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61.
Construction kits have played a significant part in nurturing the growth and development of the minds and manipulation-based skills of children (and adults) in formal and non-formal education settings. These kits have origins rooted in the representation of the built world and now have a diversity of form and function, including technical versions with moving parts. This article examines some of the historically based ideas that lie behind the role that kits may have in terms of physical modelling. The article traces the transformation of kits from simple bricks and blocks into more complicated pieces for space-filling and achieving the transfer of forces and motion. This transformation occurred during the Victorian era when the influence of the ideas of educationalists and, perhaps rather strangely, exponents of early aviation, played major roles in determining the diversity of forms of construction kit and modelled possibilities that are now to be seen in classrooms and homes. The article ends with a review of some of the lessons from the past and present that will need to be considered in relation to concrete modelling in schools for the future. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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In this article the impact of technology education, as a new learning area (subject) in the curriculum, on in-service teacher education in South Africa is described in order to ascertain the extent of the impact. The research on which this article is based draws on a variety of experiences and observations in the field at grassroots level (in particular an outreach project in rural communities). The envisaged impact of technology education on South African schools, communities, teacher educators and teachers, the range of in-service teacher education that is required, and the impacts in urban and rural areas are discussed. Finally a number of concluding remarks are made about the extent of the impact of the inclusion of technology education in the new National Curriculum Statement and whether the situation has changed since the implementation of a pilot technology education project in 1998. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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We examine data for the year ended December 31, 1997 for 80 publicly traded property‐liability insurers that have Best financial strength ratings of their consolidated insurance‐operating subsidiaries. These firms employ a holding company structure, in which a parent owns the stock of multiple insurance‐operating subsidiaries. The operating subsidiaries prepare a consolidated annual report using the Statutory Accounting Principles (SAP), and an analogous set of financial statements based on the Generally Accepted Accounting Principles (GAAP) is released by the parent. We find that the financial characteristics important in determining ratings at the individual firm level—capitalization, liquidity, profitability, and size—are also important at the group level. Further, financial ratios from holding company statements are incrementally useful in the ratings' process, after group‐level ratios have been taken into account. Robustness tests based on a subsample of holding companies with minimal investment outside of the property‐liability industry reinforce our conclusion that parent company statements influence consolidated group ratings. However, our data do not allow us to separate the relative contribution of the GAAP model and underlying transactions to the ratings decision.  相似文献   
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That survey research is error prone is not a new idea and different varieties of non-sampling error have been investigated in the literature as well as consideration being given in many statistics textbooks to the issue of sampling error. The paper here considers research upon corporate environmental reporting. It compares information provided by corporate environmental reports with information that survey respondents claim their organization’s environmental report contains. This enables the accuracy of the claims to be assessed. Consideration is given to two different industries the Water industry and the Energy industry. Errors due to inaccurate reporting by survey respondents are shown to be relatively infrequent and respondents appear just about as likely to claim they report information that they do not, in fact, report as to fail to indicate that they report information that is, in fact, actually reported.  相似文献   
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This paper re-examines the evidence on open market share repurchase activity reported by Rau and Vermaelen (2002) for the UK. Using data from the Securities Data Corporation (SDC), Rau and Vermaelen conclude that the level of repurchase activity is trivial. They attribute the low repurchase volume to regulatory restrictions that limit companies' ability to take advantage of an undervalued stock price and conclude that the bulk of repurchase activity that does occur is driven by the desire to generate tax credits for pension funds. Using data collected from a variety of sources, we find that the SDC substantially understates UK open market buyback activity. Based on our more comprehensive dataset we conclude that (a) pension funds' tax considerations are not the primary cause of UK share repurchases and (b) despite the prevailing regulatory environment, underpricing still represents an important determinant of repurchase activity.  相似文献   
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This article specifies what an optimal pollution tax should be when dealing with a vertical Cournot oligopoly. Polluting firms sell final goods to consumers and outsource their abatement activities to an environment industry. It is assumed that both markets are imperfectly competitive. Thus, the tax is a single instrument used to regulate three sorts of distortions, one negative externality and two restrictions in production. Consequently, the optimal tax rate is the result of a trade-off that depends on the firms’ market power along the vertical structure. A detailed analysis of Cournot-Nash equilibria in both markets is also performed. In this context, the efficiency of abatement activities plays a key-role. It gives a new understanding to the necessary conditions for the emergence of an eco-industrial sector.   相似文献   
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