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1.
潘正高 《情报科学》2012,(5):708-712,786
介绍命名实体识别在文本信息处理领域的重要地位,分析了中文命名实体识别存在的困难,介绍中文命名实体识别的一般过程、评价标准及方法。提出了一种在构造内部规则和外部规则的同时采用概率统计的中文命名实体的识别方法,并利用这种基于规则和统计相结合的方法。实验证明该方法获得了较高的准确率和召回率,具有可行性和合理性,同时也指出了它的局限性。  相似文献   

2.
命名实体识别(Named Entity Recognition)是指识别文本中具有特定意义的实体,主要包括人名、地名、机构名、专有名词等.首先对我国关于命名实体识别研究的文献进行了总结,给出命名实体识别的主要方法及模型.并针对文献中对这些命名实体识别方法的效果进行统计分析,探讨各种识别对象、识别模型的效果及适用性.经过对现有研究文献的统计,结论为:在不考虑运行效率的情况下,对于机构名,识别效果最好的是层叠CRF模型;对于地名,测试效果最好的是CRF方法与专家知识相结合;人名识别方法中表现不错的则是边界模版和局部统计相结合的模型.  相似文献   

3.
潘国巍  吉久明  李楠  郑荣廷 《现代情报》2011,31(11):163-165
与基于词典和基于规则的识别方法相比,统计机器学习方法更加适合被应用到命名实体的识别工作中来。本文主要在中文化学物质名称的识别工作中,考察两类统计机器学习模型识别效果及识别效率的优劣,实验结果表明,在所取训练语料与测试语料相同的情况下,以CRF模型为代表的条件概率模型可以展现出更好的实验性能。  相似文献   

4.
在分析工程文本中命名实体实际特征的基础上,提出一种基于CRF与规则相结合的工程领域命名实体识别方法。在完善用户词典并对文本进行分词后,以短语级的粒度为原则从中确定特征,将文本交由CRF算法进行处理;分析CRF的处理结果,根据语言学规律及工程文本特点编写规则,对CRF处理结果进行优化。实验表明,该方法的全局F1值能够达到93.45。  相似文献   

5.
我国制造业产业集群识别研究   总被引:3,自引:2,他引:1  
在介绍和评价几种主要的国外的产业集群识别方法基础上,选取“地点系数”法(雇员集中度系数法)对我国制造业进行了产业集群识别的实证分析,得出了我国现有的制造业产业集群集聚度高和集聚度低的区域以及制造业产业集群程度增长快的地区,并且对识别结果进行了实证检验和分析。  相似文献   

6.
分析描述基于关联数据进行科研机构评价的相关研究现状和未来发展方向。利用Google Scholar、Springer、CNKI等检索研究主题相关的文献进行调研分析,根据评价方法的不同进行归类分析。基于关联数据进行科研机构评价仍处于探索阶段,相关研究不是很多。利用关联数据进行科研机构评价还存在整体机构关联数据量不是很丰富、部分数据质量低下等问题,获取更多机构语义关系、数据和提高评价方法的评价准确性将是未来研究的重点。  相似文献   

7.
广东省属科研机构分类改革已经进行了十年,取得了明显的成效,但也暴露出了不少的问题和矛盾,需要通过进一步深化改革来解决。推进广东省属科研机构的进一步深化改革,需要对各类机构的改革成效进行科学的评价。通过调研和分析,提出了广东省属科研机构深化改革的评价内容,并以此为基础,应用德尔菲法与层次分析法,提出了广东省属科研机构深化改革的评价指标体系,根据调研数据进行定量评价。  相似文献   

8.
公益型科研机构的体制改革是我国今后科技体制改革的重点之一。文章在分析我国公益型科研机制现状及中外同类机构对比分析的基础上,就如何推进我国公益型科研机构体制改革问题进行初步探讨并提出相关的建议。  相似文献   

9.
研究提高翻译算法的翻译准确性问题。由于英语名词短语语法复杂、规则多,导致传统机器翻译算法存在效率低、准确率不高难题。为提高英语名词短语识别准确率,提出一种粗糙集的名词短语识别方法。粗糙集方法把英语名词短语识别当成一个决策问题,通过粗糙集理论对特征约简和规则优化,最后对其进行进识别。采用粗糙集方法对WSJ英语名词短语样本进行仿真实验,仿真结果表明,粗糙集的名词短语识别正确率高于其它翻译方法,是一种有效英语名词短语机器识别方法。为实际设计提供依据。  相似文献   

10.
依据我国技术开发类科研机构的基本特征,从创新支撑、活动、产出、影响、运营能力五大维度出发,提出技术开发类科研机构创新能力评价指标体系。利用熵权法求取各指标权重大小,通过直觉模糊数相关系数计算各科研机构与理想、临界机构加权相关系数,提出直觉模糊排序方法。最后,选取广东省属10所技术开发类科研机构为样本,并利用该方法进行创新能力评价研究,给出提升该类科研机构创新能力的相关建议。  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

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.
<正>In Xishuangbanna,one of China’s most biodiverse regions,landscape has changed dramatically during the past three decades due to the conversion of tropical rainforest to rubber plantations.In steep areas,terraces are often constructed before planting rubber trees,which causes two important changes in the soil:the destabilization of soil in the bench terraces and the increased vulnerability of unvegetated riser faces to erosion.Few studies have documented the nature and intensity of erosion on bench terraces.Prof.LIU Wenjie and his colleagues from the Xishuangbanna Tropical Botanical Garden(XTBG)conducted a study in Menglun County(21°5′39″N,101°15′55″E),Xishuangbanna to evaluate the influence  相似文献   

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