第16届世界男子篮球锦标赛挡拆配合新特点研究   总被引：1，自引：0，他引：1  

霍子文  张戈 《中国体育科技》2012,48(3):45-51

以第16届世界男子篮球锦标赛8强球队和中国队的挡拆配合临场表现为研究对象,按照"挡的动作效果、挡后处理球方式"分别建构观测指标体系,采取视频分析、专家访谈和数理统计等方法研究当前世界男子篮球挡拆配合新特点以及中国队存在的差距。初步分析表明,美国队挡拆总频次最低;世界强队"常规挡"和"接顺挡"两项指标比较均衡,中国队"接顺挡"欠缺;只有塞尔维亚队较好地掌握了"双人连贯挡";中国队"传弱"与各队差距较大;塞尔维亚队挡拆的系统性最好,土耳其队、中国队挡拆的系统性最差。系统聚类结果是:俄罗斯队、斯洛文尼亚队、立陶宛队,西班牙队、阿根廷队、土耳其队,中国队,塞尔维亚队,美国队分别聚为一类。通过检验聚类有效性表明聚类结构良好。通过计算聚类中心及其各指标权重(%)并结合视频观察和专业判断进一步分析各聚类特征:俄罗斯队、斯洛文尼亚队、立陶宛队挡拆具有创新性且配合默契,西班牙队、阿根廷队、土耳其队挡拆时组织后卫控球能力强且配合具有突然性和威胁性,塞尔维亚队挡拆质量高、系统性强且有绝招,中国队挡拆比较被动,美国队挡拆表现最差。最后总结了当前世界男篮挡拆配合的8个新特点。  相似文献   

LTE系统中一种利用DRX降低UE功耗的视频流调度方法     

田建军  邱玲 《中国科学院研究生院学报》2012,29(4):518-523

提出一种利用DRX(discontinuous reception)降低UE(user equipment)功耗的视频流调度方法,该方法在保证数据包时延要求的同时,减少了InactivityTimer的开启次数,增加了UE的休眠时间.仿真结果表明,相比已有的DRX机制下的实时业务调度方法,该方法可以在丢包率相同的情况下,显著降低UE的功耗.  相似文献   

Quantifying the impact of concept recognition on biomedical information retrieval     

Sarvnaz Karimi  Justin Zobel 《Information processing & management》2012,48(1):94-106

In ad hoc querying of document collections, current approaches to ranking primarily rely on identifying the documents that contain the query terms. Methods such as query expansion, based on thesaural information or automatic feedback, are used to add further terms, and can yield significant though usually small gains in effectiveness. Another approach to adding terms, which we investigate in this paper, is to use natural language technology to annotate - and thus disambiguate - key terms by the concept they represent. Using biomedical research documents, we quantify the potential benefits of tagging users’ targeted concepts in queries and documents in domain-specific information retrieval. Our experiments, based on the TREC Genomics track data, both on passage and full-text retrieval, found no evidence that automatic concept recognition in general is of significant value for this task. Moreover, the issues raised by these results suggest that it is difficult for such disambiguation to be effective.  相似文献   

User relevance criteria choices and the information search process     

Arthur Taylor Author Vitae 《Information processing & management》2012,48(1):136-153

Relevance judgments occur within an information search process, where time, context and situation can impact the judgments. The determination of relevance is dependent on a number of factors and variables which include the criteria used to determine relevance. The relevance judgment process and the criteria used to make those judgments are manifestations of the cognitive changes which occur during the information search process.Understanding why these relevance criteria choices are made, and how they vary over the information search process can provide important information about the dynamic relevance judgment process. This information can be used to guide the development of more adaptive information retrieval systems which respond to the cognitive changes of users during the information search process.The research data analyzed here was collected in two separate studies which examined a subject’s relevance judgment over an information search process. Statistical analysis was used to examine these results and determine if there were relationships between criteria selections, relevance judgments, and the subject’s progression through the information search process. Findings confirm and extend findings of previous studies, providing strong statistical evidence of an association between the information search process and the choices of relevance criteria by users, and identifying specific changes in the user preferences for specific criteria over the course of the information search process.  相似文献   

