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21.
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
22.
探讨水资源承载力综合评估和多目标计算理论在城市规划中的应用。运用灰色多层次综合评估模型对惠州市水资源承载力进行定性的综合评价,应用多目标规划理论对城市经济发展规划不同方案下的惠州市水资源承载力作了定量计算。 相似文献
23.
乡镇供水作为水利开发建设中的一个新领域,设计工作是龙头,有许多技术问题需要研究和探索,阐述了乡镇供水工程设计应注意的若干问题,并对设计中存在的一些具体问题进行了分析和探讨。 相似文献
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This paper compares the approximation capabilities of the minflex-Laurents translog and minflex generalized Leontief cost functions with their translog and generalized Leontief counterparts in Monte Carlo experiments. The minflex Laurent specifications generally provided closer approximations to underlying technical and economic parameters. Imposition of nonlinear restrictions on some of the parameters of the minflex Laurent models yielded measurable improvement in estimated elasticities of substitutions, returns to scale, and rates of technical change.The refereeing process of this paper was handled through E. Appelbaum. 相似文献
27.
We give an example of a subspace K of such that , where denotes the closure with respect to convergence in probablity. On the other hand, the cone C ≔ K − L ∞ + is dense in L ∞ with respect to the weak-star topology σ( L ∞ , L 1 ) . This example answers a question raised by I. Evstigneev. The topic is motivated by the relation of the notion of no arbitrage and the existence of martingale measures in Mathematical Finance. 相似文献
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Lead markets, innovation differentials and growth 总被引:1,自引:0,他引:1
Marian Beise 《International Economics and Economic Policy》2005,1(4):305-328
This article suggests that the specialization of countries in international trade is determined by the lead-lag market pattern of national markets. Many internationally successful innovations have been adopted first in one country while other countries initially either preferred other designs or an established product. A model for the international diffusion of innovations is presented in which nationally preferred innovation designs compete to become a globally dominant design. In this model, there are country-specific market attributes that increase the likelihood that the choice a country makes among alternative technologies is followed around the world. It is argued that technological knowledge gaps are not the origin of an international competitive advantage. Instead, a country gains a competitive advantage because a specific innovation design was adopted earlier than in any other country. This gives local firms a head start in producing, gathering marketing intelligence and securing the property rights of a globally successful innovation. In countries with lag market characteristics, domestic innovations are less likely to get adopted worldwide. Lag markets often switch from a domestic innovation design to a foreign innovation design, which increases imports. The lead-lag market explanation of trade specialization has implications for national policies. In this model domestic innovations do not always foster exports; idiosyncratic innovations induced by lag market contexts can hamper the export chances of local firms and in the end lead to an increase in imports. It is suggested that in order to increase exports, national policies have to distinguish between a domestic lead and lag market context in each industry. While in a lead market context, traditional policy instruments that enhance the rate of innovations are effective, in a lag market situation national follower strategies are more appropriate. 相似文献
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