共查询到20条相似文献，搜索用时 27 毫秒
1.
数字图书馆在WWW上进行相应的信息展示与提供，基于HTML的文档标记使信息查寻遇到了很大的挑战。本文提出了基于XML的搜索引擎逻辑结构，并对其中的关键技术进行了研究，提出了对XML半结构化文档建立索引和查寻时采用的数据结构和算法，使得数字图书馆在WWW上开展深层次信息提供成为可能，并且也使图书馆原有的MARC信息资源能得到充分利用。 相似文献
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XML在信息检索中的应用初探 总被引：3，自引：1，他引：3
本文在分析XML的结构、体系、主要特点、功能的基础上，从文档能够用模式来分类、一些含糊不清的词汇可以用上下文来区分、检索提问可以使用丰富的数据类型、用结构上的临近代替物理上的临近来排列检索结果、将文献中的部分内容作为检索结果予以返回等方面探讨了XML在信息检索领域的应用。 相似文献
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Mouna Torjmen-Khemakhem Karen Pinel-Sauvagnat Mohand Boughanem 《Information processing & management》2013
Multimedia objects can be retrieved using their context that can be for instance the text surrounding them in documents. This text may be either near or far from the searched objects. Our goal in this paper is to study the impact, in term of effectiveness, of text position relatively to searched objects. The multimedia objects we consider are described in structured documents such as XML ones. The document structure is therefore exploited to provide this text position in documents. Although structural information has been shown to be an effective source of evidence in textual information retrieval, only a few works investigated its interest in multimedia retrieval. More precisely, the task we are interested in this paper is to retrieve multimedia fragments (i.e. XML elements having at least one multimedia object). Our general approach is built on two steps: we first retrieve XML elements containing multimedia objects, and we then explore the surrounding information to retrieve relevant multimedia fragments. In both cases, we study the impact of the surrounding information using the documents structure. 相似文献
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M. Mercedes Martínez-Gonzlez Pablo de la Fuente 《Information processing & management》2007,43(6):1808
References to parts of structured documents use their structure to locate the piece of document which is the reference target. On the other hand, XML has become an increasingly important language for structured documents. One of its most important related languages is XPath, the language that permits fragments of XML documents to be selected. In this article we present a methodology, and an application case, to automatically extract and solve references to fragments of structured documents. This approach combines structure manipulation and information extraction, to enhance reference extraction tools by improving the precision of the references extracted. We take advantage of XML markup to locate the position within the structure in which the references are found. The use of XPath, one of the most important XML related languages, for reference resolution is original: the resolution tool automatically builds XPath expressions. This proposal is inspired (and implemented) from our work with legislative documents. 相似文献
6.
The principle of polyrepresentation offers a theoretical framework for handling multiple contexts in information retrieval (IR). This paper presents an empirical laboratory study of polyrepresentation in restricted mode of the information space with focus on inter and intra-document features. The Cystic Fibrosis test collection indexed in the best match system InQuery constitutes the experimental setting. Overlaps between five functionally and/or cognitively different document representations are identified. Supporting the principle of polyrepresentation, results show that in general overlaps generated by three or four representations of different nature have higher precision than those generated from two representations or the single fields. This result pertains to both structured and unstructured query mode in best match retrieval, however, with the latter query mode demonstrating higher performance. The retrieval overlaps containing search keys from the bibliographic references provide the best retrieval performance and minor MeSH terms the worst. It is concluded that a highly structured query language is necessary when implementing the principle of polyrepresentation in a best match IR system because the principle is inherently Boolean. Finally a re-ranking test shows promising results when search results are re-ranked according to precision obtained in the overlaps whilst re-ranking by citations seems less useful when integrated into polyrepresentative applications. 相似文献
7.
