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基于群体智能挖掘的个性化商品评论呈现方法

浙江大学学报（工学版） 2017年第4期51卷 675-681页

作者：景瑶郭斌王柱於志文周兴社西北工业大学计算机学院陕西西安710129

为了研究基于群体智能挖掘的个性化商品评论呈现方法,以大众点评用户评论为研究对象,对大众点评中的用户评论进行特征提取,并发现兴趣相似的用户.特别是提出基于情感特征和主题分布特征的相似群体发现方法,通过提取用户历史评论的情感... 详细信息

为了研究基于群体智能挖掘的个性化商品评论呈现方法,以大众点评用户评论为研究对象,对大众点评中的用户评论进行特征提取,并发现兴趣相似的用户.特别是提出基于情感特征和主题分布特征的相似群体发现方法,通过提取用户历史评论的情感特征和主题分布特征,刻画用户之间情感和主题的相似度,并发现兴趣相似的用户群体,实现个性化评论呈现.实验结果表明,采用提出的方法可以体现用户间兴趣的相似性并发现与用户有相似兴趣的群体,向用户个性化呈现评论.

关键词：大众点评情感特征主题建模相似度个性化

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基于(0,1)区间的可比排序分析法

数学的实践与认识 2017年第4期47卷 157-162页

作者：佘潇姚泽清解放军理工大学理学院江苏南京211101 西北核技术研究所陕西西安710024

针对传统排序方法未考虑评价者人数及被评价对象个数多少对指标权重排序的影响的不足,提出了基于(0,1)区间的排序分析方法.采用方法构造的评价函数模型,在考虑了评价者和被评价对象这两个因素同时,还能将不同评价系统中的被评价对象放... 详细信息

针对传统排序方法未考虑评价者人数及被评价对象个数多少对指标权重排序的影响的不足,提出了基于(0,1)区间的排序分析方法.采用方法构造的评价函数模型,在考虑了评价者和被评价对象这两个因素同时,还能将不同评价系统中的被评价对象放在一起进行排序比较.由于方法具有对称性和中心化的良好性质,这使得排序更加科学合理,符合人们的直观认识.

关键词：可比排序对称性中心化指标权重

N-二(苯-二氨基甲酰基)甲基磷酸及其铕(Ⅲ)配合物的合成及在DNA电化学传感器中的应用

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中国稀土学报 2014年第5期32卷 595-603页

作者：佘文洁刘伟张瑶杨天林宁夏大学化学化工学院能源化工重点实验室宁夏银川750021

合成了一种新的含磷有机三足体衍生物N-二(苯-二氨基甲酰基)甲基磷酸及其铕(Ⅲ)配合物,通过元素分析、红外光谱、差热-热重等方法对其进行结构表征和组成分析,并以该配合物为杂交探针,对其电化学传感器进行较为系统的研究。结果表明:此... 详细信息

合成了一种新的含磷有机三足体衍生物N-二(苯-二氨基甲酰基)甲基磷酸及其铕(Ⅲ)配合物,通过元素分析、红外光谱、差热-热重等方法对其进行结构表征和组成分析,并以该配合物为杂交探针,对其电化学传感器进行较为系统的研究。结果表明:此配体与Eu(Ⅲ)离子倾向于形成1∶1型配合物;紫外光谱法和循环伏安法的研究结果显示,铕(Ⅲ)配合物与DNA以插入形式发生相互作用。将该配合物作为杂交探针进行DNA电化学传感器研究时发现,该配合物在修饰单链DNA的电极检测作用下,无明显的电化学信号响应。而当将其用于检测杂交双链DNA时,出现了明显信号。基于该配合物的DNA传感器对互补序列、错配序列及非互补序列有良好的选择作用。

关键词：稀土配合物插入模式杂交探针

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基于AR模型的共轭循环波达方向估计

系统工程与电子技术 2006年第2期28卷 171-174页

作者：贾维敏姚敏立宋建社第二炮兵工程学院陕西西安710025

基于信号循环特征的DoA估计都需要确定循环相关函数的最优延迟时间参数,当相同循环频率的多个信号具有不同的最优延迟参数时,利用确定的延迟时间参数很难确定所有信号的DoA估计。利用信号的共轭循环平稳特性,采用基于AR模型的空间谱估... 详细信息

基于信号循环特征的DoA估计都需要确定循环相关函数的最优延迟时间参数,当相同循环频率的多个信号具有不同的最优延迟参数时,利用确定的延迟时间参数很难确定所有信号的DoA估计。利用信号的共轭循环平稳特性,采用基于AR模型的空间谱估计来确定信号的DoA估计,提高了有限长阵列孔径空间分辨率,且该方法不需要选择最优延迟时间参数,从而适用于任何调制类型信号的DoA估计。

