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1.
针对基于图的多文档摘要,该文提出了一种在图排序中结合维基百科实体信息增强摘要质量的方法。首先抽取文档集合中高频实体的维基词条内容作为该文档集合的背景知识,然后采用PageRank算法对文档集合中的句子进行排序,之后采用改进的DivRank算法对文档集合和背景知识中的句子一起排序,最后根据两次排序结果的线性组合确定文档句子的最终排序以进行摘要句的选取。在DUC2005数据集上的评测结果表明该方法可以有效利用维基百科知识增强摘要的质量。  相似文献   

2.
提出了基于LDA(latent Dirichlet allocation)重要主题的多文档自动摘要算法。该算法与已有的基于主题模型的多文档自动摘要算法主要有两点区别:第一,在计算句子主题与文档主题相似度问题上,引入并定义了主题重要性的概念,将LDA模型建立的主题分成重要和非重要主题两类,计算句子权重时重点考虑句子主题和文档重要主题的相似性;第二,该方法同时使用句子的词频、位置等统计特征和LDA特征组成的向量计算句子的权重,既突出了传统的统计特征的显著优势,又结合了LDA模型的主题概念。实验表明,该算法在DUC2002标准数据集上取得了较好的摘要效果。  相似文献   

3.
应用图模型来研究多文档自动摘要是当前研究的一个热点,它以句子为顶点,以句子之间相似度为边的权重构造无向图结构。由于此模型没有充分考虑句子中的词项权重信息以及句子所属的文档信息,针对这个问题,该文提出了一种基于词项—句子—文档的三层图模型,该模型可充分利用句子中的词项权重信息以及句子所属的文档信息来计算句子相似度。在DUC2003和DUC2004数据集上的实验结果表明,基于词项—句子—文档三层图模型的方法优于LexRank模型和文档敏感图模型。  相似文献   

4.
一种新的句子相似度度量及其在文本自动摘要中的应用   总被引:7,自引:0,他引:7  
本文提出了一种新的句子相似度度量的方法并应用于文本自动摘要中。其创新处在于相似度计算不仅考虑句子中的unigram ,还考虑了bi-gram 和tri-gram ,通过回归方法将这几种相似度结果综合起来。实验证明这种相似度计算方法是有效的。同时本文还提出了一种新的,利用句子间相似度以及句子的权重的抽句 式文摘算法,在抽取出句子的同时也去掉了冗余。DUC2003、DUC2004 (Document Understanding Conference 2003 ,2004) 的评测结果征明了方法的有效性。我们的系统在DUC2004 的评测中列第二位。  相似文献   

5.
抽取式摘要的核心问题在于合理地建模句子,正确地判断句子重要性。该文提出一种计算句子话题重要性的方法,通过分析句子与话题的语义关系,判断句子是否描述话题的重要信息。针对自动摘要任务缺乏参考摘要作为训练数据的问题,该文提出一种基于排序学习的半监督训练框架,利用大规模未标注新闻语料训练模型。在DUC2004多文档摘要任务上的实验结果表明,该文提出的话题重要性特征能够作为传统启发式特征的有效补充,改进摘要质量。  相似文献   

6.
黄丽雯  钱微 《计算机应用》2006,26(11):2626-2627,2630
提出了一种对HITS算法进行改进的新方法,本方法将文档内容与一些启发信息如“短语”,“句子长度”和“首句优先”等结合,用于发现多文档子主题,并且将文档子主题特征转换成图节点进行排序。通过对DUC2004数据的实验,结果显示本方法是一种有效的多文本摘要方法。  相似文献   

7.
王金宝 《计算机应用》2006,26(5):1099-1101
为了适应实时在线的网络信息过滤需求,提出了一种新的自适应过滤模型。在系统的初始化阶段,运用增量学习方法对附加的少量伪相关文档进行学习,采用改进的文档词频方法来抽取特征词,以此扩展需求模板,提高模板准确度。在系统测试阶段,以系统效能指标最优为目标,提出了将概率模型和文档正例分布统计方法相结合来实现阈值优化的新算法。  相似文献   

