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41.
In [2] a semantics for implication is offered that makes use of stories — sets of sentences assembled under various constraints. Sentences are evaluated at an actual world and in each member of a set of stories. A sentence B is true in a story s just when B s. A implies B iff for all stories and the actual world, whenever A is true, B is true. In this article the first-order language of [2] is extended by the addition of the operator the story ... says that ..., as in The story Flashman among the Redskins says that Flashman met Sitting Bull. The resulting language is shown to be sound and complete.  相似文献   
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Most of the empirical literature on juvenile homicide has emerged from the clinical experience of mental health professionals who have diagnosed and/or treated youngsters who killed. After a critical review of this literature, data on 787 juvenile homicide offenders are presented and discussed. These data indicate that intrafamilial killings represent but a small fraction of all homicides perpetrated by juveniles and that there are clear differences between intrafamilial and extrafamilial juvenile homicides.  相似文献   
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Children from 4 to 10 years old were presented with a serial recall task with pictures of common objects which had acoustically similar or dissimilar names, or with the spoken names of the pictures. Children of all ages showed consistently better recall of the pictures with dissimilar names. It is concluded, in contrast to some earlier studies, that children as young as 4 years are able to utilize a speech code as a means of memorizing pictures. With auditory presentation as in previous studies acoustic similarity had progressively more effect on recall with increasing age. The implications of these finding for current theories of short-term memory and its development are discussed.  相似文献   
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This paper provides a comprehensive formulation of Erik Erikson's theory of ego identity formation as it pertains to both the identity stage and to the remainder of the life cycle. The structure of the identity stage is discussed in terms of its more universal features and in terms of features more specific to North American society. The role played by “institutionalized moratoria” in influencing the outcome of the identity crisis and subsequent development is discussed in the context of two Eriksonian notions ignored in the literature: the value orientation stages and the struggle between the ego and superego for dominance of the personality. As part of the discussion, several constructive criticisms of Erikson's work are offered with the intent of making the theoretical formulation presented in this paper an appropriate basis for subsequent empirical investigations of his theory. One of the important implications of this paper is that it suggests that questions should be raised regarding the validity of the dominant research strategy currently in use.  相似文献   
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A design for an Apple II interface that senses relative rotary position and/or motion via a digital potentiometer is presented. A thorough discussion of the circuit’s theory of operation and a fully commented BASIC software listing are included. Suggested applications include an infinite-turn rotary device for psychophysical methods of adjustment, the sensing of rotary translations of a steering wheel in a driving simulator, and a digital tachometer/odometer for tracking performance on stationary exercise bicycles and treadmills.  相似文献   
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Two studies were conducted to investigate the effects of perceived control in two men's prisons, one housing 181 inmates and the other housing 623 inmates. In both prisons, inmates' perceived control over the environment was found to be significantly related to their ratings of their living accommodations, experienced stress, and physical symptoms, even when type of cell was held constant.  相似文献   
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