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991.
Erin M. West Lynne Guillot Miller Randall M. Moate 《Early Childhood Education Journal》2017,45(3):379-391
This phenomenological study explored six single mothers’ experiences of support at their young children’s school. Themes resulting from interpretative phenomenological analysis suggest the single mothers experienced tangible (e.g., school resources, school-wide events, structural flexibility, teachers’ formal communication) and intangible (e.g., caring relationships with school faculty and staff, experiencing teachers as parenting partners, perceiving acceptance from the school environment) forms of support from their children’s school. Furthermore, results suggest these single mothers experienced intangible supports more prominently than tangible forms of support. The support needs of these single mothers at their young children’s school were also explored including the mothers’ desire for stronger relationships with other parents and families at the school. 相似文献
992.
Classroom data modeling involves posing questions, identifying attributes of phenomena, measuring and structuring these attributes, and then composing, revising, and communicating the outcomes. Selecting attributes is a fundamental component of data modeling, and the considerations made when selecting attributes is the focus of this paper. A teaching experiment involving 2 teacher educators and 25 pre-service teachers (PSTs) was carried out with 24 young children (5–6-year-olds) as part of a 4-day data modeling investigation. Although perceptual features of the data influenced initial approaches to attribute selection, considerations of the problem situation influenced a shift from the perceptual and towards consideration of attributes such as taxonomy, habitat, behavior, and diet. Expertise in the data context (animal kingdom) and ability to collaborate and negotiate within groups supported children in their ability to switch attributes, attend to multiple situations presented by the problem, and modify and extend their categorizations of data. 相似文献
993.
We used an appetitive sensory preconditioning procedure to investigate temporal integration in rats in two experiments. In Phase 1, rats were presented with simultaneous compound trials on which a 10-sec conditioned stimulus (CS) X was embedded within a 60-sec CS A. In Group Early, CS X occurred during the early portion of CS A, whereas in Group Late, CS X occurred during the latter portion of CS A. In Phase 2, CS X was paired simultaneously with sucrose. On a subsequent test with CS A, the rate of magazine entries peaked during the early portions of the stimulus in Group Early and during the latter portions of the stimulus in Group Late (Experiments 1 and 2). Similar response peaks were not observed on tests with a control stimulus that had been presented in compound with a stimulus that did not signal reward (Experiment 2). 相似文献
994.
P. C. Deshmukh Parth Rajauria Abiya Rajans B. R. Vyshakh Sudipta Dutta 《Resonance》2017,22(9):847-866
The brachistochrone problem posed by Bernoulli and its solution highlights one of the most famous experiments in physics which illustrates the variational principle. This pedagogical study is designed to ignite a classroom discussion on the variational problem. We overview the Euler–Lagrange formalism of the variational principle and obtain the solution to the brachistochrone problem. We demonstrate the success of the variational method using brachistochrone models which were fabricated specially for this purpose. 相似文献
995.
Tobias H. Stark Lars Leszczensky Sebastian Pink 《Zeitschrift für Erziehungswissenschaft》2017,20(3):475-498
Research has established that adolescents both befriend peers based on their academic achievement and adjust their own achievement to that of their friends’ over time. However, these processes may be different for ethnic minority students, because some of them may adhere to an oppositional culture that rejects striving for academic success. We examine respective differences between self-identified ethnic minority and majority students using longitudinal social network analysis (stochastic actor-oriented models) in a sample of 1175 students (aged 13) from 12 grade-level networks in Germany secondary schools. Among the students, we find that academically successful students in particular prefer friends with high grades, but that students with poor grades exert more social influence on their friends to adjust their performance. Moreover, while minority students are indeed less inclined to select friends with higher grades, both ethnic majority and minority youth prefer friends with similar academic achievement and are similarly influenced by their friends’ achievement. However, social influence is stronger from same-ethnic than from inter-ethnic friends. In sum, there is mixed evidence for an oppositional culture among ethnic minority students in our sample. 相似文献
996.
997.
提出了一种基于位置敏感哈希算法的海量文本数据查询算法,通过位置敏感哈希算法将文本数据的特征向量映射到哈希桶中,从而有效地降低了计算复杂度并提高了数据检索的效率。首先,利用TF-IDF特征表示文本的特征向量,并根据给定的哈希函数集把文本的特征向量映射至哈希桶;接下来,利用哈希表为给定的文本计算出与之对应的直方图,通过直方图距离计算文本的相似度;最后,通过计算目标文本集中的文本与待查询文本的相似度进行文本排序,排序分值高的文本作为相关文本返回给用户。实验结果表明,对比已有方法文本提出的算法在MAP以及查全率-查准率曲线两个测度上都获得了较好的性能。 相似文献
998.
Shuangshuang Tan Yalong Jiang Shuyan Ni Hao Wang Fangyu Xiong Lianmeng Cui Xuelei Pan Chen Tang Yaoguang Rong Qinyou An Liqiang Mai 《国家科学评论(英文版)》2022,9(11)
The uncontrollable formation of Li dendrites has become the biggest obstacle to the practical application of Li-metal anodes in high-energy rechargeable Li batteries. Herein, a unique LiF interlayer woven by millimeter-level, single-crystal and serrated LiF nanofibers (NFs) was designed to enable dendrite-free and highly efficient Li-metal deposition. This high-conductivity LiF interlayer can increase the Li+ transference number and induce the formation of ‘LiF–NFs-rich’ solid–electrolyte interface (SEI). In the ‘LiF–NFs-rich’ SEI, the ultra-long LiF nanofibers provide a continuously interfacial Li+ transport path. Moreover, the formed Li–LiF interface between Li-metal and SEI film renders low Li nucleation and high Li+ migration energy barriers, leading to uniform Li plating and stripping processes. As a result, steady charge–discharge in a Li//Li symmetrical cell for 1600 h under 4 mAh cm−2 and 400 stable cycles under a high area capacity of 5.65 mAh cm−2 in a high-loading Li//rGO–S cell at 17.9 mA cm−2 could be achieved. The free-standing LiF–NFs interlayer exhibits superior advantages for commercial Li batteries and displays significant potential for expanding the applications in solid Li batteries. 相似文献
999.
Ohne Zusammenfassung 相似文献
1000.
M. Mercedes Martínez-González Gérald Duffing 《Education and Information Technologies》2007,12(4):211-228
The Convergence process in which European Union (EU) universities are at present involved supposes that these institutions not only have to re-structure their degree programmes, but also their teaching and learning methodologies. We study the impact of this EU process on Database teaching, comparing the practices of three different European universities and using the Convergence goals as criteria. In our discussion, we identify which aspects in each university are closer to the Convergence goals, and which are likely to help in achieving these goals. 相似文献