8.
针对现有多文档抽取方法不能很好地利用句子主题信息和语义信息的问题,提出一种融合多信息句子图模型的多文档摘要抽取方法。首先,以句子为节点,构建句子图模型;然后,将基于句子的贝叶斯主题模型和词向量模型得到的句子主题概率分布和句子语义相似度相融合,得到句子最终的相关性,结合主题信息和语义信息作为句子图模型的边权重;最后,借助句子图最小支配集的摘要方法来描述多文档摘要。该方法通过融合多信息的句子图模型,将句子间的主题信息、语义信息和关系信息相结合。实验结果表明,该方法能够有效地改进抽取摘要的综合性能。  相似文献   

9.
基于语义的单文档自动摘要算法   总被引:1,自引:0,他引:1  
章芝青 《计算机应用》2010,30(6):1673-1675
单文档自动摘要的目的是在原始的文本中通过摘取、提炼主要信息,提供一篇简洁全面的摘要。自动摘要的主流方法是通过统计和机器学习的技术从文本中直接提取出句子,而单文档由于篇章有限,统计的方法无效。针对此问题,提出了基于语义的单文本自动摘要方法。该方法首先将文档划分为句子,然后计算每一对句子的语义相似度,通过运用改进型K-Medoids聚类算法将相似的句子归类,在每一类中选出最具代表性的句子,最后将句子组成文档摘要。实验结果表明,通过融合语义信息,该方法提高了摘要的质量。  相似文献   

10.
《计算机工程》2017,(8):219-224
为了在大量的新闻中快速找到自己感兴趣的内容,提出在单文档中基于加权TextRank算法提取主题句的方法,以得到新闻关键事件信息。通过计算新闻文本句子关键词的互信息值,对新闻报道进行事件句和非事件句的分类,过滤出非事件句。基于TextRank算法的思想,构建一个事件句有向图,引入句子位置、句子相似度和关键词覆盖频率3个影响因子,以此计算句子之间的影响权重,利用TextRank模型对图中的每个点计算权重,并选取排序最靠前的句子作为关键事件的主题句。实验结果表明,该方法的抽取效果优于基于词频-逆文档概率和新闻标题的主题句抽取方法。  相似文献   

11.
Multi-document summarization is the process of extracting salient information from a set of source texts and present that information to the user in a condensed form. In this paper, we propose a multi-document summarization system which generates an extractive generic summary with maximum relevance and minimum redundancy by representing each sentence of the input document as a vector of words in Proper Noun, Noun, Verb and Adjective set. Five features, such as TF_ISF, Aggregate Cross Sentence Similarity, Title Similarity, Proper Noun and Sentence Length associated with the sentences, are extracted, and scores are assigned to sentences based on these features. Weights that can be assigned to different features may vary depending upon the nature of the document, and it is hard to discover the most appropriate weight for each feature, and this makes generation of a good summary a very tough task without human intelligence. Multi-document summarization problem is having large number of decision parameters and number of possible solutions from which most optimal summary is to be generated. Summary generated may not guarantee the essential quality and may be far from the ideal human generated summary. To address this issue, we propose a population-based multicriteria optimization method with multiple objective functions. Three objective functions are selected to determine an optimal summary, with maximum relevance, diversity, and novelty, from a global population of summaries by considering both the statistical and semantic aspects of the documents. Semantic aspects are considered by Latent Semantic Analysis (LSA) and Non Negative Matrix Factorization (NMF) techniques. Experiments have been performed on DUC 2002, DUC 2004 and DUC 2006 datasets using ROUGE tool kit. Experimental results show that our system outperforms the state of the art works in terms of Recall and Precision.  相似文献   

