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As the information on the Internet dramatically increases, more and more limitations in information searching are revealed, because web pages are designed for human use by mixing content with presentation. In order to overcome these limitations, the Semantic Web, based on ontology, was introduced by W3C to bring about significant advancement in web searching. To accomplish this, the Semantic Web must provide search methods based on the different relationships between resources.In this paper, we propose a semantic association search methodology that consists of the evaluation of resources and relationships between resources, as well as the identification of relevant information based on ontology, a semantic network of resources and properties. The proposed semantic search method is based on an extended spreading activation technique. In order to evaluate the importance of a query result, we propose weighting methods for measuring properties and resources based on their specificity and generality. From this work, users can search semantically associated resources for their query, confident that the information is valuable and important. The experimental results show that our method is valid and efficient for searching and ranking semantic search results.  相似文献   

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An increasing amount of structured data on the Web has attracted industry attention and renewed research interest in what is collectively referred to as semantic search. These solutions exploit the explicit semantics captured in structured data such as RDF for enhancing document representation and retrieval, or for finding answers by directly searching over the data. These data have been used for different tasks and a wide range of corresponding semantic search solutions have been proposed in the past. However, it has been widely recognized that a standardized setting to evaluate and analyze the current state-of-the-art in semantic search is needed to monitor and stimulate further progress in the field. In this paper, we present an evaluation framework for semantic search, analyze the framework with regard to repeatability and reliability, and report on our experiences on applying it in the Semantic Search Challenge 2010 and 2011.  相似文献   

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Explicit icon semantics can reduce the difficulty of understanding complex visual information. Optimizing the icon semantics and text semantics of icons can effectively improve the cognitive performance of digital interfaces. This paper adopts visual search tasks to study the effects of different combinations of icon semantic familiarity and the presence or absence of text on icon search performance under horizontal and vertical layouts. The behavioral experiment results show that under two layouts: 1. The main effect of icon semantics is significant, and the search performance increases with the increase of semantic familiarity. 2. The main effect of text is significant, and the search performance is negatively correlated with the addition of text. The eye movement experiment found that the semantic familiarity of icons had a significant impact on average fixation time. Furthermore, the number of fixation points changed significantly after the text variable was added. Therefore, there was no significant difference in the number of fixation points in the horizontal layout, and icon semantics was the main influencing factor in visual search. In the vertical layout, there was no significant difference in average fixation time, and text was the main influencing factor of visual search. The results show that the semantic familiarity of icons and different combinations with or without text significantly affect visual search performance in horizontal and vertical layouts. This paper provides a theoretical reference for the combination of icons and text in interface design.  相似文献   

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语义Web搜索技术研究进展   总被引:3,自引:3,他引:3  
语义Web搜索技术是综合本体论、信息检索、自然语言处理等多学科理论和方法的新兴技术。介绍了语义Web和语义Web搜索的现状。在此基础上,给出了实现语义Web搜索技术的一般体系结构,并进一步分析了各组成模块的基本任务、现有技术和评价体系。最后给出了所做的相关工作和对语义Web搜索技术的展望。  相似文献   

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陈海燕 《计算机科学》2015,42(1):261-267
词汇语义相似度的计算在网页浏览和查询推荐等网络相关工作中起着重要的作用.传统的基于分类的方法不能处理持续出现的新词.由于网络数据中隐藏着大量的噪音和冗余,鲁棒性和准确性仍然是一个挑战,因此提出了一种基于搜索引擎的词汇语义相似度计算方法.语义片段和检索结果的页数被用来去除词汇语义相似度计算过程中的噪音和冗余.此外,还提出了一种方法来整合查询结果页数、语义片段和显示的搜索结果的数量,该方法不需要任何先验知识与本体.实验结果显示,所提出的方法在Rubenstein-Goodenough测试集的相关系数为0.851,优于现有的基于网络的词汇语义相似度计算方法,同时在搜索引擎的查询扩展任务中具有较为良好的应用效果.  相似文献   

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The current web IR system retrieves relevant information only based on the keywords which is inadequate for that vast amount of data. It provides limited capabilities to capture the concepts of the user needs and the relation between the keywords. These limitations lead to the idea of the user conceptual search which includes concepts and meanings. This study deals with the Semantic Based Information Retrieval System for a semantic web search and presented with an improved algorithm to retrieve the information in a more efficient way.This architecture takes as input a list of plain keywords provided by the user and the query is converted into semantic query. This conversion is carried out with the help of the domain concepts of the pre-existing domain ontologies and a third party thesaurus and discover semantic relationship between them in runtime. The relevant information for the semantic query is retrieved and ranked according to the relevancy with the help of an improved algorithm. The performance analysis shows that the proposed system can improve the accuracy and effectiveness for retrieving relevant web documents compared to the existing systems.  相似文献   

