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171.
For bulk piezoelectric ceramics plates, the fundamental thickness-stretch (TSt) waves are always coupled to the in-plane extension waves and the symmetric thickness-shear waves. The occurrence of these spurious modes in bulk piezoelectric ceramics plates is undesirable as it may interfere with the operation of transducers. 1–3 piezoelectric composites are promising candidates to suppress the spurious modes mentioned above. However, theoretical modelling of multiphase ceramic composite objects is very complex. In this study, a simple analytical TSt vibration model is constructed from three-dimensional equations of linear piezoelectricity. The mechanical damping is considered in the model by introducing a complex elastic constant. The performance of 1–3 piezoelectric composites is analysed and the electrical impedance results from theoretical and experimental analysis are compared. The results show that there is excellent agreement between the experimental electrical impedance and that obtained by the theoretical TSt vibration analysis. This indicates that 1–3 piezoelectric composites can be operated in a nearly pure TSt vibration mode near the fundamental resonance. The analytical model we present is valid for analysing 1–3 piezoelectric composites plates with large aspect ratios quickly and efficiently. 相似文献
172.
This study addressed why women have greater representation in some STEM (science, technology, engineering, and mathematics) fields compared to others by linking two theoretical approaches, people–thing orientation (PO, TO) and role congruity theory, which emphasizes occupation goal affordances associated with traditionally feminine and masculine roles. Vocational interest and goal affordance ratings (having a positive social impact, family, and occupation status) for occupations characterized as working with people or things were assessed in 1848 students (42% female; 81% white non-Hispanic) majoring in biology (gender balanced), non-biology STEM (male-dominated), and female-dominated health fields. Participant PO and TO interests were also collected. Results indicated that non-biology STEM majors showed lower PO and higher TO interests than biology and health majors. Non-biology STEM majors also endorsed PO and TO interests at similar levels, but the other two major groups indicated higher PO than TO. People Jobs were perceived to more likely afford goals related to family and positive social impact; whereas Thing Jobs were perceived to more likely afford status goals. Interest in People Jobs was similar for women in both STEM major groups. Female non-biology STEM majors were equally interested in People and Thing Jobs; whereas biology majors preferred People Jobs. PO, TO, and goal affordance ratings independently predicted interest in People and Thing Jobs, and gender accounted for very little additional variance. Taken together, the findings point to the importance of using both person–thing orientation and role congruity theory when explaining varied gender representations in different STEM fields. 相似文献
173.
In four samples of adults, individual income was negatively associated with a measure of prefrontal cortex dysfunction even after implementing controls for age, sex, and education. The small association was stronger for men than for women. These results provide support for a neuroeconomic approach to the study of micro-economic variables. 相似文献
174.
A digital access index was associated with measures of national character (such as extraversion and individualism) for 18 industrialized nations, but statistical controls for gross domestic product per capita eliminated these associations. 相似文献
175.
In a replication study, purchasing books online by 137 state college students was predicted by computer/Internet skills. 相似文献
176.
Repeated administration of cognitive tests improves test performance, making it difficult for researchers to gauge the true extent of age-related cognitive decline. The authors examined this issue using data from the Rush Religious Orders Study and linear mixed-effects models. At annual intervals for up to 8 years, more than 800 older Catholic clergy members completed the same set of 19 cognitive tests from which previously established composite measures of cognitive domains were derived. Retest effects on some measures were substantial and continued to accumulate even after 8 annual test readministrations, but effects on other measures were minimal. Across cognitive measures, retest effects were not related to age, sex, or education. Individual differences in retest effects were substantial but not consistent across cognitive measures. The results suggest that retest-based improvement in cognitive test performance can be substantial and persistent. 相似文献
177.
彝族原始宗教和道教都是本土宗教,它们之间有诸多相融、相通之处,如诸神论、祖先崇拜、神仙思想贵阴贵柔、政教合一、返朴归真、天人感应、斋醮、法术法具、禹步等。 相似文献
178.
Atsushi Kimura Jiale Yang Ippeita Dan So Kanazawa 《Journal of experimental child psychology》2010,105(3):256-263
We explored infants’ ability to recognize the canonical colors of daily objects, including two color-specific objects (human face and fruit) and a non-color-specific object (flower), by using a preferential looking technique. A total of 58 infants between 5 and 8 months of age were tested with a stimulus composed of two color pictures of an object placed side by side: a correctly colored picture (e.g., red strawberry) and an inappropriately colored picture (e.g., green-blue strawberry). The results showed that, overall, the 6- to 8-month-olds showed preference for the correctly colored pictures for color-specific objects, whereas they did not show preference for the correctly colored pictures for the non-color-specific object. The 5-month-olds showed no significant preference for the correctly colored pictures for all object conditions. These findings imply that the recognition of canonical color for objects emerges at 6 months of age. 相似文献
179.
The authors compared the associations among perceived maternal socialization goals (self-development, filial piety, and collectivism), perceived maternal parenting styles (authoritative, authoritarian, and training), and the social-emotional adjustment (self-esteem, academic self-efficacy, and depression) between Chinese and European American young adults. The mediation processes in which socialization goals relate to young adults' adjustment outcomes through parenting styles were examined. Results showed that European American participants perceived higher maternal self-development socialization goals, whereas Chinese participants perceived higher maternal collectivism socialization goals as well as more authoritarian parenting. Cross-cultural similarities were found in the associations between perceived maternal authoritative parenting and socioemotional adjustment (e.g., higher self-esteem and higher academic self-efficacy) across the two cultural groups. However, perceived maternal authoritarian and training parenting styles were found only to be related to Chinese participants' adjustment (e.g., higher academic self-efficacy and lower depression). The mediation analyses showed that authoritative parenting significantly mediated the positive associations between the self-development and collectivism goal and socioemotional adjustment for both cultural groups. Additionally, training parenting significantly mediated the positive association between the filial piety goal and young adults' academic self-efficacy for the Chinese group only. Findings of this study highlight the importance of examining parental socialization goals in cross-cultural parenting research. 相似文献
180.
Facial electromyography (EMG) is a useful physiological measure for detecting subtle affective changes in real time. A time
series of EMG data contains bursts of electrical activity that increase in magnitude when the pertinent facial muscles are
activated. Whereas previous methods for detecting EMG activation are often based on deterministic or externally imposed thresholds,
we used regime-switching models to probabilistically classify each individual’s time series into latent “regimes” characterized
by similar error variance and dynamic patterns. We also allowed the association between EMG signals and self-reported affect
ratings to vary between regimes and found that the relationship between these two markers did in fact vary over time. The
potential utility of using regime-switching models to detect activation patterns in EMG data and to summarize the temporal
characteristics of EMG activities is discussed. 相似文献