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961.
962.
Timothy W. Curby Laura L. Brock Bridget K. Hamre 《Early education and development》2013,24(3):292-309
Research Findings: It is widely acknowledged that consistent, high-quality teacher–student interactions promote optimal developmental outcomes for children. Previous research on the quality of teacher–student interactions provides empirical support for this premise. Little research has been conducted on the consistency of teacher–student interactions. This study examines whether consistency in teachers' emotional support is related to better academic and social outcomes for children. Multiple observations were conducted in 694 prekindergarten classrooms. Mean levels of emotional support and consistency of emotional support were used as predictors in multilevel models. Results indicated that when mean levels of emotional support were controlled, within-day consistency of emotional support predicted several academic outcomes in prekindergarten as well as social competence in kindergarten. Practice or Policy: Results indicate that teachers' consistency of emotional support is a salient aspect of children's classroom environment. Findings suggest that consistency should be considered when evaluating teachers' emotionally supportive interactions. 相似文献
963.
Karen M. La Paro Bridget K. Hamre Jennifer Locasale-Crouch Robert C. Pianta Donna Bryant Dianne Early 《Early education and development》2013,24(4):657-692
Research Findings: Using observational data gathered in 730 kindergarten classrooms in 6 states, the present study focuses on the quality of children's learning opportunities in kindergarten classrooms. Findings show that overall, children experience moderate to low levels of quality in the areas of classroom organization and instructional support in kindergarten. Results are also presented in comparison to children's experiences in the pre-kindergarten year. These comparisons indicate that kindergarten children spend a greater proportion of the school day in language arts, math, and whole-group instruction and less time in centers than they do in pre-kindergarten. An examination of predictors of kindergarten classroom quality indicated that program characteristics (i.e., adult–child ratio, length of school day) and teacher psychological variables (i.e., beliefs and depressive symptoms) were stronger predictors of classroom quality than were teacher experience and educational background. Practice or Policy: Findings are discussed in terms of implications for children's academic and social development in kindergarten as well as for kindergarten teacher preparation and development. 相似文献
964.
965.
In this paper, techniques from the research field of knowledge management are used to improve the maturity of the Computer Based Training (CBT) development process at an IT-oriented organization involved in producing courseware. The project team is facilitated with a knowledge-sharing solution that enables them to unambiguously define their project process, and link templates and best practices to the activities in that process. In addition, a virtual discussion room is provided for them to share new insights. Results from measurement experiments indicate more positive project experiences with projects that used the knowledge-sharing solution. 相似文献
966.
This article provides an international comparative overview of institutional strategies, collaboration patterns and governmental policies related to the use of ICT in higher education. It has been produced as part of an international comparative study on the use of ICT in higher education. A study commissioned by the Dutch Ministry of Economic Affairs and the Ministry of Education, Culture and Science and published as: “The Use of Information and Communication Technology in Higher Education: An International Orientation on Trends and Issues”, B. Collis and M. van der Wende (Eds). University of Twente, CHEPS, 1999. It covers the following range of countries: Belgium, Finland, the United Kingdom, Australia and the United States of America. Additionally some main initiatives at the European level have been taken into account. On the basis of this international comparison, the following main conclusions were drawn. Due in part to the fact that in many cases institutional strategies for ICT are still lacking, interesting experimentation does not generally lead to successful dissemination and adoption on a wider scale. In many cases, the push for a substantial use of ICT in distance learning programs has come from new educati onal markets, life-long learning and international education in particular. The response of higher education to these markets is leading in many countries to a convergence of distance and traditional (on-campus) education. Inter-institutional and inter-sectoral collaboration between universities and companies are characteristics of many successful ICT initiatives, although they do not generally continue into sustainable implementation in the individual institutions. Governments facilitate the use of ICT through the establishment of infrastructure, networks and inter-institutional and public–private partnerships, and try to create the right regulatory environment. Further deregulation will enable institutions to respond to new market demands and will inspire the necessary organizational change in higher education institutions. 相似文献
967.