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语义搜索研究综述   总被引:2,自引:0,他引:2  
语义搜索将语义Web技术引入搜索引擎,改善当前搜索引擎的搜索效果,近年来得到广泛关注.文章介绍了语义搜索领域的研究基础,包括研究现状和常用的研究方法,对语义搜索进行了分类研究和深入分析,语义搜索主要可分为基于传统搜索的增强型语义搜索和基于本体推理的知识型语义搜索;文章指出了语义搜索研究中存在的问题,并对未来开展语义搜索研究进行了总结和展望.  相似文献   

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基于高层语义的视频检索研究   总被引:1,自引:0,他引:1       下载免费PDF全文
视频语义检索的研究是目前研究的热点之一。现有的视频检索系统技术多是基于底层特征的、非语义层次的检索。与人类思维中所能理解的高层语义概念相去甚远,这严重影响视频检索的实际效果。如何跨越底层特征和高层语义的鸿沟,用高层语义概念进行视频检索是当前研究的重点。通过对视频内容的语义理解、语义分析、语义提取的简要概述,试图构造一种视频语义检索模型。  相似文献   

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Ranking plays important role in contemporary information search and retrieval systems. Among existing ranking algorithms, link analysis based algorithms have been proved to be effective for ranking documents retrieved from large-scale text repositories such as the current Web. Recent developments in semantic Web raise considerable interest in designing new ranking paradigms for various semantic search applications. While ranking methods in this context exist, they have not gained much popularity. In this article we introduce the idea of the “Rational Research” model which reflects search behaviour of a “rational” researcher in a scientific research environment, and propose the RareRank algorithm for ranking entities in semantic search systems, in particular, we focus on elaborating the rationale and implementation of the algorithm. Experiments are performed using the RareRank algorithm and the results are evaluated by domain experts using popular ranking performance measures. A comparison study with existing link-based ranking algorithms reveals the benefits of the proposed method.  相似文献   

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如何从大量信息中获取有用的信息,是目前面临的挑战性问题,在寻找有用信息的迫切性需求下,搜索引擎逐渐成为人们在网上检索信息的重要工具。通过对语义搜索的研究和设计,证明语义搜索引擎的可行性与实用性。总的来说,我们已经初步完成了一个基于语义的搜索引擎的框架结构,该框架包括搜索、检索、搜集等功能和模块,已经覆盖了该课题的多数研究内容和目标。其中的有一些技术已经可以在电子商务等一些专用领域应用了。  相似文献   

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Engineers create engineering documents with their own terminologies, and want to search existing engineering documents quickly and accurately during a product development process. Keyword-based search methods have been widely used due to their ease of use, but their search accuracy has been often problematic because of the semantic ambiguity of terminologies in engineering documents and queries. The semantic ambiguity can be alleviated by using a domain ontology. Also, if queries are expanded to incorporate the engineer’s personalized information needs, the accuracy of the search result would be improved. Therefore, we propose a framework to search engineering documents with less semantic ambiguity and more focus on each engineer’s personalized information needs. The framework includes four processes: (1) developing a domain ontology, (2) indexing engineering documents, (3) learning user profiles, and (4) performing personalized query expansion and retrieval. A domain ontology is developed based on product structure information and engineering documents. Using the domain ontology, terminologies in documents are disambiguated and indexed. Also, a user profile is generated from the domain ontology. By user profile learning, user’s interests are captured from the relevant documents. During a personalized query expansion process, the learned user profile is used to reflect user’s interests. Simultaneously, user’s searching intent, which is implicitly inferred from the user’s task context, is also considered. To retrieve relevant documents, an expanded query in which both user’s interests and intents are reflected is then matched against the document collection. The experimental results show that the proposed approach can substantially outperform both the keyword-based approach and the existing query expansion method in retrieving engineering documents. Reflecting a user’s information needs precisely has been identified to be the most important factor underlying this notable improvement.  相似文献   

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随着数字内容不断增长,信息检索技术已经不能满足不同用户对高精度信息内容获取的需求.文中提出基于多语义关系的个性化查询扩展方法,并应用于基于社会化标签的个性化搜索系统.模型使用标签-主题模型对用户兴趣模型进行建模,能够更有效地表达语义和提升搜索效果.在此基础上,进一步提出基于多语义关系的个性化查询扩展方法,利用社会化标签的多重语义特征进行扩展词的选择.在大规模真实社会化标签数据集上的实验表明,文中方法优于非个性化搜索及其它基于社会化标签系统的个性化查询扩展方法.  相似文献   

