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1.
The voucher model of financing schooling is becoming increasingly common throughout Latin America, with at least 12 countries using vouchers or voucher-like schemes. The present study focuses on the voucher models of Colombia and Chile, which have the most extensive programs of this type and those of the longest standing in the region. Using empirical evidence, the author compares the two models along four evaluative dimensions: educational quality, segregation, choice and socialization. After weighing the successes and weaknesses of each system, he concludes that, among other characteristics, the most effective and equitable voucher model features: (a) a flexible interpretation of educational quality; (b) financial grants which target solely the poor; (c) vouchers which cover the entire cost of tuition; (d) open enrolment at participating schools; (e) the participation of both secular and religious private schools; (f) accessible and meaningful information to parents; and (g) strong systems of accountability.  相似文献   
2.
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   
3.
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   
4.
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   
5.
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   
6.
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   
7.
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   
8.
音乐剧是音乐美育中一个重要的分支,是多种艺术交叉的一门学科,具有很强的综合性,涉及知识面极广.探讨了将赏析音乐剧纳入音乐欣赏课程的策略,旨在调动高职学生学习音乐剧的积极性,培养学生的想象力和创造力,提高其审美能力.  相似文献   
9.
在职业教育提职培优新阶段的背景下,基于逆向教学设计的方法,构建高职大学语文课程体系,创新教学方法,并探索新教学模式,旨在凸显高职语文课程教育特点,促进课堂革命,为创新公共基础课程模式提供思路.  相似文献   
10.
创新教育是高职院校强调学生主体地位和学生学习价值的重要教学理念.教师要了解健美操教学在课程知识、舞蹈动作等方面的整体教学方向.阐述了创新教育在教学方法和舞蹈编排中的应用,并提出了健美操教学在多媒体技术、体育教学理论和教师活动组织等方面的实践路径.  相似文献   
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