关键词：共轭循环平稳特性 AR模型 DoA估计

脂肪醇甲酸酯类酞菁铜配合物的合成、表征及荧光性能

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光谱学与光谱分析 2007年第4期27卷 773-776页

作者：张良徐庆锋路建美姚社春苏州大学化学化工学院江苏省有机化学重点实验室江苏苏州215006

报道了四甲酰氯酞菁铜的合成及其与反应得到正丁醇、正戊醇、正己醇、正辛醇、正十二醇5个含脂肪链取代基的酞菁铜衍生物。分别用红外光谱、紫外-可见光谱、元素分析、核磁共振氢谱等方法对这些衍生物进行了结构和取代度的表征,并研究... 详细信息

报道了四甲酰氯酞菁铜的合成及其与反应得到正丁醇、正戊醇、正己醇、正辛醇、正十二醇5个含脂肪链取代基的酞菁铜衍生物。分别用红外光谱、紫外-可见光谱、元素分析、核磁共振氢谱等方法对这些衍生物进行了结构和取代度的表征,并研究了该系列酞菁铜衍生物在有机溶剂中的溶解性及荧光性能与浓度、取代基的关系。研究结果表明在一般有机溶剂中这些酞菁铜衍生物的溶解性显著提高,荧光强度不随浓度的变化而线性变化、长链要高于短链取代酞菁铜衍生物的荧光强度。

关键词：酞菁铜配合物溶解性荧光

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核壳结构偶氮聚合物的全光开关效应研究

中国激光 2005年第12期32卷 1636-1640页

作者：罗锻斌佘卫龙吴水珠曾钫姚胜兰华东理工大学理学院物理系上海200237 中山大学光电材料与技术国家重点实验室广东广州510275 华南理工大学高分子材料科学与工程系广东广州510640

分别用主客掺杂法和种子乳液聚合法制备了含相同浓度偶氮染料分散红4-(2-hydroxyethyl)ethylamino-2-chloro-4-nitroazobenzene(Disperse Red 13,DR13)的聚甲基丙烯酸甲酯poly(methyl methacrylate)(PMMA)均匀薄膜样品。用经斩波器调制的线偏振氩离子激光(514 nm,CW)作用于样品产生光致双折射。作为探测光的线偏振氦氖激光(633 nm,CW)经过样品,通过与原来偏振方向垂直的检偏器的透射光强强度的调制,实现了光控光的全光开关效应。研究比较了两种样品在控制不同光功率下的光致双折射效应和全光开关效应,比较发现用种子乳液聚合法制备的具有核壳结构的样品在控制光功率、开关时间及开关调制深度等方面均优于主客掺杂样品。

关键词：非线性光学全光开关光致双折射效应偶氮化合物核壳结构

Microvolt T-wave alternans complemented with electrophysiologic study for prediction of ventricular tachyarrhythmias in patients with arrhythmogenic right ventricular cardiomyopathy: a long-term follow-up study

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Chinese Medical Journal 2019年第12期132卷 1406-1413页

作者： she-Liang Xue Xiao-Feng Hou Kang-Yun Sun yao Wang Zhi-Yong Qian Quan-Peng Wang Si-Peng shen Hong-Li Yin Rong Zhang Hai-Ping Yin Jian-Gang Zou Department of Cardiology The First Affiliated Hospital of Nanjing Medical UniversityNanjingJiangsu 210029China Department of Cardiology The Affiliated Wujin Hospital of Jiangsu UniversityChangzhouJiangsu 213002China Department of Cardiology The Affiliated Suzhou Hospital of Nanjing Medical UniversitySuzhouJiangsu 215008China Department of Biostatistics School of Public HealthNanjing Medical UniversityNanjingJiangsu 211166China Key Laboratory of Targeted Intervention in Cardiovascular Disease Collaborative Inn ovation Center for Cardiovascular Disease Translational MedicineNanjing Medical University NanjingJiangsu 211166China

