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131.
High-resolution CRT displays are subject togeometric distortion: lines that are straight in the internal coordinates of the graphics software and hardware are curved when projected onto a plane in the observer’s line of sight. As the available resolution of CRT screens increases, it becomes more difficult to measure and correct for this distortion. We present a simple, highly accurate method for determining the mapping between internal coordinates and the viewing plane. It requires that an observer, using a calibration program, adjust triples of displayed points until they are collinear. A metal straightedge placed between the observer and the screen aids in this judgment. We describe the calibration of an IBM Enhanced Graphics Display in high-resolution mode (350 × 640 pixels), and illustrate how to use the estimated mapping to choose internal coordinates to draw undistorted figures that are accurate to within 0.5 pixel. The method can be used to assess or to correct the accuracy of visual displays. The method is relevant to experiments in spatial vision, spatial perception, perception of dot patterns, and any application in which geometrically accurate stimuli are required.  相似文献   
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An emergent social science of knowledge applications, drawing on a substantial multidisciplinary literature published over the past twenty-five years, signals an inversion of typical scholarly reasoning about the knowledge-society nexus. Whereas most scholarly research thus far has concentrated on conditions believed to affect the production of scientific and professional knowledge, we pose a new problematic: What must we examine in order to comprehend and consciously shape applications of scientific and professional knowledge to the manifold problems facing contemporary societies? To date, approaches to this problematic have proceeded on the basis of four broadly accepted if abstract theses about the nature of contemporary knowledge systems: subjectivity, corrigibility, sociality, and complexity. Within the boundaries supplied by these commonly accepted theses are unresolved controversies expressed in competing visions of complexity, alternative perspectives of causation, rival images of progress, and conflicting criteria of application.  相似文献   
135.
Burden of proof     
This paper presents an analysis of the concept of burden of proof in argument. Relationship of burden of proof to three traditional informal fallacies is considered: (i) argumentum ad hominem, (ii) petitio principii, and (iii) argumentum ad ignorantiam. Other topics discussed include persuasive dialoque, pragmatic reasoning, legal burden of proof, plausible reasoning in regulated disputes, rules of dialogue, and the value of reasoned dialogue.  相似文献   
136.
This paper describes an amplifier for an electroencephalograph with gain of 1×104 to 1×106 and made entirely of commercially available IC components. The two-stage amplifier has a preamplifier stage with fixed gain of 1000, and a second stage with variable gain from 1 to 100. The final stage, an anti-aliasing filter, adds a gain of 10 to the signal. The circuit has high common mode rejection, low input bias current, very low noise characteristics, low offset voltages, and offset nulling capability built into the circuit.  相似文献   
137.
Maternal handling and motor development: an intracultural study   总被引:1,自引:0,他引:1  
Citing a distinction between informal and formal routines used by mothers in handling their infants, we examined formal handling routines, in which the caregiver acts in a pedagogical manner; these routines are widespread in many non-Western countries. We hypothesised that formal handling serves to facilitate gross motor development during early infancy. To examine this hypothesis, the effects of a Jamaican formal handling routine on a broad range of developmental outcomes was examined. Results showed that the effects were specific to early gross motor development and in particular to postural control along the vertical axis of the body. Information is also provided on other aspects of Jamaican child care. It seems that the handling routine forms part of a folk (developmental) medicine system and may serve not only to promote child health but also as a sort of developmental neurological examination.  相似文献   
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Neutrality is a central concept within the theory of psychoanalytic technique. We spell out the major controversies in which the concept has become embroiled, and provide a definition that we believe coincides with actual psychoanalytic practice. We discuss its merits and weaknesses, noting also the negative consequences of relying on older definitions. We relate neutrality to the interpretive process, indicating ways interpretation protects neutrality and is made more effective by it. We discuss the complex and controversial relation between neutrality and the analyst's therapeutic intent.  相似文献   
140.
To study malevolent representations, earliest memories were reliably coded on scales of affect tone. Ss were diagnosed with borderline personality disorder: 31 without and 30 with concurrent major depression. Nonborderline comparison subjects had either major depressive disorder (n = 26) or no psychiatric diagnosis (n = 30). Borderline subjects were discriminated from comparison subjects by their more malevolent representations; they more frequently produced memories involving deliberate injury; and they portrayed potential helpers as less helpful. Results suggest the diagnostic significance of malevolent representations, which need to be explained by any theory of borderline personality disorder.  相似文献   
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