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基于扫描统计量的微博中突发事件舆情动态监测方法 被引量:9
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作者 裘江南 杨书宁 翟劼 《情报学报》 CSSCI 北大核心 2015年第4期414-423,共10页
针对目前关于突发事件的网络舆情监测研究中缺乏连续动态监测的方法的问题,提出了基于扫描统计量的微博中突发事件舆情监测方法。本文首先对微博中的网络舆情要素进行分析,提出了基于用户信息量和微博项信息量的计量方法。进而,提出... 针对目前关于突发事件的网络舆情监测研究中缺乏连续动态监测的方法的问题,提出了基于扫描统计量的微博中突发事件舆情监测方法。本文首先对微博中的网络舆情要素进行分析,提出了基于用户信息量和微博项信息量的计量方法。进而,提出了基于时间扫描统计量的微博中的网络舆情监测方法,具体包括时间扫描变量及概率分布模型确定、微博数据时间扫描窗口定义、时间扫描窗口对数似然比计算、对聚集窗口的非随机性进行显著性分析。最后,通过实验对比验证了该方法的有效性。解决了目前在突发事件相关的网络舆情监测中舆情爆发时间点无法进行有效判断的问题,同时为网络舆情的监测研究提供了一个连续动态监测的方法。 展开更多
关键词 网络舆情 舆情监测 突发事件 微博扫描 统计量
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Investigation of Metal Wired Coloured Historical Textile Using Scanning Electron Microscopy and HPLC-DAD
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作者 Turkan Yurdun Seher Karsli-Ceppioglu R. Gurcan Oraltay 《Journal of Chemistry and Chemical Engineering》 2012年第7期591-598,共8页
SEM-EDS (scanning electron microscopy-energy dispersive spectrometry) and HPLC (high performance liquid chromatography) with DAD (diode array detection) were used to examine metal-wrapped coloured textiles. The ... SEM-EDS (scanning electron microscopy-energy dispersive spectrometry) and HPLC (high performance liquid chromatography) with DAD (diode array detection) were used to examine metal-wrapped coloured textiles. The sample was provided from Azerbaijan History Museum. Material included silk and thin wire. SEM micrographs showed that the metal strip had 250μm width and 6 9m thickness. SEM-EDS results indicated elemental composition of the wrapping: the presence of gold, silver as the components of the gilt metals. Furthermore, sulphur and chlorine were determined as contaminants. EDS analysis also revealed that both sides were gildered. Colouring compounds in the same sample were identified by HPLC-DAD. The major colouring compound found in the red fibre sample in large quantity was carminic acid and fuchsin components. The presence of fuchsin, which is a synthetic dye, dates the sample between the end of 19th and beginning of 20th century. Fisetin, which is a natural dye, was detected in the yellow fibre. 展开更多
关键词 TEXTILE DYE HPLC SEM.
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