期刊文献+
共找到21篇文章
< 1 2 >
每页显示 20 50 100
基于TF-IDF与word2vec的台词文本分类研究 被引量:4
1
作者 但宇豪 黄继风 +1 位作者 杨琳 高海 《上海师范大学学报(自然科学版)》 2020年第1期89-95,共7页
为提高文本分类的准确性,针对健康节目台词文本各类别之间样本数量及各样本之间词数不平衡的特点,提出了一种基于word2vec均值算法及改进的词频-逆文本频率(TFIDF)算法的分类方法.该方法通过引入信息熵及修正因子,缓解了数据不平衡对分... 为提高文本分类的准确性,针对健康节目台词文本各类别之间样本数量及各样本之间词数不平衡的特点,提出了一种基于word2vec均值算法及改进的词频-逆文本频率(TFIDF)算法的分类方法.该方法通过引入信息熵及修正因子,缓解了数据不平衡对分类准确率及召回率造成的不良影响.实验结果表明:所提出的分类方法在准确率及召回率上与word2vec均值模型相比,分别提高7.3%及10.5%. 展开更多
关键词 词频-逆文本频率(TF-IDF) word2vec 信息熵 文本分类 机器学习 加权
下载PDF
WORD NEWS IN BRIEF(February 16-28, 1993)
2
《国际展望》 北大核心 1993年第5期32-32,共1页
In his first speech on February 17 to a joint session of Congress, US President Bill Clinton outlined his wision of smaller deficits through higher income taxes on the wealthy, increased energy taxes and selected spen... In his first speech on February 17 to a joint session of Congress, US President Bill Clinton outlined his wision of smaller deficits through higher income taxes on the wealthy, increased energy taxes and selected spending cuts including a one-year freeze on federal pay. US Secretary of State Warren Christopher arrived in Cairo on February 18 to start his six nation Middle East tour which will also take him to Jordan, Syria, Saudi Arahia, Kuwait, Israel and Lebanon. 展开更多
关键词 CLINTON SPENDING session SECRETARY INCOME FEBRUARY 16-28 Israel word Warren Jordan
下载PDF
WORD NEWS IN BRIEF(April 16-30, 1992)
3
《国际展望》 北大核心 1992年第9期32-32,共1页
China announced on April 16 its decision to send military observers and engineers to join UN transitional authorities in Cambodia. The contingent left Beijing on the same day. On April 21, Peruvian President Alberto F... China announced on April 16 its decision to send military observers and engineers to join UN transitional authorities in Cambodia. The contingent left Beijing on the same day. On April 21, Peruvian President Alberto Fujimori announced a 12-month plan to return Peru to democracy. He said he never intended to create a dictatorship when he launched his militarybacked crackdown on April 5 aimed at fighting corruption, 展开更多
关键词 NEWS word NEWS IN BRIEF April 16-30
下载PDF
KEY WORDS INDEX, RICE SCIENCE, VOL. 16, NOS. 1-4, 2009
4
《Rice science》 SCIE 2009年第4期I0005-I0006,共2页
关键词 gene NOS KEY wordS INDEX RICE SCIENCE VOL.16 NOS.1-4 2009 VOL
下载PDF
KEY WORDS INDEX, RICE SCIENCE, VOL. 14, NOS. 1-4, 2007
5
《Rice science》 SCIE 2007年第4期I0005-I0006,共2页
关键词 VOL KEY wordS INDEX RICE SCIENCE VOL.14 NOS.1-4 2007 gene NOS
下载PDF
KEY WORDS INDEX, 《RICE SCIENCE》, VOL. 12, NO. 1-4, 2005
6
《Rice science》 SCIE 2005年第4期I0007-I0009,共3页
关键词 VOL KEY wordS INDEX RICE SCIENCE VOL.12 NO.1-4 2005 NO
下载PDF
KEY WORDS INDEX, RICE SCIENCE, VOL. 13, NO. 1-4, 2006
7
《Rice science》 SCIE 2006年第4期I0005-I0006,共2页
关键词 VOL KEY wordS INDEX RICE SCIENCE VOL.13 NO.1-4 2006 NO
下载PDF
Word2000 de小词典
8
作者 申洋 《少年电脑世界(低年级)》 2003年第1期36-36,共1页
也许大家还不知道吧?Word2000里面带了一部“英汉-汉英词典”,使用起来特方便。单击“工具”菜单,指向“语言”,再选择“词典”,就打开了“词典”对话框。里面的内容简单明了。在“查阅”栏中输入你要查找的英语单词,按回车键或点击一... 也许大家还不知道吧?Word2000里面带了一部“英汉-汉英词典”,使用起来特方便。单击“工具”菜单,指向“语言”,再选择“词典”,就打开了“词典”对话框。里面的内容简单明了。在“查阅”栏中输入你要查找的英语单词,按回车键或点击一下“翻译”按钮,相应的中文解释就显示在右边的“替换为所译内容”中了。 展开更多
关键词 word2000 英汉-汉英词典 翻译
