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排序方式: 共有248条查询结果,搜索用时 15 毫秒
51.
[目的/意义] 为帮助读者从热点事件产生的海量微博报道中快速了解事件的来龙去脉,提高微博事件摘要的准确性和可读性,提出一种基于事件要素的多模型微博热点事件时间轴摘要提取方法。[方法/过程] 针对微博文本特征,结合主题模型(LDA)与互信息最大熵模型(MaRxEnt-MI)的特点提取事件摘要关键词,以微博传播价值和主题相关性为标准筛选微博,以时间-摘要关键词-摘要微博的形式生成时间轴摘要。[结果/结论] 利用人工标注的测试集,与传统的TextRank方法进行对比,F值提高8%-13%,内部测试表明摘要可读性提高明显。实验文本和测试集的数量及事件丰富度需要进一步扩展,应考虑更多的加权策略模型以提高摘要的准确性。实验结果及测试反馈表明,本文的方法能很好满足用户对热点事件摘要信息需求,提高微博摘要提取的准确率。 相似文献
52.
Annotation of the functions of genes and proteins is an essential step in genome analysis. Information extraction techniques
have been proposed to obtain the function information of genes and proteins in the biomedical literature. However, the performance
of most information extraction techniques of function annotation in the biomedical literature is not satisfactory due to the
large variability in the expression of concepts in the biomedical literature. This paper proposes a framework to improve the
gene function annotation in the literature by considering both the textual information in the literature and the functions
of genes with sequences similar to a target gene. The new framework collects multiple types of evidence as: (i) textual information
about gene functions by matching keywords of the gene functions; (ii) gene function information from the known functions of
genes with sequences similar to a target gene; and (iii) the prior probabilities of gene functions to be associated with an
arbitrary gene by mining the known gene functions from curated databases. A supervised learning method is utilized to obtain
the weights for combining the three types of evidence to assign appropriate Gene Ontology terms for target genes. Empirical
studies on two testbeds demonstrate that the combination of sequence similarity scores, function prior probabilities and textual
information improves the accuracy of gene function annotation in the literature. The F-measure scores obtained with the proposed framework are substantially higher than the scores of the solutions in prior research.
相似文献
Yi FangEmail: |
53.
Xiaojun Wan 《Information Retrieval》2008,11(1):25-49
In recent years graph-ranking based algorithms have been proposed for single document summarization and generic multi-document
summarization. The algorithms make use of the “votings” or “recommendations” between sentences to evaluate the importance
of the sentences in the documents. This study aims to differentiate the cross-document and within-document relationships between
sentences for generic multi-document summarization and adapt the graph-ranking based algorithm for topic-focused summarization.
The contributions of this study are two-fold: (1) For generic multi-document summarization, we apply the graph-based ranking
algorithm based on each kind of sentence relationship and explore their relative importance for summarization performance.
(2) For topic-focused multi-document summarization, we propose to integrate the relevance of the sentences to the specified
topic into the graph-ranking based method. Each individual kind of sentence relationship is also differentiated and investigated
in the algorithm. Experimental results on DUC 2002–DUC 2005 data demonstrate the great importance of the cross-document relationships
between sentences for both generic and topic-focused multi-document summarizations. Even the approach based only on the cross-document
relationships can perform better than or at least as well as the approaches based on both kinds of relationships between sentences.
相似文献
Xiaojun WanEmail: |
54.
目的展望化学二氧化锰(CMD)工业的发展趋势,方法综述CMD的制备、改性等方面的研究进展情况,介绍几种常见的CMD合成法,结果随着研究的深入,新的化学工艺不断出现,化学二氧化锰的性能会越来越好,并将接近或超越电解二氧化锰(EMD),结论CMD研究仍将是化学领域的热点之一. 相似文献
55.
Liu HY Wang G Wei K Pi XT Zhu L Zheng XL Wen ZY 《Journal of Zhejiang University. Science. B》2010,11(12):937-943
In clinical practice, examination of the hemorrhagic spot (HS) remains difficult. In this paper, we describe a remote controlled
capsule (RCC) micro-system with an automated, color-based sensor to identify and localize the HS of the gastrointestinal (GI)
tract. In vitro testing of the detecting sensor demonstrated that it was capable of discriminating mimetic intestinal fluid
(MIF) with and without the hemoglobin (Hb) when the concentration of Hb in MIF was above 0.05 g/ml. Therefore, this RCC system
is able to detect the relatively accurate location of the HS in the GI tract. 相似文献
56.
结合桂林医学院图书馆自主开发的生物医学OA(全称Open Access开放存取)期刊检索平台建设实践,论述基于ASP环境下该期刊数据库和检索平台的设计与实现,同时对该平台的维护、更新、安全性及发展前景进行阐述,为图书馆OA期刊检索平台建设,特别是中小学图书馆、社区图书馆、乡镇图书馆提供参考。 相似文献
57.
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
58.
Weighted consensus multi-document summarization 总被引:1,自引:0,他引:1
Multi-document summarization is a fundamental tool for document understanding and has received much attention recently. Given a collection of documents, a variety of summarization methods based on different strategies have been proposed to extract the most important sentences from the original documents. However, very few studies have been reported on aggregating different summarization methods to possibly generate better summary results. In this paper, we propose a weighted consensus summarization method to combine the results from single summarization systems. We evaluate and compare our proposed weighted consensus method with various baseline combination methods. Experimental results on DUC2002 and DUC2004 data sets demonstrate the performance improvement by aggregating multiple summarization systems, and our proposed weighted consensus summarization method outperforms other combination methods. 相似文献
59.
60.
本文分析了改革开放后我国体育教学价值研究的特点。这特点表现为三方面:体育理论研究中忽视体育价值研究、体育教学研究中很少关注教学价值、体育研究中价值与目标、功能关系模糊。在结合有关研究文章基础上。对体育教学价值研究进行反思。 相似文献