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充分挖掘微博短文本的语义以实现精准搜索是一项重要任务.由于微博文本内容具有稀疏性和语义局限性的特点,使得仅通过分析字面语义来进行短文本理解和相似性匹配的传统搜索方法受到了一定的限制.因此提出了一种社交与概念化语义结合的扩展搜索方法,通过挖掘社交网络独特的社交属性如#标签#、“@”和链接信息URL,对微博短文本实现进一步的社交语义扩展.该方法将文本字面分析获取的概念词语和社交关系中潜在的关联标签信息相结合,对短文本进行2种角度下的语义特征表示,实现了基于微博短文本语义充分理解的精准搜索.在微博数据集上的对比实验表明,与已有的扩展搜索方法相比所提方法能捕捉更多的语义特征,微博搜索的性能也得到了显著的提升.  相似文献   

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We seek to leverage an expert user's knowledge about how information is organized in a domain and how information is presented in typical documents within a particular domain-specific collection, to effectively and efficiently meet the expert's targeted information needs. We have developed the semantic components model to describe important semantic content within documents. The semantic components model for a given collection (based on a general understanding of the type of information needs expected) consists of a set of document classes, where each class has an associated set of semantic components. Each semantic component instance consists of segments of text about a particular aspect of the main topic of the document and may not correspond to structural elements in the document. The semantic components model represents document content in a manner that is complementary to full text and keyword indexing. This paper describes how the semantic components model can be used to improve an information retrieval system. We present experimental evidence from a large interactive searching study that compared the use of semantic components in a system with full text and keyword indexing, where we extended the query language to allow users to search using semantic components, to a base system that did not have semantic components. We evaluate the systems from a system perspective, where semantic components were shown to improve document ranking for precision-oriented searches, and from a user perspective. We also evaluate the systems from a session-based perspective, evaluating not only the results of individual queries but also the results of multiple queries during a single interactive query session.  相似文献   

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基于多模态信息挖掘融合的视频检索技术   总被引:1,自引:0,他引:1  
基于内容的多媒体检索特别是视频检索,由于多媒体数据本身具有复杂的语义,所以极大地提高了检索的难度.算法着眼于视频本身挖掘出充分的资源信息并且将这些信息加以融合来提高视频检索的性能.基于这种思想,提出一种多模态视频检索模型以及相应的手动式搜索和交互式搜索的算法方案.搜索策略在TRECVID视频检索比赛中取得了不错的成绩.  相似文献   

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语义视频检索综述   总被引:4,自引:1,他引:4  
视频内容检索是多媒体应用的一个活跃研究方向,现有的内容检索技术大多是基于低层次特征的。这些非语义的低层特征难以理解,与人思维中的高层语义概念相差甚远,严重影响视频内容检索系统的易用性。低层特征和高层语义概念间的语义鸿沟很难逾越。如何跨越语义鸿沟,用语义概念检索视频内容是目前基于内容视频检索最具挑战性的研究方向。本文介绍语义视频检索出现的背景,分析语义鸿沟出现的原因,对现有尝试跨越语义鸿沟的主要方法进行综述;评述了相关技术的优缺点,探讨了各方法将来可能的研究发展方向以及视频语义检索近期、长期可能的技术突破点。  相似文献   

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针对基于内容的图像检索系统的检索效率和精度的不足,提出了综合语义和轮廓特征的图像检索方法.以拐点作为控制点对图像的轮廓进行精确分段,利用边界跟踪法对图像进行轮廓特征提取,并以图像的语义和底层的轮廓特征作为图像检索的综合指标,将图像的主观语义和底层特征融合起来,提高了图像底层特征和高层语义之间的联系.通过对不同类型的图像进行检索,实验结果证明该算法对复杂图像检索的效率高、精度高,并具有稳定的检索性能.因此,具有很好的发展趋势.  相似文献   

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Internet is a common information space populated with many entities (e.g., Internet of Things) with different information system types. Each of them has its own context of how to build and process documents (e.g., form documents). This leads to heterogeneous documents in terms of syntax and semantics, which are difficult to make information fusion from one context to another. To resolve this problem, this paper uses semantic interoperability technique which consists of two automatic stages including consistent data understanding and reasonable data usage. To implement semantic interoperability, this paper proposes a novel automatic tabular document exchange (DocEx) framework comprised of a new tabular document model (TabDoc) and a semantic inference scheme to fit the two stages above respectively. In this TabDoc model, a new Tabular Document Language (DocLang) as a communication medium between users and devices is provided, which is not only an information representation language but also a rule language for semantic inference as well. Abstract sub-tree-based semantic relations constructing the logical structure of a tabular document are separated from their presentational structures, clarifying the relationship between semantic groups (e.g., a cell or a block) with the help of a common dictionary CONEX. Besides, this paper proposes a semantic inference algorithm (SIA) executing the inference procedure on received tabular documents created by a Table Designer system which integrates with SIA. Finally, the proposed framework is applied to the processing of flight ticket booking in a realistic e-business scenario. The results show that the proposed method in this paper improves the performance of information fusion among different information systems on the Internet.  相似文献   

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