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941.
de Rijke  Maarten 《Studia Logica》2000,64(2):271-283
We introduce a notion of bisimulation for graded modal logic. Using this notion, the model theory of graded modal logic can be developed in a uniform manner. We illustrate this by establishing the finite model property and proving invariance and definability results.  相似文献   
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To gain insight into children's peer relations and their developmental significance, it is important to know not only how many relations children have but also to consider the structure of these relations. To demonstrate this, we used a multiple-study design in which we applied social network analyses to sociometric ratings and nominations from 1,082 4- to 5-year-old children in 83 school classes. Results showed that isolation in the classroom was more strongly associated with the choices that were given than those that were received. Gender plus the negative behavioral characteristics, aggressiveness and rejection, were the most important cues for social clustering. The structure of positive choices reflected the formation of friendship networks, whereas negative choices tended to be given directly to individual “problem” children. Finally, structure indices tapped aspects of children's relations that were not reflected in the traditional two-dimensional classification system and provided additional explanatory power for predicting developmental outcomes.  相似文献   
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The prospective study examines which factors assessed in pregnancy predispose mothers to seeing their newborn crying more as a problem and to more mental health problems in response to excessive baby crying. A total of 2140 pregnant women participated in the study, of which 1798 delivered a living singleton. Data was collected by means of a series of written questionnaires. The duration of the baby crying as well as the maternal reactions to the crying were assessed at a mean time of 1–2 months following delivery. The maternal reactions were related to several variables assessed at the end of the first trimester of pregnancy. Data was analysed by means of the method of stepwise multiple regression. Four factors were found to be associated with the reactions of mothers to newborn crying. These are: the duration of the crying, a first-born baby, a relatively high maternal age, and a relatively high score on ‘neuroticism’ in mothers. It was concluded that it is possible to indicate to a certain degree which mothers of excessive crying babies are prone to report more impact of the crying or more mental health symptomatology. It might be worthwhile to offer those mothers some extra support in order to try to prevent the situation from becoming worse. © 1998 John Wiley & Sons, Ltd.  相似文献   
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This study was aimed at assessing a new computer-based system to promote task performance in three adults with severe developmental disabilities. The new system, which was small and battery powered, could provide auditory and vibratory prompts in addition to pictorial instructions concerning the task steps. To control for the effects of the computer-based system, the subjects were also exposed to a card system. The results showed that the subjects had a significantly higher level of correct performance on the tasks presented with the computer-based system than on the tasks presented with the card system. Two of the subjects, moreover, seemed to prefer the computer-based system to the card system. © 1998 John Wiley & Sons, Ltd.  相似文献   
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