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1.
张文萍  黎春兰 《现代情报》2013,33(2):21-23,124
在分析现有文本表示法的基础之处,提出一种以段落、语句、词语为层次结构的文本表示方法——文本空间表示模型,并在此模型基础上探讨一种以文本段落为基本单位的相似文本计算算法,以实现相似文本检测目标。最后建立测试集并在测试集上执行检测实验,结果表明此方具有较好的相似文本发现效果。  相似文献   

2.
文本的向量空间模型是把文本量化为空间里的向量,文本相似度的计算即对向量相似性的计算。本文通过分析传统的基于向量空间模型(VSM)文本相似度计算算法存在的不足,提出一种改进的文本相似度计算算法。改进算法充分考虑到了文本间向量空间模型相似度比较忽略了文本长度的缺点,引入文本长度参数,并在基于互信息的特征词抽取时考虑词频的因素对文本相似度的影响,有效减少了相似度低的文本干扰。实验结果验证了改进算法的有效性和准确性。  相似文献   

3.
中心思想是贯穿全文的核心和灵魂,理解中心思想有利于深入理解课文.本文就此具体谈论了从抓住标题、中心句、重点段落和语句几个方面来把握文章的中心思想.  相似文献   

4.
[目的/意义]从学术共同体的评论性引用视角出发,以引文全文本为基础,结合词频统计、深度学习等方法,探析引文文本中表征突破性评价的文本特征并构建自动识别模型以实现从海量文献中识别潜在突破性文献。[方法/过程]以诺贝尔生理学或医学奖获得者的关键文献以及Science十大科学突破主题的代表文献(医学领域)作为金标准突破性文献集并获取引用语句,对引用语句进行词频统计并结合人工筛选获取表征突破性评价的常用词。对引用语句进行人工标注,利用BERT、BIOBERT模型进行训练形成自动识别模型,并选择癌症领域进行实证分析。[结果/结论]结果表明,学术共同体在评价具有重大突破价值的文献时具有明显的文本特征;相较BERT模型,生物医学语言表示模型BIOBERT对突破性评价引用语句的识别能力明显增强,F1值为0.84。基于引用语句的自动识别模型能够较为精准地识别具有重要学术价值的文献并能在一定程度上实现早期识别和早期评价。  相似文献   

5.
网络环境下信息组织策略   总被引:5,自引:0,他引:5  
1 从文献组织到信息组织据日本科技信息中心 (JICST)估计 ,现在世界上每年大约发表科技文献 4 5 0万篇 ,其中科技期刊论文约为2 0 0万篇 ,专利文献约为 10 0万篇 ,其他类型的科技文献约为 15 0万篇左右。世界科技文献的出版具有如下特点 :①出版种类、出版数量增长迅速 ,出版速度不断加快。②文献分布极其分散。③文献语种迅速扩大 ;各种文献之间彼此交叉、重复日益严重。④文献新陈代谢迅速加快。同时 ,在科学领域 ,学科越来越多 ,越分越细 ,导致文献需求不断深入与集中。这种庞大的文献资源与特定用户需求之间的矛盾日益尖锐 ,文献组织…  相似文献   

6.
针对科技项目查重的需要,利用分词的结果,将科技项目文档转换为文本向量空间模型,抽取特征词,并将特征词的位置和词的长度2个因素考虑进来,提出一种TF-IDF值的改进计算方法,并实例验证该方法有一定的改善效果。  相似文献   

7.
研究了一种基于密度聚类模式下的依文本、段落、语句逐层分析的文本摘要自动生成方法。该聚类方法对噪声无敏感性,该层次分析方法对于长篇幅文本有较强的适应能力。同时,对特征向量的选取分别提出了一种线性及非线性加权模型。  相似文献   

8.
围绕文本聚类中的文本表示和相似度计算两个基本的问题,对目前学界提出的文本表示方法和相似度计算方法进行了分类和较为全面的综述,将文本表示模型分为向量空间模型、语言模型、后缀树模型、本体等,相似度计算方法分为基于向量空间模型的相似度计算,基于短语的相似度计算方法和基于本体的相似度计算方法。  相似文献   

9.
针对向量空间模型中语义缺失问题,将语义词典(知网)应用到文本分类的过程中以提高文本分类的准确度。对于中文文本中的一词多义现象,提出改进的词汇语义相似度计算方法,通过词义排歧选取义项进行词语的相似度计算,将相似度大于阈值的词语进行聚类,对文本特征向量进行降维,给出基于语义的文本分类算法,并对该算法进行实验分析。结果表明,该算法可有效提高中文文本分类效果。  相似文献   

10.
提出一种基于向量空间模型的科技文献自动分类方法.首先构建分类代表文本,计算单文本与分类代表文本之间的相似度;然后利用训练集计算出分类归属度,以判断某一文本分类的可能性,实现科技文献的自动分类.以3个学科的文献为例,验证该方法的可用性.  相似文献   

11.
CAS should stick to the principle of rendering service to, and giving impetus for, the development of China's science enterprise by making S&T innovations, said CAS President LU Yongxiang. The CAS president made the remarks in a recent talk to communicate the gist of the winter session of the Party's Leading-member Group at CAS, which was held from 7 to 11 January in Beijing.  相似文献   

12.
This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors.  相似文献   

13.
With great care, Dr. ZHOU Zhonghe takes out a package wrapped by cotton tissue from a drawer and says: "This is the gem of our collections: the fossil of a bird that lived 125 million years ago!" Then, pointing at a tiny mound, he explains: "Look, this is the claw and that is the head. It was in the egg shell and ready to hatch ... The species fell into a family of waterside inhabitants."  相似文献   

14.
Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China's projected climate warming could decrease the pest's numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007.  相似文献   

15.
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction.  相似文献   

16.
Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies.  相似文献   

17.
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means.  相似文献   

18.
Long-standing conflict between domain name registrants and trademark holders prompted the Internet Corporation for Assigned Names and Numbers (ICANN) to create a global, mandatory arbitration procedure known as the Uniform Dispute Resolution Policy (UDRP). The UDRP has been used in 2166 cases involving 3938 domain names as of 1 November 2000. The policy gives the initiator of a complaint, generally a trademark holder, the right to choose which ICANN-accredited dispute resolution service provider (RSP) will handle the case. During the preparation of the UDRP,some feared that complainant selection would lead to "forum shopping" that might bias the results. This article performs a statistical assessment of the forum-shopping thesis and finds support for it. There are statistically significant differences in the various RSPs' propensity to take away names from defendants; there are also major differences in the number of cases brought to each RSP. RSPs who take away names have the larger share of cases. The study examines other variables that might explain differences in market share, such as price, the plaintiff's nationality, or the time taken to decide a case. It finds that nationality and time also are correlated with market share. The study concludes that shopping for a favorable outcome is an important factor in the UDRP.  相似文献   

19.
Prof. Raymond C.K. Chen, a neuropsychologist with the CAS Institute of Psychology, has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology.  相似文献   

20.
Prof. SUN Changpu from the CAS Institute of Theoretical Physics and coworkers from University of Basel in Switzerland have worked out a way --at least in theory --to split a beam of molecules according to their chirality. The technique involves passing the molecules through three different laser beams and is similar to the famous Stern-Gerlach effect, whereby a beam of atoms passing through a magnetic field is split in two according to the atoms' spin states (Phys. Rev. Lett. 99 130403).  相似文献   

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