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41.
In the current paper we consider theories with vocabulary containing a number of binary and unary relation symbols. Binary relation symbols represent labeled edges of a graph and unary relations represent unique annotations of the graph’s nodes. Such theories, which we call annotation theories, can be used in many applications, including the formalization of argumentation, approximate reasoning, semantics of logic programs, graph coloring, etc. We address a number of problems related to annotation theories over finite models, including satisfiability, querying problem, specification of preferred models and model checking problem. We show that most of considered problems are NPTime- or co-NPTime-complete. In order to reduce the complexity for particular theories, we use second-order quantifier elimination. To our best knowledge none of existing methods works in the case of annotation theories. We then provide a new second-order quantifier elimination method for stratified theories, which is successful in the considered cases. The new result subsumes many other results, including those of [2, 28, 21].  相似文献   
42.
We motivate and introduce a new method of abduction, Matrix Abduction, and apply it to modelling the use of non-deductive inferences in the Talmud such as Analogy and the rule of Argumentum A Fortiori. Given a matrix \({\mathbb {A}}\) with entries in {0, 1}, we allow for one or more blank squares in the matrix, say a i,j =?. The method allows us to decide whether to declare a i,j = 0 or a i,j = 1 or a i,j =? undecided. This algorithmic method is then applied to modelling several legal and practical reasoning situations including the Talmudic rule of Kal-Vachomer. We add an Appendix showing that this new rule of Matrix Abduction, arising from the Talmud, can also be applied to the analysis of paradoxes in voting and judgement aggregation. In fact we have here a general method for executing non-deductive inferences.  相似文献   
43.
The present study assessed the relations between basic motor abilities in kindergarten and scholastic, social, and emotional adaptation in the transition to formal schooling. Seventy‐one five‐year‐old kindergarten children were administered a battery of standard assessments of basic motor functions. A year later, children's adjustment to school was assessed via a series of questionnaires completed by the children and their class teachers. The results indicate that in addition to the already documented association between visual–motor integration and academic achievement, other motor functions show significant predictive value to both scholastic adaptation and social and emotional adjustment to school. The results further suggest a better prediction of scholastic adaptation and level of disruptive behaviour in school when using an aggregate measure of children's ability in various motor domains than when using assessments of singular motor functions. It is concluded that good motor ability may serve as a buffer to the normative challenges presented to children in the transition to school. In contrast, poor motor ability emerges as a vulnerability factor in the transition to formal schooling. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
44.
The texel pair represents a dilemma in texture discrimination because, despite having the same component orientations, discrimination is still possible (Julesz, 1981), showing a performance asymmetry. Other possible element properties that could influence this task are line terminations, closure, and the size of these elements. We found that line terminators are critical for the task; however, results from double-task experiments indicated that terminator-based discrimination requires the use of attention. When attention is not available for the task, “size” of the elements (with the considered slightly larger) seems to be critical for this discrimination and for the asymmetric performance. To generalize the concept of “size” to textures in general, further experiments were performed with textures of different-sized elements. Results showed, as past literature has indicated, that there is a performance asymmetry, with the larger of the elements being more visible when in the foreground. This asymmetry was additionally shown to reverse itself (i.e., the smaller element became the more visible) as the scale of the elements increased (while interelement distance remained fixed). A filter analysis was developed in order to measure the apparent size of these elements within textures (texsize), defined as the response weighted average of the filter wavelength, $\bar \lambda $ , for a group of elements. The calculation of $\bar \lambda $ was attained by introducing a nonlinearity after the second stage of filtering (or spatial averaging of filter responses). This analysis showed high correlation between the texture with the larger $\bar \lambda $ and the more visible texture. On the basis of this correlation, a wavelength-dependent noise is proposed, having more internal noise for low-spatial-frequency filters and less for high-spatial-frequency filters.  相似文献   
45.