《Information processing & management》2019,56(5):1753-1770
XML has become a universal standard for information exchange over the Web due to features such as simple syntax and extensibility. Processing queries over these documents has been the focus of several research groups. In fact, there is broad literature in efficient XML query processing which explore indexes, fragmentation techniques, etc. However, for answering complex queries, existing approaches mainly analyze information that is explicitly defined in the XML document. A few work investigate the use of Prolog to increase the query possibilities, allowing inference over the data content. This can cause a significant increase in the query possibilities and expressive power, allowing access to non-obvious information. However, this requires translating the XML documents into Prolog facts. But for regular queries (which do not require inference), is this a good alternative? What kind of queries could benefit from the Prolog translation? Can we always use Prolog engines to execute XML queries in an efficient way? There are many questions involved in adopting an alternative approach to run XML queries. In this work, we investigate this matter by translating XML queries into Prolog queries and comparing the query processing times using Prolog and native XML engines. Our work contributes by providing a set of heuristics that helps users to decide when to use Prolog engines to process a given XML query. In summary, our results show that queries that search elements by a key value or by its position (simple search) are more efficient when run in Prolog than in native XML engines. Also, queries over large datasets, or that searches for substrings perform better when run by native XML engines. 相似文献
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《Information processing & management》2005,41(3):457-473
Two probabilistic approaches to cross-lingual retrieval are in wide use today, those based on probabilistic models of relevance, as exemplified by INQUERY, and those based on language modeling. INQUERY, as a query net model, allows the easy incorporation of query operators, including a synonym operator, which has proven to be extremely useful in cross-language information retrieval (CLIR), in an approach often called structured query translation. In contrast, language models incorporate translation probabilities into a unified framework. We compare the two approaches on Arabic and Spanish data sets, using two kinds of bilingual dictionaries––one derived from a conventional dictionary, and one derived from a parallel corpus. We find that structured query processing gives slightly better results when queries are not expanded. On the other hand, when queries are expanded, language modeling gives better results, but only when using a probabilistic dictionary derived from a parallel corpus.We pursue two additional issues inherent in the comparison of structured query processing with language modeling. The first concerns query expansion, and the second is the role of translation probabilities. We compare conventional expansion techniques (pseudo-relevance feedback) with relevance modeling, a new IR approach which fits into the formal framework of language modeling. We find that relevance modeling and pseudo-relevance feedback achieve comparable levels of retrieval and that good translation probabilities confer a small but significant advantage. 相似文献
10.
In a hierarchical XML structure, surrounding elements form the context of an XML element. In document-oriented XML, the context is a part of the semantics of the element and augments its textual information. The process of taking the context of the element into account in element scoring is called contextualization. This study extends the concept of contextualization and presents a classification of contextualization models. In an XML collection, elements are of different granularity, i.e. lower level elements are shorter and carry less textual information. Thus, it seems credible that contextualization interacts differently with diverse elements. Even if it is known that contextualization leads to improved effectiveness in element retrieval, the improvement on different granularity levels has not been investigated. This study explores the effect of contextualization on these levels. Further, a parameterized framework for testing contextualization is presented. 相似文献
11.
Recently there is a growing interest in the data model and query processing for probabilistic XML data. There are many potential applications of probabilistic data, and the XML data model is suitable to represent hierarchical information and data uncertainty of different levels naturally. However, the previously proposed probabilistic XML data models and query processing techniques separate finding data matches with evaluating the probabilities of results. Therefore, they should repeatedly access the data and need to get full data of paths given in queries to calculate the probabilities of results. 相似文献
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Structured document retrieval makes use of document components as the basis of the retrieval process, rather than complete documents. The inherent relationships between these components make it vital to support users’ natural browsing behaviour in order to offer effective and efficient access to structured documents. This paper examines the concept of best entry points, which are document components from which the user can browse to obtain optimal access to relevant document components. It investigates at the types of best entry points in structured document retrieval, and their usage and effectiveness in real information search tasks. 相似文献
14.
Combining the evidence of different relevance feedback methods for information retrieval 总被引：2，自引：0，他引：2
Joon Ho Lee 《Information processing & management》1998,34(6):681-691
It has been known that retrieval effectiveness can be significantly improved by combining multiple evidence from different query or document representations, or multiple retrieval techniques. In this paper, we combine multiple evidence from different relevance feedback methods, and investigate various aspects of the combination. We first generate multiple query vectors for a given information problem in a fully automatic way by expanding an initial query vector with various relevance feedback methods. We then perform retrieval runs for the multiple query vectors, and combine the retrieval results. Experimental results show that combining the evidence of different relevance feedback methods can lead to substantial improvements of retrieval effectiveness. 相似文献
15.
