基于Single-Pass的网络舆情热点发现算法

考虑网络事件的时间距离,基于半结构化网页中不同位置特征项重要程度的不同,提出改进的single-pass文本聚类算法single-pass*,优势在于对Web文本不同位置特征项的加权处理,仅需计算新文档与同类别种子文档间的相似度。实验结果表明,相比single-pass,改进算法极大减少了漏检率和错检率,降低了由于新文本流内文档进行相似度计算导致系统性能的下降,平均提高Web文本聚类效率40%。将聚类后的Web文本应用于网络舆情分析,进行主题关注度分析和话题热度特性分析。

基于Single-Pass的在线话题检测改进算法

现有话题检测的主要方法是利用Single-Pass及其改进算法进行聚类分析,没有考虑文本的结构特点,相似度计算方法单一,从而影响准确度.针对此问题,改进了Single-Pass的相似度计算方法,综合考虑文本的标题、摘要、时间、地名以及来源等要素,采用层次分析法计算并赋以不同权重,提出一种多相似度计算组合策略.考虑到食品安全是一个广受关注的话题,实验通过网络爬虫抓取并筛选了最近3年食品安全方面的媒体信息,以此作为数据进行分析,结果表明,采用本文提出的改进Single-Pass聚类算法,话题检测准确度更高.

基于多特征融合Single-Pass-SOM组合模型的话题检测

当今时代,网络舆情传播速度快、影响力大,而话题检测在网络舆情监管中有着不可替代的作用.针对传统方法提取文本特征不完整和特征维度过高的问题,本文提出了基于时间衰减因子的LDA&&Word2Vec文本表示模型,将LDA模型的隐含主题特征和Word2Vec模型的语义特征进行加权融合,并引入了时间衰减因子,同时起到了降维和提高文本特征完整度的作用.同时,本文又提出了Single-Pass-SOM组合聚类模型,该模型解决了SOM模型需要设定初始神经元的问题,提高了话题聚类的精度.实验结果表明,本文提出的文本表示模型和文本聚类方法较传统方法拥有更好的话题检测效果.

基于改进Single-Pass算法的BBS热点话题发现

详细介绍了经典增量式聚类算法Single-Pass的特点,针对该算法中"聚类质心不唯一"的缺陷提出"设定唯一聚类质心"的改进方案,降低了算法的时间复杂度;针对"算法聚类中心随机性强"的不足提出了"不断优化聚类中心"的改进方案,使得聚类中心的代表性更强.最后,基于"中华网BBS"文本数据对改进后的算法进行验证、分析,并与经典Single-Pass算法的聚类结果进行对比,得到了更为理想的实验结果,表明算法可行有效.

基于改进的single-pass网络舆情话题发现研究

舆情监控系统解决的关键问题是如何有效且精确地对文本进行聚类,以便从大量Web网页中发现网络舆情热点话题。single-pass算法是话题发现中最常用的文本聚类算法,但其在文本聚类的精度和时效方面存在不足,因而论文在对大量新闻报道语料进行深入分析的基础上,从三个方面对single-pass进行了改进。通过实验求证,发现改进后的single-pass算法在漏检率、误检率和耗费函数等方面有了明显改善。

基于自编码神经网络的Single-Pass聚类事件识别算法

针对传统Single-Pass聚类算法存在的缺陷,提出了一种基于自编码神经网络的Single-Pass聚类算法。通过多个深层的隐藏层对原始数据进行降维,以更好地提取出原始数据的特征信息;并通过对边缘文本重计算来降低误检率,提高聚类精度。实验结果表明,该算法相比传统Single-Pass算法具有更高的聚类准确度,解决了聚类结果受数据顺序影响的问题。

Intestinal permeability of metformin using single-pass intestinal perfusion in rats

