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51.
The paper studies the relation between systems of modal logic and systems of consequential implication, a non-material form of implication satisfying Aristotle's Thesis (p does not imply not p ) and Weak Boethius' Thesis (if p implies q, then p does not imply not q ). Definitions are given of consequential implication in terms of modal operators and of modal operators in terms of consequential implication. The modal equivalent of Strong Boethius' Thesis (that p implies q implies that p does not imply not q) is identified.  相似文献   
52.
Given a 1-ary sentence operator , we describe L - another 1-ary operator - as as a left inverse of in a given logic if in that logic every formula is provably equivalent to L. Similarly R is a right inverse of if is always provably equivalent to R. We investigate the behaviour of left and right inverses for taken as the operator of various normal modal logics, paying particular attention to the conditions under which these logics are conservatively extended by the addition of such inverses, as well as to the question of when, in such extensions, the inverses behave as normal modal operators in their own right.  相似文献   
53.
An alternating treatments design was used to compare the effects of active student response (ASR) and on-task (OT) instruction on the acquisition and maintenance of health facts during small-group lessons. Five students with learning difficulties (4 students identified as developmentally handicapped and 1 student identified as learning disabled) participated in daily instruction on weekly sets of 20 unknown health facts (10 facts assigned to the ASR condition and 10 to the OT condition). During ASR instruction, the teacher modeled the correct response to a health question that was presented visually on a health fact card, and the students immediately repeated the correct response in unison three times. During OT instruction, students attended visually to the health fact card as the teacher modeled the correct response. All 5 students made more correct responses on end-of-day tests on health facts taught with ASR instruction than they did on health facts taught with OT instruction. ASR instruction also produced consistently superior results on maintenance tests administered 2 weeks after instruction.  相似文献   
54.
We examined the effect of self-correction on the acquisition, maintenance, and generalization of written spelling of elementary school students attending an after-school clinic. Six students registered for remedial tutoring participated. During self-correction, students initially learned four proofreading marks and a procedure for using them that were subsequently applied as the students compared their spelling to a model. Results showed a functional effect between self-correction and improved student performance on target words. Using the self-correction procedure, the students spelled at least 98% of the target words accurately, maintained at least 85% of the correctly spelled words, and generalized at least 70% of the words at home, in context, and with word variations. Questionnaires administered to the students, their parents, and teachers indicated that students preferred self-correction. Parents noticed academic improvements in their child's spelling performance as well as positive changes in attitude toward school. Most teachers did not notice changes in spelling performance or attitude.  相似文献   
55.
56.
How can we explain that an assertion on something perceived can be understood in the same manner by somebody who cannot perceive that scene? This problem bases the interest in computational linguistics in how listener modeling could possibly be harmonized with reference semantics. Mental images substituting real perception appear as a way out. The architecture of the listener model has to be adapted to the creation and use of such pictorial data structures. Furthermore, the relation between the latter and a verbal (i. e., propositional) representation must be understood. The resulting architecture of a listener model with reference semantics can be employed to solve communicational problems from three general classes in a better way, as is demonstrated by an example implementation.  相似文献   
57.
The present study investigated the role of the work value of fairness and attributions regarding the causes of absence in supervisor disciplinary decisions. It was hypothesized that supervisors who valued fairness, and those who made internal attributions regarding the cause of a particular absence incident, render more severe disciplinary decisions than supervisors who value fairness less, and who make external attributions. Furthermore, it was hypothesized that the degree to which supervisors valued fairness moderates the relationship between external attributions and the severity of disciplinary decisions. Using a policy capturing approach, results were consistent with predictions. Implications of the results for research and practice are discussed.  相似文献   
58.
In the present study, a naturalistic functional analysis procedure was used to assess the effect of environmental stimulation on the stereotypic behavior (body rocking) of an adult whose stereotypy appeared to be induced by an acquired brain injury. Environmental stimulation, operationalized in terms of both physical and social characteristics, resulted in only minimal changes in the occurrence of body rocking. Body rocking occurred in excess of 50% of the observations in all environmental stimulation conditions and in a naturally occurring baseline condition. To our knowledge, this is the first published report of a functional analysis of stereotypy associated with acquired brain injury.  相似文献   
59.
As part of this special issue on psychology in primary care settings, we describe the Department of Veterans Affairs' (VA's) new approach to education for practice in the primary care setting and we concurrently address some general issues related to the education of clinical psychologists for practice in this setting. In this article we argue that the primary care psychologist, in parallel with the generalist in medicine, must have a strong generic background in clinical psychology in order to gain the broad range of clinical skills necessary to function effectively as an in-depth generalist (IDG) who is capable of addressing the variety of psychological issues that emerge in the primary care setting. The IDG model of professional practice, which we believe is best suited for primary care/managed care settings, requires extensive training in generic clinical skills and increased time devoted to its implementation at both the predoctoral and the postdoctoral levels.  相似文献   
60.
Aggressivity, inattention, hyperactivity, and impulsivity are cardinal dimensions of externalizing behavior problems of childhood. They are diagnostic and clinical features of childhood disorders, and are thought to be linked to the subsequent development of adult disorders such as substance abuse (SA). Little is known, however, about the convergent and discriminant validity of these four constructs. We used multiple measures to develop indices of aggressivity, inattention, hyperactivity, and impulsivity in a sample of 10- to 12-year-old boys (N=183) with and without a family history of SA. Data were taken from mother reports, child reports, teacher reports, and laboratory tasks. The study aims were (1) to test the convergent and discriminant validity of aggressivity, inattention, hyperactivity, and impulsivity; (2) to examine whether the data were consistent with a model specifying the four constructs as indicators of one superordinate factor; and (3) to differentiate boys with and without a family history of SA in construct scores. The results supported the convergent and discriminant validity of the four constructs. Although discriminable, the constructs covaried strongly and were consistent with a model specifying them as indicators of a single superordinate factor. Boys with a family history of substance abuse scored higher than control boys on aggressivity, inattention, and impulsivity scores, but the groups did not differ on hyperactivity scores. The results are discussed in terms of the role of childhood behavior problems in vulnerability to SA.This work was supported by the National Institute on Drug Abuse grant No. DA 05605.  相似文献   
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