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微博客(Micro-blog)在图书馆中的应用研究 被引量:38
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作者 陈丽纳 《四川图书馆学报》 CSSCI 2010年第4期32-36,共5页
文章首先介绍了微博客(Micro-blog)的特性,阐述了微博客在图书馆中应用的意义、可行性、应用机制以及应用领域,并指出了微博客在应用过程中需要注意的问题。
关键词 微博客 图书馆 新浪微博 参考咨询
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On the Linguistic Features of Comments in Micro-blogs from Different Social Status
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作者 许之所 刘云龙 《英语广场(学术研究)》 2012年第9期51-53,共3页
The study makes a contrastive analysis of the differences in the comments of people from different social status in their Mini-blogs.It aims to find the manifestations of those differences by analyzing the underlying ... The study makes a contrastive analysis of the differences in the comments of people from different social status in their Mini-blogs.It aims to find the manifestations of those differences by analyzing the underlying causes and provide constructive suggestions on how to build a more harmonious public platform,which is of its great significance. 展开更多
关键词 micro-blog linguistic feature language variety
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Chinese micro-blog sentiment classification through a novel hybrid learning model 被引量:2
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作者 LI Fang-fang WANG Huan-ting +3 位作者 ZHAO Rong-chang LIU Xi-yao WANG Yan-zhen ZOU Bei-ji 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第10期2322-2330,共9页
With the rising and spreading of micro-blog, the sentiment classification of short texts has become a research hotspot. Some methods have been developed in the past decade. However, since the Chinese and English are d... With the rising and spreading of micro-blog, the sentiment classification of short texts has become a research hotspot. Some methods have been developed in the past decade. However, since the Chinese and English are different in language syntax, semantics and pragmatics, sentiment classification methods that are effective for English twitter may fail on Chinese micro-blog. In addition, the colloquialism and conciseness of short Chinese texts introduces additional challenges to sentiment classification. In this work, a novel hybrid learning model was proposed for sentiment classification of Chinese micro-blogs, which included two stages. In the first stage, emotional scores were calculated over the whole dataset by utilizing an improved Chinese-oriented sentiment dictionary classification method. Data with extremely high or low scores were directly labeled. In the second stage, the remaining data were labeled by using an integrated classification method based on sentiment dictionary, support vector machine(SVM) and k-nearest neighbor(KNN). An improved feature selection method was adopted to enhance the discriminative power of the selected features. The two-stage hybrid framework made the proposed method effective for sentiment classification of Chinese micro-blogs. Experiments on the COAE2014(Chinese Opinion Analysis Evaluation 2014) dataset show that the proposed method outperforms other schemes. 展开更多
关键词 CHINESE micro-blog SHORT TEXT HYBRID LEARNING SENTIMENT classification