AIM： To characterize the intestinal transport and mechanism of metformin in rats and to investigate whether or not metformin is a substrate for P-glycoprotein （P-gp）. METHODS： The effective intestinal permeability of metformin was investigated using single-pass intestinal perfusion （SPIP） technique in male Waster rats. SPIP was performed in three isolated intestinal segments （duodenum, jejunum and ileum） at the same concentration of metformin （50 μg/mL） to test if the intestinal transport of metformin exhibited site- dependent changes, and in a same isolated intestinal segment （duodenal segment） at three different concentrations of metformin （10, 50, 200 μg/mL） to test if the intestinal transport of metformin exhibited concentration-dependent changes. Besides, P-gp inhibitor verapamil （400 μg/mL） was co-perfused with metformin （50 μg/mL） in the duodenum segment to find out if the intestinal absorption of metformin was affected by P-gp exiting along the gastrointestinal track. Stability studies were conducted to ensure that the loss of metformin could be attributed to intestinal absorption. RESULTS： The effective permeability values （Peff） of metformin in the jejunum and ileum at 50μg/mL were significantly lower than those in the duodenum at the same concentration. Besides, Peff values in the duodenum at high concentration （200 μg/mL） were found to be significantly lower than those at low and medium concentrations （10 and 50 μg/mL）. Moreover the coperfusion with verapamil did not increase the Peff value of metformin at 50 μg/mL in the duodenum.CONCLUSION： Metformin could be absorbed from the whole intestine, with the main absorption site at duodenum. This concentration-dependent permeability behavior in the duodenum indicates that metformin is transported by both passive and active carrier-mediated saturable mechanism. The Peff value can not be increased by co-perfusion with verapamil, indicating that absorption of metformin is not efficiently transported by P-gp in the gut wall. Furthermore metformin is neither a substrate nor an inducer of P-gp. Based on the Peff values obtained in the present study and using established relationships, the human fraction dose absorbed for metformin is estimated to be 74%-90% along human intestine.

基于Single-Pass算法的网络舆情文本增量聚类算法研究

随着信息技术的快速发展,互联网成为主要社会信息传播方式,网络舆情的影响力不断扩大。网络舆情具有内容丰富、信息量大且相关话题种类繁多等特点,虽然聚类技术可以用来发现网民关注的话题,但是传统聚类算法还无法直接应用于海量动态网络舆情监控。本文根据网络舆情动态演化特点,研究高效的增量文本聚类算法,选取经典的增量聚类算法Single-Pass进行了改进,解决了该算法输入数据顺序敏感问题及求解效率问题。实验结果表明,在海量舆情文本聚类过程中,该方法可以大大提升舆情文本聚类效率,同时聚类精度未受到影响。

基于改进的Single-Pass算法微博话题发现

详细介绍传统的Single-Pass算法并分析它的特点和不足之处,并针对传统的Single-Pass算法对输入顺序敏感的问题,提出一种改进方法,即找出含有话题信息丰富的微博客文本优先聚类,得到初始的话题簇,再对余下的微博客文本进行聚类以提高聚类的精度。对话题发现的流程:文本预处理、向量模型的构建、Single-Pass聚类、凝聚层次聚类进行详细的描述,实验结果表明该方法在召回率、准确率、F值指标上均优于传统的方法。

Hierarchical clustering based on single-pass for breaking topic detection and tracking

Single-pass is commonly used in topic detection and tracking( TDT) due to its simplicity,high efficiency and low cost. When dealing with large-scale data,time cost will increase sharply and clustering performance will be affected greatly. Aiming at this problem,hierarchical clustering algorithm based on single-pass is proposed,which is inspired by hierarchical and concurrent ideas to divide clustering process into three stages. News reports are classified into different categories firstly.Then there are twice single-pass clustering processes in the same category,and one agglomerative clustering among different categories. In addition,for semantic similarity in news reports,topic model is improved based on named entities. Experimental results show that the proposed method can effectively accelerate the process as well as improve the performance.

