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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.
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   
5.
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   
6.
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   
7.
In this paper we review several issues associated with post project review and dissemination of knowledge in information technology projects. We reflect on our practice of coaching project teams. In identifying the role of social pressure in forming teams’ perception of their performance, we suggest what could potentially be an interesting and fruitful avenue of future research on an approach to post project review and dissemination of knowledge in organizations.  相似文献   
8.
本文研究以资源依赖理论为基本理论,从技术经济分析的理论入手,一是分析了技术标准战略联盟的形成机理;二是研究了技术标准联盟的资源分类,分析了技术标准联盟资源聚合的内在机理,论证了影响技术标准战略联盟的影响因素;三是在此基础上,从技术联盟的机制和要素分析入手,研究了技术标准战略联盟的不同模式及各个模式的运作方式及相互转换机制。  相似文献   
9.
The concept of privacy as a basic human right which has to be protected by law is a recently adopted concept in Thailand, as the protection of human rights was only legally recognized by the National Human Rights Act in 1999. Moreover, along with other drafted legislation on computer crime, the law on privacy protection has not yet been enacted. The political reform and the influences of globalization have speeded up the process of westernization of the urban, educated middle-class professionals. However, the strength of traditional Thai culture means that a mass awareness of the concept of privacy rights remains scarce. This paper explicates the Thai cultural perspective on privacy and discusses the influence of Buddhism on privacy rights, including the impacts of globalization and the influence of Western values on the country’s political and legal developments. The paper also discusses the legal provisions regarding privacy protection, and the debates on the smart ID cards policy and SIM cards registration for national security.  相似文献   
10.
In light of growing concerns in the public and recent mandates from business program accrediting bodies and curricular task forces, the importance of teaching ethical topics in information systems programs is discussed. Innovative strategies used for teaching the application of ethical criteria to common situations are reviewed. Results of a survey of information systems faculty members in the US are presented and are compared to previous studies that related primarily to computer science and software engineering programs. Insight is provided into the topics, techniques, degree of coverage, and assessment techniques currently used when teaching ethics in computing-related programs. Key concerns and future work is also outlined.  相似文献   
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