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41.
Spatial thinking is central to many scientific domains and professions spatial ability predicts success and participation in science. However spatial thinking is not is not emphasized in our educational system. This paper presents a selective review of four types of studies regarding spatial thinking in undergraduate science curricula; (1) correlational studies examining the relations between measures of spatial ability and performance in science disciplines, (2) studies that attempt to train aspects of spatial thinking, (3) studies of how students understand specific spatial representations in sciences (4) studies that use dynamic spatial representations to promote scientific understanding. For each type of study, the evidence is critically evaluated and conclusions are drawn about how to nurture spatial thinking in science.  相似文献   
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随着计算机和通信业的迅速发展,人们对电信网络管理系统的要求越来越高,不仅需要拓扑图的显示,还要求系统能进行快速的故障定位,所以要求网管系统能与GIS系统结合.本文介绍了基于java语言的GIS系统的开发过程,及如何将GIS集成到综合电信网管系统中,并就实际开发中出现的问题提出相应的解决方案.  相似文献   
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This report presents findings from a specialist meeting of spatially-minded researchers and administrators from education and industry to consider prospects for introducing courses and curricula on spatial thinking in higher education. More than 40 participants explored the rationale for expanding student exposure to concepts, tools, and applications of spatial reasoning across a range of science, engineering, and humanities disciplines. The focus was on what we know and what we need to know to make the case for space, underscoring basic research on what is meant by spatial thinking and on variations in the spatial reasoning skills required in different domains of knowledge. The need for rigorous assessments of learning outcomes associated with different approaches to teaching spatial thinking was emphasized.  相似文献   
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负载平衡是影响并行计算性能的重要因素。针对多块结构网格,给出了一种改进的多层次图剖分负载平衡方法。该方法设计了新的网格剖分算法,采用改进的子块分裂方法与图剖分算法的循环调用实现结构对接网格剖分,并通过建立不同物体重叠网格间的连接关系,实现了结构重叠网格的负载平衡。采用2个典型算例对方法进行了对比验证,数值结果表明,子块分裂方法对剖分结果具有重要影响,采用循环调用算法及改进的子块分裂方法能有效地实现计算负载均衡及通信量优化,同时显著减少了网格块数及因虚网格导致的内存需求,有利于提高并行效率。该负载平衡方法与网格拓扑无关,适用于多块结构对接网格及重叠网格,且整体型剖分方式对于多块结构重叠网格具有更好的剖分效果。  相似文献   
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In the GRAAD Project we aimed at creatinga system which could generate route directions thatare comparable to route directions created by humanparticipants. With this goal in mind, we started froma linguistic and cognitive study of route directionsproduced by people and the study of cognitive modelsof mental maps. We proposed a new qualitative spatialmodel that can support the spatial properties of humanroute directions. This model is based on the notion ofobject's influence area which is used to modelneighborhood, orientation and distance. The proposedapproach relies on the manipulation of spatialentities in a spatial conceptual map (SCM) which isthe computarized analog of a mental map used bypeople. We developped the GRAAD System, software thatgenerates routes in a SCM and describes them innatural language. Finally, we conducted an experimentin order to compare GRAAD's route directions androutes described by human participants in similarexperimental conditions. GRAAD's output was notdistinguishable from route directions created by humanparticipants. In this paper we present the mainresults obtained during all phases of the GRAADProject.  相似文献   
48.
ABSTRACT

In three experiments, after exploring a virtual environment (VE), adult participants made spatial judgments about the location of target objects that were higher and lower than their perceived test location within the VE. In Experiment 1, the locations of the target objects were inferred from verbal instructions. The main results were a tendency to judge objects as closer to the horizontal plane than their true locations, and more efficient downward than upward judgments. Both effects generally accord with findings reported by Wilson et al. (2004a Wilson, P. N., Foreman, N., Stanton, D. and Duffy, H. 2004a. Memory for targets in a multilevel simulated environment: Evidence for vertical asymmetry in spatial memory. Memory & Cognition, 32: 283297. [Crossref] [Google Scholar], 2004b Wilson, P. N., Foreman, N., Stanton, D. and Duffy, H. 2004b. Memory for targets in a multi-level simulated-environment: A comparison between able-bodied and physically disabled children. British Journal of Psychology, 95: 325338.  [Google Scholar]). In Experiments 2 and 3, which were closely modeled on the design of the Wilson et al. studies, regression to the horizontal plane was noted but no downward bias was observed. A misperception in the viewing height between the floors and ceilings of the virtual rooms was apparent in both experiments. The results from the present study together with earlier investigations suggest different hierarchical encoding of between-axis and within-axis information.  相似文献   
49.
针对LEO卫星网络中由于流量分布不均导致的拥塞问题,以及多种通信业务带来的QoS保障问题,提出了基于区域划分的多业务QoS路由算法(MSR-RP).算法考虑了信关站有限分布造成的漏斗流量问题,一方面通过划分动态区域,减少区域节点数量,降低了算法整体计算复杂度;另一方面,在轻负载区域采用最短路径算法计算路由,重负载区域采...  相似文献   
50.
According to the Category Adjustment (CA) model, spatial estimates (e.g., of location) involve Bayesian combination across multiple, hierarchical pieces information, each weighted by its relative certainty. Recent work, though, has shown that men and women differ in terms of their certainty regarding fine-grained and categorical information in location memory. Here we demonstrate that this reflects a more general sex difference in visuospatial processing by examining bias patterns in a line angle judgment task (JLAP-15). In addition, the data suggest that multiple, hierarchical levels of categorical information influenced spatial judgments. These results imply that the hierarchical combination outlined by the CA model extends beyond two levels, and that men and women apply differential weighting to these representations.  相似文献   
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