Background: The long-term predicted value of microvolt T-wave alternans (MTWA) for ventricular tachyarrhythmia in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) remains unclear. Our study explored the characteristics of MTWA and its prognostic value when combined with an electrophysiologic study (EPS) in patients with ARVC. Methods: All patients underwent non-invasive MTWA examination with modified moving average (MMA) analysis and an EPS. A positive event was defined as the first occurrence of sudden cardiac death, documented sustained ventricular tachycardia (VT), ventricular fibrillation, or the administration of appropriate implantable cardioverter defibrillator therapy including shock or antitachycardia pacing. Results: Thirty-five patients with ARVC (age 38.6 ± 11.0 years;28 males) with preserved left ventricular (LV) function were recruited. The maximal TWA value (MaxValt) was 17.0 (11.0–27.0)μV. Sustained VT was induced in 22 patients by the EPS. During a median follow-up of 99.9 ± 7.7 months, 15 patients had positive clinical events. When inducible VT was combined with the MaxValt, the area under the curve improved from 0.739 to 0.797. The receiver operating characteristic curve showed that a MaxValt of 23.5 μV was the optimal cutoff value to identify positive events. The multivariate Cox regression model for survival showed that MTWA (MaxValt, hazard ratio [HR], 1.06;95% confidence interval [CI], 1.01–1.11;P = 0.01) and inducible VT (HR, 5.98;95% CI, 1.33–26.8;P = 0.01) independently predicted positive events in patients with ARVC. Conclusions: MTWA assessment with MMA analysis complemented by an EPS might provide improved prognostic ability in patients with ARVC with preserved LV function during long-term follow-up.

关键词： Modified moving average analysis Microvolt T-wave alternans Electrophysiologic study Ventricular tachyarrhythmia Arrhythmogenic right ventricular cardiomyopathy

Hemorrhagic blisters in fulminant Aeromonas hydrophila bacteremia: Case report and literature review

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Asian Pacific Journal of Tropical Medicine 2019年第2期12卷 91-94页

作者： yao-Tien Chang Sung-Yuan Hu Che-An Tsai Department of Emergency Medicine Taichung Veterans General Hospital Department of Nursing College of Health National Taichung University of Science and Technology School of Medicine Chung Shan Medical University Institute of Medicine Chung Shan Medical University Department of Nursing College of Nursing Central Taiwan University of Science and Technology Division of Infectious Disease Department of Internal Medicine Taichung Veterans General Hospital

The Aeromonas species, belonging to the family Aeromonadaceae, are opportunistic pathogens found in humans with an incidence rate of 76 cases per million inhabitants in Southern *** incidence of Aeromonas septicemia is relatively low, accounting for less than 15% of *** diagnosed with Aeromonas hydrophila bacteremia who were presented with skin blisters and septic shock have been reported to have a mortality rate of 100%.Aeromonas infection must be considered in the differential diagnosis of gangrene-like tissue damage or skin lesions in patients with end-stage renal disease, due to the potential sources of infections.A 49-year-old Taiwan Residents diabetic woman with end-stage renal disease had underwent regular *** was referred to our hospital due to a one-day course of fever, dyspnea, hypotension, and fulminant hemorrhagic blisters covering her whole body.A physical examination uncovered multiple hemorrhagic blisters, along with a ruptured blister over the lower left *** tests revealed an elevation of liver enzymes, impaired renal function, lactatemia, and high anion-gap metabolic *** of both blood and hemorrhagic blister fluid grew Aeromonas ***, she experienced persistent shock despite aggressive intravenous fluid, empiric antibiotics, and inotropic agents with norepinephrine and *** diagnosis and prompt management using intravenous fluids, antibiotics and surgical debridement is recommended in order to improve a patient's survival rate.

关键词： Aeromonas hydrophila Bacteremia End-stage renal disease Hemorrhagic blister

Intense blue-emitting Ca_2PO_4Cl:Eu^(2+) phosphor for near-ultraviolet converting white light-emitting diodes

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Journal of Rare Earths 2010年第S1期28卷 250-253页

作者： Yi-Chen Chiu Chun-Kuei Chang yao-Tsung Yeh Shyue-Ming Jang Material and Chemical Research Laboratories Industrial Technology Research Institute Phosphors Research Laboratory and Department of Applied Chemistry National Chiao Tung University

A blue phosphor Ca2PO4Cl:Eu2+(CAP:Eu2+) was synthesized by solid state *** Ca2PO4Cl:Eu2+ exhibited high quantum efficiency and excellent thermal *** luminescent intensity of Ca2PO4Cl:Eu2+ was found to be 128% under excitation at 380 nm,149% under 400 nm,and 247% under 420 nm as high as that of BaMgAl10O17:Eu2+.The optimal doping concentration was observed to 11 mol.% of CAP:Eu2+.The energy transfer between Eu2+ ions in CAP were occurred via electric multipolar interaction,and the critical transfer distance was estimated to be 1.26 nm.A mixture of blue-emitting Ca2PO4Cl:Eu2+,green-emitting(Ba,Sr)2SiO4:Eu2+ and red-emitting CaAlSiN3:Eu2+ phosphors were selected in conjunction with 400 nm chip to fabricate white LED *** average color-rendering index Ra and correlated color temperature(Tc) of the white LEDs were found to be 93.4 and 4590 K,*** results indicated that it was a promising candidate as a blue-emitting phosphor for the near-UV white light-emitting diodes.

关键词： Ca2PO4Cl:Eu2+ phosphors luminscense rare earths