基于改进Single-Pass的新闻话题检测与追踪技术研究

为解决如何从海量新闻报道中检测并追踪到目标话题,选择了自增式聚类Single-Pass算法进行研究.在原有的基础上对其进行改进得到改进后的Single-Pass聚类算法,期望能得到更好的解决方法.对于原有算法进行的改进主要有在新闻文本的特征词选取中加入权重系数表达特征词位置信息,同时辅以时间特征进行新闻文本相似度计算,并且在Single-Pass聚类算法步骤中添加子话题阈值判断过程.实验验证改进后的Single-Pass聚类算法不仅可得到不同粒度的话题聚类效果,同时也提升了聚类效率.实验结果证明,在相同条件下,改进后的Single-Pass聚类算法在漏检率和误检率上有明显的改善.

基于改进Single-pass 算法的新闻话题演化跟踪算法

随着信息技术的发展,每天都有大量的新闻文本在互联网上发布、转发,在这样的海量信息环境下,如何快速定位自己感兴趣的话题、追踪其发展趋势已成了近年来的研究热点。面向互联网上新闻文本,提出聚类阈值的估计方法对已有的Single-pass算法进行优化,进而基于时间片设计一个新闻文本演化算法。在新华网等四个网站上采集新闻数据并进行实验,实验表明所提算法可有效跟踪新闻话题的演化过程。

A review on single-pass grinding processes

The most important grinding processes were realized in a single pass of the grinding wheel,such as continuous path controlled grinding (CPCG/Peelgrinding/HSP),CPCG with reduced contact of the grinding wheel (Quickpoint),single-pass longitudinal internal grinding,creep feed grinding (CFG),longitudinal cylindrical grinding with grinding wheels made of conventional abrasive materials and longitudinal internal cylindrical grinding using grinding wheels with zone-diversified structure.

Absorption characteristic of Paeoniflorin-6＇O-benzene sulfonate in an situ single-pass intestinal perfusion model

Aim Paeoniflorin-6＇O-benzene sulfonate （CP-25） was synthesized to improve oral absorption. This study was performed to investigate absorptive behavior and mechanism of CP-25 in intestine. Methods The effects of drug concentration, intestinal segments, gender as well as ATP binding cassette （ABC） transporter inhibitors on absorption of CP-25 were studied in a situ single-pass intestinal perfusion rat model. Meanwhile, Paeoniflorin （Pae） was tested and served as control group. The concentration of tested drugs was measured by HPLC. Results The results showed intestinal absorption of CP-25 was neither segmental dependent changes nor gender difference. Transepithelial transportation would not change with increasing concentrations of CP-25, which suggest a passive transport was the main pattern of CP-25. Additionally, absorption of CP-25 was much better than that of Pae in small intestine. When compared with Pae, CP-25 gave a 1.82-fold permeability rate. Finally, the results indicated Pae was substrate of P-glycoprotein （P-gp） , but was not the substrate of breast cancer resistance protein and muhi- drug resistance associated protein 2. Among the used ABC inhibitors, the absorption rate of Pae could only be in- creased by？ P-gp inhibitor Verapamil and GF120918, while CP-25 had no remarkable alteration. Conclusion CP-25 has better absorptive features than that of Pae, which may be attributed to its lipophicity enhancement and be unaffected by P-gp efflux.

Successful Management of Sickle Cell Intrahepatic Cholestasis with Combined Use of Exchange Transfusion and Single-Pass Albumin Dialysis: A Case Report

Sickle-cell intrahepatic cholestasis (SCIC) is an uncommon complication of sickle-cell disease (SCD), which can be life-threating if left untreated. We present the case of a 28-year-old man with SCD, who presented with jaundice and abdominal pain, one month after hydroxyurea discontinuation. Laboratory investigation revealed solely increased serum bilirubin, mainly conjugated, and imaging studies revealed choledocholithiasis. The patient unterwent an endoscopic sphincterectomy, but his jaundice deteriorated. Sickle-cell intrahepatic cholestasis was suspected and he received aggressive exchange transfusion therapy in combination with hydroxyurea. The jaundice had no signs of improvement;in fact total bilirubin raised up to 1053.7 μmol/L (61.62 mg/dl). Subsequently, the patient was treated with single-pass albumin dialysis (SPAD), in order to remove the excess bilirubin and protect mainly the brain and liver cells from its toxic effects. His laboratory values started to improve after one-and-a-half months of treatment. For the next two months, exchange transfusions were continued and bilirubin gradually returned to baseline values. The successful response appeared after the combined use of exchange transfusion and SPAD, which is being reported for the first time.

