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51.
A running-wheel-movement-detection system is described for use with an IBM-compatible system and a serial mouse. It is an adaptation of a system developed for use on a Commodore 64. The IBM-compatible system provides obvious advantages in speed, memory, data storage, and programming ease over the earlier Commodore 64 system.  相似文献   
52.
Conclusion I have shown (to my satisfaction) that Leibniz's final attempt at a generalized syllogistico-propositional calculus in the Generales Inquisitiones was pretty successful. The calculus includes the truth-table semantics for the propositional calculus. It contains an unorthodox view of conjunction. It offers a plethora of very important logical principles. These deserve to be called a set of fundamentals of logical form. Aside from some imprecisions and redundancies the system is a good systematization of propositional logic, its semantics, and a correct account of general syllogistics. For 1686 it was quite an accomplishment. It is a pity that Leibniz himself did not fully appreciate what he had achieved. It does seem to me that this was due in part, as the Kneales urge (Note 4), to his having kept the focus of his attention on traditional syllogistics. It is a great pity that he did not polish GI 195–200 for publication. The publication of GI 195, 198, and 200 would have most likely promoted further research.This paper was conceived in a Seminar on the Generales Inquisitiones offered by Professor Klaus Jacobi at the University of Freiburg during the 1987 winter semester. I am grateful to him for having allowed me to participate in that exciting seminar. I am grateful to all the seminar participants, especially to Professor Jacobi, Professor Klaus Erich Kaehler, Doctor Helmut Pape, and Herr Hans-Peter Engelhart for sustained and illuminating discussions of some passages of the GI. Jacobi was extremely kind in reading the second version of this paper with a highly refined comb. I am most grateful to him for having pointed out typos, stylistic infelicities, and conceptual obscurities. He also provided advice on the translation, and, most generously and cooperatively, offered suggestions for improving the exposition and the arguments.  相似文献   
53.
Mental models constitute an alternative to the rule-based systems in the explanation of human reasoning (Johnson-Laird, 1983). In this paper, we claim that the concept of believability generally used to categorize content and context effects is of little use within a semantic theory. Thus, we propose the use of categories that are directly extracted from subjective relations among concepts within the reasoning problem. We demonstrate that manipulations based on this kind of categorization produce predictable patterns of responses in reasoning problems. We present two experiments to test our predictions, using conditional and syllogistic reasoning problems, and in both cases, we demonstrate the influence of conceptual knowledge not only in natural contexts, but also in experimentally created artificial contexts.  相似文献   
54.
We studied the course of aggressive behavior in an epidemiologically defined sample of first graders with and without comorbid anxious symptoms. Our primary purpose in doing so was to understand whether the stability of aggression in young children was attenuated or strengthened in the presence of comorbid anxiety. Previous studies of older children and adolescents had produced equivocal findings in this regard. Data on anxious symptoms were obtained through an interview of the children, whereas aggressive behavior was assessed through the use of a teacher interview and peer nominations. Assessments were performed in the fall and spring of first grade. In contrast to children classified as aggressive alone in the fall of first grade, boys and girls classified as aggressive and anxious in the fall of first grade were significantly more likely to be classified as aggressive in the spring in terms of teacher ratings and/or peer nominations of aggression. Thus our findings suggest that the link between early and later aggression may be strengthened in the presence of comorbid anxious symptoms, rather than attenuated. Future studies are needed to identify the mechanisms by which the course of aggression is influenced by the presence of comorbid anxiety.The writing of this paper was supported by the following National Institute of Mental Health grants: Epidemiologic Prevention Center for Early Risk Behavior (P50 MH38725); Periodic Outcome of Two Preventive Trials (1RO1 MH42968). The authors would like to thank the Baltimore Public City School System and the children and parents who participated in this study.  相似文献   
55.
Forty-six reading disabled adolescents were randomly assigned to one of three 25-hr instructional programs. Two programs provided training in expository text comprehension, and a third offered training in academic problem solving and organizational and study skills (an alternative treatment control). One reading comprehension program was designed to remediate a deficient knowledge base, forcing disabled readers to elaborate and further process new text knowledge, focusing on both specific informational content in a text and knowledge of text structure per se. The second program was patterned after the Palincsar and Brown (1984) reciprocal teaching techniques and focused on training four text comprehension strategies used by skilled comprehenders. Both the “knowledge-base” and the “strategy” training approaches were associated with significant improvement in disabled readers' comprehension skills, although training effects did not generalize across all aspects of reading comprehension performance. Strategy-trained readers applied the trained strategies with equal success on instructed and uninstructed text materials, providing strong evidence of transfer of learning. Knowledge-base readers also demonstrated successful transfer of specifically trained procedures (semantic mapping, text analysis) to unfamiliar text. In both programs, the best outcomes were obtained when specific strategies and operations were targeted for training.  相似文献   
56.
A 15-year-old-boy was referred on account of a fluency disorder that was not thought to be stuttering. The problems of the lack of an adequate definition of cluttering are discussed along with the inherent problems of providing a wide-based assessment of this client group. Assessments were conducted on the motoric, linguistic, and intellectual abilities of this client, and the findings are discussed.  相似文献   
57.
This study tested predictions concerning the associations between children's nonparental care experiences and emotion regulation. It involved 53 participants (21 girls and 32 boys) of preschool age and their mothers. The children's care experiences ranged from those who were raised exclusively at home to those who had nonparental care experience beginning in early infancy. The participants were observed in a laboratory playroom, and their mothers were asked to complete questionnaires regarding their children's care histories and their current care situations. The children with extensive nonparental care backgrounds were found to be more likely to use self-directed emotion regulation behaviors when faced with a mildly frustrating situation. In the same situation, the children who had experienced minimal nonparental care were found to be more likely to use other-directed emotion regulation behaviors. Additionally, the children who had experienced care settings with large numbers of children in each care group or who had experienced many caregiver changes were more likely to use self-directed emotion regulation behaviors, whereas those who had experienced settings with smaller care groups and fewer caregiver changes were more likely to use other-directed emotion regulation behaviors.  相似文献   
58.
59.
In two experiments, the pattern of persistence of negative priming effects across delay intervals of 500 and 2,500 msec was assessed using a within-subjects, random sequencing of delays. Neill and Valdes (1992; Neill, Valdes, Terry, & Gorfein, 1992) have argued that a within-subject experimental design is required for decay of negative priming to be seen, in contrast to results reported elsewhere (e.g., Tipper, Weaver, Cameron, Brehaut, & Bastedo, 1991) showing stable negative priming effects across delays. In neither experiment was substantial evidence of decay detected, raising questions for the notion that suppression necessarily declines across brief temporal intervals and for the assertion that episodic retrieval is the sole source of negative priming.  相似文献   
60.
The sex of the main character was varied in six children's stories which were then read by fourth, sixth and eighth graders. The children answered four questions about the stories. Both boys and girls responded more positively to the questions “Would you like to be (character's name?)” and “Would you like to do the things (character's name) did?” when the main character was a male. Boys preferred stories about males, and this preference increased with grade level. A preference for stories about females was marginally significant only for the older girls. Theoretical and practical implications are discussed.  相似文献   
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