each age group were presented with a series of 9 3 times 3 matrix problems consisting of values from 2 dimensions ranked high in salience. The remaining half received identically structured matrices consisting of values from 1 highly salient dimension and of others from a dimension ranked low in salience. The goal in each problem was to select that compound stimulus from a set of alternatives that appropriately filled an empty cell in the matrix. Prior to the matrix problems, half the Ss in each matrix condition received sensitization training designed to increase the salience of the relevant dimensions in the matrix problems. The results showed that the pre-assessed salience of the relevant dimensions affected matrix solution in that more accurate performance was associated with those problems with both relevant dimensions relatively high in salience than those with one high and one low. Although the older Ss solved more problems, the evidence for coordination in the younger Ss was clear. No effects of sensitization training were found.  相似文献   
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A mathematical theory is developed for an imagined device termed a “junctor”. A junctor could be used to interconnect two n-terminal networks giving rise to another n-terminal network. Actually a junctor is itself a simple network with three banks of n-terminals internally connected in some fashion by perfectly conducting wires. Adjacency matrices are formulated to analyze various junctors and their current flows. The main problem treated concerns conditions which would ensure that the junctor operation is associative.  相似文献   
916.
The functional integral representation for the space-time Hopf characteristic functional associated with boundary-free incompressible fluid turbulence is evaluated accurately to order R-2, where R is the dimensionless Reynolds number in the theory. This work extends the results obtained previously for C-dominant turbulence to the regime of experimentally accessible large Reynolds numbers. We obtain a characteristic functional of non-Gaussian form as an asymptotically exact solution to the theory for large values of R. Two-point and three-point velocity correlation tensors of physical interest are derived from the characteristic functional.  相似文献   
917.
The principles of X-ray photoelectron spectroscopy are outlined. The application of this technique to the study of the electronic structure of metals, alloys and compounds is illustrated using data in Ag, β-brass, ReO3 and VO2. In the latter a major change in the density of states is observed on passing through the metal-insulator transition.  相似文献   
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