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101.
The influence of ruthenium (Ru) on the partitioning behavior of W, Re and Cr in γ′-Ni3Al has been studied using the Dmol3 method based on the density functional theory. The calculated results show that W, Re and Cr have a preference for the Ni site in γ′-Ni3Al alloyed with Ru. When Ru substitutes the central Ni atom, the site preference for W, Re and Cr varies. Furthermore, an electronic structure analysis of the alloy in terms of the Mulliken population and partial density of states was performed to elucidate the alloying mechanism of Ru in γ′-Ni3Al. The results show that the strengthening effect of Ru in the alloy arises from a reduction in the binding energy of Ru as well as p-orbital hybridization between Ru and the host atoms.  相似文献   
102.
A multi-mode deformation model is used in a molecular dynamics simulation of nanocrystalline copper. Abundant deformation twin lamellae are developed by shearing the following compression to the elastic limit. Deformation twins (DTs) nucleate through two different mechanisms facilitated by Shockley partial slips. Interactions between DTs and Shockley partials are observed in this simulation.  相似文献   
103.
Although our ability to remember future simulations conveys an adaptive advantage, enabling us to better prepare for upcoming events, the factors influencing the memorability of future simulations are not clear. In this study, participants generated future simulations that combined specific people, places and objects from memory, and for each trial, made a series of phenomenological ratings about the event components and the simulation as a whole. Memory for simulations was later assessed using a cued-recall test. We used multilevel modelling to determine whether the phenomenological qualities of event components (familiarity, emotionality and significance) and simulations (detail, plausibility) were predictive of whether the simulation was successfully encoded and later accessible. Our results demonstrate that person familiarity, detail and plausibility were significant predictors of whether a given future simulation was encoded into memory and later accessible. These findings suggest that scaffolding future simulations with pre-existing episodic memories is the path to a memorable future.  相似文献   
104.
Strength training is often prescribed for children with cerebral palsy (CP); however, links between strength gains and mobility are unclear. Nine children (age 14?±?3?years; GMFCS I-III) with spastic CP completed a 6-week strength-training program. Musculoskeletal gait simulations were generated for four children to assess training effects on muscle forces and function. There were increases in isometric joint strength, but no statistical changes in fast-as-possible walking speed or endurance after training. The walking simulations revealed changes in muscle forces and contributions to body center of mass acceleration, with greater forces from the hip muscles during walking most commonly observed. A progressive strength-training program can result in isometric and dynamic strength gains in children with CP, associated with variable mobility outcomes.  相似文献   
105.
The present study investigated potential sex differences in preferences for spicy, hot or unusual foods and in food aversions or neophobia. This study also reexamined the issue of a gender difference in preference for sweet foods. Questionnaires concerning past and current food use and preferences as well as food and condiment use in one actual meal were completed by 148 people between 17 and 32 years of age. Their responses clearly support the prediction that men tend to have a stronger preference than women for spicy, hot foods. The results also support the prediction that men are more likely than women to seek unusual and new foods. Both sexes showed the same degree of preference for condiment use.  相似文献   
106.
黎光明  张敏强 《心理科学》2013,36(1):203-209
方差分量估计是概化理论的必用技术,但受限于抽样,需要对其变异量进行探讨。采用Monte Carlo数据模拟技术,探讨非正态数据分布对四种方法估计概化理论方差分量变异量的影响。结果表明:(1)不同非正态数据分布下,各种估计方法的“性能”表现出差异性;(2)数据分布对方差分量变异量估计有影响,适合于非正态分布数据的方差分量变异量估计方法不一定适合于正态分布数据。  相似文献   
107.
目前参数估计多采用统计方法,存在耗时长、要求被试样本容量大和项目数多等缺点。本文将BP神经网络和降维法相结合,对GRM的项目参数和考生能力参数进行估计。蒙特卡洛模拟结果显示:(1)不管是人多题少还是题多人少,该网络设计下的参数估计精度都较高;(2)可以应用到多个不同等级评分的参数估计中,甚至是超过15个等级的项目参数,估计精度也较高,这是其他参数估计方法所不可比拟的;(3)运行的时长和统计估计方法相比大大缩减。  相似文献   
108.
This study evaluated the effectiveness of a brief integrated theory-based intervention to increase physical activity (PA) among adolescents over a three-month follow-up period. A 2 (mental simulation: present vs. absent) × 2 (action planning: present vs. absent) × 4 (time: baseline vs. one-month vs. two-month vs. three-month follow-up) mixed-model randomized controlled design was adopted. Adolescents aged 14–15 years (N = 267) completed baseline psychological measures and self-reported PA followed by the relevant intervention manipulation, if appropriate, with follow-up measures collected one, two, and three months later. Results revealed no significant effects for the mental simulation and action planning strategies nor the interaction of the two strategies. However, among participants with low levels of baseline PA, participants in both mental simulation alone and action planning alone groups reported significantly higher levels of PA at one-month follow up than other groups, suggesting that individual intervention components may be effective in low-active adolescents.  相似文献   
109.
采用自定步速阅读方法与图片核证范式(picture verification paradigm)探讨状态不确定独立否定句(如“裙子不是红色的”)的动态表征过程, 包括3个实验。结果发现:(1)在否定加工的初期, 即250 ms间隔时间条件下, 读者表征事件的否定状态; 肯定句已经通达事件的实际状态。(2)在否定加工的中期, 即750 ms间隔时间条件下, 读者仍然表征事件的否定状态, 但已开始对事件的备择选项进行搜索; 肯定句仍然保持对事件实际状态的表征。(3)在否定加工的后期, 即1500 ms间隔时间条件下, 读者表征否定标记与事件的否定状态, 同时完成对备择选项的搜索; 肯定句依旧保持对事件实际状态的表征。据此, 本文提出的锚激活与限制满足模型(anchor-based activation and satisfaction constrained model)得到初步证明。  相似文献   
110.
Previous studies have shown that object properties are processed faster when they follow properties from the same perceptual modality than properties from different modalities. These findings suggest that language activates sensorimotor processes, which, according to those studies, can only be explained by a modal account of cognition. The current paper shows how a statistical linguistic approach of word co-occurrences can also reliably predict the category of perceptual modality a word belongs to (auditory, olfactory-gustatory, visual-haptic), even though the statistical linguistic approach is less precise than the modal approach (auditory, gustatory, haptic, olfactory, visual). Moreover, the statistical linguistic approach is compared with the modal embodied approach in an experiment in which participants verify properties that share or shift modalities. Response times suggest that fast responses can best be explained by the linguistic account, whereas slower responses can best be explained by the embodied account. These results provide further evidence for the theory that conceptual processing is both linguistic and embodied, whereby less precise linguistic processes precede precise simulation processes.  相似文献   
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