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51.
Bill Jones 《Attention, perception & psychophysics》1972,11(1):95-96
Following prolonged exposure to two vertical grating patterns differing in spatial frequency—one pattern illuminated in green light alternated with the other pattern illuminated in red light—human observers will sometimes report seeing desaturated complementary colors when presented with a neutrally illuminated test field consisting of adjacent halves of the two adapting gratings. The number of such color reports increases as the difference between the spatial frequencies of the adapting gratings increases. This frequency-specific chromatic aftereffect is similar to that obtained with orientation-specific color adaptation and may be mediated by neural “channels,” sensitive to both color and frequency input, which are similar to units known to exist in the visual systems of lower organisms. 相似文献
52.
The plastic barrel suit provides complete protection of chronically implanted fistulas and electrical connectors. The lost time, expense, and the frustrations of having these devices damaged was avoided. 相似文献
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Past studies have shown that stuttering is eliminated when speech is synchronized with a metronomic beat, but the speech sounds artificial. The present study investigated the effect of increasing the duration of these individual stimulus beats with the stimulus-off period constant at 1 sec. When subjects were instructed to speak during the stimulus-on period, stuttering was an inverse function of stimulus duration, indicating that the known metronome effect on stuttering is one point on a continuum of effective rhythm procedures. The "naturalness" of speech increased as the stimulus duration increased up to durations of about 2 sec, and then decreased. At optimal values, stuttering was greatly reduced and naturalness and rapidity of speech were retained. These optimal values effectively controlled stuttering in a field test that used two types of specially designed portable instruments, one of which produced a tactual stimulus and the other an auditory stimulus. 相似文献
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Lenore W. Harmon 《Journal of counseling and development : JCD》1967,45(9):895-900
The data used in this study were made available through the Center for Interest Measurement Research and the Student Counseling Bureau, University of Minnesota. Computer analysis was provided by the Numerical Analysis Center, University of Minnesota. While attempting to increase the number of A and B+ scores on the women's SVIB by varying the composition of the criterion group on marital status, it was found that the desired effect was achieved by using a different item selection and weighting system from Strong's original one and not by varying the marital status of the criterion group. The experimental scoring keys developed in the study also acted selectively on original scores of B and B—, raising or lowering them, and generally reducing their number. These findings went beyond the original hypotheses and intent of the study and suggested an explanation for the apparent heterogeneity of women's interests and the resulting difficulty in measuring them. 相似文献
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Factor analysis by minimizing residuals (minres) 总被引:1,自引:0,他引:1
This paper is addressed to the classical problem of estimating factor loadings under the condition that the sum of squares of off-diagonal residuals be minimized. Communalities consistent with this criterion are produced as a by-product. The experimental work included several alternative algorithms before a highly efficient method was developed. The final procedure is illustrated with a numerical example. Some relationships of minres to principal-factor analysis and maximum-likelihood factor estimates are discussed, and several unresolved problems are pointed out.The authors wish to thank the Factor Analysis Work Group (supported, in part, by ONR) for valuable criticisms and suggestions made in the course of a discussion of the present work in April, 1965. 相似文献
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