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151.
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In 11 male albino rats, lever-pressing responses, maintained under a CRF escape schedule with light as the aversive stimulus, were examined at each of five intensities, viz., 2.5, 18, 105, 190, and 386 ft-C. The function relating reciprocal of latency of the escape response to aversive light intensity passed through a maximum.  相似文献   
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Graphic designers and an experimental psychologist worked together to improve the design of two map symbols which are frequently confused: the symbols for cuttings and embankments on topographic maps. The problem was analysed in terms of the function of the symbols and their likely cognitive representations. Tests were developed to evaluate alternative designs, including an intervisibility task which requirred users to visualize the landform from the symbols viewed in the context of a map. Tests were given to schoolchildren and to experienced map users in order to compare the standard symbols with five alternative designs. Children's performance was strongly affected by the symbols they used, but experienced users were much less affected. After some refinement of the symbols a further experiment demonstrated the superiority of a number of alternative designs over the existing symbols on a range of test: scores were almost double on the intervisibility task. The paper makes recommendations to cartographers and argues for greater consideration of the inexperienced map user in the design process.  相似文献   
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A new approach is described for the development and structure of perceptual knowledge-based systems. This systematic method for acquiring perceptual knowledge for use in knowledge-based systems and for representing perceptual knowledge within the systems has revealed that two broad classes of perceptual activity can each be characterized by a single logical operator. The number of rules necessary to accomplish particular perceptual tasks can also be estimated.  相似文献   
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The present paper is a commentary on an article by Drew Leder [1]. Leder identifies a series of texts in the clinical encounter, emphasizes the central role of interpretation in making sense of each of these texts, and articulates ordering principles to guide the interpretive work.The metaphor of clinical work as textual explication, however, creates the expectation that there is a text somewhere to be found. Such an expectation invites doctors and patients to search for the text and runs the risk of conceptualizing patients as more static than they are. If one is to use the textual metaphor, one must appreciate the radical extent to which the clinical encounter is a mutually produced and shifting entity. The qualities of mutuality and indeterminacy are not those one usually associates with texts. One might ultimately be better served by a different metaphor based more directly on uncertainty.  相似文献   
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