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排序方式: 共有2085条查询结果,搜索用时 15 毫秒
71.
针对垂直搜索引擎研究领域的关键技术问题,提出了一个结合本体筛选和文本挖掘的垂直搜索引擎构建思想.首先探讨了作为研究基础的本体和文本挖掘技术,讨论了两者的作用;之后阐述了垂直搜索引擎构建的关键技术,包括基于本体筛选的智能搜索器、结合文本挖掘的网页信息分析及抽取、索引器及查询处理器的构造;最后,对提出的思想进行了实现验证,构造一个面向高校毕业生招聘的垂直搜索引擎原型. 相似文献
72.
屈泽明 《电脑编程技巧与维护》2008,(13):20-24
本文以C#为设计语言,应用ADO.NET技术,并且综合运用DataAdapter与DataSet,完成ASP.NET下DBF文件向MDB文件的转换,这样在应用系统中无需借助第三方软件的转换就可以直接使用DBF文件,解决了以MDB文件为数据源的应用系统如何直接使用DBF文件的问题。 相似文献
73.
在Web应用系统中经常会遇到文本处理的问题,如何在企业的Web管理系统中应用Word文档是系统用户关心的问题。通过在对Word对象的内容与格式及图表对象进行控制,提出了一种动态实现Word报告生成与下栽的方法。 相似文献
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76.
目前,语义Web服务匹配方面的研究主要集中在基于服务功能性信息的语义匹配上,但是,充分利用非功能语义信息有助于提高服务匹配的精度。非功能语义信息主要是文本描述,因此,基于非功能语义的服务匹配转化为文本相似度的问题。为了支持中文,本文根据《知网》来计算文本相似度,详细介绍了词语相似度、概念相似度和义原相似度的计算方法,并进行了实验,实验结果显示加入非功能语义虽然查全率有所下降,但查准率有很大的提高,进而证明非功能语义可以提高服务匹配的精度。 相似文献
77.
Text mining has become a major research topic in which text classification is the important task for finding the relevant information from the new document. Accordingly, this paper presents a semantic word processing technique for text categorization that utilizes semantic keywords, instead of using independent features of the keywords in the documents. Hence, the dimensionality of the search space can be reduced. Here, the Back Propagation Lion algorithm (BP Lion algorithm) is also proposed to overcome the problem in updating the neuron weight. The proposed text classification methodology is experimented over two data sets, namely, 20 Newsgroup and Reuter. The performance of the proposed BPLion is analysed, in terms of sensitivity, specificity, and accuracy, and compared with the performance of the existing works. The result shows that the proposed BPLion algorithm and semantic processing methodology classifies the documents with less training time and more classification accuracy of 90.9%. 相似文献
78.
Palaiahnakote Shivakumara Author Vitae Weihua Huang Author Vitae Author Vitae Chew Lim Tan Author Vitae 《Pattern recognition》2010,43(6):2165-2185
Detection of both scene text and graphic text in video images is gaining popularity in the area of information retrieval for efficient indexing and understanding the video. In this paper, we explore a new idea of classifying low contrast and high contrast video images in order to detect accurate boundary of the text lines in video images. In this work, high contrast refers to sharpness while low contrast refers to dim intensity values in the video images. The method introduces heuristic rules based on combination of filters and edge analysis for the classification purpose. The heuristic rules are derived based on the fact that the number of Sobel edge components is more than the number of Canny edge components in the case of high contrast video images, and vice versa for low contrast video images. In order to demonstrate the use of this classification on video text detection, we implement a method based on Sobel edges and texture features for detecting text in video images. Experiments are conducted using video images containing both graphic text and scene text with different fonts, sizes, languages, backgrounds. The results show that the proposed method outperforms existing methods in terms of detection rate, false alarm rate, misdetection rate and inaccurate boundary rate. 相似文献
79.
In knowledge discovery in a text database, extracting and returning a subset of information highly relevant to a user's query is a critical task. In a broader sense, this is essentially identification of certain personalized patterns that drives such applications as Web search engine construction, customized text summarization and automated question answering. A related problem of text snippet extraction has been previously studied in information retrieval. In these studies, common strategies for extracting and presenting text snippets to meet user needs either process document fragments that have been delimitated a priori or use a sliding window of a fixed size to highlight the results. In this work, we argue that text snippet extraction can be generalized if the user's intention is better utilized. It overcomes the rigidness of existing approaches by dynamically returning more flexible start-end positions of text snippets, which are also semantically more coherent. This is achieved by constructing and using statistical language models which effectively capture the commonalities between a document and the user intention. Experiments indicate that our proposed solutions provide effective personalized information extraction services. 相似文献
80.
Yu-Ting Pai Author VitaeAuthor Vitae Shanq-Jang Ruan Author Vitae 《Pattern recognition》2010,43(9):3177-3187
Document image binarization involves converting gray level images into binary images, which is a feature that has significantly impacted many portable devices in recent years, including PDAs and mobile camera phones. Given the limited memory space and the computational power of portable devices, reducing the computational complexity of an embedded system is of priority concern. This work presents an efficient document image binarization algorithm with low computational complexity and high performance. Integrating the advantages of global and local methods allows the proposed algorithm to divide the document image into several regions. A threshold surface is then constructed based on the diversity and the intensity of each region to derive the binary image. Experimental results demonstrate the effectiveness of the proposed method in providing a promising binarization outcome and low computational cost. 相似文献