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The Simulation of Rumor’S Spreading and Controlling in Micro-Blog Users’ Network 被引量:3
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作者 Peng Chen Nan Gao 《Journal of Software Engineering and Applications》 2013年第3期102-105,共4页
In this work, a rumor’s spreading and controlling in a directed Micro-blog user network being consisted with 580 000 nodes are simulated. By defining some authority nodes that release anti-rumor information as the pr... In this work, a rumor’s spreading and controlling in a directed Micro-blog user network being consisted with 580 000 nodes are simulated. By defining some authority nodes that release anti-rumor information as the prevention strategy, the effect of the nodes’ role in network on rumor’s suppression is studied. The findings show that rumor will be spread out fast and reach a stable level within limited steps. The suppression of rumor is more predominated by the intervening opportunity, the earlier the intervention strategy was implemented, the better the rumor’s controlling could be achieved. The controlling effect is less relevant with the role of the authority nodes in network. 展开更多
关键词 COMPONENT RUMOR micro-blog NETWORK SIMULATION
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A Study on the Evolution of Mechanism of Infectious Disease Analysis Model of Event Using Micro-Blog Platform 被引量:1
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作者 Haiying Ma 《Social Networking》 2015年第3期96-102,共7页
After the occurrence of unexpected group events of network, the relevant opinion information will spread rapidly through micro-blog, and the negative public opinion information will aggravate the unexpected the group ... After the occurrence of unexpected group events of network, the relevant opinion information will spread rapidly through micro-blog, and the negative public opinion information will aggravate the unexpected the group events to upgrade and expand the scope of harm. It is difficult to deal. So public opinion control is very important. In this paper, we establish an influence model for spreading of public opinion based on SIR model. Through the political analysis, this paper finds that the network group events will subside, but the influence scope, time and ability of event cannot be ignored. As a result of this study, the corresponding strategies are put forward in this paper. 展开更多
关键词 micro-blog Group Events of Network PUBLIC OPINION Control SIR Model
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Impact of user influence on information multi-step communication in a micro-blog
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作者 吴越 胡勇 +1 位作者 何小海 邓垦 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第6期5-12,共8页
User influence is generally considered as one of the most critical factors that affect information cascading spreading. Based on this common assumption, this paper proposes a theoretical model to examine user influenc... User influence is generally considered as one of the most critical factors that affect information cascading spreading. Based on this common assumption, this paper proposes a theoretical model to examine user influence on the information multi-step communication in a micro-biog. The multi-steps of information communication are divided