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991.
Most visual images contain “gross shapes” which are highly correlated with less perceptable “details,” e.g., the gross outline of a head and details such as eyes, ears, etc. The role of such structural redundancy in perception is considered both from a “syntactical” and “spatial-frequency” view of structure. An experiment is reported and evaluated in terms of a simple mathematical model which allows one to isolate the influence of several factors in the perceptual process, particularly the observer’s actual sensitivity to specific details and the influence of the redundant (correlated) information in “higher order forms,” The basic idea is that one decides whether a particular (target) detail is present in a briefly presented image by integrating impressions from various parts of the image in a weighted manner, with the weights determined by redundant information in “higher order forms.” Furthermore, the results are generally consistent with the notion that an increase in the number of attended letters does not reduce the information extracted from each letter.  相似文献   
992.
The use of complementary metal oxide semiconductor (CMOS) technology to produce fixed-ratio and random-ratio schedules is described. Such a technology implies several advantages over traditional methods of construction, especially with respect to cost and complexity. Suitable interfaces for linking with everyday laboratory equipment are also described.  相似文献   
993.
Within their domestic and marginal domains, women have power but no authority. Through their experiences in these domains, women acquire remarkable skills and ingenuity which partially enable them to quickly integrate new occupational skills demanded by the crisis of war. Women's partial socialization into masculine roles, their continual domination by male authority, and their preferred minority status further prepare women to appropriately exercise authority in concert with power in the context of war. The two related areas of women after war and women as warriors are briefly explored.In am particularly indebted to William Arkin for reading an earlier version of this paper and for his consistently clear and valuable insights. I would also like to thank Jacqueline St. John and Forrest Frank for some of the historical and military examples in the exploration of women as warriors.  相似文献   
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This study was conducted to investigate the effect of sexual stereotyping on the exercise of authority. The hypotheses were that the sexual composition of the group affects the authority behavior of group leaders when the task has low clarity but that sex characteristics have no effect on authority behavior when the task has high clarity. These predictions were expected to hold both in situations where there is a direct association between sex and the task ability and in situations where no such connection is established. As predicted, no significant difference was found in the number of high control acts made by male and female leaders in the high task clarity conditions, even when sex was directly related to the task ability. Also as hypothesized, sex effects did operate strongly in the low task clarity conditions. Male leaders made significantly more high control acts than female leaders, even in conditions where no prior relation was established between sex and the task ability. Thus, these results indicate that the effect of sex characteristics on the exercise of authority is enhanced in low task clarity situations and is neutralized in high task clarity situations.A preliminary version of this paaper was presented at the West Coast Conference for Small Group Research, San Francisco, California, April 24, 1974. We would like to acknowledge the comments made by Anne McMahon and Mary Walshok and the research assistance provided by Sue Aldrich, Patti Baird, Jim Hart, Debbie Jones, Glenn Kassel, Jane Morrison, Karen Scheblein, and Kay Smith.  相似文献   
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Two experiments on the PRP were performed in which the signal information was kept constant while varying the response information. The first experiment shows that delays are considerably increased by increasing response information. The second experiment re-affirms this result using unidimensional rather than multidimensional signals. The relevance of these results to theories of PRP is discussed.  相似文献   
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