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931.
Sylvia Rojas‐Drummond Nancy Mazón Karen Littleton Maricela Vélez 《Journal of Research in Reading》2014,37(2):138-158
The present study explores the development and promotion of reading comprehension in primary school students, in the context of the implementation of an educational programme called ‘Learning Together’ (LT). The programme, which centred on collaborative learning activities, was designed to promote oral and written communication in primary school Mexican children. Analyses revealed that children who participated in the LT programme, in comparison with students in a control condition, produced higher‐quality written summaries of texts they had read, both when working in teams and when working individually. This suggests that the LT participants appropriated and transferred the text comprehension strategies promoted, so that they could apply these strategies effectively not only in collaborative contexts but also independently, that is, in a self‐regulated and autonomous fashion. The theoretical and practical implications of the work are discussed in relation to understanding and promoting oracy and literacy processes in primary school students. 相似文献
932.
The myth of home is what distinguishes children??s literature from adult novels (Wolf 1990). Nodelman and Reimer (The Pleasures of Children??s Literature, 2003) write that while ??the home/away/home pattern is the most common story line in children??s literature, adult fiction that deals with young people who leave home usually ends with the child choosing to stay away?? (pp. 197?C198). In a critical content analysis of recent award-winning middle reader novels from the United States, the United Kingdom, and Australia, a new pattern was observed. This pattern, called a postmodern metaplot, begins with the child being abandoned, rather than the child leaving the home. The child??s journey is to construct a home within a postmodern milieu complete with competing truths and failed adults. Ultimately, the child??s postmodern journey ends with very modern ideal of the child leading the adults to a hopeful ending, a home. The article explores the changing roles of childhood and adulthood in children??s literature and questions if the mythology of home can be undone. 相似文献
933.
C. G. Olesen B. H. Larsen E. L. Andresen M. de Zee 《European Journal of Sport Science》2015,15(3):242-247
AbstractThe aim of this study was to develop a performance test set-up for America's Cup grinders. The test set-up had to mimic the on-boat grinding activity and be capable of collecting data for analysis and evaluation of grinding performance. This study included a literature-based analysis of grinding demands and a test protocol developed to accommodate the necessary physiological loads. This study resulted in a test protocol consisting of 10 intervals of 20 revolutions each interspersed with active resting periods of 50 s. The 20 revolutions are a combination of both forward and backward grinding and an exponentially rising resistance. A custom-made grinding ergometer was developed with computer-controlled resistance and capable of collecting data during the test. The data collected can be used to find measures of grinding performance such as peak power, time to complete and the decline in repeated grinding performance. 相似文献
934.
Katemari Rosa 《Cultural Studies of Science Education》2018,13(4):1005-1013
This forum paper dialogues with Sheron Mark’s A bit of both science and economics: a non-traditional STEM identity narrative. In her paper, she discusses the development of a Science, Technology, Engineering, and Mathematics (STEM) identity by a young African American male during an informal STEM for Social Justice Program. Here, the discussion focuses on Black masculinities, identity formation, and the role of science educators in making STEM fields a welcoming place for young Black men. Drawing from Mark’s data and discussion, this paper is a dialogue between science identity possibilities in the United States and in Brazil when we look at the intersections of race, gender, and socioeconomic status. Using the shared colonial past of both countries a connection is established to address race relations within science education. The main argument in this paper is that racism can no longer be denied and dismissed by the science education community worldwide and that intersectional approaches are needed to face this issue. 相似文献
935.
Research in non-equalization machining method for spatial cam 总被引:1,自引:0,他引:1
Many kinds of devices with cam have been widely used in various mechanical equipments. However, non-equalization machining for spatial cam trough remains to be a difficult problem. This paper focuses on the analysis of running conditions and machining processes of spatial cam with oscillating follower. We point out the common errors in the biased distance cutting. By analyzing the motion of oscillating follower of spatial cam, we present a new 3D curve expansion model of spatial cam trough-outline. Based on this model, we have proposed a machining method for trochoidal milling with non-equalization diameter cutter. This new method has led to a creative and effective way for non-equalization diameter machining for spatial cam with oscillating follower. 相似文献
936.
937.
Robert B. Anderson Julius A. Marshall Andrea L’Afflitto 《Journal of The Franklin Institute》2021,358(12):6281-6308
In classical model reference adaptive control (MRAC), the adaptive rates must be tuned to meet multiple competing objectives. Large adaptive rates guarantee rapid convergence of the trajectory tracking error to zero. However, large adaptive rates may also induce saturation of the actuators and excessive overshoots of the closed-loop system’s trajectory tracking error. Conversely, low adaptive rates may produce unsatisfactory trajectory tracking performances. To overcome these limitations, in the classical MRAC framework, the adaptive rates must be tuned through an iterative process. Alternative approaches require to modify the plant’s reference model or the reference command input. This paper presents the first MRAC laws for nonlinear dynamical systems affected by matched and parametric uncertainties that constrain both the closed-loop system’s trajectory tracking error and the control input at all times within user-defined bounds, and enforce a user-defined rate of convergence on the trajectory tracking error. By applying the proposed MRAC laws, the adaptive rates can be set arbitrarily large and both the plant’s reference model and the reference command input can be chosen arbitrarily. The user-defined rate of convergence of the closed-loop plant’s trajectory is enforced by introducing a user-defined auxiliary reference model, which converges to the trajectory tracking error obtained by applying the classical MRAC laws before its transient dynamics has decayed, and steering the trajectory tracking error to the auxiliary reference model at a rate of convergence that is higher than the rate of convergence of the plant’s reference model. The ability of the proposed MRAC laws to prescribe the performance of the closed-loop system’s trajectory tracking error and control input is guaranteed by barrier Lyapunov functions. Numerical simulations illustrate both the applicability of our theoretical results and their effectiveness compared to other techniques such as prescribed performance control, which allows to constrain both the rate of convergence and the maximum overshoot on the trajectory tracking error of uncertain systems. 相似文献
938.
Failure Modes and Effects Analysis (FMEA) is a proactive assessment tool originally created for quality assurance in manufacturing industries. FMEA involves the assignment of rankings for frequency, severity, and detection of errors within a process. Catalogers at ProQuest undertook an innovative project to use FMEA to evaluate MARC record production. This article provides an overview of FMEA for process evaluation and summarizes an application for cataloging. It considers the tool's value for error-proofing in MARC record creation and how FMEA might be applied more effectively in a variable environment. 相似文献
939.
940.
Peer collaboration is a pedagogical method currently used to facilitate learning in classrooms. Similarly, computer-learning environments (CLEs) are often used to promote student learning in science classrooms, in particular. However, students often have difficulty utilizing these environments effectively. Does peer collaboration help students learn with these environments? Little research looking closely at face-to-face peer collaboration with computer learning environments exists. Utilizing a social-cognitive theoretical framework, this study investigated the relation between the conceptual-knowledge learning and the collaborative regulatory behaviors of students working with a peer as they studied about the human circulatory system using a hypermedia CLE. Fifty-four high-school students from the East Coast of the United States were audiotaped to identify the collaborative regulatory behaviors they evidenced as they studied. Results revealed significant correlations among students’ proportion of categories of regulatory behaviors and their learning gains (from pretest to posttest). Moreover, qualitative analyses revealed particular behaviors that larger-gain collaborative pairs engaged in to a greater extent than smaller-gain pairs as they learned with the hypermedia environment. 相似文献