into first-step and non-first-step, and user influence is classified into five dimensions. Actual data from the Sina micro-blog is collected to construct the model by means of an approach based on structural equations that uses the Partial Least Squares (PLS) technique. Our experimental results indicate that the dimensions of the number of fans and their authority significantly impact the information of first-step conxrnunication. Leader rank has a positive impact on both first-step and non-first-step communication. Moreover, global centrality and weight of friends are positively related to the information non-first-step communication, but authority is found to have much less relation to it. 展开更多
关键词 user influence information multi-step communication micro-blog structural equations
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Evaluation on the Influence of Different Meteorological Government Micro-blog
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作者 Liu Xi Yin Zhaoyin +1 位作者 Liu Yingjie Liu Yan 《Meteorological and Environmental Research》 CAS 2014年第10期33-37,共5页
Taking Meteorological Knowledge official micro-blog " Meteorological Knowledge" and Beijing Meteorological Bureau official micro-blog " Meteorology Beijing" as the research objects,the differences of different typ... Taking Meteorological Knowledge official micro-blog " Meteorological Knowledge" and Beijing Meteorological Bureau official micro-blog " Meteorology Beijing" as the research objects,the differences of different types of meteorological government micro-blog and the contribution of each factor were analyzed by comparing changes of the number of fans,micro-blog comments and forwarding and other key elements during March1 to May 31 in 2012. The results showed that the number of fans was one of important indexes to determine the influence of meteorological government micro-blog,and the high active fans played a more prominent role. During the period of study,the fans number of " Meteorology Beijing" was far more than " Meteorological Knowledge",the daily micro-blog released number and comment forwarding number were both more than " Meteorological knowledge",but the proportion of active fans of " Meteorological knowledge" was larger than " Meteorology Beijing". Timeliness was of greater contribution to advancing the meteorological government micro-blog influence. During the period of study,the proportions of comments and forwarding number of morning weather forecast were the largest,the evening weather forecast took the second place,and the noon was the smallest.But the influence of noon weather forecast micro-blog increased most highly approximately by 15% because of the higher timeliness. The content and form also made great contribution to the influence of meteorological government micro-blog. Comparison of different types of meteorological micro-blog showed that,the number of fans and the influence of meteorological government micro-blog which mainly published real-time meteorological information were larger than which mainly published meteorological popular science knowledge. 展开更多
关键词 Meteorological government micro-blog Fans number INFLUENCE China
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Dynamic Detection Method of Micro-blog Topic Based on Time Series
