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191.
192.
This paper describes an example of the successful formalization of quite advanced and new mathematics using the Mizar system. It shows that although much effort is required to formalize nontrivial facts in a formal computer deduction system, still it is possible to obtain the level of full logical correctness of all inference steps. We also discuss some problems encountered during the formalization, and try to point out some of the features of the Mizar system responsible for that. The formalization described in this paper allows also for contrasting the linguistic capability of the Mizar language and some of the phrases commonly used in “informal” mathematical papers that the Mizar system lacks, and consequently presents the methods of how to cope with it during the formalization. Yet, apart from the problems, this paper shows some definite benefits from using a formal computer system in the work of a mathematician.  相似文献   
193.
The theorem proving system Tps provides support for constructing proofs using a mix of automation and user interaction, and for manipulating and inspecting proofs. Its library facilities allow the user to store and organize work. Mathematical theorems can be expressed very naturally in Tps using higher-order logic. A number of proof representations are available in Tps, so proofs can be inspected from various perspectives.  相似文献   
194.
Comorbidity between antisocial behavior and depression in adolescence is widely recognized. This paper examines whether links with depressed mood differ among three subtypes of antisocial behavior: oppositionality, physical aggression and delinquency. In addition we examine two possible contributors to these links: negative life events that are dependent upon the individual's actions and depressogenic attributional style. Data are drawn from the G1219 large-scale community twin and sibling sample, and include 2409 questionnaire responses from youths aged between 13 and 19 living in the United Kingdom. Depressed mood was independently associated with both oppositionality and delinquency, but not with physical aggression. Dependent negative life events were strongly implicated in the association between delinquency and depressed mood, whereas depressogenic attributional style was implicated in the associations of both oppositionality and delinquency with depressed mood. Oppositionality remained a significant predictor of depressed mood after accounting for attributional style and life events whereas delinquency did not. The pattern of associations was largely similar in boys and girls. We discuss these results in terms of developmental models of the links between antisocial behavior and depressed mood.  相似文献   
195.
This study examined sex differences in risk factors associated with adolescent depression in a large sample of boys and girls. Moderation and mediation explanatory models of the sex difference in likelihood of depression were examined. Findings indicate that the factors associated with depression in adolescent boys and girls are quite similar. All of the variables considered were associated with depression, but sex did not moderate the impact of vulnerability factors on likelihood of depression diagnosis. However, negative self-perceptions in the domains of achievement, global self-worth, and physical appearance partially mediated the relationship between sex and depression. Further, girls had higher levels of positive self-perceptions in interpersonal domains that acted as suppressors and reduced the likelihood of depression in girls. These findings suggest that girls' higher incidence of depression is due in part to their higher levels of negative self-perceptions, whereas positive interpersonal factors serve to protect them from depressive episodes.  相似文献   
196.
Two experiments were conducted to determine the visual span of detection and recognition of the kanji character embedded in a horizontal row of random hiragana characters. An independent variable was the visual complexity of the kanji characters: simple and complex. In Experiment 1, visual spans of detection were determined by a staircase method. Values of visual spans were more than 15 character spaces for the complex kanji characters, and ranged from 4 to 10 character spaces (mean 7.6) for the simple kanji characters. In Experiment 2, visual spans of recognition were determined by an ascending series of limits method. Values of visual spans ranged from 0 to 4 character spaces (mean 2.3) for the complex kanji characters and from 3 to 7 character spaces (mean 4.8) for the simple kanji characters. These results are discussed in relation to reading of Japanese kanji-kana mixed texts.  相似文献   
197.
In many longitudinal studies, self‐esteem has been shown to increase up until around age 50 or 60 and to decrease thereafter. These studies have also found substantial inter‐individual differences in the intra‐individual development of self‐esteem. In the current study, we examined whether this variation in change could be attributed to underlying latent classes of individuals following different trajectories of self‐esteem development over time. By applying general growth mixture modelling to data from the representative German pairfam study (N = 12 377), four latent classes of self‐esteem development across five years were extracted. Based on their mean levels, trajectories, and variability, individuals in the latent classes could be described as having (a) constant and stable high self‐esteem (29.00% of the sample), (b) constant but variable moderate self‐esteem (31.69%), (c) increasing and stabilizing self‐esteem (15.13%), and (d) decreasing and variable self‐esteem (24.18%). Furthermore, these latent classes differed in accordance with findings of prior research on self‐rated, partner‐rated, and objective correlates of the domains of health and well‐being, partner relationships, and occupational status. Thus, the current study shows that inter‐individual variation in intra‐individual change in self‐esteem is not random but reflects specific individual trajectories, or pathways, of self‐esteem. Copyright © 2016 European Association of Personality Psychology  相似文献   
198.
从寿命研究的历史轨迹和令人瞩目的成就着重论述了寿命学已经发展成熟,成为独立的学术体系并进一步从寿命进化的历程中探讨寿命形成的原因,指出氧的决定性作用,为提高生命质量,延长寿命提供科学依据。  相似文献   
199.
论寿命学:2.梦想与现实   总被引:1,自引:0,他引:1  
以人类最大寿命的相对有限性为基础,论述现阶段延长人类寿命面临的问题以及人类最大寿限演化的远景并着重指出依靠现行医疗模式延寿潜力的有限性以及改变医疗保健观念与运行体系的必要性。  相似文献   
200.
By means of the moving window paradigm, we examined how many letters can be identified during a single eye fixation and whether this letter identity span changes as a function of reading skill. The results revealed that 8-year-old Finnish readers identify approximately 5 characters, 10-year-old readers identify approximately 7 characters, and 12-year-old and adult readers identify approximately 9 characters to the right of fixation. Comparison with earlier studies revealed that the letter identity span is smaller than the span for identifying letter features and that it is as wide in Finnish as in English. Furthermore, the letter identity span of faster readers of each age group was larger than that of slower readers, indicating that slower readers, unlike faster readers, allocate most of their processing resources to foveally fixated words. Finally, slower second graders were largely not disrupted by smaller windows, suggesting that their word decoding skill is not yet fully automatized.  相似文献   
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