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951.
Chiung-Fen?YenEmail author Tsung-Wei?Yao Yu-Chih?Chiu 《International Journal of Science and Mathematics Education》2004,2(2):159-174
This study examined students alternative conceptions of reptiles and amphibians and the extent to which these conceptions remain intact through the elementary (grades 4 and 6), junior, and senior high school years. We administered multiple-choice and free-response instruments to a total of 513 students and interviewed at least 20 students at each educational level to get an in-depth view of their original conceptions. Then, we developed and administered a two-tier multiple choice diagnostic instrumentto assess various levels of students understanding of amphibians and reptiles(N=1267). The results showed that most students were able to classify snakes as reptiles, whereas fewer than 30% of the students across different ages classified sea turtles as reptiles; the remaining 70% classified sea turtles as amphibians. More students were able to correctly classify frogs as amphibians than toads. In most instances, students correctly classified prototypical representatives of the two animal classes more readily than less exemplary representatives, a finding that supports previous research (Trowbridge, J.E. andMintzes, J.J. (1988). Alternative conceptions in animal classification: A cross-age study. Journal of Research in Science Teaching, 25(7), 547–571). Interestingly, the alternative views of sea turtles as amphibians remained intact throughout the school years. Interview data indicated that students classified sea turtles as amphibians largely because sea turtles are able to live in terrestrial and aquatic habitats. Semantically, amphi means living on land and in water. When asked to distinguish between reptiles and amphibians and to classify several species into those two groups, a wide range of alternative conceptions emerged and the origin of those alternative conceptions are discussed. Similar results were obtained when we applied a two-tier multiple-choice diagnostic instrument to assess students understanding of amphibians and reptiles. 相似文献
952.
Great efforts have been made to resolve the serious environmental pollution and inevitable declining of energy resources. A review of Chinese fuel reserves and engine technology showed that compressed natural gas (CNG)/diesel dual fuel engine (DFE) was one of the best solutions for the above problems at present. In order to study and improve the emission performance of CNG/diesel DFE, an emission model for DFE based on radial basis function (RBF) neural network was developed which was a black-box input-output training data model not require priori knowledge. The RBF centers and the connected weights could be selected automatically according to the distribution of the training data in input-output space and the given approximating error. Studies showed that the predicted results accorded well with the experimental data over a large range of operating conditions from low load to high load. The developed emissions model based on the RBF neural network could be used to successfully predict and optimize the emissions performance of DFE. And the effect of the DFE main performance parameters, such as rotation speed, load, pilot quantity and injection timing, were also predicted by means of this model. In resume, an emission prediction model for CNG/diesel DFE based on RBF neural network was built for analyzing the effect of the main performance parameters on the CO, NOx emissions of DFE. The predicted results agreed quite well with the traditional emissions model, which indicated that the model had certain application value, although it still has some limitations, because of its high dependence on the quantity of the experimental sample data. 相似文献
953.
For a long time after the proclamation of independence, Croatia suffered economic stagnation that negatively affected the development of science and higher education. However the turn of the millennium brought higher state investment in science and higher education, and all statistics now show a steady increase in the number of students and scientific personnel for the past several years. With these trends the focus has moved from the role the state can play in reviving science in Croatia to the necessity of greater participation in scientific funding, as well as the role that university graduates can play in the development of the country. The role of European integration and the brain drain phenomenon thus increase in importance, and this study provides some parameters for brain drain and the academic and intellectual labour market in Croatia. 相似文献
954.
Anette?SandbergEmail author Ingrid?Pramling-Samuelsson 《Early Childhood Education Journal》2005,32(5):297-305
The aim of this study was to investigate, identify and describe different ways that female and male preschool teachers conceive, understand and experience play. The research questions addressed are: What perspectives do female and male preschool teachers have on play? Are there differences in play experiences related to gender? The interview study is inspired by phenomenographical research. The sample consisted of ten female and ten male preschool teachers’. The results show differences between female and male preschool teachers’ play willingness. This study found that male preschool teachers contribute with more playfulness, and this is something that both female and male preschool teachers noticed. Female preschool teachers tend to value calm play and emphasize the importance of social development while male preschool teachers accentuate the significance of physical development. All preschool teachers in the study emphasized that it is important to create inspiring environments for play and outdoor play. 相似文献
955.
Sheau-Wen?LinEmail author 《International Journal of Science and Mathematics Education》2004,2(2):175-199
This study involved the development and application of a two-tier diagnostic test measuring students understanding of flowering plant growth and development. The instrument development procedure had three general steps: defining the content boundaries of the test, collecting information on students misconceptions, and instrument development. Misconception data were collected from interviews and multiple-choice questions with open response answers. The data were used to develop 13 two-tier multiple-choice items. The conceptual knowledge examined was flowering plant life cycles, reproduction, precondition of germination, plant nutrition, and mechanism for growth and development. The diagnostic instrument was administered to 477 high school students. The correlation coefficient of test-retest was 0.75. Difficulty indices ranged from 0.24 to 0.82, and discrimination indices ranged from 0.32 to 0.65. Results of the Flowering Plant Growth and Development Diagnostic Test suggested that students did not acquire a satisfactory understanding of plant growth and development concepts. Nineteen misconceptions were identified through analysis of the items that could inform biology instruction and resource. 相似文献
956.
