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281.
We report the mechanical properties and microstructures of titanium-microalloyed interstitial-free (IF) steels with different carbon contents smelted and rolled in the laboratory. The results show an increase of yield strength and tensile strength with carbon content, which are enhanced with lower coiling temperature (CT). Microstructure analysis reveals that the ferrite grain size varies from 11 to 23?μm, while the average size of TiC as the main second-phase particle ranges from 10 to 35?nm. The sample with 80?ppm carbon and 853?K CT reaches a mechanical strength close to that of high-strength IF steels. The increase of yield strength is mainly attributed to both grain-refining and precipitation strengthening.  相似文献   
282.
Eye movements were measured to examine whether item-method directed forgetting involved a spatial overt attention shift. Experiment 1 showed that participants’ eyes were moved away from the study word following the forget and ignore cues, but not the remember cue. Experiment 2 revealed that the eyes were moved away from the area that covered by the study word even when the study word disappeared upon the presentation of the memory cue. Both the study word and memory cue were presented auditorily in Experiment 3. In all experiments, the to-be-remembered words were recalled better than both to-be-forgotten and to-be-ignored words. More importantly, mental effort, as indexed by the pupil size, increased following the remember, as compared with the forget and ignore cues. These findings are discussed in terms of controlling spatial overt attention after encoding to withdraw attention from irrelevant information and to allocate cognitive resources to relevant information for long-term retention.  相似文献   
283.
This article is a reply to Kagan’s (in press) commentary on our earlier article (Luke & Banerjee, 2013), which presented a meta-analysis and systematic review of research on the links between childhood maltreatment and social understanding. We address Kagan’s comments about the depiction of maltreatment as an isolated independent variable, and consider the specific obstacles faced by researchers in this area when seeking to understand the role played by social–contextual factors. We also consider how Kagan’s extension of our argument about heterogeneity in maltreated samples might usefully be applied to future research with this vulnerable group.  相似文献   
284.
A series of tensile and microbend tests were conducted on aluminium single-crystal foil specimens with different thicknesses ranging from 20 to 90?µm. Two different crystal orientations relative to the tensile direction were considered in the tests: one is an orientation that was excepted to activate at least four slip systems on four different slip planes, and the other is an orientation that was expected to activate only a single-slip system. In the tensile tests, typical size dependence of initial yield strength was observed. The microbend test method was extended to include a reversal of bending direction. Using the curves of bending moment normalized by the square of foil thickness versus surface strain, which were obtained from the reversed bending tests, the total amounts of strain hardening were divided into isotropic and kinematic hardening components. In the microbend tests, a pronounced size-dependent kinematic hardening behaviour was clearly observed; meanwhile, the amounts of isotropic hardening were very small, particularly for the single-slip orientation.  相似文献   
285.
The visual system summarizes average properties of ensembles of similar objects. We demonstrated an adaptation aftereffect of one such property, mean size, suggesting it is encoded along a single visual dimension (Corbett, et al., 2012), in a similar manner as basic stimulus properties like orientation and direction of motion. To further explore the fundamental nature of ensemble encoding, here we mapped the evolution of mean size adaptation over the course of visually guided grasping. Participants adapted to two sets of dots with different mean sizes. After adaptation, two test dots replaced the adapting sets. Participants first reached to one of these dots, and then judged whether it was larger or smaller than the opposite dot. Grip apertures were inversely dependent on the average dot size of the preceding adapting patch during the early phase of movements, and this aftereffect dissipated as reaches neared the target. Interestingly, perceptual judgements still showed a marked aftereffect, even though they were made after grasping was completed more-or-less veridically. This effect of mean size adaptation on early visually guided kinematics provides novel evidence that mean size is encoded fundamentally in both perception and action domains, and suggests that ensemble statistics not only influence our perceptions of individual objects but can also affect our physical interactions with the external environment.  相似文献   
286.
287.
Several reaction time (RT) studies report faster responses when responses to temporal information are arranged in a spatially congruent manner than when this arrangement is incongruent. The resulting space–time congruency effect is commonly attributed to a culturally salient localization of temporal information along a mental timeline (e.g., a mental timeline that runs from left to right). The present study aims to provide a compilation of the published RT studies on this time–space association in order to estimate the size of its effect and the extent of potential publication bias in this field of research. In this meta‐analysis, three types of task are distinguished due to hitherto existing empirical findings. These findings suggest that the extent to which time is made relevant to the experimental task has a systematic impact on whether or not the mental timeline is activated. The results of this meta‐analysis corroborate these considerations: First, experiments that make time a task‐relevant dimension have a mean effect size of = 0.46. Second, in experiments in which time is task irrelevant, the effect size does not significantly deviate from zero. Third, temporal priming studies have a surprisingly high mean effect size of = 0.47, which, however, should be adjusted to = 0.36 due to publication bias.  相似文献   
288.
工作记忆中央执行成分在计算加工的诸多过程中发挥重要影响。以82名大学生为被试,采用双任务实验范式考察工作记忆中央执行成分对估算表现的影响。结果发现:1)估算过程需要中央执行成分的参与,增加中央执行成分负荷会导致估算准确率下降;2)无论是否增加中央执行负荷,问题大小效应在估算中均不明显;3)乘法个位数大小顺序会影响估算值的准确性,在有中央执行负荷时数字顺序效应明显。  相似文献   
289.
Dutch adults from a nationwide Internet panel (N = 426) were asked to imagine that their next‐door neighbours would move out and that people with intellectual disability would move in. Severity of disability and group size were varied to manipulate intergroup threat. These two factors independently influenced social acceptance and a variety of emotional and behavioural measures. In particular, it was found that a large group with severe disability aroused the strongest negative response, whereas a small group with mild disability aroused the weakest negative response. Small groups with a severe disability and large groups with a mild disability aroused similar and intermediate negative responses. Results are discussed in terms of theories of intergroup threat and stigmatisation. Practical implications for predicting the success of de‐institutionalisation and social integration of groups with special needs are addressed. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
290.
To explore the effects of various categorization strategies on intergroup bias within and beyond a contact situation, two experiments were conducted involving groups of different size and/or status that worked together on a cooperative task. Three categorization strategies (decategorization, recategorization, and dual identity) were compared, and bias was measured through symbolic reward allocations to people who were and were not actually encountered. In Experiment 1 (N = 129), we varied group size (minority or majority) and found that it affected bias within the contact situation—minority groups were more biased than majority groups. All of the categorization strategies limited bias and they did so equally well. Outside the contact situation, however, only the recategorization and dual identity strategies limited bias. In Experiment 2 (N = 156), we varied both group status (low or high) and group size. Both of these variables affected bias within the contact situation—high status groups were more biased than low status groups, and minority groups were again more biased than majority groups. Once again, all three categorization strategies limited bias and they did so equally well. Outside the contact situation, however, an interaction among the independent variables was observed. For minority groups, only the dual identity strategy limited bias, but none of the categorization strategies limited bias for majority groups.  相似文献   
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