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991.
In this paper, a novel reconstruction technique based on level set method and algebraic reconstruction technique is proposed for multiphase flow computed tomography (CT) system. The curvature-driven noise reduction method is inserted into the conventional iteration procedure of algebraic reconstruction technique to improve the image quality and convergence speed with limited projection data. By evolving the image as a set of iso-intensity contours after each updation, the sufficient number of iterations for acceptable results is reduced by 80%-90%, while the image quality is enhanced obviously. Quantitative evaluation of image quality is given by using both relative image error and correlation coefficient. The resultant images can be utilized to detect flow regimes for monitoring industrial multiphase flow. Laboratory results demonstrate the feasibility of the proposed method. Phantoms of four typical flow regimes can be reconstructed from few-view projection data efficiently, and the corresponding image errors and correlation coefficients are acceptable for the cases tested in this paper.  相似文献   
992.
Considering the uncertainty of material performance, geometric characteristic and analysis method, the analysis of statistical parameters of the resistance of cast ball-and-socket support joints and the reliability analysis are carried out by JC method (improved first-order second-moment method) based on the relevant experimental data. Results show that the resistance partial factor of the joint increases with the increase of the reliability index. The resistance partial factors are suggested corresponding to the reliability index under different load combinations. Moreover, the suggested resistance partial factor is adopted in reliability design, and it is found that the reliability index of the joint is larger than the target reliability index. The optimal load combination is the one in which live load plays an important control role. Finally, based on the suggested resistance partial factors, the reliability analysis of cast ball-and-socket support joints of a project is conducted.  相似文献   
993.
University policies prohibiting use of mobile devices by medical students during clinical placements are contradicted by regular use by physicians. Consequently, many students use their mobile devices, which can be beneficial for learning but may put patient privacy at risk. This study explores the reasons underlying students' decisions about using mobile devices in clinical settings. We used a mixed-methods sequential explanatory design involving a questionnaire and focus groups. Qualitative data from the questionnaire and focus groups was analysed through thematic analysis. We found students were aware of the risks mobile devices posed to professionalism and medical practice. Despite prohibitions, many made individual decisions to use mobile devices because the benefits outweighed the risks. These students were influenced by an organised, strategic approach to learning and a motivation to comply with the beliefs and behaviours of their medical teams and conform to physicians' directives in order to participate in their community of practice. Many students appear to be transferring everyday use of mobile devices to clinical settings. There is a need to understand and promote aspects of learning that are enhanced by mobile devices in clinical settings, while articulating clear guidelines and boundaries compatible with the professional behaviour expected of students.  相似文献   
994.
This study examined to what extent adolescents’ and their friends’ risk behaviors (i.e., delinquency and alcohol use) hinder or promote their academic achievement (grade point average [GPA]), and vice versa. Longitudinal data were used (= 1,219 seventh- to ninth-grade adolescents; Mage = 13.69). Results showed that risk behaviors negatively affected adolescents’ GPA, whereas GPA protected against engaging in risk behaviors. Moreover, adolescents tended to select friends who have similar behaviors and friends’ behaviors became more similar over time (same-behavior selection and influence). Furthermore, although same-behavior effects seemed to dominate, evidence was found for some cross-behavior selection effects and a tendency in seventh grade for cross-behavior influence effects. Concluding, it is important to investigate the interplay between different behaviors with longitudinal social network analysis.  相似文献   
995.
The current study used a novel methodology based on multivocal ethnography to assess the relations between conformity and evaluations of intelligence and good behavior among Western (U.S.) and non-Western (Ni-Vanuatu) children (6- to 11-year-olds) and adolescents (13- to 17-year-olds; = 256). Previous research has shown that U.S. adults were less likely to endorse high-conformity children as intelligent than Ni-Vanuatu adults. The current data demonstrate that in contrast to prior studies documenting cultural differences between adults' evaluations of conformity, children and adolescents in the United States and Vanuatu have a conformity bias when evaluating peers' intelligence and behavior. Conformity bias for good behavior increases with age. The results have implications for understanding the interplay of conformity bias and trait psychology across cultures and development.  相似文献   
996.
This study utilized actor–partner interdependence modeling to examine the bidirectional effects of younger (Mage = 18 months) and older siblings (Mage = 48 months) on later empathy development in a large (n = 452 families), diverse (42% immigrant) Canadian sample. Controlling for parenting, demographic characteristics, sibling relationship quality, and within-child stability in empathic concern, both younger and older siblings’ observed empathic concern uniquely predicted relative increases in the other's empathy over a period of 18 months. The strength of the partner effects did not differ by birth order. Sex composition moderated the younger sibling partner effect, whereas age gap moderated the older sibling partner effect. This study highlights the important role that siblings play in enhancing the development of care and concern for others.  相似文献   
997.
Two studies investigated 4- to 7-year-olds’ knowledge about pretending. In Study 1, children (N = 66) defined pretending and described examples of own and others’ pretending. In Study 2, children (= 52) defined pretending and then completed a battery of measures that examined their understanding that pretending involved mental states. In Study 1, older children articulated more defining features of pretending than younger children. When describing how they or others pretended, children focused on action or appearance, regardless of whether they had included more defining features in their definitions of pretending. In Study 2, the more defining features children articulated, the better their performance on the battery. We discuss the implications of these data for the role of pretending in children's developing theory of mind.  相似文献   
998.
Eighteen new counselor educators shared in‐depth reports of their efforts to establish an early record of scholarly productivity, critical to their success in academe. Analyses of their experiences using consensual qualitative research methods revealed components of both highly positive and highly discouraging program environments and their impact on participants’ research goals.  相似文献   
999.
Relations between mothers' mind-mindedness (appropriate and nonattuned mind-related comments) at 8 months (= 206), and children's educational attainment at ages 7 (= 158) and 11 (= 156) were investigated in a British sample. Appropriate mind-related comments were positively correlated with reading and mathematics performance at both ages but only in the low-socioeconomic status (SES) group. Path analyses showed that in the low-SES group, appropriate mind-related comments directly predicted age-11 reading performance, with age-4 verbal ability mediating the relation between appropriate mind-related comments and age-7 reading. In contrast, maternal sensitivity and infant–mother attachment security did not predict children's educational attainment. These findings are discussed in terms of genetic and environmental contributions to reading and mathematics performance.  相似文献   
1000.
Although recognized for his wisdom on issues of agriculture, ecology, economics, and theology, writer Wendell Berry has been largely ignored for his thinking on education. Yet the same good sense and clear thinking that he applies to other areas of thought can be seen also in his writings on education. This article reviews what scholars have observed about Berry’s ideas on education, and then contextualizes his thinking through a comparison with two giants of educational theory: John Dewey and Paulo Freire. Berry’s local focus and his emphasis on community and the ecosphere create a vision for education that could lead to a healthier, more peaceable world.  相似文献   
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