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21.
Based on theories of scientific discovery learning (SDL) and conceptual change, this study explores students' preconceptions in the domain of torques in physics and the development of these conceptions while learning with a computer-based SDL task. As a framework we used a three-space theory of SDL and focused on model space, which is supposed to contain the current conceptualization/model of the learning domain, and on its change through hypothesis testing and experimenting. Three questions were addressed: (1) What are students' preconceptions of torques before learning about this domain? To do this a multiple-choice test for assessing students' models of torques was developed and given to secondary school students (N = 47) who learned about torques using computer simulations. (2) How do students' models of torques develop during SDL? Working with simulations led to replacement of some misconceptions with physically correct conceptions. (3) Are there differential patterns of model development and if so, how do they relate to students’ use of the simulations? By analyzing individual differences in model development, we found that an intensive use of the simulations was associated with the acquisition of correct conceptions. Thus, the three-space theory provided a useful framework for understanding conceptual change in SDL. 相似文献
22.
《Urban Research & Practice》2013,6(3):353-359
This article focuses on the Stuttgart Region's Landscape Park concept, which is an instrument for the balanced development of open spaces within a densely populated region. The Stuttgart Region covers 5 counties and 179 independent municipalities over an area of 3650 square kilometres in the southwestern part of Germany. The competences of the Verband Region Stuttgart cover not only (mandatory) regional planning and spatial development, but also the construction and operation of the regional railway system, economic development and marketing. In this context, the Landscape Park has been introduced to enhance the ecological quality and recreational value of open spaces. By now, it has become a successful instrument which helps local institutions to develop green infrastructure as an important locational factor. 相似文献
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《Material Religion》2013,9(2):142-155
ABSTRACTIntroducing the themes and contexts for this special issue of the journal, this editorial reflects particularly on the experience of museums and museum and heritage educators in the UK and Asia in interpreting religions and religious art. It looks at successful examples of specialist museum programs and exhibits on religions; and distance learning resources that include faiths in suggesting new approaches to citizenship education through cultural learning. It looks more broadly at new approaches to religious education that encompass sacred spaces. 相似文献
25.
随着中国城镇化进程发展,人口密集、土地资源短缺等问题使得最具活力却拥挤的城市中心区亟需扩张。城市中心广场逐渐向下发展,而地下空间早期粗放型开发模式导致城市中心广场上下割裂。出入口空间在其中承担沟通上下的重要作用,且目前仍存在空间使用效率低下、吸引力不足等问题。文章以城市中心广场地下街出入口行为活动为导向,总结不同类型地下街出入口空间的上下联动行为需求及现状问题,从形态组织、文化功能、通行效率、安全可达四个方面提出城市中心广场地下街出入口空间上下联动设计策略。 相似文献
26.
The aim of this paper is to study the thermal comfort levels achieved in open spaces by means of evaporative wind towers. These systems have been installed in an urban area characterized by its hot and dry summer climate. Conventional wind tower designs for enclosed and semi-enclosed spaces have been adapted for this new installation. These systems are usually composed of a few number of wind towers, this one however is composed by a group of sixteen, increasing the total dimensions of the installation. To integrate this construction into the urban public area, it was built in a circular arrangement, creating an activity and meeting point for pedestrians. This passive system was monitored during the summer of 2008. Measurements of temperature, solar radiation, humidity and wind speed were analyzed. During the analyzed period, the average cooling efficiency of the system varied from 38% at the exit of the tower, to 32% at 1 m high. At this last position, the average exceeds the wet bulb temperature up to 8 °C with an increase of moisture around 27%. The shading effect produced by the global installation itself has been modeled theoretically to evaluate the incident solar radiation at the pedestrian area. Two indices have been applied to predict the perception of heat and cold in the south pedestrian zone: Heat index and TS index. In this position, both variables approached the thermal sensation to the comfort levels by the use of these passive strategies when ambient conditions are hot and dry. 相似文献
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Zhiyong Feng Zhiqing Wei Qixun Zhang Wei Li Xin Wang Yi Qian 《Wireless Communications and Mobile Computing》2016,16(13):1876-1890
For the problem of spectrum scarcity and wastage, cognitive radio (CR) technology provides a solution to utilizing the vacant spectrum more efficiently. As one of the most promising techniques to obtain the cognitive information in TV white spaces, geo‐location database approach has attracted a lot of recent attentions, with its goal of enhancing the efficiency of spectrum usage and avoiding the interference to TV receivers. However, existing works mainly focus on the construction and applications of geo‐location database, and seldom consider how to deliver the cognitive information from the database to TV band devices. In this paper, we investigate the tradeoff between increasing the accuracy of cognitive information delivery and reducing the overhead. We design two mesh fusion algorithms to reduce the redundancy of cognitive information and improve the efficiency of cognitive information delivery. Finally, we verify our analysis and evaluate the efficiency of the proposed mesh fusion algorithms through numerical studies. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
29.
从医院环境空间、心理需求和管理创新三个方面出发,分析了空间环境对病人生理、心理和行为的影响,指出医院公共空间的设置应契合使用者对医院总体空间的使用需求,从而提高医疗建筑的质量,实现以人为本的理念。 相似文献
30.
利用核函数Ω的性质,证明了带可变核的参数型Marcinkiewicz积分算子μρΩ,0与μρΩ∞,"在Companato空间εα,p上的一个不等式关系. 相似文献