12.
This paper proposes an optimization-based model for generic document summarization. The model generates a summary by extracting salient sentences from documents. This approach uses the sentence-to-document collection, the summary-to-document collection and the sentence-to-sentence relations to select salient sentences from given document collection and reduce redundancy in the summary. To solve the optimization problem has been created an improved differential evolution algorithm. The algorithm can adjust crossover rate adaptively according to the fitness of individuals. We implemented the proposed model on multi-document summarization task. Experiments have been performed on DUC2002 and DUC2004 data sets. The experimental results provide strong evidence that the proposed optimization-based approach is a viable method for document summarization.  相似文献   

13.
In this paper, we have presented an optimization approach to document summarization. The potential of optimization based document summarization models has not been well explored to date. This is partially the difficulty to formulate the criteria used for objective assessment. We modeled document summarization as the linear and nonlinear optimization problems. These models generally attempt simultaneously to balance coverage and diversity in the summary. To solve the optimization problem we developed a novel particle swarm optimization (PSO) algorithm. Experiments showed our linear and nonlinear models produce very competitive results, which significantly outperform the NIST baselines in both years. More important, although linear and nonlinear models are comparable to the top three systems S24, S15, and S12 in the DUC2006, they are even superior to the best participating system in the DUC2005.  相似文献   

14.
This paper proposes a constraint-driven document summarization approach emphasizing the following two requirements: (1) diversity in summarization, which seeks to reduce redundancy among sentences in the summary and (2) sufficient coverage, which focuses on avoiding the loss of the document’s main information when generating the summary. The constraint-driven document summarization models with tuning the constraint parameters can drive content coverage and diversity in a summary. The models are formulated as a quadratic integer programming (QIP) problem. To solve the QIP problem we used a discrete PSO algorithm. The models are implemented on multi-document summarization task. The comparative results showed that the proposed models outperform other methods on DUC2005 and DUC2007 datasets.  相似文献   

15.
With the rapid growth of information on the Internet and electronic government recently, automatic multi-document summarization has become an important task. Multi-document summarization is an optimization problem requiring simultaneous optimization of more than one objective function. In this study, when building summaries from multiple documents, we attempt to balance two objectives, content coverage and redundancy. Our goal is to investigate three fundamental aspects of the problem, i.e. designing an optimization model, solving the optimization problem and finding the solution to the best summary. We model multi-document summarization as a Quadratic Boolean Programing (QBP) problem where the objective function is a weighted combination of the content coverage and redundancy objectives. The objective function measures the possible summaries based on the identified salient sentences and overlap information between selected sentences. An innovative aspect of our model lies in its ability to remove redundancy while selecting representative sentences. The QBP problem has been solved by using a binary differential evolution algorithm. Evaluation of the model has been performed on the DUC2002, DUC2004 and DUC2006 data sets. We have evaluated our model automatically using ROUGE toolkit and reported the significance of our results through 95% confidence intervals. The experimental results show that the optimization-based approach for document summarization is truly a promising research direction.  相似文献   

16.
Text summarization is a process of extracting salient information from a source text and presenting that information to the user in a condensed form while preserving its main content. In the text summarization, most of the difficult problems are providing wide topic coverage and diversity in a summary. Research based on clustering, optimization, and evolutionary algorithm for text summarization has recently shown good results, making this a promising area. In this paper, for a text summarization, a two‐stage sentences selection model based on clustering and optimization techniques, called COSUM, is proposed. At the first stage, to discover all topics in a text, the sentences set is clustered by using k‐means method. At the second stage, for selection of salient sentences from clusters, an optimization model is proposed. This model optimizes an objective function that expressed as a harmonic mean of the objective functions enforcing the coverage and diversity of the selected sentences in the summary. To provide readability of a summary, this model also controls length of sentences selected in the candidate summary. For solving the optimization problem, an adaptive differential evolution algorithm with novel mutation strategy is developed. The method COSUM was compared with the 14 state‐of‐the‐art methods: DPSO‐EDASum; LexRank; CollabSum; UnifiedRank; 0–1 non‐linear; query, cluster, summarize; support vector machine; fuzzy evolutionary optimization model; conditional random fields; MA‐SingleDocSum; NetSum; manifold ranking; ESDS‐GHS‐GLO; and differential evolution, using ROUGE tool kit on the DUC2001 and DUC2002 data sets. Experimental results demonstrated that COSUM outperforms the state‐of‐the‐art methods in terms of ROUGE‐1 and ROUGE‐2 measures.  相似文献   

