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基于非参数统计的不平衡数据混合抽样算法研究

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基于非参数统计的不平衡数据混合抽样算法研究

作者：曹倩华北理工大学

学位级别：硕士

如今对不平衡数据的研究已有较多的成果,大多数专家学者都集中在算法层面上,在数据层面研究较少且对欠抽样的研究较多,过抽样的研究较少。大数据时代不仅仅需要欠抽样,过抽样同样重要。针对上述问题,对利用Topsis方法选择数据集多数类... 详细信息

如今对不平衡数据的研究已有较多的成果,大多数专家学者都集中在算法层面上,在数据层面研究较少且对欠抽样的研究较多,过抽样的研究较少。大数据时代不仅仅需要欠抽样,过抽样同样重要。针对上述问题,对利用Topsis方法选择数据集多数类的“理想”样本,通过计算与理想样本的贴近度进行欠抽样达到数据平衡、利用非参数的Walsh平均方法进行过抽样达到数据平衡、利用Topsis欠抽样方法与Walsh平均过抽样方法进行欠过融合的混合抽样达到数据平衡的三种抽样算法进行研究。最后,对三种消除数据不平衡方法进行比较,探讨各自适合的数据集的不平衡度。主要研究内容及所得结论如下:1)利用Topsis方法选择数据集多数类的“理想”样本,选择与理想样本贴近度低的样本进行欠抽样以达到数据平衡,对平衡数据进行Logistic回归分析,所得结果的分类精确性评判指标AUC值为0.929,明显高于基于原样本、Easy Ensemble欠抽样、SMOTE过抽样三种模型所得AUC值。2)利用非参数的Walsh平均方法进行过抽样达到数据平衡,对平衡数据进行Logistic回归分析,所得结果的分类精确性评判指标AUC值为0.859,高于基于原样本、Easy Ensemble欠抽样、SMOTE过抽样三种模型所得AUC值。3)使用Topsis欠抽样方法与Walsh平均过抽样方法进行欠过融合的混合抽样达到数据平衡,对平衡数据进行Logistic回归分析,所得结果的分类精确性评判指标AUC值为0.880,高于基于原样本、Easy Ensemble欠抽样、SMOTE过抽样三种模型所得AUC值。4)Topsis、Walsh混合抽样方法适用于十级样本差数据、百级样本差数据;Topsis欠抽样方法适用于千级样本差数据以及万级样本差数据。图28幅;表50个;参45篇。

关键词： Topsis欠抽样 Walsh平均过抽样混合抽样平衡数据不平衡度

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舰船通信系统非平衡数据多目标自动检测技术

舰船科学技术 2018年第12X期40卷 127-129页

作者：王玉华呼伦贝尔职业技术学院内蒙古呼伦贝尔021000

传统舰船通信系统非平衡数据检测技术需要计算所有数据,检测效率低下。对此设计舰船通信系统非平衡数据多目标自动检测技术。通过计算通信数据集内各数据点的欧几里德距离,剔除带有明显维度特征的非平衡数据减少计算量,将剩余通信数据... 详细信息

传统舰船通信系统非平衡数据检测技术需要计算所有数据,检测效率低下。对此设计舰船通信系统非平衡数据多目标自动检测技术。通过计算通信数据集内各数据点的欧几里德距离,剔除带有明显维度特征的非平衡数据减少计算量,将剩余通信数据降维并建立一维空间映射,最后对空间映射内的一维数据集特异值进行统计计算,实现非平衡数据检测。实验研究表明相比较传统检测方式,单位时间下设计的多维数据异常点检测数量高25%,固定异常点数据用时缩减23%,可以明显提高检测效率。

关键词：通信系统平衡数据自动检测

EQUILIBRIUM DATA OF CYCLOPENTANE HYDRATE

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化工学报 2001年第9期52卷 753-754页

作者：梁德青郭开华樊栓狮王如竹上海交通大学上海 200030 中科院广州能源所广东广州 510070

Ｉｎｔｈｅｏｉｌａｎｄｇａｓｉｎｄｕｓｔｒｙ ,ｉｔｉｓｉｍｐｏｒｔａｎｔｔｏｄｅｔｅｒｍｉｎｅｈｙｄｒａｔｅｐｈａｓｅｂｏｕｎｄａｒｙｆｏｒａｖｏｉｄｉｎｇｈｙｄｒａｔｅｆｏｒｍａｔｉｏｎ .Ｉｎｇｅｎｅｒａｌｎ -ｂ... 详细信息

