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991.
In order to predict and improve the performance of natural gas/diesel dual fuel engine (DFE), a combustion rate model based on forward neural network was built to study the combustion process of the DFE. The effect of the operating parameters on combustion rate was also studied by means of this model. The study showed that the predicted results were good agreement with the experimental data. It was proved that the developed combustion rate model could be used to successfully predict and optimize the combustion process of dual fuel engine. Project supported by National Lab. for Automotive Engine and Safety, Tsinghua University, China  相似文献   
992.
993.
Four ethnically diverse faculty members in the field of education discuss the professional impact and personal affects of introducing critical themes of race, class, gender, and culture within their research and course offerings. Given that the professional outlook for university faculty of color in general, is grim, a willingness to imbue their research and courses with a critical interrogation of prevailing education topics and theories would seem to invite greater personal risk and professional jeopardy. The following dialogue introduces both the mechanisms by which critical faculty in general, and faculty of color in particular, can be conditioned to subordinate their critical impulses and the strategies they use to resist academic cultures of domestication.  相似文献   
994.
At school, pupils often cooperate on common projects and must coordinate their different individual actions. However, grades are pervasively used even in cooperative situations, which make the pupils’ differences in achievement and their relative rank salient and may reduce their inclination to work constructively with others. Thus, we hypothesized that grades would elicit disruptive interactions and reduce performance in a cooperative cognitive-motor task necessitating inter-individual coordination of members. In a study with 5th graders, grades (vs. a neutral concept) were primed at the onset of a cooperative group interaction. Results showed that, although pupils were set to work cooperatively, priming grades (vs. neutral concepts) harmed inter-individual coordination by eliciting more negative dominant behaviours among pupils during interactions, which decreased group performance.  相似文献   
995.
3D printing technology is a powerful educational tool that can promote integrative STEM education by connecting engineering, technology, and applications of science concepts. Yet, research on the integration of 3D printing technology in formal educational contexts is extremely limited. This study engaged preservice elementary teachers (N?=?42) in a 3D Printing Science Project that modeled a science experiment in the elementary classroom on why things float or sink using 3D printed boats. The goal was to explore how collaborative 3D printing inquiry-based learning experiences affected preservice teachers’ science teaching self-efficacy beliefs, anxiety toward teaching science, interest in science, perceived competence in K-3 technology and engineering science standards, and science content knowledge. The 3D printing project intervention significantly decreased participants’ science teaching anxiety and improved their science teaching efficacy, science interest, and perceived competence in K-3 technological and engineering design science standards. Moreover, an analysis of students’ project reflections and boat designs provided an insight into their collaborative 3D modeling design experiences. The study makes a contribution to the scarce body of knowledge on how teacher preparation programs can utilize 3D printing technology as a means of preparing prospective teachers to implement the recently adopted engineering and technology standards in K-12 science education.  相似文献   
996.
Sourav Das 《Resonance》2003,8(10):76-84
An analysis of the Madelung constant of the sodium chloride crystal lattice has been made, in an effort to supplement information available in undergraduate textbooks. A method of approximation of the constant using the personal computer is presented. An erratum to this article is available at .  相似文献   
997.
The exterior design of existing preschool environments is evaluated in the context of contemporary writings by architects focusing on creating designs that nurture children’s emotions. Sense of place research is discussed in relation to young children’s experiences. Findings reveal that the majority of sites included in the study incorporated many physical design elements that create a sense of place for children in preschool environments, including small-scale structures, windows, landscaping, natural wall materials, and thresholds. Recommendations for administrators and directors planning and designing a new or remodeled preschool environment include incorporating features that reflect home-like environments with windows, thresholds, and landscaping.  相似文献   
998.
In the context of economic globalization, international student mobility is considered increasingly important. However, due to data limitations, systematic studies to explain observed disciplinary differences are rare. Using expectancy-value-theory, we argue that this “discipline gap” in international student mobility can either be explained by a particular link to costs and/or to expected benefits. A factorial survey experiment administered to students of economics and engineering at a German university allows for a comparison of the separate consideration of both systematically varied costs and measured benefit expectations of studying abroad across both groups of students. The results reveal that disciplinary differences in the intention to study abroad are based on differently-weighted benefit potential, and not on differences in the evaluation of costs.  相似文献   
999.
The article examines the theoretical and empirical literature on higher education’s role in relation to social equity and related notions of citizenship, social justice, social cohesion and meritocracy. It considers both the education and the research functions of higher education and how these impact upon different sections of society, on who benefits and who loses from them. Questions for future research on the wider impact of higher education are posed as well as some research questions on the narrower issue of widening participation.  相似文献   
1000.
Students mainly perceive the transition to secondary school as an opportunity to start their school career anew. Reality often proves them wrong, especially in the case of mathematics. In our paper, we briefly discuss children’s transition to secondary school as both an opportunity and a problem, with reference to the Greek context. In discussions about the transition to secondary school and its effect on the teaching and learning of mathematics, primary and secondary school teachers in Greece often depict school mathematics as a “chain” of concepts and procedures. With this metaphor as our reference point, we discuss how ideologies about the teaching of mathematics are enacted in both school levels. We will base our discussion on the analysis of extracts taken from dialogues in primary and secondary school mathematics classrooms in Greece. In our analysis, we employ a Peircean view of semiotics in an attempt to conceptualize students’ rushed introduction to rigor in justifying mathematical statements in secondary school. These extracts are part of a longitudinal study that aimed, on the one hand, to pinpoint discontinuities and continuities in the teaching of geometry between primary and secondary schools and, on the other, to investigate whether a set of curriculum material that we designed could serve as a link in the teaching of geometry between the two school levels.  相似文献   
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