17.
Due to the exponential growth of textual information available on the Web, end users need to be able to access information in summary form – and without losing the most important information in the document when generating the summaries. Automatic generation of extractive summaries from a single document has traditionally been given the task of extracting the most relevant sentences from the original document. The methods employed generally allocate a score to each sentence in the document, taking into account certain features. The most relevant sentences are then selected, according to the score obtained for each sentence. These features include the position of the sentence in the document, its similarity to the title, the sentence length, and the frequency of the terms in the sentence. However, it has still not been possible to achieve a quality of summary that matches that performed by humans and therefore methods continue to be brought forward that aim to improve on the results. This paper addresses the generation of extractive summaries from a single document as a binary optimization problem where the quality (fitness) of the solutions is based on the weighting of individual statistical features of each sentence – such as position, sentence length and the relationship of the summary to the title, combined with group features of similarity between candidate sentences in the summary and the original document, and among the candidate sentences of the summary. This paper proposes a method of extractive single-document summarization based on genetic operators and guided local search, called MA-SingleDocSum. A memetic algorithm is used to integrate the own-population-based search of evolutionary algorithms with a guided local search strategy. The proposed method was compared with the state of the art methods UnifiedRank, DE, FEOM, NetSum, CRF, QCS, SVM, and Manifold Ranking, using ROUGE measures on the datasets DUC2001 and DUC2002. The results showed that MA-SingleDocSum outperforms the state of the art methods.  相似文献   

18.
Multi‐document summarization is a process of automatic creation of a compressed version of a given collection of documents that provides useful information to users. In this article we propose a generic multi‐document summarization method based on sentence clustering. We introduce five clustering methods, which optimize various aspects of intra‐cluster similarity, inter‐cluster dissimilarity and their combinations. To solve the clustering problem a modification of discrete particle swarm optimization algorithm has been proposed. The experimental results on open benchmark data sets from DUC2005 and DUC2007 show that our method significantly outperforms the baseline methods for multi‐document summarization.  相似文献   

19.
In paper, we propose an unsupervised text summarization model which generates a summary by extracting salient sentences in given document(s). In particular, we model text summarization as an integer linear programming problem. One of the advantages of this model is that it can directly discover key sentences in the given document(s) and cover the main content of the original document(s). This model also guarantees that in the summary can not be multiple sentences that convey the same information. The proposed model is quite general and can also be used for single- and multi-document summarization. We implemented our model on multi-document summarization task. Experimental results on DUC2005 and DUC2007 datasets showed that our proposed approach outperforms the baseline systems.  相似文献   

20.
针对锌电解过程能耗过高的情况,研究其能耗优化问题.根据电力部门实行的分时计价政策,建立以全天锌电解过程电能消耗和总用电费用为目标的锌电解过程多目标优化模型.提出一种带加速度调整的粒子群优化算法,当粒子陷入局部最优时,通过加速度策略增强种群速度,使算法获得持续搜索的能力,有效克服早熟收敛;并和Powell算法相结合构成新的混合粒子群算法,将粒子群算法的全局搜索能力与Powell算法的局部寻优能力有机结合起来.最后将该混合粒子群算法应用于所建优化模型的求解,获得优化生产方案.仿真结果证明了该算法的有效性.工业应用效果表明,按所得优化方案组织生产降低了电能消耗,减少了用电费用.  相似文献   

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