Ｉｎｔｈｅｏｉｌａｎｄｇａｓｉｎｄｕｓｔｒｙ ,ｉｔｉｓｉｍｐｏｒｔａｎｔｔｏｄｅｔｅｒｍｉｎｅｈｙｄｒａｔｅｐｈａｓｅｂｏｕｎｄａｒｙｆｏｒａｖｏｉｄｉｎｇｈｙｄｒａｔｅｆｏｒｍａｔｉｏｎ .Ｉｎｇｅｎｅｒａｌｎ -ｂｕｔａｎｅｉｓｒｅｇａｒｄｅｄａｓｔｈｅｈｅａｖｉｅｓｔｈｙｄｒｏｃａｒｂｏｎｈｙｄｒａｔｅ .Ｂｕｔｆｏｒｏｉｌａｎｄｇａｓｃｏｎｄｅｎｓａｔｅｓｙｓｔｅｍｓ ,ｉｔｈａｓｂｅｅｎｆｏｕｎｄｔｈａｔｓｏｍｅｈｙｄｒｏｃａｒｂｏｎｓｈｅａｖｉｅｒｔｈａｎｎ -ｂｕｔａｎｅｃｏｕｌｄｅｎｔｅｒｔｈｅｌａｒｇｅｃａｖｉｔｙｏｆｓｔｒｕｃｔｕｒｅ -ＩＩｈｙｄｒａｔｅｄｕｅｔｏｔ

关键词：环茂烷水合物平衡数据物相变化

萃取精馏法生产均三甲苯的平衡数据测定及模拟

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河南化工 2006年第3期23卷 37-39页

作者：杨胜凯郑芳杨凤霞汤波河南科技学院化工系河南新乡453003 中原油田石油化工总厂河南濮阳457165

以邻苯二甲酸二丁酯(DBP)为萃取精馏溶剂,测定了邻甲乙苯—均三甲苯—偏三甲苯体系的二元及三元汽液平衡数据;编程关联了W ilson模型参数;采用物料平衡三对角矩阵法对萃取精馏过程进行了模拟,得出了萃取精馏塔的最佳操作条件,为萃取精... 详细信息

以邻苯二甲酸二丁酯(DBP)为萃取精馏溶剂,测定了邻甲乙苯—均三甲苯—偏三甲苯体系的二元及三元汽液平衡数据;编程关联了W ilson模型参数;采用物料平衡三对角矩阵法对萃取精馏过程进行了模拟,得出了萃取精馏塔的最佳操作条件,为萃取精馏法生产均三甲苯提供了基础数据。

关键词：萃取精馏邻苯二甲酸二丁酯均三甲苯平衡数据模拟

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超临界二氧化碳萃取姜油平衡数据的测定

福州大学学报（自然科学版） 2000年第1期28卷 87-90页

作者：臧志清周晓东周端美福州大学化学工程系福建福州350002

建立了一套静止法测定固态物质在超临界ＣＯ２中溶解度的装置．测定了姜油在超临界ＣＯ２中的溶解度．把姜油按化合物类别分为四类组分；拟合了三类组分的溶解度与ＣＯ２密度、温度的关联经验式，这些关联式为超临界ＣＯ２萃取和分离操... 详细信息

建立了一套静止法测定固态物质在超临界ＣＯ２中溶解度的装置．测定了姜油在超临界ＣＯ２中的溶解度．把姜油按化合物类别分为四类组分；拟合了三类组分的溶解度与ＣＯ２密度、温度的关联经验式，这些关联式为超临界ＣＯ２萃取和分离操作的技术分析提供依据．

关键词：生姜姜油萃取平衡数据

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环己醇─环己酮汽液平衡数据测定及关联

辽阳石油化工高等专科学校学报 2000年第3期16卷 1-4页

作者：虞琦辽阳石油化工高等专科学校化工系辽阳111003

采用改进的Rose汽液平衡釜 ,测定了环己醇─环己酮二元体系在 8665Pa和6664Pa下的汽液平衡数据 ,并用WILSON方程和UNIQUAC方程对所测数据进行关联 ,获得了方程参数。

关键词：环己醇环己酮汽液平衡平衡数据二元体系

Density,refractive index and liquid–liquid equilibrium data of polyethylene glycol 3000 + potassium formate + water at different pH values

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Chinese Journal of Chemical Engineering 2018年第1期26卷 168-174页