下载PDF
科技期刊“关键词”编写格式规范建议 被引量:1
9
作者 谢文亮 冯婷 《肇庆学院学报》 2023年第2期124-128,共5页
科技期刊中“关键词”一词有两种不同表达:Key words和Keywords,虽然编写形式不统一,没有造成太多文本分析的歧义,但给期刊规范、文献检索和作者写作带来不便,必须对其进行统一规范根据已有的公开的文献.,分析了Keywords和Keywords在英... 科技期刊中“关键词”一词有两种不同表达:Key words和Keywords,虽然编写形式不统一,没有造成太多文本分析的歧义,但给期刊规范、文献检索和作者写作带来不便,必须对其进行统一规范根据已有的公开的文献.,分析了Keywords和Keywords在英文中的定义、功能以及应用,对Keywords和Keywords的发展历史进行溯源后发现,Key word逐渐被Keyword所替代,并且从1995年后出版的字典中,再也没有出现过Key word的词条,其替代原因是科技论文发表数量剧增、科技论文交流的需要以及网络信息检索的兴起,使得Keyword成为信息检索和科技论文“关键词”的代号结合计算机信息检索和科技期刊中关键词的作用,对比结合GB/T7713-1987中对“关键词”的定义,提出使用Keywords作为科技期刊“关键词”一词的原因. 展开更多
关键词 科技期刊 关键词 信息检索 Key words KEYwordS GB/T 7713-1987
下载PDF
电商评论文本情感分析在品牌认知中的研究
10
作者 黄余 黄欣彬 《电子技术与软件工程》 2020年第18期172-173,共2页
本文首先利用爬虫技术获取评论数据,经过对评论语料库进行预处理,再利用Word2vec词向量技术构建构造特征-情感概念对词库,同时建立情感评分模型,最后将其应用于品牌商品特定特征的用户情感分析,并提供了相应的营销建议。通过此方法对电... 本文首先利用爬虫技术获取评论数据,经过对评论语料库进行预处理,再利用Word2vec词向量技术构建构造特征-情感概念对词库,同时建立情感评分模型,最后将其应用于品牌商品特定特征的用户情感分析,并提供了相应的营销建议。通过此方法对电商评论数据进行分析,能够对用户口碑的快速分析与准确把控,及时做好积极的应对措施,加强品牌营销能力,具有较高的商业推广前景。 展开更多
关键词 word2vec 构造特征-情感概念对 情感分析
下载PDF
面向中高频SSVEP脑机接口的编解码算法研究 被引量:7
11
作者 许敏鹏 吴乔逸 +2 位作者 熊文田 肖晓琳 明东 《信号处理》 CSCD 北大核心 2022年第9期1881-1891,共11页
基于稳态视觉诱发电位(steady-state visual evoked potentials,SSVEPs)的脑-机接口系统(brain-computer interface,BCI)通常使用低频强闪烁刺激诱发强特征脑电信号。尽管相关数据处理技术日臻成熟,但是系统使用舒适度差,训练时间较长... 基于稳态视觉诱发电位(steady-state visual evoked potentials,SSVEPs)的脑-机接口系统(brain-computer interface,BCI)通常使用低频强闪烁刺激诱发强特征脑电信号。尽管相关数据处理技术日臻成熟,但是系统使用舒适度差,训练时间较长。提高刺激频率能够有效缓解受试者的视觉疲劳,提高系统友好度,然而现有中高频SSVEP系统又存在指令集数量少、信息传输率(information transfer rate,ITR)低等缺陷。针对以上问题,本文基于中高频SSVEP脑电特征,提出并使用了包含空码的Code Words编码范式与集成任务相关成分分析(ensemble task-related component analysis,eTRCA)解码算法,并研究了该套编解码方法的适用性与可扩展性。本研究选择中高频段的4个频率(20、24、30、40 Hz)分别构建脑控字符拼写系统,单个频率的闪烁刺激可独立构建多达6个控制指令,联合多个频率理论上可实现指令集数量的成倍扩增。共有10位健康受试者参与了离线脑电实验,利用18~60 Hz带通滤波对脑电数据进行预处理,使用eTRCA算法进行特征识别。18指令集系统的理论平均分类准确率为96.71±1.69%,理论平均ITR达86.94±6.07 bits/min。以上结果表明,本研究提出的编解码算法能够有效诱发并准确识别中高频SSVEP的时-频-相多维特征,在此基础上通过增加编码单元频率种类、提高有效编码率、改进解码算法等方式有希望进一步提升系统性能。 展开更多
关键词 -机接口 中高频稳态视觉诱发电位 Code words
下载PDF
基于语义空间的抽取式单文档摘要方法
12
作者 杨山 杨雅婷 +1 位作者 温正阳 米成刚 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2019年第2期237-242,共6页
目前的抽取式单文档摘要方法未考虑原文中句子和原文语义信息相关度,针对该问题,提出一种基于语义空间的抽取式单文档摘要方法.首先,利用Word2Vec训练词向量以获取语义空间,并基于该语义空间表示句子和原文;然后,基于余弦相似度计算句... 目前的抽取式单文档摘要方法未考虑原文中句子和原文语义信息相关度,针对该问题,提出一种基于语义空间的抽取式单文档摘要方法.首先,利用Word2Vec训练词向量以获取语义空间,并基于该语义空间表示句子和原文;然后,基于余弦相似度计算句子与原文相似度值,并使用TextRank和词频-逆文本频率指数(TF-IDF)模型计算原文中句子的权重;最后,将相似度值与权重相结合得到句子的最终权重值.实验结果表明,该模型摘要质量优于基于深度学习的基线系统. 展开更多
关键词 文本摘要 word2Vec TextRank 词频逆文本频率指数 句子-原文相似度 序列到序列
下载PDF
Variation of sea ice extent in different regions of the Arctic Ocean 被引量:4
13
作者 CHEN Ping ZHAO Jinping 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第8期9-19,共11页