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作者 Deyang Zhang Yiliang Han Xiaolong Li 《国际计算机前沿大会会议论文集》 2018年第2期17-17,共1页
关键词 TIME SERIES TOPIC DETECTION DYNAMIC micro-blog topicSingle-pass
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The Study of SINA micro-blog Opinion Leaders Effect on Network Public Opinion Transmission
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作者 Ge Tao Xue Chuanye 《Journal of Zhouyi Research》 2014年第6期68-72,共5页
关键词 领袖 网络 传播 博客 新浪 结构方程模型 中毒事件 复旦大学
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5-羟色胺转运蛋白显像剂^(11)C-DASB的自动化合成及Micro PET/CT显像
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作者 张晓军 刘健 +2 位作者 李云钢 田嘉禾 张锦明 《同位素》 CAS 2015年第1期1-6,共6页
目的:自动化合成5-羟色胺转运蛋白显像剂11 C-DASB并进行大鼠Micro PET/CT显像;方法:通过改变甲基化试剂、溶解前体溶剂及反应条件,得到优化的标记条件作为碳-11多功能合成模块的输入参数,进行自动化合成11 C-DASB,大鼠静脉注射11 C-DAS... 目的:自动化合成5-羟色胺转运蛋白显像剂11 C-DASB并进行大鼠Micro PET/CT显像;方法:通过改变甲基化试剂、溶解前体溶剂及反应条件,得到优化的标记条件作为碳-11多功能合成模块的输入参数,进行自动化合成11 C-DASB,大鼠静脉注射11 C-DASB 45 min后进行显像;结果:采用11 C-CH3-Triflate作为甲基化试剂,通入新配制的含1mg去甲基DASB前体的500μL DMSO溶液内,80℃下加热2min,标准率为63.7%,大鼠显像表明,11 C-DASB特异性的浓聚于SERT富集区域;结论:经优化,11 C-DASB自动化合成可得到较高产率,大鼠显像表明,其特异性浓聚于SERT富集区域,有望作为5-羟色胺转运蛋白显像剂。 展开更多
关键词 ^11C-DASB 5-羟色胺转运蛋白 micro PET/CT
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基于改进K-均值的微博热点话题发现方法
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作者 陈阳键 温秋华 《太赫兹科学与电子信息学报》 2023年第3期378-383,391,共7页
微博文本数据高维度、同义、多义特征明显,传统基于向量空间模型(VSM)联合K-均值的热点话题发现方法存在准确率低,计算复杂,聚类中心难以确定等问题。提出一种相关向量机(RVM)优化VSM的微博文本向量化方法,首先利用RVM的自适应特征选择... 微博文本数据高维度、同义、多义特征明显,传统基于向量空间模型(VSM)联合K-均值的热点话题发现方法存在准确率低,计算复杂,聚类中心难以确定等问题。提出一种相关向量机(RVM)优化VSM的微博文本向量化方法,首先利用RVM的自适应特征选择能力对VSM特征向量进行降维,然后利用主成分分析(PCA)方法确定K-均值算法的初始聚类中心,进而采用K-均值算法得到聚类结果,最后根据微博转发、评论和高影响力用户数量定义热度指数,热度指数最大的话题即为当前热点话题。采用实际微博文本数据集开展实验,结果表明所提方法相对于2种传统方法的准确率分别提升7.3%和1.1%,实时性分别提升45%和53%。 展开更多
关键词 热点话题发现 向量空间模型 话题聚类 数据降维 微博
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^(18)F-氟赤硝基咪唑micro PET/CT评价裸鼠乳腺癌早期放疗疗效实验研究 被引量:3
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作者 苏晓雨 徐慧琴 +3 位作者 汪会 余文静 张丹 谯凤 《安徽医科大学学报》 CAS 北大核心 2019年第2期203-206,共4页
目的探讨^(18)F-氟赤硝基咪唑micro PET/CT评价裸鼠MDA-MB231乳腺癌早期放疗疗效的价值。方法建立16只裸鼠MDA-MB231乳腺癌模型,将其按照随机对照原则分为两组:对照组(A组)、放疗组(B组),每组8只。每组裸鼠行micro PET/CT显像,测定每只... 目的探讨^(18)F-氟赤硝基咪唑micro PET/CT评价裸鼠MDA-MB231乳腺癌早期放疗疗效的价值。方法建立16只裸鼠MDA-MB231乳腺癌模型,将其按照随机对照原则分为两组:对照组(A组)、放疗组(B组),每组8只。每组裸鼠行micro PET/CT显像,测定每只裸鼠肿瘤SUVmax值。完成显像后,常规HE染色观察每组肿瘤组织形态学特征,免疫组化方法测定每组肿瘤细胞乏氧诱导因子-1α(HIF-1α)的表达情况。结果放疗前,对照组与放疗组SUVmax值差异无统计学意义(t=0. 375,P> 0. 05)。放疗组放疗后48 h裸鼠肿瘤组织SUVmax值较放疗前(t=9. 958,P <0. 05)、放疗后24 h(t=16. 506,P <0. 05)明显降低,差异有统计学意义(F=58. 860,P <0. 05)。放疗后24 h SUVmax值也低于放疗前24 h(t=5. 405,P <0. 05),差异有统计学意义。HE染色结果显示放疗组肿瘤细胞坏死较对照组更加明显。免疫组化结果显示放疗组放疗后HIF-1α表达阳性率明显低于放疗前(t=14. 802,P <0. 05),差异具有统计学意义。相关性分析结果显示肿瘤SUVmax与HIF-1α的表达呈明显正相关性(r=0. 865,P <0. 05)。结论^(18)F-氟赤硝基咪唑micro PET/CT可以监测肿瘤内部的乏氧状态,并且可以评价裸鼠MDA-MB231乳腺癌的早期放疗疗效。 展开更多
关键词 18F-氟赤硝基咪唑 micro PET/CT 放疗疗效 乏氧诱导因子-
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Stock Market Prediction Using Heat of Related Keywords on Micro Blog 被引量:4
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作者 Shengchen Zhou Xunzhi Shi +2 位作者 Yunchen Sun Wenting Qu Yingzi Shi 《Journal of Software Engineering and Applications》 2013年第3期37-41,共5页
