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一种通用的敏感度数据统计分析方法
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作者 徐义根 刘尚合 魏光辉 《火工品》 CAS CSCD 北大核心 1997年第4期21-23,共3页
根据敏感度数据的特点,以最大似然估计理论为基础,建立了一般形式的敏感度数据的似然函数以及用Newton迭代法进行求解的方法,并用FORTRAN5.1语言编制了计算机演算程序。
关键词 敏感度数据 最大似然法 统计分析 火工品
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数据源敏感的多源XML数据相似度量方法
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作者 王继奎 李少波 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2014年第7期28-32,共5页
将预处理后的XML数据当作文本信息采用词频-逆向文档频率(TF-IDF)模型进行处理时,逆向文档频率作为词项权重有其不足之处.为此,文中定义了词项的数据源敏感度作为逆向文档频率(IDF)的修正系数.其值取决于提供此词项的数据来源于不同数... 将预处理后的XML数据当作文本信息采用词频-逆向文档频率(TF-IDF)模型进行处理时,逆向文档频率作为词项权重有其不足之处.为此,文中定义了词项的数据源敏感度作为逆向文档频率(IDF)的修正系数.其值取决于提供此词项的数据来源于不同数据源的概率,概率大则其值大,反之则其值小.然后在修正后的词项权重向量的基础上,定义了相似度函数.最后在模拟、真实数据集上进行数据重复检测实验.结果表明,新方法获得了更高的F测度值.这说明考虑词项的数据源敏感度可提高相似度函数的有效性. 展开更多
关键词 XML 数据集成 文本处理 数据敏感度
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Solubility of Emodin in Alcohols 被引量:3
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作者 吕阳成 林泉 +1 位作者 骆广生 戴猷元 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第2期251-253,共3页
Emodin is a kind of anthraquiones with pharmaceutical activities.The solubilities of emodin in ethanol,1-octanol,and ethanol+1-octanol at different temperatures were measured using an analytical method.The solubility ... Emodin is a kind of anthraquiones with pharmaceutical activities.The solubilities of emodin in ethanol,1-octanol,and ethanol+1-octanol at different temperatures were measured using an analytical method.The solubility of emodin in these solvents increased with an increase in temperature.With the temperature deviating from room temperature,the dependence of the solubility of emodin on temperature became a lot more remarkable.The solubility of emodin in ethanol was more sensitive to temperature than that in 1-octanol.The solubility data of emodin in the same species of solvent at different temperatures was correlated with an empirical equation.The calculated results agreed with the experimental data well. 展开更多
关键词 SOLUBILITY EMODIN ETHANOL 1-octanol
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Determination and Correlation of Solubilities of Four Novel Benzothiazolium Ionic Liquids with PF_6^- in Six Alcohols
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作者 何志坚 王小敏 +2 位作者 姚田 宋航 姚舜 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第4期435-446,共12页
Four novel benzothiazolium ionic liquids with 6PF?([C1Bth][PF6], [C4Bth][PF6], [C5Bth][PF6] and [C6Bth][PF6]) were synthesized, and the rang of their melting points were determined between 358.35 K-424.05 K. The relat... Four novel benzothiazolium ionic liquids with 6PF?([C1Bth][PF6], [C4Bth][PF6], [C5Bth][PF6] and [C6Bth][PF6]) were synthesized, and the rang of their melting points were determined between 358.35 K-424.05 K. The relationship of their melting points and the length of the straight alkyl chain on cation reflected ‘S' type ten-dency. Then, the solubilities of the four ionic liquids in six lower alcohols(methanol, ethanol, 1-propanol, 2-propanol, 1-butanol and 2-methyl-1-propanol) were measured in the temperature rang of 253.15-383.15 K at at-mospheric pressure with static analytical method, respectively. It was found that [C6Bth][PF6] in all investigated ionic liquids had the largest solubility in six alcohols and the solubility of [C4Bth][PF6] in methanol was very sensi-tive for temperature in 313.15-333.15 K, which was so-called "temperature-sensitivity". This feature is of great significance to their application of catalyzing reaction or extraction process, and makes the recovery and reuse of ionic liquids(ILs) become easier. Moreover, the experimental solubility data were correlated with the modified Apelblat equation and λh equation, respectively. It was found that the result of correlation using two divided tem-perature ranges was better than that of using the whole temperature range. 展开更多
关键词 ionic liquids benzothiazolium ALKANOL SOLUBILITY temperature-sensitivity correlation
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