Agaath M. Dekker-Groen Marieke F. van der Schaaf Karel M. Stokking 《Teachers and Teaching》2013,19(2):150-171
The Teachers of Promise study has followed the work histories of 57 primary and secondary teachers who had been identified at the beginning of their third year of teaching as having the potential to make a significant contribution to the profession. Using data from surveys and interviews, this paper reports on what sustained or inhibited their initial commitment to and enthusiasm for ‘making a difference’, six years later, both in the classroom and in broader school leadership roles. Satisfaction with their day-to-day experiences in their schools was a particularly strong driver of teachers’ career decisions over time. Thirty-four teachers responded to survey items that were used to identify three different groups of teachers: a group of 10 primary school teachers with the highest levels of job satisfaction who were ‘fulfilling their promise’; a group of 21 primary and secondary teachers who were ‘persevering and coping’; and three teachers who were ‘detached and disengaged’. The group with the highest levels of job satisfaction taught in primary schools where they felt respected and valued, and supported to develop their teaching and leadership expertise. School leadership practices and school cultures in the other two groups diminished teachers’ overall job satisfaction and contribution to collective knowledge building in their schools. Almost all of the teachers had retained their commitment to students, to their current schools and to teaching as a career, including those with lower levels of satisfaction. Although these teachers reported ‘collegial’ relationships with their peers, individualistic school cultures, most often in secondary schools, impacted on their opportunities to learn with and from their colleagues. Few secondary school teachers felt appreciated, and included in school decision-making or had found it possible to combine high standards of classroom teaching with management responsibilities. The study indicates that while most promising teachers were still satisfied with teaching after nine years, relatively few were in schools where they were able to make the impact that had been predicted for them early in their careers. 相似文献
968.
Thomas K. Bader Karin de Borst Karin Fackler Thomas Ters Susan Braovac 《Journal of Cultural Heritage》2013,14(5):377-388
Mechanical properties of wood at different length scales of its hierarchical structure are governed by structural and compositional properties on smaller length scales. This opens up the possibility to use microstructural data for estimating mechanical properties, which are difficult to assess by conventional, destructive testing but are nevertheless of high relevance for conservation practice. Herein, we investigate such microstructure-mechanics relationships for a particular example, namely the load bearing archaeological oak of the Oseberg Viking ship, displayed at the Viking Ship Museum in Oslo, Norway. In order to identify the effects of degradation on the mechanical behavior and their relations to the microstructure, recent oak specimens of different geographical origin (Norway and Austria) are investigated as well. Wood exhibits a cellular structure. Its cell walls are composed of an amorphous polymer matrix consisting of lignin and hemicelluloses and embedded, stiff cellulose fibers. At the cell level, experimental studies comprised microscopic investigations of the cellular structure, chemical analyses of the composition of the cell walls, as well as nanoindentation tests on single cell walls. The same samples were also analyzed on the macroscopic level, where additionally mass density and annual ring data were measured together with ultrasonic stiffnesses. The chemical data clearly indicate deterioration in the archaeological oak, affecting mainly hemicelluloses and amorphous cellulose. At the cell wall scale, however, this does not necessarily lead to a weaker material behavior. The nanoindentation modulus, as a measure of the cell wall stiffness, was found to even increase. This is counterintuitive to our understanding of the effects of chemical degradation. It might be due to possible modification of lignin in the Oseberg oak, and thus have a stronger effect on the indentation modulus than the concurrent weakening of the interfaces between the load-carrying cellulose fibers and the connecting cell wall matrix when analyzing wood at the microscopic level. A similar effect is also observed for the transversal stiffness of macroscopic samples, which increases. In tension-dominated loading modes, however, the degradation of the interfaces is the dominant effect, resulting for example in a considerable reduction of the macroscopic stiffness in longitudinal direction. This underlines the utmost relevance of the loading condition on the remaining load-carrying capacity of degraded wood. On the macroscale, effects of the geographical origin (i.e. growth conditions) on ring characteristics of the oak tissues override the effects of degradation on the mechanical behavior. They have to be carefully extracted in order to come up with conclusions on the effect of degradation from macroscopic test results. The identified microstructure-mechanics relationships provide the basis for–in further research steps–building mathematical models describing the relations between microstructural characteristics and macroscopic mechanical properties and, thereon, for structural analyses of historical wooden objects. 相似文献
969.
阐述了配气相位对发动机性能的影响,说明了车用发动机对配气相位的要求及采用可变气门驱动机构的优点.着重介绍了本田公司的可变气门驱动机构VTEC的结构和工作原理. 相似文献
970.
We investigate in the context of crowdsourcing how seekers can increase open innovation performance, measured as received solver attention, by making two strategic decisions: selecting innovation tasks that are well suited for crowdsourcing and choosing between the potentials of status signalling through identity disclosure versus enjoying the benefits of anonymity. Drawing on uncertainty reduction theory, we suggest that a well-articulated problem statement reduces uncertainties of potential solvers and increases their willingness to participate. We argue that the ability of seekers to draft high-quality problem statements depends on the distance between the problem domain and their current knowledge stock. An analysis of 637 crowdsourcing projects finds that problem-seeker knowledge distance and received solver attention are curvilinear related such that moderate levels of knowledge distance maximize solver participation. However, high-status seekers who engage in identity-based status signalling are able to benefit from crowdsourcing across all levels of problem-seeker knowledge distance. 相似文献