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排序方式: 共有563条查询结果,搜索用时 15 毫秒
81.
Emmanouil Amolochitis Ioannis T. Christou Zheng-Hua Tan Ramjee Prasad 《Information processing & management》2013
We present PubSearch, a hybrid heuristic scheme for re-ranking academic papers retrieved from standard digital libraries such as the ACM Portal. The scheme is based on the hierarchical combination of a custom implementation of the term frequency heuristic, a time-depreciated citation score and a graph-theoretic computed score that relates the paper’s index terms with each other. We designed and developed a meta-search engine that submits user queries to standard digital repositories of academic publications and re-ranks the repository results using the hierarchical heuristic scheme. We evaluate our proposed re-ranking scheme via user feedback against the results of ACM Portal on a total of 58 different user queries specified from 15 different users. The results show that our proposed scheme significantly outperforms ACM Portal in terms of retrieval precision as measured by most common metrics in Information Retrieval including Normalized Discounted Cumulative Gain (NDCG), Expected Reciprocal Rank (ERR) as well as a newly introduced lexicographic rule (LEX) of ranking search results. In particular, PubSearch outperforms ACM Portal by more than 77% in terms of ERR, by more than 11% in terms of NDCG, and by more than 907.5% in terms of LEX. We also re-rank the top-10 results of a subset of the original 58 user queries produced by Google Scholar, Microsoft Academic Search, and ArnetMiner; the results show that PubSearch compares very well against these search engines as well. The proposed scheme can be easily plugged in any existing search engine for retrieval of academic publications. 相似文献
82.
随着信息高速公路的发展 ,Internet与化学研究、教学的联系日益紧密 ,本文从Internet所提供的几种主要服务入手 ,简要地介绍了化学工作者如何利用Internet进行国内、国际间学术的交流和讨论 ,以及因此而给化学研究、教学带来的巨大推动力 相似文献
83.
Web数据挖掘在搜索引擎中的应用 总被引:1,自引:0,他引:1
分析了搜索引擎的结构组成,从Web的结构挖掘、内容挖掘、使用挖掘3方面对Web挖掘在搜索引擎中的应用进行阐述。 相似文献
84.
论文提出了围绕线索深度挖掘,从而找到高质量国外网络教学资源的方法:即了解国外网络教学资源的各种特征,选择合适的搜索引擎作为检索工具,结合搜索引擎的高级语法,对初步检索结果进行分析推理。 相似文献
85.
Mike Thelwall 《Journal of Informetrics》2012,6(1):44-52
In May 2011 the Bing Search API 2.0 had become the only major international web search engine data source available for automatic offline processing for webometric research. This article describes its key features, contrasting them with previous web search data sources, and discussing implications for webometric research. Overall, it seems that large-scale quantitative web research is possible with the Bing Search API 2.0, including query splitting, but that legal issues require the redesign of webometric software to ensure that all results obtained from Bing are displayed directly to the user. 相似文献
86.
对于复杂人脸模式、脸部特征的提取,是人脸自动识别技术的关键,本文对固定背景下人脸图像特征的定位和提取算法进行了分析.文中首先对彩色图像背景进行分割,得到二值化图像;然后采用边界搜索方法确定人脸外接矩形;最后在色度空间中,结合SUSAN角点检测方法,实现人眼、嘴角定位,完成了人脸图像特征的提取和识别.实验证明,该算法在降低运算区域的同时,降低了运算复杂度和其他干扰因素,并且在速度、效率、准确性方面均有良好的性能. 相似文献
87.
崔新华 《贵阳学院学报(自然科学版)》2012,7(3)
在网络信息检索发展的过程中,研究者们不断尝试着将自然语言处理应用到网络信息检索里,希望能为检索效果提高带来帮助。本文介绍自然语言处理的相关技术和方法;然后提出面向用户的查询扩展统计模型中的用户兴趣模型;分析了中文自然语言处理在网络信息检索中的应用。 相似文献
88.
Michael Neubert 《Slavic & East European Information Resources》2013,14(1):53-62
ABSTRACT. Google is pursuing “mass digitization” of Russian books as part of its efforts that now involve more than a dozen partners, although so far there is no separate Russian‐language search interface. How easy is it to find materials in books.google.com that are in Russian? What do users need to know to maximize their results? 相似文献
89.
Beth Le Poire Ashley Duggan Carolyn Shepard Judee Burgoon 《Communication Research Reports》2013,30(3):195-206
Previous research suggests that individual nonverbal cues and cue complexes communicate multiple relational messages simultaneously. This work examines the contention that nonverbal percepts may predict relational message interpretations in romantic relationships. Results provide support for the hypothesis that nonverbal cues indicative of greater involvement, pleasantness, and expressiveness connote messages of intimacy. Specifically, the current study reveals that perceptions of intimacy and composure are associated with greater vocalic involvement. Interpretations are provided in line with the social meanings model. 相似文献
90.
Carmelita Pickett 《资料收集管理》2013,38(4):260-275
This study analyzes the coverage of black studies journals as compared to women's studies journals in Web of Science, Academic Search Complete, and ArticleFirst. This study also examines black studies bibliographies and directories to identify journals that are suitable for inclusion in Journal Citation Reports and consequently Web of Science and evaluates seven black studies journals using the Thomson Reuters journal selection process. 相似文献