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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   
64.
Abstract The research question in the present article can be phrased in the following way: what are the elements which influence the perception of the utility of information received from another function? A field study research has been conducted in 40 Belgian companies. In each company, we have studied two on-going innovation projects (one planning project, one development project). Crossfunctional communication behaviours at the R&D/marketing interface have been measured by means of mailed structured questionnaires. Three-hundred and eighty-six questionnaires have been returned. The data analyses show that there are four underlying information dimensions, i.e. the perceived relevance, the perceived comprehensibility, the perceived novelty and the perceived credibility of information. We also discuss some contingency variables (function of the message receiver, stage in the innovation process) that might moderate the impact of these dimensions. It will be shown that the interaction between source and receiver has a significant impact on the perceived credibility, the perceived comprehensibility and the perceived novelty of the received information.  相似文献   
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The paper extends Manning's model on education and balanced growth to include labour immigration. Each immigration unit is assumed to consist of one skilled worker and some unskilled members. The optimal immigration policy which maximizes the per capita steady-state consumption of the host country is derived. We show that optimal immigration policy can reduce the steady-state skilled labour ratio. More interesting still, contrary to the widespread belief that immigration of skilled workers hurts local skilled workers, it is the unskilled local workers whose interests are threatened by optimal immigration policy.  相似文献   
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The introduction of traffic management schemes has been one response of the National Parks to the problem of ever-increasing car-borne visitors and the consequent damage caused to the rural environment. By reviewing these schemes and by determining and explaining attitudes towards one particular traffic management experiment, the paper aims to deduce lessons for future policy. The analysis, based on two visitor surveys, suggests that the likelihood of success is improved when schemes are integrated, containing both ‘carrot’ and ‘stick’ elements. Since public perceptions are also found to be pivotal to its success, appropriate marketing of a scheme is vital. The paper concludes, however, that to achieve the fundamental objective of greater accessibility with less mobility, a more wide-ranging marketing effort is required intended to engender a sea change in attitude towards both the car and public transport.  相似文献   
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The paper deals with effects of price changes on measurement of poverty. It is shown that there are situations, when prices and nominal incomes change, a higher nutritional intake or an increase in commodity consumption of the poor can be associated with higher poverty gaps and a higher poverty index of the society. A positive relationship of this kind is quite counter-intuitive in the context of poverty measurement. This is caused by the adjustment of the poverty line and/or incomes of one situation by the prices of the other for the purpose of comparison.

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This study examines whether the uncertainty arising from a firm's exposure to future environmental costs (environmental uncertainty) affects the market's price sensitivity to reported earnings. Specifically, when environmental uncertainty is significantly high, are investors more responsive to reported earnings released by 'high-polluting' firms than reported earnings announced by 'low-polluting' firms within the same industry? The initial impact of Title IV (the acid rain provisions) of the 1990 Clean Air Act Amendments (1990 CAAA) on the US electric utility industry provides the research setting required to isolate the effects of environmental uncertainty while addressing this question. Consistent with theoretical predictions, we find that the earnings response coefficients (ERCs) of high-polluting electric utilities are significantly greater than those of their low-polluting counterparts during a predicted period of elevated environmental uncertainty. In adjoining sample years associated with lower environmental uncertainty, we observe no statistical difference in the magnitude of the ERCs between these two groups. In addition, the study's findings suggest that the magnitude of the ERC is increasing in the firm's exposure to future environmental costs, after controlling for other factors that potentially affect ERCs.  相似文献   
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