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This paper is an attempt to give a general explanation of pragmatic aspects of linguistic negation. After a brief survey of classical accounts of negation within pragmatic theories (as speech act theory, argumentation theory and polyphonic theory), the main pragmatic uses of negation (illocutionary negation, external negation, lowering and majoring negation) are discussed within relevance theory. The question of the relevance of negative utterance is raised, and a general inferential schema (based on the so-called invited inference) is proposed and tested for the main uses of negation discussed in the paper.Translated from French by Anne Reboul and Lyne DaSylva.  相似文献   
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When an observer views a moving scene binocularly, both motion parallax and binocular disparity provide depth information. In Experiments lA-1C, we measured sensitivity to surface curvature when these depth cues were available either individually or simultaneously. When the depth cues yielded comparable sensitivity to surface curvature, we found that curvature detection was easier with the cues present simultaneously, rather than individually. For 2 of the 6 subjects, this effect was stronger when the component of frontal translation of the surface was vertical, rather than horizontal. No such anisotropy was found for the 4 other subjects. If a moving object is observed binocularly, the patterns of optic flow are different on the left and right retinae. We have suggested elsewhere (Cornilleau-Pérès & Droulez, in press) that this motion disparity might be used as avisual cue for the perception of a 3-D structure. Our model consisted in deriving binocular disparity from the left and right distributions of vertical velocities, rather than from luminous intensities, as has been done in classical studies on stereoscopic vision. The model led to some predictions concerning the detection of surface curvature from motion disparity in the presence or absence of intensity-based disparity (classically termedbinocular disparity). In a second set of experiments, we attempted to test these predictions, and we failed to validate our theoretical scheme from a physiological point of view.  相似文献   
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A general solution for weighted orthonormal Procrustes problem is offered in terms of the least squares criterion. For the two-demensional case. this solution always gives the global minimum; for the general case, an algorithm is proposed that must converge, although not necessarily to the global minimum. In general, the algorithm yields a solution for the problem of how to fit one matrix to another under the condition that the dimensions of the latter matrix first are allowed to be transformed orthonormally and then weighted differentially, which is the task encountered in fitting analogues of the IDIOSCAL and INDSCAL models to a set of configurations.The authors are grateful to the Editor and the anonymous reviewers for their helpful comments on an earlier draft of this paper.  相似文献   
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The essay examines the argument advanced by E.D. Hirsch, Jr., for instituting ‘cultural literacy’ as a fundamental priority of schools. A number of confusions and equivocations in Hirsch's reasoning are identified, and the propensity of his project to indoctrinate is exposed. Among the features of Hirsch's argument shown to be troubling are his shifting construal of ‘language’, his inconsistency about the requirements of cultural literacy, and his uncritical relation to traditional images of the American past and present. The upshot is to raise the question why Hirsch's project has elicited wide support and praise.  相似文献   
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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   
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Fourier analysis describes the amount of variation in a time series by partitioning it into sinusoids of different amplitudes and wavelengths and quantifying the extent to which these waves are synchronized. The importance of a given wave is represented by its contribution to the explained variance of the time series. To illustrate its potential application to the study of movement, Fourier analysis was used to quantify the movement patterns of 2 pigeons on a variable-interval (VI) and a variable-time (VT) schedule of reinforcement. For comparison, the movements of 2 pigeons that did not receive reinforcement were similarly analyzed. Characteristic frequencies were higher during VI than during VT, and relatively low during nonreinforcement. We concluded that Fourier analysis can be used to represent movement patterns compactly, study their periodicity, stereotypy, and resonance, and assist in computer simulations and models of movement.  相似文献   
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Five hundred and fifty-eight cigarette smokers (mean 31 cigarettes/day) were randomized in four groups: Acupuncture, Behaviour Therapy, Placebo Medication and Waiting-list Control. The life-table analysis of smoking cessation showed, at a 12-month follow-up, no difference between Acupuncture, Behaviour Therapy and Placebo. Differences appeared only in an analysis of the abstinent subjects at each data point. Behaviour Therapy and Acupuncture accounted for significantly more abstinent subjects than Placebo at the end of the 2-week therapeutic phase. However at 9 and 12 months Acupuncture had a statistically-significant greater number of abstinent subjects than Behaviour Therapy, but there was no difference between Acupuncture and Placebo. The percentage decrease in smoking from baseline appeared significantly greater at 12 months in the first three groups than in the Control conditions. However, as in most smoking-cessation studies, the overall effect was small and non-specific. The results reflect the importance of maintenance programmes and of the prevention of addiction.  相似文献   
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