In Part I, the nature of scalars and vectors was discussed for the Newtonian world. However, in the relativistic world, physical
quantities follow Lorentz transformations. This change of transformation from Galilean to Lorentz results in interesting distinctions
in their properties: mass and time are no longer scalars, time and space become intertwined, etc. This part discusses the
nature of scalars and vectors in the relativistic world. 相似文献
957.
Our study addresses the need for new approaches to prepare novice elementary teachers to teach both science and engineering, and for new tools to measure how well those approaches are working. This in particular would inform the teacher educators of the extent to which novice teachers are developing expertise in facilitating their students’ engineering design work. One important dimension to measure is novice teachers’ abilities to notice the substance of student thinking and to respond in productive ways. This teacher noticing is particularly important in science and engineering education, where students’ initial, idiosyncratic ideas and practices influence the likelihood that particular instructional strategies will help them learn. This paper describes evidence of validity and reliability for the Video Case Diagnosis (VCD) task, a new instrument for measuring pre-service elementary teachers’ engineering teaching responsiveness. To complete the VCD, participants view a 6-min video episode of children solving an engineering design problem, describe in writing what they notice about the students’ science ideas and engineering practices, and propose how a teacher could productively respond to the students. The rubric for scoring VCD responses allowed two independent scorers to achieve inter-rater reliability. Content analysis of the video episode, systematic review of literature on science and engineering practices, and solicitation of external expert educator responses establish content validity for VCD. Field test results with three different participant groups who have different levels of engineering education experience offer evidence of construct validity. 相似文献
958.
Dana?CocargeanuEmail author Eithne?O’Connell áine?McGillicuddy 《Children‘s Literature in Education》2016,47(4):374-391
This year, 2016, marks the 150th anniversary of the birth of Beatrix Potter (1866–1943), the much-loved author and illustrator of children’s books. Although translation has made a vital contribution to her international success, Potter’s work remains relatively under-researched from a translation studies perspective. This article aims to provide a clearer picture of Potter’s work in translation over the last hundred years. It identifies early translated editions and discusses Potter’s involvement in their preparation, before examining the appearance of her stories in translation around the world and outlining particular trends in Potter translation. This study is based on extensive research using numerous databases, Potter’s published biographies and correspondence, and on an analysis of the first French editions of her tales. The study reveals that the first published translations of Potter’s works are both of an earlier date and more numerous than is recognised in existing scholarship. It also shows that Potter’s preferred approach in the translation of her stories into French was to adapt the tales to their new French readership, rather than staying close to the originals. Her works are found to have been extensively translated during the last century, especially into European languages, as well as into a significant number of Asian languages. Other matters discussed include the involvement of Potter’s official publisher, Warne, in the publication of international editions; the existence of translations based on American editions with new illustrations; and the posting of online translations by Potter enthusiasts. 相似文献
959.
Parents and researchers alike are interested in how to promote children’s academic competence. The present meta-analysis integrates the results of 308 empirical studies on associations of general parenting dimensions and styles with academic achievement of children and adolescents assessed via grade point average or academic achievement tests. Parental responsiveness (warmth), behavioral control, autonomy granting, and an authoritative parenting style were associated with better academic performance both concurrently and in longitudinal studies, although these associations were small in a statistical sense. Parental harsh control, and psychological control, as well as neglectful, authoritarian, and permissive parenting styles were related to lower achievement with small to very small effect sizes. With three exceptions, parenting dimensions and styles also predicted change in academic achievement over time. Moderating effects of child age, ethnicity, reporter on parenting and academic achievement, quality of the parenting and achievement measure, and publication status were identified. It is concluded that associations of academic achievement with general parenting dimensions/styles tend to be smaller than associations of school-specific parental involvement which have been addressed in previous meta-analyses. 相似文献
960.
Moving ships and other objects drifting on water often impact a bridge's pile foundation. The mechanical model of the piles-bridge
structure under horizontal forcing was established, and a time-domain approach based on Finite-difference Method was developed
for analyzing the dynamic response of the piles-bridge structure. For a single pile, good agreement between two computed results
validated the present approach. The slenderness ratio of the pile, the pile-soil stiffness ratio and the type of the structure
influence the dynamic response of the piles-bridge structure. The computed results showed that the stiffness of the structure
determines the dynamic response of the piles-bridge structure under horizontal forcing.
Project (No. 001110442) supported by the Science and Technology Bureau of Zhejiang Province, China. 相似文献