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91.
One-dimensional silicon nanowires have been grown by thermal evaporation and their growth orientations determined by transmission electron microscopy studies. The nanowires, which are often highly curved in morphology and heavily twinned in microstructure, are crystallographically separated into several sections, each with a characteristic crystallographic orientation along the wire axis. Straight nanowires, or straight sections in a curved nanowire, are found to have non-unique crystallographic orientations when {111} twinning occurs. 相似文献
92.
Tae Wook Heo Yi Wang Saswata Bhattacharya Xin Sun Shenyang Hu Long-Qing Chen 《Philosophical Magazine Letters》2013,93(2):110-121
We propose a phase-field model for modeling microstructure evolution during deformation twinning. The order parameters are proportional to the shear strains defined in terms of twin plane orientations and twinning directions. Using a face-centered cubic Al as an example, the deformation energy as a function of shear strain is obtained using first-principle calculations. The gradient energy coefficients are fitted to the twin boundary energies along the twinning planes and to the dislocation core energies along the directions that are perpendicular to the twinning planes. The elastic strain energy of a twinned structure is included using the Khachaturyan's elastic theory. We simulated the twinning process and microstructure evolution under a number of fixed deformations and predicted the twinning plane orientations and microstructures. 相似文献
93.
Małgorzata Kossowska Yoram Bar‐Tal 《British journal of psychology (London, England : 1953)》2013,104(4):457-480
In contrast to the ample research that shows a positive relationship between the need for closure (NFC) and heuristic information processing, this research examines the hypothesis that this relationship is moderated by the ability to achieve closure (AAC), that is, the ability to use information‐processing strategies consistent with the level of NFC. Three different operationalizations of heuristic information processing were used: recall of information consistent with the impression (Study 1); pre‐decisional information search (Study 2); and stereotypic impression formation (Study 3). The results of the studies showed that there were positive relationships between NFC and heuristic information processing when participants assessed themselves as being able to use cognitive strategies consistent with their level of NFC (high AAC). For individuals with low AAC, the relationships were negative. Our data show that motivation–cognition interactions influence the information‐processing style. 相似文献
94.
Maël Lemoine 《Theoretical medicine and bioethics》2013,34(4):309-325
Conceptual analysis of health and disease is portrayed as consisting in the confrontation of a set of criteria—a “definition”—with a set of cases, called instances of either “health” or “disease.” Apart from logical counter-arguments, there is no other way to refute an opponent’s definition than by providing counter-cases. As resorting to intensional stipulation (stipulation of meaning) is not forbidden, several contenders can therefore be deemed to have succeeded. This implies that conceptual analysis alone is not likely to decide between naturalism and normativism. An alternative to this approach would be to examine whether the concept of disease can be naturalized. 相似文献
95.
探讨个人幸福指数-中小学生版(PWI-SC)在中国的适用性以及中澳两国中学生个人幸福指数的跨文化差异。采用PWI-SC施测522名中国中学生、185名澳洲中学生,进行区分度、信度和效度检验,发现该问卷可运用于中国中学生个人幸福指数的调查,个别项目需稍加修改。比较中澳中学生的施测结果,中国中学生的个人幸福指数低于澳洲中学生,中国中学生得分为47-70,澳洲中学生得分为51-72;中国中学生除在个人已有成就项目上得分高于澳洲中学生外,其他方面均较低;中澳两国初中生的个人幸福指数均显著高于高中生,两国初高中生个人幸福指数的差异体现在不同方面;中澳两国中学生个人幸福指数的年龄差异均显著,进一步事后分析发现,两国中学生个人幸福指数的基本趋势均为随年龄增长,个人幸福指数降低,中国15岁中学生的个人幸福指数较高。PWI-SC基本适用于中国中学生;中学生随年龄增长,个人幸福指数降低;中国中学生的个人幸福指数低于澳洲中学生。 相似文献
96.
本文从博弈的角度分析了意外考试悖论,指出了以往解决方案的不足,给出了一种新的方案。根据这个新方案,考试悖论的推理中使用了倒推法和弱下策反复剔除法。本文接着讨论了这些博弈推理方法的不足。然后把这个新的博弈方案用到卡片悖论和方格悖论这些考试悖论的变种里。最后指出,在考试悖论里,比起倒推法,弱下策剔除法是引起悖论的更根本的原因。 相似文献
97.
Colin Camerer Yi Xin Clarice Zhao 《Journal of the experimental analysis of behavior》2024,121(1):108-122
This article applies a two-process “neural autopilot” model to field data. The autopilot model hypothesizes that habitual choice occurs when the reward from a behavior has low numerical “doubt” (i.e., reward prediction errors are small). The model toggles between repeating a previous choice (habit) when doubt is low and making a goal-directed choice when doubt is high. The model has ingredients established in animal learning and cognitive neuroscience and is simple enough to make nonobvious predictions. In two empirical applications, we fit the model to field data on purchases of canned tuna and posting on the Chinese social media site Weibo. This style of modeling is called “structural” because there is a theoretical model of how different variables influence choices by agents (the “structure”), which tightly restricts how hidden variables lead to observed choices. There is empirical support for the model, more strongly for tuna purchases than for Weibo posting, relative to a baseline “reduced-form” model in which current choices are correlated with past choices without a mechanistic (structural) explanation. An interesting set of predictions can also be derived about how consumers react to different kinds of changes in prices and qualities of goods (this is called “counterfactual analysis”). 相似文献
98.
Employees' innovative work behavior (IWB) is one of the key factors in improving organizational competitiveness. Previous studies show that challenge and hindrance stress can impact employees' IWB, but our understanding of the exact mechanism underlying the impact is still limited. The present study employed four scales (Challenge and Hindrance Stress Scale, Thriving at Work Scale, Chinese Emotional Exhaustion Scale, and Employee Innovative Behavior Scale) to collect questionnaire data from 789 employees in diverse organizations via an online platform. A two-path mediation model was constructed. The results show that: (a) challenge stress positively predicted thriving at work and IWB; (b) thriving at work played a partial mediation effect between challenge stress and IWB; (c) hindrance stress negatively predicted thriving at work and positively predicted emotional exhaustion; and (4) hindrance stress did not directly impact IWB while thriving at work and emotional exhaustion were main mediators in the relationship between hindrance stress and IWB. These findings suggest that employees should sensibly cope with different work stresses, while managers should plan work tasks scientifically and give employees adequate opportunities to learn and rest in order to keep them in a positive state to solve problems and work creatively. 相似文献
99.
100.
本研究中运用了两个实验探讨数数干预和测查条件对儿童在集合比较中运用数数的影响。干预对3岁儿童(M=3:9)没有影响。在平均年龄为4岁4个月时.干预组儿童比控制组儿童更倾向于用数数比较集合.自然组儿童也比传统组更倾向于用数数。许多4岁儿童在无干预时不用数数可能是因为,1)不知数数比视觉性比较更有效,或2)他们在集合比较中的数数极易受测查情景因素的影响。儿童在集合比较中的数数运用与他们的数数水平密切关联。 相似文献