共查询到20条相似文献，搜索用时 31 毫秒
1.
【目的/意义】针对基于关键词的科技文献聚类研究进行了一些探讨,包括：使用具有不同特征的关键词来
实现文献聚类在效果上有何差异;如何按特征对关键词进行选择来提高文献聚类效果。【方法/过程】按照关键词词
频与语义类型特征设置对照组进行实证研究,观察其对文献聚类密度及文献语义表示效果的影响。【结果/结论】单
独使用具有超高频、次高频、研究主题或限定范围特征的关键词进行文献聚类能使聚类密度较为合适;超高频特征
通常在其他频次中都具有体现,次高频词能同时反映不同频次的关键词特征,但次高频词对中频词特征的表示不
够全面;将语义类型不同的关键词分开来实现文献聚类,其效果好于将关键词进行组配,语义类型不同的关键词间
存在互斥性。【创新/局限】本文发现了在以关键词间的共现关系为基础来进行文献聚类时单独选择次高频或某一
语义类别的关键词来实现文献聚类具有较好效果,但缺少对关键词间语义结构关系的进一步研究。 相似文献
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《Information processing & management》2023,60(4):103405
Various keyword network methods are used to map scientific fields, but few studies have considered the semantic roles of keywords in such networks. This study proposes a term function–aware keyword citation network to fill this research limitation. Specifically, we first used a term function identification method to identify research questions and methods from scientific articles. Then, we constructed a question-method term citation network to represent the correlation structure of keywords. Next, we explored the topology characteristics, question-method bipartite network, and knowledge community structure of the generated network to validate its superiority in science mapping analysis. A dataset of 299,567 conference proceedings collected from the Association for Computing Machinery (ACM) digital library is used to evaluate the effectiveness of our methods. The results show that the term function identification model based on Bidirectional Encoder Representations from Transformers (BERT) achieves a score of 0.90 F1. And the question-method term citation network outperforms existing keyword citation methods in revealing association patterns between scientific knowledge and improving the interpretability of the knowledge structure of the computing field. We believe that our work expands the methodology of keyword citation network and science mapping analysis and provides guidance for considering the term function in various scenarios. 相似文献
3.
鉴于传统方法对科研成果关键词研究存在较强主观影响和较少考虑时间因素等问题,提出基于时间序列聚类的科研成果关键词分析方法。该方法通过统计分析方法验证关键词出现顺序在一定程度上反映了关键词反映主题思想的重要性,将关键词的重要度转化为时间序列数据,分别从重要度的数值和趋势两个角度出发,使用动态时间弯曲方法度量关键词重要度时间序列数据之间的相似性,结合近邻传播方法对关键词时间序列数据之间的相似性矩阵进行聚类分析,实现科研成果的关键词分析研究。通过对某科研管理类重要期刊2008—2017年期间刊发的科研成果论文关键词研究发现：新方法不仅可以对科研成果中关键词的关注热度和趋势进行聚类划分,自适应地找到中心关键词作为相应类别的特征代表对象,还能为科研成果关键词的主题分析提供理论方法和决策支持。 相似文献
4.
【目的/意义】从海量自助餐用户评论数据中抽取有效关键词构建主题和主题词,协助商家了解用户口碑,
进而更好的改善餐饮行业的管理水平。【方法/过程】通过融合TF-IDF、TextRank和LMKE三种不同的关键词抽取
方法获取最优关键词,再对抽取的关键词进行语义聚类、主题识别、主题词挖掘和主题权重计算,最后在采集的美
团数据集上进行验证方法的有效性。【结果/结论】实验结果表明,三种关键词抽取方法的融合比单个关键词算法效
要好,文本评论聚类后的主题分别是：味道、菜品、环境、服务、价格,主题的重要程度依次是：味道 36.2%、服务
22.9%、价格15.1%、环境13.6%、菜品12.2%。实验结果证实,通过该方法能够有效识别和构建主题及主题词,并计算
出用户对于不同主题关注的重点内容,同时为餐饮行业主题及主题词挖掘和应用研究提供了一定的理论和技术基
础。【创新/局限】提出一种半监督语义聚类的主题识别、主题词构建和主题权重评估方法;不足之处在于本次实验
仅以武汉地区的美食自助餐评论为主,其构建的主题适用性范围有限。 相似文献
5.
