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311.
The growth of austenite from a mixture of ferrite and cementite in low-alloy steels can be classified into three temperature ranges above the eutectoid temperature. In the first range, the austenite growth and cementite dissolution are controlled by alloy element diffusion from the beginning. In the second, they are controlled by carbon diffusion and switch to alloy element diffusion control at a later stage. In the third, the cementite dissolution, if the ferrite matrix has transformed to austenite upon heating, is controlled by carbon diffusion until completion. The transition temperatures between these ranges are evaluated in a quaternary alloy containing Mn and Cr by Thermo-calc and DICTRA simulation, and are in essential agreement with earlier experimental results. The proposed simple approach of calculating the transition temperatures may facilitate our understanding of austenitization kinetics and the design of heat treatment, for example, homogenization and soaking, of high-carbon steels. 相似文献
312.
The role of working memory (WM) and inhibition in mental set shifting was examined from an individual difference perspective in children aged 5–14 years (N = 117). Using the Hearts and Flowers task the rationale of the present study was to directly test the theoretical assumption that mental set shifiting in childhood primarily builds on WM and inhibitory processes. Theoretical predictions about WM and inhibitory demands in the congruent and incongruent conditions of the Hearts and Flowers task were also considered because these blocks underlie relevant measures of set shifting. The findings show that both WM and inhibition (extracted as factors in confirmatory factor analysis) are important for set shifting but that this general association is driven by the link between these executive functions (EFs) and the goal‐representation aspect (i.e. global switch costs) of shifting, rather than to the actual switch‐implementation process (i.e. local switch costs). In addition, our findings are novel in showing that, despite a substantial correlation between the two EF components, it was the variance specific to WM and inhibition that was important for mental set shifting. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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The evaluation of pedestrian comfortability is important for the construction and management of walkable spaces. Pedestrian level-of-service (LOS), which is mostly categorized by density, has been widely applied and is believed to be capable of indicating the comfortability of the crowd. However, there is a lack of evidence that physically measured LOS reflects psychological comfortability, let alone the comparison between the performances of different candidate indicators, including the velocity and different local densities. Here, we show that walking velocity depicts pedestrian perceived congestion more accurately than density. In our experiments on pedestrians in a room-egress scenario with an inner obstacle, we obtained objective physical trajectory data from video analysis as well as subjective perception data from a questionnaire survey. The performance of the velocity and four types of local densities in reproducing pedestrian perceptions were numerically evaluated. We found that the velocity outperformed the local density. The lower performance of local densities was mainly caused by the pedestrians located at the back of the crowd, who walked at lower velocities and perceived higher congestion, despite their lower local densities that would correspond to less crowdedness from a physical viewpoint. Besides, the perceived congestion of pedestrians was shown to be affected by the initial pedestrian positions at the crowd, the obstacle layout, and the pedestrians’ age and gender. Furthermore, we suggest that the larger the gap between the desired and actual velocities, the larger the extent of the perceived congestion. We expect that our findings will contribute to a more accurate evaluation of pedestrian comfortability, which could help improve the walkable spaces of various infrastructures. 相似文献
316.
Alongside human factors, contextual factors are believed to have an ongoing and complex impact on driving outcomes. However, how and to what extent the components of context influence driving outcomes (e.g. rule violations, crash, stress, fatigue) are far beyond full understanding. The purpose of this study is to explore the effects of weather condition, lighting condition and traffic density on driving outcomes. Thirty-six volunteers were enrolled to participate into a driving simulator-based experiment. Each participant was required to complete twelve trials of simulated driving under different sets of scenarios. Driving outcome was measured by five dependent variables: frequency of speeding, frequency of lane deviations, number of correct sign recognition, completion time and workload. The results showed the frequency of speeding was significantly affected by weather condition, lighting condition and traffic density. Lighting condition had a significant effect on number of correct sign recognition. Weather condition, lighting condition and traffic density had significant effects on task completion time. Weather condition and lighting condition had significant effects on driver’s workload. The implications of the results could help traffic safety professionals better understand the risk factors that may lead to human errors during driving. Practically, countermeasures could be inspired and developed to mitigate the adverse impacts brought by driving context to minimum. 相似文献
317.
通过四个实验考察句子边界对整体连贯性的影响。实验运用不一致程序(inconsistent paradigm)进行。实验一结果发现,当目标行1(target line)不是一个完整句子时,被试阅读完目标行2(post-target line)后才会意识到目标行1中的不一致。实验二结果发现,当目标行1是一个完整句子时,被试阅读完目标行1后就可立刻意识到其中的不一致,但探测词的反应时在两种条件下则并没有明显差异。这两个实验的结果表明,句子边界作为一种信号,提示读者在阅读下一句子前要完成当前句子的整合加工。实验三结果发现,目标行1以一个无关词(如然后)结束时,被试阅读完目标行1后也可立刻注意到其中的不一致,这表明句号对背景信息的整合不是必需的。实验四考察了分号的作用,结果显示:被试阅读完目标行1后并没有意识到其中的冲突。根据本研究的结果,可以推测句号在理解过程中起着重要影响,而其它句子边界(如:分号)的作用则并不明显。 相似文献
318.
Julia Martínez-Ariño 《宗教、国家与社会》2019,47(4-5):364-373
ABSTRACTThis collection addresses the question of how cities govern and regulate religious diversity. Its main goals are: 1) to take stock of current research regarding the municipal governance of religious diversity; 2) to put forward new concepts and empirical analyses to enhance this field of study; and 3) to identify potential lines for future enquiry that help move the field forward. The contributions cover a wide variety of topics, such as the roles of laws, state contracts, and urbanism in governing religious diversity, comparisons of diverging governance trajectories in various cities within one country, and the controversies surrounding the celebration of religious events in urban spaces. The contributions also identify factors that influence governance processes at the urban level and their consequences for the practice of religion. The collection covers studies of cities in various European countries as well as in Canada. 相似文献
319.
Shenli Peng Chang Hong Liu Xiaofan Yang Haojian Li Wenfeng Chen 《Visual cognition》2020,28(3):180-191
ABSTRACT Research has shown that observers often spontaneously extract a mean representation from multiple faces/objects in a scene even when this is not required by the task. This phenomenon, now known as ensemble coding, has so far mainly been based on data from Western populations. This study compared East Asian and Western participants in an implicit ensemble-coding task, where the explicit task was to judge whether a test face was present in a briefly exposed set of faces. Although both groups showed a tendency to mistake an average of the presented faces as target, thus confirming the universality of ensemble coding, East Asian participants displayed a higher averaging tendency relative to the Westerners. To further examine how a cultural default can be adapted to global or local processing demand, our second experiment tested the effects of priming global or local processing orientation on ensemble coding via a Navon task procedure. Results revealed a reduced tendency for ensemble coding following the priming of local processing orientation. Together, these results suggest that culture can influence the proneness to ensemble coding, and the default cultural mode is malleable to a temporary processing demand. 相似文献
320.
Oluwatoyin Dare Kolawole 《Science as culture》2019,28(3):391-401
ABSTRACTThe contestation between mainstream science and counter-science is a longstanding phenomenon. The current issue of Science as Culture addresses the need for scientists to consciously engage in a broad-spectrum science that simultaneously focuses its lens on the social and natural dimensions of the universe. The question of how this objective can be achieved by Science and Technology Studies (STS) scholars is, therefore, the main thrust of this special issue. 相似文献