作者： Fatemeh Ahmadi Mohsen Pirdashti Abbas Ali Rostami Chemical Engineering Department Faculty of EngineeringShomal University

New liquid–liquid equilibrium data for polyethylene glycol(PEG) 3000 + CHO_2K + H_2O systems were measured at 298.15 K and pH values of 7.95, 8.40 and 9.98. It was found that an increase in pH caused the binodal curve to be displaced downward and the two-phase region to expand. Accordingly, the binodal curve was adjusted to the Pirdashti equation and the tie-line compositions were correlated using the Othmer–Tobias, Bancroft and Hand equations. The study measured the refractive index and densities of several homogeneous binary and ternary solutions. The solutions were used for calibration within a range of 0% to 30% of the mass of the PEG and potassium formate. The density and refractive index data show a linear variation with the mass fraction of the polymer and the salt. The effect of pH on the binodal, tie-line lengths(TLL) and slope of the tie-line(STL) in the systems was examined. It was found that an increase in pH increased the TLL and decreased the STL. It was observed that the density of the aqueous two-phase system was influenced by the TLL. The difference in density between phases(Δρ) increased as the TLL and pH increased. It was found that the TLL and Δρ showed a linear relationship. The effective excluded volume(EEV) of the PEG was obtained and it was found that EEV also increased as the pH increased.

关键词：聚乙烯乙二醇平衡数据甲酸盐 pH 密度液体索引折射

Heavy metals adsorption by banana peels micro-powder: Equilibrium modeling by non-linear models

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Chinese Journal of Chemical Engineering 2018年第3期26卷 455-464页

作者： Giorgio Vilardi Luca Di Palma Nicola Verdone Sapienza University of Rome Department of Chemical Engineering Materials Environment

In this study the copper and lead adsorption efficiency onto banana peels powder was investigated. The agroindustrial waste recovery represents one of the Circular Economy pillars. In the view of the synthesis of an environmentally friendly adsorbent material, the powder was used without any preliminary chemical or thermal activation, but only after simple washing, drying and grinding. The bio-adsorbent was characterized by the FTIR technique and tested in batch mode on synthetic aqueous solutions containing Pb and Cu in the range 10–90 mg·L^(-1). A selection of two(Langmuir, Freundlich) and three(Sips, Redlich–Peterson, Koble–Corrigan) parameter isotherm models was chosen to fit adsorption equilibrium data by non-linear regression procedure. The best fit isotherm model was selected relying on the error function with the lowest average percentage error(APE) value, among those characterized by the highest R^2 values. As expected, the three-parameter models are found to better represent both metals bio-adsorption, with APE and R^2 values always lower and higher, respectively, than the corresponding values obtained for the two-parameter models.

关键词：等温线模型重金属吸附平衡数据非线性香蕉皮粉末模特儿吸附效率

Acarbose Isolation with Gel Type Strong Acid Cation Exchange Resin： Equilibrium, Kinetic and Thermodynamic Studies

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Chinese Journal of Chemical Engineering 2013年第10期21卷 1106-1113页

作者：王亚军于蕾郑裕国王远山沈寅初 Institute Of Bioengineering Zhejiang University of Technology Hangzhou 310014 China Engineering Research Center of Bioconversion and Biopurification Ministry of Education Zhejiang University ofTechnology Hangzhou 310014 China

Acarbose, a potent α-glucosidase inhibitor, is widely used as an oral anti-diabetic drug for the treatment of the type 2, non-insulin-dependent diabetes. In this work, a gel type strong acid cation exchange resin 001×4 was applied to isolate acarbose from fermentation broth. It was demonstrated that cation exchanger 001×4 displayed a large adsorption capacity and quick exchange rate for acarbose. The static adsorption equilibrium data were well fitted to the Langmuir equation. Column adsorption experiments demonstrated that high dynamic adsorption capacity was reached at bed height of 104.4 mm, feed flow rate of 1.0 ml·min 1and acarbose concentration of 4.0 mg·ml 1.Under the optimized conditions, the column chromatography packed with cation exchanger 001×4 recovered 74.3%(by mass) of acarbose from Actinoplanes utahensis ZJB-08196 fermentation broth with purity of 80.1%(by mass),demonstrating great potential in the practical applications in acarbose separation.

关键词：强酸性阳离子交换树脂阿卡波糖平衡数据凝胶型分离 Langmuir方程热力学动力学