基于改进局部空间自相关分析的萝北县耕地保护分区 总被引：5，自引：0，他引：5
本文通过结合耕地面积与距离修正反距离空间权重矩阵,首次构建改进的局部空间自相关分析方法,并运用空间计量模型的信息准则验证其合理性和可行性;以耕地质量指数为空间变量,运用改进的局部空间自相关分析法,分析黑龙江省萝北县不同类型耕地质量的空间聚集特征及空间关联结果,并据此提出详细的耕地保护分区方案。研究结果表明：①验证了改进的空间自相关分析方法的合理性和准确性;②不同类型耕地质量在空间分布上呈现相似的集聚性规律。正相关类型（HH型和LL型）多以带状或片区形式出现,聚集性较强;负相关类型（HL和LH型）无明显集中区域,面积较小,且零星分布;③将耕地保护划分为核心保护区、重点改良区、适度保护区和综合改良区4个一级类和11个二级类,并分别从耕地自然条件、利用水平和产出效益角度提出了相应的耕地保护措施。 相似文献
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[目的/意义] 从关键词语义类型和学术文献老化两个维度出发挖掘学术论文价值,为学者推荐符合其研究需求并在时间维度上具有较大参考意义的学术论文。[方法/过程] 首先,将学术论文关键词按语义类型进行划分|随后,基于共现关系计算同类型关键词间相似度,基于关键词相似度得到论文在语义类型上的相似度|然后,借用文献老化思想,计算不同类型论文的时间价值|最后,结合论文在语义类型上的相似度及时间价值,生成论文推荐列表从而进行推荐工作。[结果/结论] 实证结果表明,使用该方法推荐的论文,一方面与学者研究方向相符|另一方面在时间维度上也具有较大价值,推荐的论文质量较高。 相似文献
7.
《The Journal of High Technology Management Research》2004,15(1):37-50
Patent documents are an ample source of technical and commercial knowledge and, thus, patent analysis has long been considered a useful vehicle for R&D management and technoeconomic analysis. In terms of techniques for patent analysis, citation analysis has been the most frequently adopted tool. In this research, we note that citation analysis is subject to some crucial drawbacks and propose a network-based analysis, an alternative method for citation analysis. By using an illustrative data set, the overall process of developing patent network is described. Furthermore, such new indexes as technology centrality index, technology cycle index, and technology keyword clusters are suggested for in-depth quantitative analysis. Although network analysis shares some commonality with conventional citation analysis, its relative advantage is substantial. It shows the overall relationship among patents as a visual network. In addition, the proposed method provides richer information and thus enables deeper analysis since it takes more diverse keywords into account and produces more meaningful indexes. These visuals and indexes can be used in analyzing up-to-date trends of high technologies and identifying promising avenues for new product development. 相似文献
8.
《Information processing & management》1999,35(3):401-420
This paper describes the development and application of visualisation techniques for users to access and explore information in a digital library effectively and intuitively. Salient semantic structures and citation patterns are extracted from several collections of documents, including the ACM SIGCHI Conference Proceedings (1995–1997) and ACM Hypertext Conference Proceedings (1987–1998), using Latent Semantic Indexing and Pathfinder Network Scaling. The unique spatial metaphor leads to a natural combination of search and navigation within the same semantic space in a 3-dimensional virtual world. Author co-citation patterns are visualised through a number of author co-citation maps in attempts to reveal the structure of the hypertext, including an overall co-citation map of 367 authors and three periodical maps. These maps highlight predominant research areas in the field. This approach provides a means for transcending the boundaries of collections of documents and visualising more profound patterns in terms of semantic structures and co-citation networks. 相似文献
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In the last 20 years, microfinance has moved from a promise to reality, although with ups and downs. This paper reviews 1874 papers published from 1997 to 2017 to perform a scientometric analysis of the microfinance field. The literature review is based on bibliometric data: keyword co-occurrence networks and citation networks were exploited for knowledge mapping. Data analysis shows the two research traditions: papers focusing on clients (welfarists) and papers focusing on microfinance entities themselves (institutionalists). Institutionalism, which had little presence in the early research in microfinance, now exhibits great strength. A chronological analysis reveals the evolution of the topics most interesting to researchers: the first stage described the innovations of the microcredit practices and their impact; the second and very expansive stage in which microfinance institutions’ peculiarities were analyzed; and nowadays the sector is mature but with negative aspects arising, such as mission drift. The keywords analysis discovers emerging research topics, shows the use of sophisticated techniques, and recognizes an emerging trend of the sector: achieving financial inclusion. 相似文献
11.
《Information processing & management》2023,60(5):103468
Assessing the similarity of scientific outputs based on an indicator has not been addressed much so far. The topic, however, may find several potential applications which can help enrich procedures of ranking, research monitoring, and scientific policy-making. The present study offers a new method to quantify such similarities based on keyword co-occurrence matrices. In the proposed method, first, the keyword co-occurrence networks are transformed into their associated newly defined fuzzy sets, named as scientosemantic domains. Then, a fuzzy distance between the two domains is found based on an arbitrary indicator. In this paper, the three indicators of frequency, development and investment appeal are used. The proposed method is implemented for five types of concept comparison. For each type, concepts are represented by a canonical keyword with different field codes. Scientosemantic domains of concepts are sourced out of bibliometric data obtained from appropriate queries on SCOPUS. Number of keywords used to define scientosemantic domains ranges from about 30 to 800. Since indicator-based comparison of scientosemantic domains are not dealt with in the literature, the obtained distances between concepts are verified by qualitative and expert evaluations. For all cases, frequency- and development-based distances are less than those for investment appeal; while crisp distances for the latter extend beyond 0.6, the former does not exceed 0.3. The greatest distances are observed for investment appeal in technology-related keywords. 相似文献
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This paper presents a novel IR-style keyword search model for semantic web data retrieval, distinguished from current retrieval methods. In this model, an answer to a keyword query is a connected subgraph that contains all the query keywords. In addition, the answer is minimal because any proper subgraph can not be an answer to the query. We provide an approximation algorithm to retrieve these answers efficiently. A special ranking strategy is also proposed so that answers can be appropriately ordered. The experimental results over real datasets show that our model outperforms existing possible solutions with respect to effectiveness and efficiency. 相似文献
14.
