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131.
We shed new light on the relative importance that schools’ ability to produce high achievers in math has for economic growth. Drawing on data from the International Mathematical Olympiad (IMO), the world championship in mathematics for high school students, we construct a measure for a country’s ability to produce high achievers in math. Results from cross-country growth regressions reveal a strong and significant relationship between economic growth and IMO performance that remains even if differences in average cognitive skills among countries are taken into account.  相似文献   
132.
Sustainability is a guiding principle for a responsible, future‐oriented 21st century lifestyle and this already begins in private households with the daily household tasks. Approximately 25% of an average household's electricity consumption is required to do the laundry and dishwashing – 5% alone is for washing clothes with a corresponding energy consumption of 6 billion kilowatt hours. In addition, 600 000 tonnes of detergent and 330 million cubic metres of water are used for textile care in Germany. These figures provide the rationale for the scientific study of current practices of using washing machines and for a resulting estimate of the latent energy‐saving potential in German households. In the context of the in‐home study presented here, 236 private households throughout Germany were studied with respect to their washing practices and existing knowledge about topics on the sustainable, energy‐saving use of their washing machines. Overall, across all households 2867 wash cycles were individually recorded and subsequently analysed over a 4‐week period. The results of this study show that washing machines tend to be underloaded, and therefore maximum loading of the machines could lead to a reduction of wash cycles per household. With respect to detergent dosage, it was determined that the consumer does not adjust the dosage to the textile type, load size, soil level and/or water hardness, and this can lead to under‐ or overdosing depending on prevailing conditions. Finally, the selection of the wash temperature showed a 90°C/95°C programme was only chosen in 2.3% of all recorded wash cycles, however, every fourth cycle was completed at 60°C. Therefore, adjusting the load size and detergent dosage as well as selecting the right wash temperature are key themes to be taken into account in future consumer communication about energy‐saving households.  相似文献   
133.
So funktioniert das Konzept in den USA - über vierzig Jahre Erfahrung hat man mittlerweile in Amerika mit dem Handlungskonzept des Care und Case Managements, das dort auch seinen Ursprung hat. Grund genug für Studierende der Alice Salomon Hochschule in Berlin, ihr Wissen zu vertiefen und sich die Umsetzung vor Ort, in New York City, genau anzusehen.  相似文献   
134.
This article describes the process of a learning study conducted in technology education in a Swedish preschool class. The learning study method used in this study is a collaborative method, where researchers and teachers work together as a team concerning teaching and learning about a specific learning object. The object of learning in this study concerns strong constructions and framed structures. This article describes how this learning study was conducted and discusses reflections made during the process. Furthermore, we discuss how the learning study method could be implemented in technology education using hands-on material. Some of the results point to problems of delimiting an object of learning in technology education using hands-on material and the complexity in the relation between content and context in learning. The results also show benefits from the collaborative method where researchers and teachers work together with regards to specific learning content in the technology classroom.  相似文献   
135.
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