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1.
Eric F. Parkinson 《International Journal of Technology and Design Education》2004,14(3):219-243
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
2.
Calvyn Potgieter 《International Journal of Technology and Design Education》2004,14(3):205-218
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
3.
4.
The Graph Model for Conflict Resolution is a flexible methodology for systematically studying strategic conflicts in the real world, and is therefore a natural tool for negotiation support. The basic definitions underlying the graph model are reviewed, and the techniques for analysis and interpretation are discussed. The modeling and analysis of a case study, an international trade negotiation concerning the export of Canadian softwood lumber to the United States, are used to demonstrate the practical application of the Graph Model for Conflict Resolution as a negotiation support tool. The modeling and analysis is carried out using the GMCR software system. The ability of the Graph Model for Conflict Resolution to provide insights and advice to negotiators is emphasized. 相似文献
5.
In many previous rice trade models, the commodity has been regarded as a homogeneous product. However, homogeneity is not an appropriate assumption, given the various types of rice that are traded and consumed. Parameters estimated from these models, therefore, do not reflect the real world market for rice and, hence, may mislead decision makers who use the results for policy evaluation purposes. This study uses an Armington approach to model the world rice trade as a differential good market and to derive trade elasticity parameters. 相似文献
6.
7.
Stephanie Stray 《Quality and Quantity》2009,43(1):161-171
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
8.
Using a sample of Australian Multi-sector trusts we examine selectivity and market timing performance and extend the analysis to include the relatively new measure of volatility timing. This is of particular relevance to our data set, as high levels of volatility persistence are prevalent in Australia. In addition we consider the stability, asymmetry and seasonality of the various performance and risk measures. A survivorship adjustment procedure is also employed in order to assess the impact of survivorship on selectivity, market timing and volatility timing performance. 相似文献
9.
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
10.
Summary Competition authorities are increasingly measuring the effects of their enforcement actions, seeking a robust justification
for the proliferation of competition policy. We highlight the importance of identifying the right counterfactual against which
to measure effects, and set out the relevant categories of costs and benefits. We then explore how a balance can be struck
between the benefits and inherent limitations of these measurement exercises. Relatively crude analyses of cartel action benefits
can be sufficient to achieve public legitimacy for competition policy. Assessing the effects of merger and conduct inquiries
is often ambiguous, but could be used to improve decision-making processes.
Director and Managing Consultant, respectively, at Oxera, Oxford and London. The valuable comments of Fod Barnes, Kerry Hughes
and an anonymous referee are gratefully acknowledged. The opinions expressed in this article are those of the authors alone. 相似文献