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Sjoerd C. de Vries Astrid M. L. Kappers Jan J. Koenderink 《Attention, perception & psychophysics》1993,53(1):71-80
We used quadratic shapes in several psychophysical shape-from-stereo tasks. The shapes were elegantly represented in a 2-D parameter space by the scale-independentshape index and the scale-dependentcurvedness. Using random-dot stereograms to depict the surfaces, we found that the shape of hyperbolic surfaces is slightly more difficult to recognize than the shape of elliptic surfaces. We found that curvedness (and indirectly, scale) has little or no influence on shape recognition. 相似文献
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Information about the intent to emigrate was collected for a sample of 960 adolescents living in the northern region of Portugal. This question was part of a detailed questionnaire designed to assess specific issues concerning social representations of migration-namely, information, attitude, and fields of representation. Using information about the sociodemographic characteristics and the components of social representation mentioned above, our aim was to identify the independent predictors underlying the adolescent's intent to emigrate. Due to the great number of factors involved in the analysis, we conducted a preliminary selection of independent predictors within each of the aforementioned components and created a global index describing their importance. The findings indicate that, among all components of a social representation, attitude and representation of detachment and adaptation are the most important predictors of intent to emigrate. The relatively poor ability of sociodemographic variables to predict a future emigration does not mean that they are not important, but rather that they are more likely to condition attitude, the strongest predictor of a future emigration in the northern region of Portugal. The implication of these findings for handling intervening migration policies is discussed. 相似文献
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Job Satisfaction Among Ethnic Minorities in The Netherlands 总被引:1,自引:0,他引:1
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Escape and avoidance that are disproportional to the danger of the pertinent stimulus are important clinical problems that are often related to inaccurate (catastrophic) expectations. One possible source of such expectations is a prior, underestimated aversive experience. In the present experiment the hypotheses that underestimated pain leads to escape and that it leads to avoidance were tested. In order to control for the effect of the intensity of the pain stimulus, a control group that received 20 pain stimuli of high intensity was formed. Subjects in the experimental condition received 17 pain stimuli of low intensity and 3 of (unexpectedly) high intensity (experimentally induced underprediction). Underprediction of the high intensity stimulus was significantly related to escape, but not to avoidance. The results suggest that the way in which avoidance was operationalized accounts for this. The strong support of the hypothesized relationship between underpredicted pain and escape is an important finding, however. 相似文献
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Marcus Kracht 《Studia Logica》1990,49(4):455-470
Given a normal (multi-)modal logic a characterization is given of the finitely presentable algebras A whose logics L
A split the lattice of normal extensions of . This is a substantial generalization of Rautenberg [10] and [11] in which is assumed to be weakly transitive and A to be finite. We also obtain as a direct consequence a result by Blok [2] that for all cycle-free and finite A
L
A splits the lattice of normal extensions of K. Although we firmly believe it to be true, we have not been able to prove that if a logic splits the lattice of extensions of then is the logic of an algebra finitely presentable over ; in this respect our result remains partial. 相似文献
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This case study concerns an 18-year-old bilingual girl who suffered a radiation lesion in the left (dominant) thalamic and temporal region when she was 4 years old. Language and memory assessment revealed deficits in auditory short-term memory, auditory word comprehension, nonword repetition, syntactic processing, word fluency, and confrontation naming tasks. Both languages (English and Dutch) were found to be affected in a similar manner, despite the fact that one language (English) was acquired before and the other (Dutch) after the period of lesion onset. Most of the deficits appear to be related to verbal (short-term) memory dysfunction. Several hypotheses of subcortical involvement in memory processes are discussed with reference to existing theories in this area. 相似文献
39.
Transparent layer constancy 总被引:1,自引:0,他引:1
W Gerbino C I Stultiens J M Troost C M de Weert 《Journal of experimental psychology. Human perception and performance》1990,16(1):3-20
Perceived transparency was studied as a constancy problem. In the episcotister (E-) model of scission, luminances are partitioned into layer and background components; four luminances determine values of two layer parameters that specify constancy of a transparent layer on different backgrounds. The E-model was tested in an experiment in which 12 Ss matched 24 pairs of four-luminance patterns by adjusting two luminances of the comparison pattern. Both the standard and the comparison were perceived as a transparent layer on a checkerboard. The E-model predicts matches when layer values are identical in the two patterns. One parameter was constant, constraining the adjustment along the second dimension. Obtained values corresponded well with E-predictions. Alternative models based on local luminance or average contrast ratios accounted for less variability. Results indicate that transparency models should utilize luminance, not reflectance, as the independent variable. 相似文献
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