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131.
The story of the violence in Los Angeles, that was published in newspapers and visible on TV worldwide, was a horrifying spectacle that needs no retelling. A few facts will suffice: During the three days of disorder, 45 people died, 2,380 people were injured, and 9,500 were arrested. It was the most deadly civil disturbance in the United States in the 20th century. Rage was not limited to the poor and poverty stricken, but was felt throughout the entire African American community. Contrary to the initial television and newspaper reports, the first outbursts of anger occurred not in the poorest parts of black Los Angeles, but in some of its most stable, middle class black neighborhoods where a large percentage of homes are owned by their occupants. Also, it needs to be said that the looters and arsonists who acted out the anger and frustration of the black community were multi racial and a very small proportion of the effected population.  相似文献   
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133.
When modelling realistic systems, physical constraints on the resources available are often required. For example, we might say that at most N processes can access a particular resource at any moment, exactly M participants are needed for an agreement, or an agent can be in exactly one mode at any moment. Such situations are concisely modelled where literals are constrained such that at most N, or exactly M, can hold at any moment in time. In this paper we consider a logic which is a combination of standard propositional linear time temporal logic with cardinality constraints restricting the numbers of literals that can be satisfied at any moment in time. We present the logic and show how to represent a number of case studies using this logic. We propose a tableau-like algorithm for checking the satisfiability of formulae in this logic, provide details of a prototype implementation and present experimental results using the prover.  相似文献   
134.
This study investigated longitudinal pathways leading from early spatial skills in first-grade girls to their fifth-grade analytical math reasoning abilities (= 138). First-grade assessments included spatial skills, verbal skills, addition/subtraction skills, and frequency of choice of a decomposition or retrieval strategy on the addition/subtraction problems. In fifth grade, girls were given an arithmetic fluency test, a mental rotation spatial task, and a numeric and algebra math reasoning test. Using structural equation modeling, the estimated path model accounted for 87% of the variance in math reasoning. First-grade spatial skills had a direct pathway to fifth-grade math reasoning as well as an indirect pathway through first-grade decomposition strategy use. The total effect of first-grade spatial skills was significantly higher in predicting fifth-grade math reasoning than all other predictors. First-grade decomposition strategy use had the second strongest total effect, while retrieval strategy use did not predict fifth-grade math reasoning. It was first-grade spatial skills (not fifth-grade) that directly predicted fifth-grade math reasoning. Consequently, the results support the importance of early spatial skills in predicting later math. As expected, decomposition strategy use in first grade was linked to fifth-grade math reasoning indirectly through first-grade arithmetic accuracy and fifth-grade arithmetic fluency. However, frequency of first-grade decomposition use also showed a direct pathway to fifth-grade arithmetic reasoning, again stressing the importance of these early cognitive processes on later math reasoning.  相似文献   
135.
Crossmodal correspondences are a feature of human perception in which two or more sensory dimensions are linked together; for example, high-pitched noises may be more readily linked with small than with large objects. However, no study has yet systematically examined the interaction between different visual–auditory crossmodal correspondences. We investigated how the visual dimensions of luminance, saturation, size, and vertical position can influence decisions when matching particular visual stimuli with high-pitched or low-pitched auditory stimuli. For multidimensional stimuli, we found a general pattern of summation of the individual crossmodal correspondences, with some exceptions that may be explained by Garner interference. These findings have applications for the design of sensory substitution systems, which convert information from one sensory modality to another.  相似文献   
136.
Recent studies have shown evidence of positive concurrent relationships between children's use of text message abbreviations ('textisms') and performance on standardized assessments of reading and spelling. This study aimed to determine the direction of this association. One hundred and nineteen children aged between 8 and 12 years were assessed on measures of general ability, reading, spelling, rapid phonological retrieval, and phonological awareness at the beginning and end of an academic year. The children were also asked to provide a sample of the text messages that they sent over a 2-day period. These messages were analyzed to determine the extent to which textisms were used. It was found that textism use at the beginning of the academic year was able to predict unique variance in spelling performance at the end of the academic year after controlling for age, verbal IQ, phonological awareness, and spelling ability at the beginning of the year. When the analysis was reversed, reading and spelling ability were unable to predict unique variance in textism usage. These data suggest that there is some evidence of a causal contribution of textism usage to spelling performance in children aged 8-12 years. However, when the measure of rapid phonological retrieval (rapid picture naming) was controlled in the analysis, the relationship between textism use and spelling ability just failed to reach statistical significance, suggesting that phonological access skills may mediate some of the relationship between textism use and spelling performance.  相似文献   
137.
National belonging is often defined in terms of "ethnic" ancestry and "civic" commitment (with the latter typically implying a more inclusive conception of belonging). The authors report three Scottish studies manipulating the prominence of these criteria. In Study 1 (N = 80), a Chinese-heritage target was judged more Scottish (and his criticisms of Scotland better received) when Scotland was defined in civic terms. In Study 2 (N = 40), a similar manipulation in a naturalistic setting showed a civic conception of belonging resulted in more help being given to a Chinese-heritage confederate. Study 3 (N = 71) replicated Study 2 and showed the effect was mediated by judgments of the confederate's Scottishness. These studies emphasize the importance of exploring how ingroup identity is defined.  相似文献   
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139.
This paper illustrates how perception is achieved through interactions among the psychophysical functions of judged features of an object. The theory is that the perceiver places processed features in a multidimensional space of discriminal processes. Each dimension is scaled in units of discrimination performance. The zero coordinate of each feature is its level in an internal standard (norm) established by previous experience of that category of object in context. Experiments are reported which show that one, two, or three concurrent single-featured objects matched the multiple features of another object in two ways. Either stimulation from the two objects had discrimination distances from norm that added, or the stimulation by one object was processed through a concept describing stimulation by the other object. It follows that, in this case, perception via a receptor for the multi-featured object can be replaced by a point of balance among receptors for each single feature. The object with its own receptor is the gustatory stimulant L-glutamic acid as its monosodium salt. The features that stimulate diverse gustatory receptors of their own are sodium chloride, citric acid, sucrose, and caffeine. A more complex approach to dimensional coding was developed earlier for photoreceptors in colour judgments. The present approach is modality independent, mathematically simple, and economical in experimental data.  相似文献   
140.
SenseCam review has been shown to promote and sustain subsequent access to memories that might otherwise remain inaccessible. While SenseCam review facilitates recollection for personally experienced events, we know little about the boundary conditions under which this operates and about how underlying processing mechanisms can be optimally recruited to offset memory impairments of the sort that occur in dementia. This paper considers some of these issues with a view to targeting future research that not only clarifies our evolving body of theory about how memory works, but also informs about how memory-assistive technologies for patients might be employed to maximal effect. We begin by outlining key factors that are known to influence recollection. We then examine variability in the decline of memory function both in normal ageing and in dementia. Attention is drawn to similarities in the recollection deficits associated with depression and dementia, and we suggest that this may reflect shared underlying mechanisms. We conclude by discussing how one particular theoretical rationale can be intersected with key SenseCam capabilities to define priorities for ongoing and future SenseCam research.  相似文献   
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