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201.
Marcel?B.?M.?de?CroockEmail author Fred?Paas Henrik?Schlandbusch Jeroen?J.?G.?van?Merri?nboer 《Educational technology research and development : ETR & D》2002,50(4):47-58
This article describes a set of computerized tools that support the design and evaluation of competency-based training programs. The training of complex skills such as air traffic control and process control requires a competency-based approach that focuses on the integration and coordination of constituent skills and transfer of learning. At the heart of the training are authentic whole-task practice situations. The instructional design tools are based on van Merriënboer's 4C/ID* methodology (1997). The article describes a training design tool (Core) that supports the analysis and design for competency-based training programs and an evaluation tool (Eval) that supports the subsequent revision of this training design. 相似文献
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There are striking gaps between Roma and non-Roma higher education (HE) participation rates, with less than 1% of Roma possessing a tertiary-level qualification [United Nations Development Programme, World Bank and European Commission. 2011a. “The Situation of Roma in 11 EU Member States.” Accessed 3 April 2015. http://issuu.com/undp_in_europe_cis/docs/_roma_at_a_glance_web/1#download]. As the Decade of Roma Inclusion (2005–2015) closes, this renders the present a salient moment to reflect on Roma students’ HE experiences. Widening educational access for marginalised groups raises specific questions about where responsibility for doing so lies – with tensions between individualised articulations of raising aspiration and notions of collective responsibility framed in a social justice agenda. Drawing on interviews with five Roma women students, this paper unpacks the contradictions between desiring access to HE for individual self-betterment and concurrent pulls towards educating for the wider benefit of ‘improving’ Roma communities. Using Ahmed’s [2012. On Being Included: Racism and Diversity in Institutional Life. Durham, North Carolina: Duke University Press] work on institutional belonging, we explore the specifically gendered nature of these narratives in how ‘doubly’ marginalised bodies are positioned as outsiders, in receipt of an educational gift. 相似文献
206.
Wojciech Szczęsny Magdalena Kuligowska-Prusińska Stanisław Dąbrowiecki Jakub Szmytkowski Adrian Reśliński Maciej Słupski 《Journal of Zhejiang University. Science. B》2018,19(1):65-70
Purpose
Metalloproteinases are a key component of the pathogenesis of abdominal hernias. Obesity is considered a risk factor in herniogenesis and hernia recurrence. The aim of this study was to evaluate the serum concentrations of metalloproteinase-2 (MMP-2), MMP-9, MMP-13, and adiponectin in morbidly obese and nonoverweight controls.Materials and methods
The participants were recruited from among patients undergoing bariatric and non-bariatric surgery and divided into two groups: I (body mass index (BMI)≥35 kg/m2, n=40) and II (BMI<25 kg/m2, n=30). Serum concentrations of MMP-2, MMP-9, MMP-13, and adiponectin were measured using enzyme-linked immunosorbent assay (ELISA).Results
A statistically significant difference between groups was observed for MMP-2 concentration. The median MMP-9 concentration was higher in the obese group, but the difference was not statistically significant. Median MMP-13 concentrations did not differ between groups. Serum adiponectin concentration was insignificantly higher in the non-obese group.Conclusions
The elevated serum MMP-2 and MMP-9 concentrations in obese individuals may be related to the higher incidence of incisional hernias in this population.207.
Visual cues have an important role in food preference for both rats and humans. Here, we aim to isolate the effects of numerosity, density, and surface area on food preference and running speed in rats, by using a forced-choice maze paradigm. In Experiment 1, rats preferred and ran faster for a group of multiple smaller pellets rather than a single large pellet, corroborating previous research (Capaldi, Miller, & Alptekin Journal of Experimental Psychology: Animal Behavior Processes, 15(1), 75–80, 1989). Further experiments tested the prevailing hypothesis that multiple food pieces are more reinforcing because they occupy a larger surface area. Experiment 2 controlled for numerosity by utilizing a continuous food: mashed potatoes flattened to cover a larger surface area or rounded into a ball. The rats preferred and ran faster for the flattened potatoes, suggesting surface area plays a role in quantity estimations. Finally, in Experiment 3, rats displayed no preference or difference in running speed between a group of scattered and clustered pellets when number of pellets were kept constant. Taken together, these results suggest that density has an important role in food perception—that is, the rewarding effect of higher numerosity or larger surface area is removed when the food does not fill out the entire space. Alternative explanations and implications for human diet are discussed. 相似文献
208.
韩礼德系统语法语言分析的模式 总被引:3,自引:0,他引:3
:语言可以从不同角度加以研究。该文从六个方面简单阐述了系统语法大师M .A .K .Halliday语言分析的模式 ,主要内容包括 :语言的层次 ,链轴和选择轴 ,语法结构 ,语法单位 ,语法的级阶和语法系统 相似文献
209.
Carrie D. Allen 《学习科学杂志》2017,26(3):407-436
In this article, we investigate how the national imperative to increase opportunities for young women of color in science, technology, engineering, and mathematics (STEM) and to broaden their participation was taken up locally at two high schools in one school district. Using ethnographic and longitudinal data, we focus on four young women of color (two at each school) as they negotiated STEM-related identities in the discursive and practice contexts of their lives at school. Using Holland and Lave’s concept of history in person, we view the young women as fighting for particular versions of a future self while entangled in discursive and social relations that threatened to position them differently than they wished to be. We find that their fight for future selves was not—for them—with the national narrative about women of color in STEM but with local school narratives that negatively positioned students of color more broadly and remained silent on issues of gender, the intersection of gender and race, and the implications for STEM. High school success in STEM came as a hopeful but potentially fragile byproduct of struggles to differentiate themselves from people like them (other Blacks, Latinas, the poor). Implications of these findings are discussed. 相似文献
210.
This paper presents an adaptive strategy for controlling chaotic systems. By employing the phase space reconstruction technique in nonlinear dynamical systems theory, the proposed strategy transforms the nonlinear system into canonical form, and employs a nonlinear observer to estimate the uncertainties and disturbances of the nonlinear system, and then establishes a state-error-like feedback law. The developed control scheme allows chaos control in spite of modeling errors and parametric variations. The effectiveness of the proposed approach has been demonstrated through its applications to two well-known chaotic systems: Duffing oscillator and Rössler chaos. 相似文献