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71.
为了提高灰色GM(1,1)模型在城市用水量预测中的精度,结合BP神经网络的优点,给出了两种灰色-神经网络组合模型GM-BP1和GM-BP2.模型1利用神经网络对GM(1,1)模型的误差序列进行回归训练,将得到的预测值作为原始误差的修正来减小误差;而模型2由部分数据建立了GM(1,1)模型组,通过神经网络训练得到部分数据GM(1,1)模型组与真实值之间的非线性映射关系,利用这种精准的映射关系来提高预测精度.最后实际算例表明了所给方法是有效的,该组合模型可用于城市用水量的中长期预测.  相似文献   
72.
Over the last decade in the UK, there has been a notable shift in the popularity and use of cultural mapping as a methodology for policy making at a regional and local level. This follows increased demand for an informed framework for planning arts and cultural facilities from local and regional government and from within the cultural sector (Evans, 2008: p. 65). The article begins with an exploration of cultural mapping within cultural policy, which explores the context for the growth in this area of activity, and why this kind of activity appeals to policy makers and organisations. It then goes on to examine four cultural mapping exercises which have been undertaken in recent years in the UK. These studies have been chosen because although they all focus the mapping of cultural assets within a specific geographic area, they differ to one degree or another in purpose, context, definition, geographic scale and methodology. They illustrate the narrow range of approaches deployed in the cultural mapping field in the UK, and as such provide a useful means of critically reviewing their limits as well as highlighting the issues and challenges faced by cultural cartography in practice. The article concludes by considering the type of mapping research that is “allowed” within the discursive confines of consultancy based cultural policy research.  相似文献   
73.
The method of bibliographic coupling in combination with the complete link cluster method was applied for mapping of the field of organic chemistry with the purpose of testing the applicability of a proposed mapping method on the field level. The method put forward aimed at the generation of cognitive cores of documents, so-called ‘bibliographic cliques’ in the network of bibliographically coupled research articles. The defining feature of these cliques is that they can be considered complete graphs where each bibliographic coupling link ties an unordered pair of documents. In this way, it was presumed that coherent groups of documents in the research front would be found and that these groups would be intellectually coherent as well. Statistical analysis and subject specialist evaluations confirmed these presumptions. The study also elaborates on the choice of observation period and the application of thresholds in relation to the size of document populations.  相似文献   
74.
金庸是当代武侠小说的艺术大师。他的武侠小说背叛了传统武侠小说的“男女授亲不亲”,继承了“侠义”;以平常的笔触描写民族战争;以民为本;用“帮派”之争映照社会。具有古典浪漫主义的艺术特色。  相似文献   
75.
在线用户教育是Library2.0核心思想在图书馆用户教育方面的实践。Library2.0工具在支持交互、共享、个性化服务方面极具优势,对完善在线用户教育的功能体系有极其重要的作用。笔者分别就BLOG、RSS、WIKI在高校图书馆在线教育中的应用提出了构想,以期对实践工作有所启示。  相似文献   
76.
在单值映象与集值映象相容或次相容的条件下,给出了完备凸度量空间中集值映象对于单值映象存在公共不动点的一个充分条件,改进和推广了文[1-4]中的已知结果。  相似文献   
77.
介绍了一种基于STM32F0xx的智能温湿度控制器的设计方法及功能实现;该控制器可实现控制柜内温湿度控制和控制柜内外温湿度显示。  相似文献   
78.
运用科学计量方法对国外企业孵化网络的研究成果进行分析,探索出"核心-衍生"动态拓展模型,其中核心领域包含"专业化能力"以及"联盟孵化"两个视角。衍生领域包含"产业升级"和"知识管理"两个视角。  相似文献   
79.
以CSSCI数据库收录的以信息共享空间为主题的论文为基础数据,通过Citespace3.8R1软件对相关引文数据和主题词数据进行处理,绘制出信息共享空间领域的知识图谱,并对其进行分析,得出我国信息共享空间领域的重要学术文献及学术代表人物、主要研究热点及研究前沿等。  相似文献   
80.
Disagreements exist in the literature regarding the manner in which weight should be dynamically shared during the golf swing, both within-feet and between the back- and target-foot, to generate maximal clubhead speed. The purpose of this study was to determine whether preferential foot-loading locations underlie weight sharing by examining the correlation between clubhead speed and maximum plantar pressure (PP) distributions. Thirty-two amateur golfers with handicap indexes ranging from 2.7 to 25 performed 10 driver swings on artificial turf following a warm-up. PP distributions were recorded at 100 Hz, and clubhead speed was recorded using a ball-tracking Doppler radar system. Maximum PPs were extracted from a 2-s window approximately centred on ball contact and were regressed against clubhead speed. Significance was assessed over the entire foot surface using statistical parametric mapping (SPM), a spatially continuous technique. SPM revealed, at relatively high anatomical resolution, significant positive correlations between clubhead speed and PPs in the lateral target-foot (P < 0.05). This suggests that not only weight transfer but also weight-transfer location may be an important determinant of clubhead speed in amateur golfers.  相似文献   
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