Whether the stock market investors’ emotion can influence the stock market itself is one of the hot topic in financial research. In this paper, a method based on the heat of related keywords on Micro Blog is proposed... Whether the stock market investors’ emotion can influence the stock market itself is one of the hot topic in financial research. In this paper, a method based on the heat of related keywords on Micro Blog is proposed, as Micro Blog is an ideal source for capturing public opinions towards certain topic. We choose Shanghai Composite index as the research object, through correlation analysis, Granger causality analysis, and support vector machine classification, the results have shown that the keywords heat on micro blog can make a short-time prediction of stock market, and the keyword which expresses negative emotion have more powerful prediction ability. 展开更多
关键词 micro blog STOCK MARKET Prediction EMOTION SVM
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Effect of Surface Roughness in Micro-nano Scale on Slotted Waveguide Arrays in Ku-band
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作者 Na LI Peng LI Liwei SONG 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第3期595-603,共9页
Modeling of the roughness in micro-nano scale and its influence have not been fully investigated, however the roughness will cause amplitude and phase errors of the radiating slot, and decrease the precision and effic... Modeling of the roughness in micro-nano scale and its influence have not been fully investigated, however the roughness will cause amplitude and phase errors of the radiating slot, and decrease the precision and efficiency of the SWA in Ku-band. Firstly, the roughness is simulated using the electromechanical coupled(EC) model. The relationship between roughness and the antenna's radiation properties is obtained. For verification, an antenna proto- type is manufactured and tested, and the simulation method is introduced. According to the prototype, a contrasting experiment dealing with the flatness of the radiating plane is conducted to test the simulation method. The advantage of the EC model is validated by comparisons of the EC model and two classical roughness models (sine wave and fractal function), which shows that the EC model gives a more accurate description model for roughness, the maxi- mum error is 13%. The existence of roughness strongly broadens the beamwidth and raises the side-lobe level of SWA, which is 1.2 times greater than the ideal antenna. In addition, effect of the EC model's evaluation indices is investigated, the most affected scale of the roughness is found, which is 1/10 of the working wavelength. The proposed research provides the instruction for antenna designing and manufacturing. 展开更多
关键词 Slotted waveguide arrays - Roughness model micro/nano-scale Amplitude and phase errors Radiationcharacteristics
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基于铀媒指数的省级档案馆微博信息服务优化研究
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作者 周丽霞 陈昭宇 《山西档案》 北大核心 2024年第9期23-30,共8页
基于铀媒指数对8个省级档案馆微博的运营数据进行分析,探索省级档案馆微博信息服务的发展现状,发现其在重视程度、更新速度、内容特色、互动意识方面存在问题,进而提出省级档案馆微博信息服务的优化提升路径,以期为档案馆信息服务提供... 基于铀媒指数对8个省级档案馆微博的运营数据进行分析,探索省级档案馆微博信息服务的发展现状,发现其在重视程度、更新速度、内容特色、互动意识方面存在问题,进而提出省级档案馆微博信息服务的优化提升路径,以期为档案馆信息服务提供全新视角,为后续档案馆微博平台的应用研究提供参考。 展开更多