An agenda for green information retrieval research     

Gobinda Chowdhury 《Information processing & management》2012

Nowadays we use information retrieval systems and services as part of our many day-to-day activities ranging from a web and database search to searching for various digital libraries, audio and video collections/services, and so on. However, IR systems and services make extensive use of ICT (information and communication technologies) and increasing use of ICT can significantly increase greenhouse gas (GHG, a term used to denote emission of harmful gases in the atmosphere) emissions. Sustainable development, and more importantly environmental sustainability, has become a major area of concern of various national and international bodies and as a result various initiatives and measures are being proposed for reducing the environmental impact of industries, businesses, governments and institutions. Research also shows that appropriate use of ICT can reduce the overall GHG emissions of a business, product or service. Green IT and cloud computing can play a key role in reducing the environmental impact of ICT. This paper proposes the concept of Green IR systems and services that can play a key role in reducing the overall environmental impact of various ICT-based services in education and research, business, government, etc., that are increasingly being reliant on access and use of digital information. However, to date there has not been any systematic research towards building Green IR systems and services. This paper points out the major challenges in building Green IR systems and services, and two different methods are proposed for estimating the energy consumption, and the corresponding GHG emissions, of an IR system or service. This paper also proposes the four key enablers of a Green IR viz. Standardize, Share, Reuse and Green behavior. Further research required to achieve these for building Green IR systems and services are also mentioned.  相似文献   

How doctors search: A study of query behaviour and the impact on search results     

Marianne Lykke  Susan Price  Lois Delcambre 《Information processing & management》2012

Professional, workplace searching is different from general searching, because it is typically limited to specific facets and targeted to a single answer. We have developed the semantic component (SC) model, which is a search feature that allows searchers to structure and specify the search to context-specific aspects of the main topic of the documents. We have tested the model in an interactive searching study with family doctors with the purpose to explore doctors’ querying behaviour, how they applied the means for specifying a search, and how these features contributed to the search outcome. In general, the doctors were capable of exploiting system features and search tactics during the searching. Most searchers produced well-structured queries that contained appropriate search facets. When searches failed it was not due to query structure or query length. Failures were mostly caused by the well-known vocabulary problem. The problem was exacerbated by using certain filters as Boolean filters. The best working queries were structured into 2–3 main facets out of 3–5 possible search facets, and expressed with terms reflecting the focal view of the search task. The findings at the same time support and extend previous results about query structure and exhaustivity showing the importance of selecting central search facets and express them from the perspective of search task. The SC model was applied in the highest performing queries except one. The findings suggest that the model might be a helpful feature to structure queries into central, appropriate facets, and in returning highly relevant documents.  相似文献   

Summarisation of the logical structure of XML documents     

Zoltán Szlávik  Anastasios Tombros  Mounia Lalmas 《Information processing & management》2012

Summarisation is traditionally used to produce summaries of the textual contents of documents. In this paper, it is argued that summarisation methods can also be applied to the logical structure of XML documents. Structure summarisation selects the most important elements of the logical structure and ensures that the user’s attention is focused towards sections, subsections, etc. that are believed to be of particular interest. Structure summaries are shown to users as hierarchical tables of contents. This paper discusses methods for structure summarisation that use various features of XML elements in order to select document portions that a user’s attention should be focused to. An evaluation methodology for structure summarisation is also introduced and summarisation results using various summariser versions are presented and compared to one another. We show that data sets used in information retrieval evaluation can be used effectively in order to produce high quality (query independent) structure summaries. We also discuss the choice and effectiveness of particular summariser features with respect to several evaluation measures.  相似文献   

基于文本质量的文献检索结果的系统聚类     

王筠  孙晓雅  刘军 《情报理论与实践》2012,35(10):115-117

采用系统聚类的方法对文献数据库的检索结果按其质量进行聚类,并通过实例说明这种方法的可行性和有效性。检索结果经过聚类方法处理后,用户可迅速了解检索结果的质量等级分布,从而对不同等级的检索结果采用不同的阅读方式。这样便能节省用户的阅读时间,提高检索效率。该项研究对今后开发针对检索结果的文本聚类插件奠定了基础。  相似文献   

基于中底层视觉信息的体育视频智能分析     

屈萍  屈胜国  康涛  赵云雷 《体育成人教育学刊》2012,28(3):49-51

在借鉴了计算机视觉技术和多媒体处理算法的基础上,提出了一种基于全自动高效视频分析框架的分析和总结的体育视频分析结构。本视频分析框架拟从底层特征提取、中级关键基元生成出发,初步实现体育视频中的镜头分类和运动对象识别以及跟踪等。分析框架中包含了一些中低级别的足球视频镜头分类处理算法,如主色区域检测,鲁棒镜头边界检测,以及目标检测等等。  相似文献   

微信小程序在专利信息检索与跟踪中的应用     

张显生  余必军  王伟宁  章捷  周玉兵 《中国发明与专利》2022,(2):60-69

微信小程序是移动互联网时代专利信息检索与跟踪的新工具.通过专利信息检索相关微信小程序的检索统计与对比分析,比较了不同小程序的特点.以核燃料技术领域为例,具体介绍了小程序在专利信息检索、专利信息跟踪等方面的应用.案例表明,利用好微信小程序,有助于提高专利信息的检索与利用水平.  相似文献