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41.
Previous research on stereotype threat in children suggests that making gender identity salient disrupts girls' math performance at as early as 5 to 7 years of age. The present study (n = 124) tested the hypothesis that parents' endorsement of gender stereotypes about math moderates girls' susceptibility to stereotype threat. Results confirmed that stereotype threat impaired girls' performance on math tasks among students from kindergarten through 2nd grade. Moreover, mothers' but not fathers' endorsement of gender stereotypes about math moderated girls' vulnerability to stereotype threat: Performance of girls whose mothers strongly rejected the gender stereotype about math did not decrease under stereotype threat. These findings are important because they point to the role of mothers' beliefs in the development of girls' vulnerability to the negative effects of gender stereotypes about math. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
42.
Threatening things are often perceptually exaggerated, such that they appear higher, closer, of greater duration, or more intense than they actually are. According to the Resources and Perception Model (RPM) psychosocial resources can prevent this exaggeration, leading to more accurate perception. Two studies tested RPM. Study 1 showed that the perceived closeness of a threatening object (a live tarantula) but not an innocuous object (a cat toy) was moderated by induced self-worth. Further, the more self-worth that participants experienced, the less close the tarantula appeared to them. Study 2 showed that greater levels of self-esteem reduced perceived height, but only among participants prevented from holding a protective handrail while looking down. Together, these studies confirm that resources moderate the physical perception of both distance and height, that resources moderate perception of threats but not nonthreats, that different resources have similar moderating effects, and that psychosocial resources can supplant physical resources. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
43.
44.
为解决在目标威胁评估方法中,确定各属性的权重时受主观因素和高机动目标影响大的问题,提出一种 改进的多属性决策目标威胁评估方法。综合模糊理论和多属性决策理论,通过构造隶属度函数规范化属性值,基于 熵值法求解属性权重,应用TOPSIS 理论进行目标威胁评估,构建不同的态势实例,采用静态数值计算和动态模拟 仿真的方法对算法进行验证。仿真实验结果验证了该方法的合理性和有效性。  相似文献   
45.
This paper presents an investigation into spatial risk differences over small distances for the Helicobacter pylori infection in the city of Leipzig, Germany and two rural districts. A model, using Bayesian inference, was developed that adjusts the risk for individual-specific factors, and for spatial or individual over-dispersion, respectively. Additionally, the model takes into account conditional spatial autocorrelation. We found a significant positive association to the H. pylori infection risk for: “more than three children live in the household” (OR = 2.4, p = 0.001), “more persons live per sq.m than average” (OR = 1.4, p = 0.03), “home situated at main road” (OR = 1.4, p = 0.04) and “using well water” (OR = 2.3, p = 0.05). A protective effect was identified for “travelled to low prevalence region” (OR = 0.4, p < 0.0001) and “born in Germany” (OR = 0.2, p < 0.0001). Three administrative areas with significantly increased spatial risk were identified: one in the rural district and two in the city of Leipzig. The model explained 24.9% of the total deviance. Contrary to expectations, the largest part of deviance of the data was not explained by the identified significant risk factors, but by individual-specific heterogeneities. We conclude that further - so far not discussed - factors influence the risk and the spatial variation of the H.pylori infection. Furthermore, from the results we speculate about a possible impact of long-time air pollution and surface water.  相似文献   
46.
In this paper, a disturbance‐decoupled adaptive observer is designed for the joint state‐parameter estimation of a system with unknown disturbance inputs. The proposed Robust Adaptive Observer (RAO) integrates an Unknown Input Observer (UIO) to the parameter estimation process, where the unknown parameters are estimated as extended states of the system. An auxiliary input is added to the UIO in coping with the estimation errors so that the exponential stability and convergence of the observer are guaranteed. The proposed observer is applied to a hydraulically driven elevator for the faulty parameter estimation. The simulation results show the accuracy of the observer and its robustness to both disturbances and measurement noises. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
47.
进行了苯巴比妥的合成工艺研究,探讨了甲醇钠滴加温度、甲乙醇回收终点温度、精制投料配比的影响,对工艺控制点进行了优化,使产品达到欧洲药典Ph.Eur.7.1的质量要求。  相似文献   
48.
Little theoretical attention has been paid to evidence that Blacks are overrepresented in samples of false confessors compared to Whites. One possible explanation is that innocent Black suspects experience stereotype threat in interrogations and that this threat causes Black suspects to experience more arousal, self-regulatory efforts, and cognitive load compared to White suspects. These psychological mechanisms could lead innocent Black suspects to display more nonverbal behaviors associated with deception and, ironically, increase the likelihood that police investigators perceive them as guilty. In response, investigators might engage in more coercive tactics and exert more pressure to confess on Black suspects than White suspects. This could increase the need to escape interrogation and the likelihood of doing so by confessing falsely more for Blacks than for Whites. I present these hypotheses within a social psychological framework, and discuss future directions for testing the model and theoretical and practical implications of such work. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
49.
Research suggests that threatening information captures attention more rapidly than neutral information. However, in most studies threat stimuli differ perceptually from neutral stimuli and are instrumental to perform the task, leaving the question unanswered whether threat is sufficient to capture attention. In experiment 1, we designed a visual search task with stimuli of equal salience (colored circles) that have the potential to lead to efficient search (10 ms/item). In experiment 2, one of the colors (conditioned stimulus, CS+) was made threatening by means of fear conditioning. Participants responded to a target presented in one of the circles. Overall, the search was faster on congruent trials (where the target was presented in the CS+) than on baseline trials (where the CS + was absent). Furthermore, the search was slower on incongruent trials (where the target was presented in another color than the CS+) than on baseline trials. The search on congruent trials was affected by set size (90 ms/item), but to a lesser extent than on baseline trials (105 ms/item). We conclude that threat prioritizes, but does not capture attention. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
50.
针对目前智能移动机器人在未知环境中学习遇到的如学习主动性、实时性差,无法在线积累学习的知识和经验等问题,受心理学中内部动机的启发,提出一种内部动机驱动的移动机器人未知环境在线自主学习方法,在一定程度上弥补目前该领域存在的一些问题。该方法通过在移动机器人Q学习的框架下,将奖励机制用基于心理学启发的内部动机取代,提高其对于未知环境的学习主动性,同时,采用增量自组织神经网络代替经典Q学习中的查找表,实现输入输出空间的映射,使得机器人能够在线增量地学习未知环境。实验结果表明,通过内部动机驱动的方法,移动机器人对于未知环境的学习主动性得到了提高,智能程度有了明显改进。  相似文献   
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