关键词 铀媒指数 档案馆 信息服务 微博
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基于R-C模型的微博用户社区发现 被引量:25
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作者 周小平 梁循 张海燕 《软件学报》 EI CSCD 北大核心 2014年第12期2808-2823,共16页
在微博市场营销、个性化推荐等应用中,发现兴趣和网络结构双内聚的用户社区起着至关重要的作用.现阶段,绝大多数的用户社区发现算法往往将用户联系与用户内容相隔离,从而导致其社区发现结果不够合理,而少数综合用户联系和内容的用户社... 在微博市场营销、个性化推荐等应用中,发现兴趣和网络结构双内聚的用户社区起着至关重要的作用.现阶段,绝大多数的用户社区发现算法往往将用户联系与用户内容相隔离,从而导致其社区发现结果不够合理,而少数综合用户联系和内容的用户社区发现算法较为复杂;LCA算法是重叠社区发现算法中算法效率较高且社区质量较好的算法,然而,其在聚类时未考虑边的真实兴趣体现.针对这些问题,构建了以关注关系为网络节点、以关注关系之间是否有共同用户为关注关系潜在的边、以关注关系所关联用户的兴趣集的交集为关注关系的兴趣特征,构建微博网络R-C模型,并探讨了其进行微博用户社区发现的方法,分析了该方法的复杂度.最后,以新浪微博数据集为实验,对照节点CNM算法和LCA算法,从兴趣内聚和网络结构内聚两方面进行分析,发现该方法能够发现更好的微博用户社区. 展开更多
关键词 微博 社区发现 关注关系 重叠社区
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结合自注意力机制和Tree-LSTM的情感分析模型 被引量:22
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作者 石磊 张鑫倩 +1 位作者 陶永才 卫琳 《小型微型计算机系统》 CSCD 北大核心 2019年第7期1486-1490,共5页
情感分析随着人工智能的发展而逐渐受到重视,微博情感分析旨在研究用户对于社会热点事件的情感倾向,研究表明深度学习在情感分析上具有可行性.针对传统循环神经网络模型存在信息记忆丢失、忽略上下文非连续词之间的相关性和梯度弥散的问... 情感分析随着人工智能的发展而逐渐受到重视,微博情感分析旨在研究用户对于社会热点事件的情感倾向,研究表明深度学习在情感分析上具有可行性.针对传统循环神经网络模型存在信息记忆丢失、忽略上下文非连续词之间的相关性和梯度弥散的问题,为此本文结合自注意机制和Tree-LSTM模型,并且在Tree-LSTM模型的输出端引入了Maxout神经元,基于以上两种改进基础上构建了SAtt-TLSTM-M模型.实验使用COAE2014评测数据集进行情感分析,实验结果表明:本文提出的模型相比于传统的SVM、MNB和LSTM模型准确率分别提高了16.18%、15.34和12.05%,其中引入了Maxout神经元的RMNN模型相对于LSTM模型准确率提高了4.10%,引入自注意力机制之后的Self-Attention+Tree-LSTM模型相比于Tree-LSTM模型准确率提高了1.85%,并在召回率和F值两项指标上均优于其他对比模型.由此证明,本文提出的SAtt-TLSTM-M模型可用于提高情感分析的准确率,具有一定的研究价值. 展开更多
关键词 微博情感分析 自注意力机制 Tree-LSTM模型 Maxout神经元
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北京市中心城绿地使用空间分布研究-基于大数据的实证分析 被引量:51
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作者 李方正 董莎莎 +1 位作者 李雄 雷芸 《中国园林》 北大核心 2016年第9期122-128,共7页
大数据作为众源地理数据的典型代表,具有数据量大、现势性好、信息丰富等优势。大量文献和研究已证实新浪微博签到数据对于市民活动分析具有实际意义,能够为城市空间研究和市民活动分布分析提供有效的数据源,弥补了社会调查数据样本量... 大数据作为众源地理数据的典型代表,具有数据量大、现势性好、信息丰富等优势。大量文献和研究已证实新浪微博签到数据对于市民活动分析具有实际意义,能够为城市空间研究和市民活动分布分析提供有效的数据源,弥补了社会调查数据样本量小和时间跨度短的不足。以北京市中心城公园绿地为研究范围,利用2013年北京市新浪微博签到数据,进行绿地使用研究,分析北京市中心城公园绿地的使用现状,并从绿地使用角度为城市绿地系统规划的修编提供建议。研究结果揭示:公园绿地使用率首都功能核心区高于城市功能拓展区;公园绿地使用受公园类型影响较大,而不同绿地类型的绿地使用影响因素不同;不同时期北京市中心城绿地使用会发生空间、游憩类型和立地条件上的变化。 展开更多
关键词 风景园林 大数据 中心城 绿地使用 新浪微博签到
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从黄金大米事件剖析指桑骂槐式的公众情绪--基于新浪微博的内容分析 被引量:15
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作者 靳明 靳涛 赵昶 《浙江社会科学》 CSSCI 北大核心 2013年第6期91-98,159,共9页
我国正处在社会转型的特定时期,社会矛盾不断积累,食品安全事件频发,使得公众对政府等相关机构缺乏信任,加剧了社会不安全感和不满感。通过对转基因食品——黄金大米实验事件的研究发现,公众对转基因食品的态度发生了转变,由以前对科技... 我国正处在社会转型的特定时期,社会矛盾不断积累,食品安全事件频发,使得公众对政府等相关机构缺乏信任,加剧了社会不安全感和不满感。通过对转基因食品——黄金大米实验事件的研究发现,公众对转基因食品的态度发生了转变,由以前对科技、伦理等一般性的归因转为指桑骂槐式的情绪宣泄。本文通过对公众心态和情绪的分析,对政府如何疏导公众情绪,缓解社会冲突提出了建议。 展开更多
关键词 黄金大米 转基因 指桑骂槐 情绪宣泄 微博
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基于微博舆情监测的K-Means算法改进研究 被引量:17
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作者 朱晓峰 陈楚楚 尹婵娟 《情报理论与实践》 CSSCI 北大核心 2014年第1期136-140,共5页
在分析传统K-Means算法局限性的基础上,提出了一种基于文本平均相似度的K-Means算法,通过对每个文本的平均相似度计算和排序,以文本平均相似度值为标准来选择初始聚类中心点。实验证明,改进后的算法,更适合微博文本的特点,聚类精度和聚... 在分析传统K-Means算法局限性的基础上,提出了一种基于文本平均相似度的K-Means算法,通过对每个文本的平均相似度计算和排序,以文本平均相似度值为标准来选择初始聚类中心点。实验证明,改进后的算法,更适合微博文本的特点,聚类精度和聚类稳定性均明显改善,微博舆情监测的质量大幅度提高。 展开更多
关键词 微博 网络舆情 K—Means算法
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