Concrete operational Ss were provided empirical evidence of nonconservation of discontinuous quantity and weight. The findings were that few Ss accepted this evidence. This was interpreted as supporting the organismic-developmental claim that lower forms of reasoning are transformed into structurally more advanced forms. It was also found that (1) probing provides a more accurate assessment of Ss' operational levels, (2) one can empirically distinguish between logicomathematical and physical knowledge, and (3) the former is understood by Ss to be nomically necessary and the latter, in the case of weight, may not be.  相似文献   
46.
OBJECTIVE: To develop a predictive model of the lift-off event during chair rise in healthy subjects, using foot-floor reaction forces. BACKGROUND: An important event during chair rise is lift-off from the seat: the transition from the inherently stable three-point contact to the unstable two-point contact. There is no consistent or generally agreed upon method for estimating the time of lift-off when an instrumented seat is unavailable. METHODS: Twenty healthy volunteers were divided into a testing set and training set. Each subject performed repeated chair rise trials at different speeds. Seat-floor and foot-floor forces, recorded with two force platforms, were used to develop a model of the lift-off event. RESULTS: The magnitude of the vertical foot-floor reaction at lift-off (F0VF) was linearly related (R2 = 0.71, P < 0.001) to the peak vertical foot-floor reaction force (FMVF). A linear model was developed for the training group, which enabled prediction of lift-off time for the testing group with an absolute average error of 6 ms (about 1 data frame at 150 Hz). The linear model derived for the entire sample was: F0VF = 28.14 + FMVF * (0.6434). CONCLUSIONS: The lift-off event for healthy subjects performing chair rise can be accurately predicted from foot-floor reaction forces, without requiring an instrumented seat.  相似文献   
47.
Freeman E  Sagi D  Driver J 《Perception》2004,33(2):181-194
Elements of a contour are often easier to detect when they possess collinearity, with their local orientations matching the global orientation of the contour. We recently reported attentional modulation of such lateral interactions between a central near-threshold target Gabor patch and flanking high-contrast patches (Freeman et al, 2001 Nature Neuroscience 4 1032-1036). Here, we examined whether such attentional effects reflect specific modulation of mechanisms sensitive to collinear configurations, or instead more general modulation of sensitivity to either the global or local orientation-components of the stimulus. Thresholds for detecting a central Gabor target were measured, while observers also judged the Vernier alignment between one pair of flankers and ignored a second flanker pair (when present). Target contrast-thresholds were facilitated only when attending collinear flankers. There was no facilitation when attending flankers that shared only local orientation with the target, or flankers that fell on a global axis aligned with target orientation but having orthogonal local orientation. Ignored collinear flankers had no effect on target thresholds. These results demonstrate strong and specific attentional modulation of contour-integration mechanisms in early vision sensitive to collinear configurations.  相似文献   
48.
Previous research has indicated that jealousy is one of the major triggers of domestic violence. Three studies here examined North Americans' ambivalent feelings about jealousy and jealousy-related aggression. In Study 1, it was shown that participants believed both that jealousy can be a sign of insecurity and a sign of love. In Study 2, it was shown that this equating of jealousy with love can lead to the tacit acceptance of jealousy-related violence. In Study 3, it was shown that a relative acceptance of jealousy-related aggression extends to cases of emotional and sexual abuse by husbands against their wives. In both Studies 2 and 3, men who hit or abused their wives over a jealousy-related matter were judged to romantically love their wives as much as those who did not engage in abuse. Violence in the context of a non-jealousy-related argument was seen quite negatively, but it lost a great deal of its negativity in the jealousy case.  相似文献   
49.
Two studies explored how domestic violence may be implicitly or explicitly sanctioned and reinforced in cultures where honor is a salient organizing theme. Three general predictions were supported: (a) female infidelity damages a man's reputation, particularly in honor cultures; (b) this reputation can be partially restored through the use of violence; and (c) women in honor cultures are expected to remain loyal in the face of jealousy-related violence. Study 1 involved participants from Brazil (an honor culture) and the United States responding to written vignettes involving infidelity and violence in response to infidelity. Study 2 involved southern Anglo, Latino, and northern Anglo participants witnessing a "live" incident of aggression against a woman (actually a confederate) and subsequently interacting with her.  相似文献   
50.
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