Ian A. Macleod 《Information processing & management》1977,13(3):167-175
Among the problems associated with modern information retrieval systems is the lack of any systematic approach to the design of query language interfaces. In this paper we attempt to show how a relationally organised data base is well suited to bibliographic data management, and how, given such a relational organisation it is possible to construct an interface which separates the query language from the physical representation of the data base. It is also shown how such a query language organisation may be usefully interfaced to existing retrieval systems. Finally a query language for retrieval applications is proposed. 相似文献
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《Information processing & management》2003,39(3):391-402
We will explore various ways to apply query structuring in cross-language information retrieval. In the first test, English queries were translated into Finnish using an electronic dictionary, and were run in a Finnish newspaper database of 55,000 articles. Queries were structured by combining the Finnish translation equivalents of the same English query key using the syn-operator of the InQuery retrieval system. Structured queries performed markedly better than unstructured queries. Second, the effects of compound-based structuring using a proximity operator for the translation equivalents of query language compound components were tested. The method was not useful in syn-based queries but resulted in decrease in retrieval effectiveness. Proper names are often non-identical spelling variants in different languages. This allows n-gram based translation of names not included in a dictionary. In the third test, a query structuring method where the Boolean and-operator was used to assign more weight to keys translated through n-gram matching gave good results. 相似文献
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《Information processing & management》2001,37(3):459-484
Satisfying non-trivial information needs involves collecting information from multiple resources, and synthesizing an answer that organizes that information. Traditional recall/precision-oriented information retrieval focuses on just one phase of that process: how to efficiently and effectively identify documents likely to be relevant to a specific, focused query. The TREC Interactive Track has as its goal the location of documents that pertain to different instances of a query topic, with no reward for duplicated coverage of topic instances. This task is similar to the task of organizing answer components into a complete answer. Clustering and classification are two mechanisms for organizing documents into groups. In this paper, we present an ongoing series of experiments that test the feasibility and effectiveness of using clustering and classification as an aid to instance retrieval and, ultimately, answer construction. Our results show that users prefer such structured presentations of candidate result set to a list-based approach. Assessment of the structured organizations based on the subjective judgement of the experiment subjects suggests that the structured organization can be more effective; however, assessment based on objective judgements shows mixed results. These results indicate that a full determination of the success of the approach depends on assessing the quality of the final answers generated by users, rather than on performance during the intermediate stages of answer construction. 相似文献
18.
近年来,XML已成为信息表示、交换和发布的标准,因此,XML数据查询已成数据库(DB)和信息检索(IR)领域广发研究的问题。XML通常被视为一个标签树,常用的方法是近似查询。由于在用户查询通常有一定的关系约束出现,在分析了用户查询对XML元素和值关系约束之后,本文提出了使用关系约束近似提取XML元素的方法 相似文献
19.
How to merge and organise query results retrieved from different resources is one of the key issues in distributed information retrieval. Some previous research and experiments suggest that cluster-based document browsing is more effective than a single merged list. Cluster-based retrieval results presentation is based on the cluster hypothesis, which states that documents that cluster together have a similar relevance to a given query. However, while this hypothesis has been demonstrated to hold in classical information retrieval environments, it has never been fully tested in heterogeneous distributed information retrieval environments. Heterogeneous document representations, the presence of document duplicates, and disparate qualities of retrieval results, are major features of an heterogeneous distributed information retrieval environment that might disrupt the effectiveness of the cluster hypothesis. In this paper we report on an experimental investigation into the validity and effectiveness of the cluster hypothesis in highly heterogeneous distributed information retrieval environments. The results show that although clustering is affected by different retrieval results representations and quality, the cluster hypothesis still holds and that generating hierarchical clusters in highly heterogeneous distributed information retrieval environments is still a very effective way of presenting retrieval results to users. 相似文献
20.
Extensible Markup Language (XML) documents are associated with time in two ways: (1) XML documents evolve over time and (2) XML documents contain temporal information. The efficient management of the temporal and multi-versioned XML documents requires optimized use of storage and efficient processing of complex historical queries. This paper provides a comparative analysis of the various schemes available to efficiently store and query the temporal and multi-versioned XML documents based on temporal, change management, versioning, and querying support. Firstly, the paper studies the multi-versioning control schemes to detect, manage, and query change in dynamic XML documents. Secondly, it describes the storage structures used to efficiently store and retrieve XML documents. Thirdly, it provides a comparative analysis of the various commercial tools based on change management, versioning, collaborative editing, and validation support. Finally, the paper presents some future research and development directions for the multi-versioned XML documents. 相似文献