Sea ice in the Arctic has been reducing rapidly in the past half century due to global warming. This study analyzes the variations of sea ice extent in the entire Arctic Ocean and its sub regions. The results indicate... Sea ice in the Arctic has been reducing rapidly in the past half century due to global warming. This study analyzes the variations of sea ice extent in the entire Arctic Ocean and its sub regions. The results indicate that sea ice extent reduction during 1979-2013 is most significant in summer, following by that in autumn, winter and spring. In years with rich sea ice, sea ice extent anomaly with seasonal cycle removed changes with a period of 4-6 years. The year of 2003-2006 is the ice-rich period with diverse regional difference in this century. In years with poor sea ice, sea ice margin retreats further north in the Arctic. Sea ice in the Fram Strait changes in an opposite way to that in the entire Arctic. Sea ice coverage index in melting-freezing period is an critical indicator for sea ice changes, which shows an coincident change in the Arctic and sub regions. Since 2002, Region C2 in north of the Pacific sector contributes most to sea ice changes in the central Aarctic, followed by C1 and C3. Sea ice changes in different regions show three relationships. The correlation coefficient between sea ice coverage index of the Chukchi Sea and that of the East Siberian Sea is high, suggesting good consistency of ice variation. In the Atlantic sector, sea ice changes are coincided with each other between the Kara Sea and the Barents Sea as a result of warm inflow into the Kara Sea from the Barents Sea. Sea ice changes in the central Arctic are affected by surrounding seas. 展开更多
关键词 Key words: Arctic sea ice extent period of 4-6 years sea ice margin sea ice coverage indices
下载PDF
用电脑绘制生物学图解的技巧 被引量:5
14
作者 聂登福 张桂花 《生物学教学》 北大核心 2007年第5期33-34,共2页
Microsoft Office的PowerPoint-绘图或Word-绘图的旋转、翻转、透明功能和自选图形多的特点跟附件-画图移位精细准确的特点可以相互弥补各自功能的不足。
关键词 电脑绘图 PowerPoint绘图 word绘图 附件-画图
下载PDF
基于词嵌入的短文本扩展分类方法 被引量:3
15
作者 卢俊宇 周翔翔 《指挥信息系统与技术》 2020年第4期70-73,共4页
短文本因其文本较短和文本特征稀疏,导致信息量少且抗噪能力弱,因此短文本分类问题面临着巨大挑战。提出了词嵌入、词相似度和词重要性共同作用的文本表示方法,在Word2vec上引入词语相似度,并通过相似度与词频-逆文本频率(TF-IDF)的乘... 短文本因其文本较短和文本特征稀疏,导致信息量少且抗噪能力弱,因此短文本分类问题面临着巨大挑战。提出了词嵌入、词相似度和词重要性共同作用的文本表示方法,在Word2vec上引入词语相似度,并通过相似度与词频-逆文本频率(TF-IDF)的乘积来表示扩展词语对短文本的影响因子,并构造短文本向量,从而实现短文本分类。试验结果表明,该方法的分类准确率优于传统的词袋法、直接采用Word2vec训练的词向量、词向量不加权直接扩展和仅考虑TF-IDF加权扩展等方法。 展开更多
关键词 word2vec 词频-逆文本频率 相似度 文本表示 特征扩展
下载PDF
Instructions to authors
16
《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第28期i0003-i0004,共2页
An informative, structured abstract of no more than 250 words should accompany each manuscript. Abstracts for original contributions should be structured into the following sections: AIM: Only the purpose should be ... An informative, structured abstract of no more than 250 words should accompany each manuscript. Abstracts for original contributions should be structured into the following sections: AIM: Only the purpose should be included. METHODS: The materials, techniques, instruments and equipments, and the experimental procedures should be included. RESULTS: The observatory and experimental results, including data, effects, outcome, etc. should be included. Authors should present P value where necessary, and the significant data should accompany. CONCLUSION: Accurate view and the value of the results should be included. The format of structured abstracts is at: http://www.wjgnet.com/wjg/help/11 .doc 展开更多
关键词 Please list 3-10 key words that could reflect content of the study.
