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221.
基于情感倾向识别的汽车评论挖掘系统构建   总被引:2,自引:0,他引:2  
文本情感识别是一个具有广泛应用前景的研究领域,它在信息检索、文本过滤、产品在线跟踪评价、民情民意调查分析、智能教学系统中都有着广泛应用。而汽车情感识别正在成为人们日益关注的研究热点。本文利用文本分类技术,采用分步骤分模型的设计方法,构建出汽车情感倾向识别系统,通过对汽车评论进行挖掘和分析,识别其情感倾向和演化规律,并以可视化的界面将结果展现给用户,从而向汽车生产商提供反馈信息,同时可以为汽车消费者提供购车指导。另外本文还就汽车语料库的建立,分类模型的构建以及本系统构建过程中的一些关键问题进行了分析和探讨。  相似文献   
222.
数字资源分类方法的探讨   总被引:1,自引:0,他引:1  
简要介绍了数字资源分类的常见分类方法及其意义,论述和评价了国内外几种数字资源分类方案,并提出自己的见解和建议.  相似文献   
223.
档案密级鉴定是档案管理和保密管理的重要内容,是对涉密档案动态管理的基础。由于缺乏理论研究和实践探索,档案密级鉴定一直游离于档案鉴定工作,导致已失去保密价值的档案仍按国家秘密要求管理,影响了档案信息资源的开发利用和作用发挥。文章阐述了档案密级鉴定的依据和意义,提出了从来源、内容、时间、环境等方面进行鉴定的方法。  相似文献   
224.
《中图法》第5版音乐类目 (J6) 刍议   总被引:1,自引:0,他引:1  
《中图法》第5版音乐类目的修订基于增设类目、修订类名、增补修改注释、删除/停用类目等多个方面,但在音乐理论类目的细化、音乐作品类目内容与形式的统一等颇受音乐专业图书馆关注问题的修订方面,仍然存在不足或缺失.建议修订工作借鉴《中图法》第3版音乐类目表成功修订的经验,使《中图法》音乐类目表真正成为一部能够全面、正确反映音乐艺术科学特点、具有长期稳定性的统一的音乐文献分类标准.  相似文献   
225.
基于支持向量机学习模型,使用万方期刊数据库中医学、卫生的有关标题和摘要数据,对医学、卫生大类下的R7中的9个小类进行了自动分类研究。在中文信息处理知识和技术的基础上选取分类特征,在分类过程中主要采取了基于低密度多特征的训练方法。在互信息、卡方统计、交叉熵和证据权值4个不同的统计特征量的开放测试中,自动分类的查全率和准确率都取得了相对令人满意的结果。  相似文献   
226.
While much prior research has focused upon how the Technology Transfer Offices (TTOs) and other contextual characteristics shape the level of university spinoffs (USO), there is little research on entrepreneurial potential among individual academics, and to the best of our knowledge, no comparative studies with other types of spinoffs exist to date. In this paper we focus on an important but neglected aspect of knowledge transfer from academic research involving the indirect flow to entrepreneurship by individuals with a university education background who become involved in new venture creation by means of corporate spinoffs (CSO) after gaining industrial experience, rather than leaving university employment to found a new venture as an academic spinoff. We argue that the commercial knowledge gained by industry experience is potentially more valuable for entrepreneurial performance compared to the academic knowledge gained by additional research experience at a university. This leads us to posit that the average performance of CSOs will be higher than comparable USOs, but the gains from founder‘s prior experiences will be relatively higher among USOs whose founders lack the corporate context. We investigate these propositions in a comparative study tracking the complete population of USOs and CSOs among the Swedish knowledge-intensive sectors between 1994 and 2002.  相似文献   
227.
Although age is not supposed to be a criterion for the award of the Nobel Prize, it is commonly believed that it does play a role. Indeed, econometric evidence in this paper also suggests such a role. However, the paper finds that, if there is a preference for older Nobel candidates, this is introduced during the nomination process. The paper actually finds that the Nobel Committee does not favor older nominees and that, if anything, it seems to partially offset the age premium introduced by the nominators.  相似文献   
228.
This article develops a general framework to describe the changes in university IPR regulations in Europe and their effects on the patenting activities of universities and on knowledge transfer processes. Understanding the effects of changes in IPR regulations on academic patenting is a complex issue, and parallels with the US case can be misleading. First, despite the general trend towards institutional ownership, university IPR regulations in Europe remain extremely differentiated and there is no one-to-one mapping to the US system. Second, it is difficult to disentangle the quantitative and qualitative effects of changes in IPR ownership regulations on academic patenting activities from the effects of concurrent transformations in the institutional, cultural and organizational landscape surrounding academic knowledge transfer. The article proposes a review and typological classification of national university IPR ownership systems on the basis of their development since 2000, and uses it to analyze the aggregate dynamics of academic patent ownership in several European countries. The analysis of patterns of ownership of academic patents shows that there has been a general increase in university patenting since 1990, with a significant slowdown (and even reduction in some countries) after early 2000s accompanied by a switch in academic patents ownership in favor of university ownership though preserving the European specificity of high company ownership of academic invented patents.  相似文献   
229.
Although sources and determinants of academic entrepreneurship have begun to command the attention of policy-makers and researchers, there remain many unanswered questions about how individual and social factors shape the decisions of academics to engage in entrepreneurial activities. Using a large-scale panel of academics from a variety of UK universities from 2001 to 2009, this paper examines how an academics’ level of entrepreneurial capacity in terms of opportunity recognition capacity, and their prior entrepreneurial experience shape the likelihood of them being involved in starting up a new venture. In addition, we explore what role university Technology Transfer Offices (TTOs) play in stimulating venture creation. The results show that individual-level attributes and experience are the most important predictors of academic entrepreneurship. We also find that the social environment surrounding the academic also plays an influential role, but its role is much less pronounced than individual-level factors. Finally, we show that the activities of the TTO play only a marginal, indirect role, in driving academics to start new ventures. We explore the implications of this analysis for policy and organizational design for academic entrepreneurship.  相似文献   
230.
高校科研分类评价探析   总被引:1,自引:0,他引:1  
应按照事物同类可比原则,针对科学研究中基础研究、应用开发研究、技术转移和技术服务等不同类型和自然科学、工程技术与人文科学、社会科学不同学科门类在研究内容与性质、目的与任务等各方面的差异,赋予各类科研工作不同的评价内涵和要求,建立健全高校科研分类、分学科评价的制度保障体系和差异化的评价体系.并适度淡化科研评价激励约束功能,营造宽松的科研环境.  相似文献   
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