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61.
This paper studies changes of standard errors (SE) of the normal-distribution-based maximum likelihood estimates (MLE) for confirmatory factor models as model parameters vary. Using logical analysis, simplified formulas and numerical verification, monotonic relationships between SEs and factor loadings as well as unique variances are found. Conditions under which monotonic relationships do not exist are also identified. Such functional relationships allow researchers to better understand the problem when significant factor loading estimates are expected but not obtained, and vice versa. What will affect the likelihood for Heywood cases (negative unique variance estimates) is also explicit through these relationships. Empirical findings in the literature are discussed using the obtained results.  相似文献   
62.
多体素模式分析(multi-voxel pattern analysis,MVPA)是一种基于机器学习理论发展出来的新的功能磁共振数据分析技术。MVPA技术通过训练分类器,对由不同认知状态引起的多体素信号模式进行分类。与传统的基于单个体素的分析方法相比,该技术可更敏感地检测脑对认知状态的表征,并使得从神经信号解码认知状态成为可能。文章介绍MVPA技术的基本原理、分析步骤以及可以用MVPA来解决的科学问题,并对应用中可能面临的问题提供了参考建议。  相似文献   
63.
The length of the stagnant stage during the new ferrite growth starting from a mixture of austenite and ferrite has been investigated for a Fe-0.17Mn-0.023C (wt%) alloy. It was found that the stagnant stage depends on the thermal path followed to create the mixture, and deduce that the tie-lines for austenite to ferrite transformation are quite different from those for ferrite to austenite transformation. The length of the stagnant stage is determined by the very local partitioning effect at the interface, and it can be used as a tool to monitor the Mn partitioning.  相似文献   
64.
Cellular precipitation (also known as discontinuous precipitation) has been observed at the grain boundaries of a newly developed nickel-based Inconel740H alloy designed for use at 700?°C in advanced ultrasupercritical coal-fired power plants. By means of element mapping and selected area diffraction, the cellular precipitates were identified as Cr-rich M23C6 carbides. The onset of cellular precipitation was found to follow a pucker mechanism in Inconel740H. The cellular precipitates at the grain boundaries, even at low volume fractions, were severely detrimental to the creep strength at 750?°C. The creep rupture life of Inconel740H containing cellular precipitates at grain boundaries was only one-tenth of that for the alloy without cellular precipitates. The reason for the drastically decreased creep rupture life is attributed to the poor resistance of cellular precipitates to crack propagation during creep.  相似文献   
65.
The main purpose of this study is to investigate the mechanisms through which recruiters' positive moods lead to organizational attraction. Participants consisted of 161 applicant–recruiter dyads from 55 companies in Taiwan. Results show that recruiters' felt positive moods were positively related to applicant's perceptions of informativeness and competence, which, in turn, influenced organizational attraction. In addition, recruiters felt that positive moods were positively related to their display of positive moods, which were positively related to applicant's positive moods, which, in turn, affected organizational attraction.  相似文献   
66.
现代肿瘤的诊疗水平已经有了长足的进步,先进的诊断技术使得很多肿瘤得以早期发现并积极治疗,很多晚期患者也不再面临无药可用的境地,但由于临床医生的认识存在偏差,存在过度诊断和过度治疗的问题,进而给患者带来不必要的负担和痛苦。美国临床肿瘤学会(ASC0)年会上发布了一篇名为“ASCO为改善肿瘤治疗质量及医疗花费的5项建议”的文章,特别提出要重视五项临床广泛应用、花费较大,但缺乏高级临床证据的肿瘤治疗或干预措施,也提示我们需要充分评估,综合思考,为合适的患者提供正确的诊治方案,才能给患者带来更大的获益。  相似文献   
67.
Sketching is widely used in design to generate creative ideas. Design studies present stimuli during sketching to enhance creativity. This study examines the effect of stimuli presented during different sketching states, especially of those presented during the stuck period. It conducted a sketching experiment that enrolled 41 students with an average of 5.7 years’ practice in industrial design. The sketching with stimuli presented at regular intervals, those with stimuli presented during the stuck period, and those without stimulus were compared. Eye movements during the sketching processes were recorded. The attention to stimuli, and the direct applications of stimuli to design ideas, and the idea connection and idea differentiation were analyzed. Participants sketching with stimuli presented during the stuck period had a higher sketching quality, compared with those in other experimental conditions. They fixated longer on stimuli, built more links among related ideas, and had a more differentiated and balanced exploration. This study then proposed the mechanisms of stimuli processing. The stimuli presented at regular intervals were stored and acted as additional memory. The stimuli presented during the stuck period were dissected and acted as supporter, inducing a more creative sketching.  相似文献   
68.
Most impulse purchasing research investigates individual‐level factors. This paper, however, examines the influence of shopping companion gender on impulse purchasing. The results of the three studies show that shoppers were more likely to exhibit impulse purchase behavior when shopping with an opposite gender companion. In addition, shoppers who were in the low‐cohesive condition and who shopped with an opposite gender companion were more likely to exhibit impulse purchase behavior than those who shopped with the same gender companion, and those who were susceptible to interpersonal influence were also more likely to exhibit impulse purchase behavior when shopping with an opposite gender companion. For shoppers who were not as susceptible to interpersonal influence, the influence of their companion's gender appeared to diminish on impulsive purchasing.  相似文献   
69.
The purpose of this study is to discuss the dynamic interdependence of knowledge and economic growth. We show that the traditional economics, which treats knowledge as parameters and is mainly developed within linearized, stable and static frameworks can hardly explain the modern economic complexity. We argue that it is necessary to treat creativity, learning and knowledge utilization as endogenous dynamic processes of social and economic evolution. To handle with the complicated dynamic interdependence of wealth and knowledge accumulation, we need to apply genuine nonlinear dynamic theory. In particular, we discuss possible benefits of government's intervention in education and science to the society when the social and economic evolution is characterized of nonlinearity, instability and multi‐equilibria.  相似文献   
70.
ABSTRACT

Using faces as the priming stimuli, the present study explored the influence of facial expressions on the activation of gender stereotypes using a lexical decision paradigm. Experiment 1 explored the activation of gender stereotypes when the facial primes contained only gender information. The results showed that gender stereotypes were activated. In Experiment 2, the facial primes contained both gender category and expression information. The results indicated that gender stereotypes were not activated. Experiment 3 required the participants to make emotion, gender, or impression decisions concerning the facial primes before the lexical decision task. The results showed that gender stereotypes were not activated in emotion and impression decisions conditions, whereas stereotypes were activated in gender decisions condition. These finding suggest that facial expressions can inhibit automatic activation of gender stereotypes, unless the perceivers perform gender categorization processing to prime faces intentionally.  相似文献   
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