下载PDF
Information for Authors
17
《Journal of Beijing Institute of Technology》 EI CAS 2011年第1期F0003-F0003,共1页
An abstract not more than results and conclusion, should stracting journals, so it should 150 words, adequate as an index and summary, and including the aim, methods, appear at the beginning of the paper. The abstract... An abstract not more than results and conclusion, should stracting journals, so it should 150 words, adequate as an index and summary, and including the aim, methods, appear at the beginning of the paper. The abstract may be used in toto by the ab be self contained. 展开更多
关键词 Key words should be 3-8 pieces of words or phrases that will assist readers and indexers in cross-indexing thisstudy.
下载PDF
Instructions for Authors
18
《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2015年第3期334-334,共1页
Should be self-contained and adequate as a summary of the arti- cle; namely, it should indicate aim and significance, newly ob- served facts, conclusions, and the essential parts of any new theory, treatment, apparatu... Should be self-contained and adequate as a summary of the arti- cle; namely, it should indicate aim and significance, newly ob- served facts, conclusions, and the essential parts of any new theory, treatment, apparatus, technique, etc. The abstract should not con- tain literature citations. Define the nonstandard symbols and abbre- viations used in the abstract. Avoid "built-up" equations that cannot be rendered in linear fashion within the running text. The abstract should be concise and informative with a length of about 150 words. 展开更多
关键词 Should include 4-8 pieces of words or phases that are helpful forcross-indexing the paper.
下载PDF
《工程项目管理平台》软件在管理上的应用
19
作者 刘成伟 《安装》 2013年第8期63-64,共2页
《工程项目管理平台》软件通过浏览器-服务器,共享数据库内工程资源,方便管理者对工程信息的EXCEL、WORD数据输出,完善了工程项目全方位、全过程、全系统的监控与统筹分析,避免了人为管理工程项目过程中忽略的细节和相互关联的各个环节... 《工程项目管理平台》软件通过浏览器-服务器,共享数据库内工程资源,方便管理者对工程信息的EXCEL、WORD数据输出,完善了工程项目全方位、全过程、全系统的监控与统筹分析,避免了人为管理工程项目过程中忽略的细节和相互关联的各个环节,也避免了各管理部室分别对工程项目进行不全面、不系统、分散管理的工程管理模式。提升工程项目的管理水平和工程信息的正确性、及时性,使得管理信息资源的共享,减少人力资源,提高管理效率。 展开更多
关键词 工程项目管理平台 浏览器-服务器 EXCEL word
下载PDF
Achievements, challenges and prospects for the development of broadly protective multivalent vaccines and therapeutic antibodies against hand, foot and mouth disease 被引量:3
20
作者 Ke Lyu Rong Chen 《Science Bulletin》 SCIE EI CAS CSCD 2015年第15期1305-1315,共11页
Hand, foot and mouth disease(HFMD) is a significant health concern in the Asia–Pacific regions for infants and young children in recent years. However, no vaccines or therapeutics are available at present. The causat... Hand, foot and mouth disease(HFMD) is a significant health concern in the Asia–Pacific regions for infants and young children in recent years. However, no vaccines or therapeutics are available at present. The causative agents for HFMD include human enterovirus 71(EV71), coxsackievirus A16(CVA16) and some other viruses. Recently, tremendous progress has been made in the development of monovalent and bivalent vaccines against HFMD. A few neutralizing monoclonal antibodies against EV71 or CVA16 have been identified and characterized. Here, we reviewed some achievements for the development of broadly protective vaccines and neutralizing antibodies against HFMD, and discussed challenges and prospects toward broadly protective multivalent vaccines and therapeutic antibodies against HFMD. 展开更多
关键词 HAND foot and mouth disease (HFMD) Human enterovirus 71 (EV71) Coxsackievirus A 16(CVAI6) - Vaccine Neutralizing antibodies
原文传递
上一页 1 2 下一页 到第
使用帮助 返回顶部