EFI Reggiani: Innovation trendsetting with the game-changing single-pass digital printer

Electronics For Imaging, Inc.(Nasdaq: EFII) showcased the advanced, leading-edge technologies that make EFI? Reggiani a textile innovator at ITMA 2019, June 20th - 26th in Barcelona, including the gamechanging EFI Reggiani BOLT single-pass inkjet printer – the first digital textile solution capable of high-quality output at record production speeds of up to 90 linear meters (295 linear feet) per minute.

智能化集中式Single-Pass问世

近期,深圳市润天智数字设备股份有限公司（证券代码：832246）为加快推进37000平方米智能化数字纺织印花设备生产基地的建设,在新三板公开发行股票募集资金1455万元。建成后,将成为世界最大的喷墨印刷设备制造基地。经过十六年的发展,润天智凭借创新和技术实力,获得多项自主知识产权,百项发明专利,是享誉国际的行业龙头。并先后建立了喷墨印刷设备机械加工基地、钣金加工基地和组装测试基地以及印刷墨水生产基地。产品更是覆盖世界六大洲80多个国家或地区,

Effect of deformation parameters on the austenite dynamic recrystallization behavior of a eutectoid pearlite rail steel

Understandings of the effect of hot deformation parameters close to the practical production line on grain refinement are crucial for enhancing both the strength and toughness of future rail steels.In this work,the austenite dynamic recrystallization(DRX)behaviors of a eutectoid pearlite rail steel were studied using a thermo-mechanical simulator with hot deformation parameters frequently employed in rail production lines.The single-pass hot deformation results reveal that the prior austenite grain sizes(PAGSs)for samples with different deformation reductions decrease initially with an increase in deformation temperature.However,once the deformation temperature is beyond a certain threshold,the PAGSs start to increase.It can be attributed to the rise in DRX volume fraction and the increase of DRX grain with deformation temperature,respectively.Three-pass hot deformation results show that the accumulated strain generated in the first and second deformation passes can increase the extent of DRX.In the case of complete DRX,PAGS is predominantly determined by the deformation temperature of the final pass.It suggests a strategic approach during industrial production where part of the deformation reduction in low temperature range can be shifted to the medium temperature range to release rolling mill loads.

Simulation of ion cyclotron wave heating in the EXL-50U spherical tokamak based on dispersion relations

This study investigates the single-pass absorption(SPA) of ion cyclotron range of frequency(ICRF) heating in hydrogen plasma of the EXL-50U spherical tokamak,which is an upgraded EXL-50 device with a central solenoid and a stronger magnetic field.The reliability of the kinetic dispersion equation is confirmed by the one-dimensional full-wave code,and the applicability of Porkolab's simplified theoretical SPA model is discussed based on the kinetic dispersion equation.Simulations are conducted to investigate the heating effects of the fundamental and second harmonic frequencies.The results indicate that with the design parameters of the EXL-50U device,the SPA for second harmonic heating is 63%,while the SPA for fundamental heating is 13%.Additionally,the optimal injection frequencies are 23 MHz at 0.9 T and 31 MHz at 1.2 T.The wave vector of the antenna parallel to the magnetic field,with a value of k_‖=7.5 m^(-1),falls within the optimal heating region.Simulations reveal that the ICRF heating system can play an important role in the ion heating of the EXL-50U.

基于人工智能的高校反电信网络诈骗模型研究

近年来,电信网络诈骗日益猖獗,导致许多高校师生遭遇网络诈骗,因此急需开发出一套高效的检测模型,专注于辨识诈骗类网站。该模型结合了网站结构与文本分析,运用了网页指纹、TextRank、Single-pass、BERT、TextCNN和FastText算法,实现了对诈骗网站的精确识别。该方法提升了检测的准确率,加强了校园师生财产的安全防护,展现了积极预防的重要性,对电信诈骗防范具有显著的应用价值。