重大科技基础设施（简称重大设施）是具有前沿性、创新性、规模性及影响力的科学研究系统,在国家科技创新体系中占据重要地位。为了深刻认识重大设施的战略价值、充分发挥设施科研潜力、支撑未来设施的统筹布局,需要深入研究其对学科领域发展的影响作用。以专用型重大设施中的对撞机为研究对象,分析其论文成果的引文分布及主题强度演化,研究了重大设施对学科领域发展的影响过程,定义了不同影响类型,并形成了判别不同类型的三维战略坐标。在对比中、日、欧三方对撞机的成果产出和影响情况后,提出了相关政策建议。 相似文献
15.
基于科技金融与生态概念相融合的区域科技金融发展的崭新视角,首先依据生态原理构建科技金融生态系统;其次建立评价体系,基于熵权TOPSIS法对科技金融生态系统发展展开评价分析;最后采用空间自相关分析法,分析2009—2016年我国科技金融生态系统空间演化趋势。研究发现:我国科技金融发展水平较高的省份基本聚集在东部地区,东部与其他地区科技金融发展的差异最显著且该差异逐年递增;总体呈现正向空间自相关性且处于萧条区的省份多;未来可能会形成东部地区辐射扩散、中部地区稳步增长、西部地区差异化发展的空间格局。 相似文献
16.
基于数据包络分析的我国农业生产效率区域差异分析 总被引：3，自引：0，他引：3
基于数据包络分析方法探讨全国农业生产效率及其变动情况,并利用空间自相关方法对变动情况的空间集聚特征进行分析,结果表明:(1)台湾各年份农业技术的综合效率、纯技术效率及规模效率均达到最优状态,远高于大陆各省份的均值。(2)全国各省份农业全要素生产率指数都大于1,呈增长态势且东部地区的增长速度高于西部地区,西部地区高于中部地区。(3)根据各省份农业全要素生产率及其分解值的变化特点,全国省份可划分为四类问题省份。(4)全国各省份农业全要素生产率增长差异的空间集聚特征明显,且集聚趋势逐渐增强。 相似文献
17.
中国省域碳强度集群的空间统计分析 总被引：1，自引：0，他引：1
论文使用空间统计分析中的全局Moran’s I、局域Moran’s I等指数对2001-2012年间我国碳强度的空间自相关性以及集群情况进行分析,发现全国省域碳强度的空间自相关性为正,东部地区内部省域的碳强度空间自相关现象非常明显,西部地区相对不明显,中部最弱。西部地区省份的碳强度多为高-高聚集,以甘肃、陕西、内蒙古3个地区为代表,东部地区多为低-低聚集,以浙江、福建、广东、江西4个地区为代表。论文还进一步结合资源禀赋、能源供需分布、产业结构和收入水平等对上述地区碳强度聚集的原因进行了分析,提出针对性的政策建议。 相似文献
18.
利用CiteSpace软件分析该领域的研究现状与热点,对Web of Science数据库中2010-2019年突发公共卫生事件领域共5412篇相关文献进行核心国家分析、期刊共被引分析、文献共被引分析、关键词共现分析和关键词突发性检测.研究发现,突发公共卫生事件研究热点领域为传染病学、急诊医学、应急管理和空气污染,其中有关引发重大传染病疫情的病毒研究一直是研究的热点. 相似文献
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《Information processing & management》2023,60(1):103142
In sponsored search advertising (SSA), keywords serve as the basic unit of business model, linking three stakeholders: consumers, advertisers and search engines. This paper presents an overarching framework for keyword decisions that highlights the touchpoints in search advertising management, including four levels of keyword decisions, i.e., domain-specific keyword pool generation, keyword targeting, keyword assignment and grouping, and keyword adjustment. Using this framework, we review the state-of-the-art research literature on keyword decisions with respect to techniques, input features and evaluation metrics. Finally, we discuss evolving issues and identify potential gaps that exist in the literature and outline novel research perspectives for future exploration. 相似文献
20.
粤港澳大湾区已经成为我国创新驱动发展的桥头堡,助力我国加快提高科技创新能力。本文选取粤港澳大湾区“9+2”城市历年科技创新能力相关数据构建成面板数据集。为了能够进一步分析湾区区域间的科技创新能力差异,将湾区划分成西湾、中湾、东湾和港澳湾。基于空间差异、空间自相关以及空间计量的分析理论与方法,借助GeoDa、ArcGIS和Stata数据分析软件,深层次地探究粤港澳大湾区科技创新能力的空间结构演变及其影响因素。 相似文献