共查询到20条相似文献，搜索用时 139 毫秒
1.
Antonio Jimeno-Yepes Rafael Berlanga-Llavori Dietrich Rebholz-Schuhmann 《Information processing & management》2010
Ontologies are frequently used in information retrieval being their main applications the expansion of queries, semantic indexing of documents and the organization of search results. Ontologies provide lexical items, allow conceptual normalization and provide different types of relations. However, the optimization of an ontology to perform information retrieval tasks is still unclear. In this paper, we use an ontology query model to analyze the usefulness of ontologies in effectively performing document searches. Moreover, we propose an algorithm to refine ontologies for information retrieval tasks with preliminary positive results. 相似文献
2.
Internet已成为全球最丰富的数据源,数据类型繁杂且动态变化,如何从中快速准确地检索出用户所需要的信息是一个亟待解决的问题.传统的搜索引擎基于语法的方式进行搜索,缺乏语义信息,难以准确地表达用户的查询需求和被检索对象的文档语义,致使查准率和查全率较低且搜索范围有限.本文对现有的语义检索方法进行了研究,分析了其中存在的问题,在此基础上提出了一种基于领域的语义搜索引擎模型,结合语义Web技术,使用领域本体元数据模型对用户的查询进行语义化规范,依据领域本体模式抽取文档中的知识并RDF化,准确地表达了用户的查询语义和作为被查询对象的文档语义,可以大大提高检索的准确性和检索效率,详细地给出了模型的体系结构、基本功能和工作原理. 相似文献
3.
[目的/意义]近半个世纪以来,研究者在信息查询系统分面导航的设计和评价中积累了丰富的研究成果,但这些成果却一直处于分散杂乱状态,不能很好地指导信息查询系统的设计。[方法/过程]本文采用文献调查法和文献分析法,根据影响信息查询系统可用性的情境框架,从系统、任务、用户等方面对这些成果进行分析综合。[结果/结论]由此组织成一个支持信息查询系统分面导航设计的知识体系并就其设计提出相关建议。 相似文献
4.
为实现高校数字档案馆的智能化档案知识检索,文章提出建立基于本体论的数字档案馆知识检索模型(OKR-DA),模型采用J2EE的MVC体系结构,研发了知识本体管理、语义标注、知识推理、知识检索等功能模块。经过实验评测,对模型的查全率和查准率进行了性能分析,验证了该知识检索模型的可行性。 相似文献
5.
Jae-wook Ahn Peter Brusilovsky Jonathan Grady Daqing He Radu Florian 《Information processing & management》2010,46(4):383-402
The system presented in this article aims to improve information access through the use of semantic annotation utilizing a non-traditional approach. Instead of applying semantic annotations to enhance the internal information access mechanisms, we use them to empower the user of an information access system through an innovative named entity-based user interface – NameSieve. NameSieve was built to support an intelligence analyst during the process of exploratory search, an advanced type of search requiring multiple iterations of retrieval interleaved with browsing and analyzing the retrieved information. The proposed approach was implemented in the NameSieve system so that the system can transparently present a summary of search results in the form of entity “clouds.” Therefore, these clouds allow the analyst to further explore the results in a novel manner, acting together as a faceted browsing interface. We ran a user study (with ten subjects) to examine the effect of NameSieve, and the study results reported in the paper demonstrate that this new way of applying semantic annotation information was actively used and was evaluated positively by the subjects. It enabled the subjects to work more productively and bring back most relevant documents. 相似文献
6.
[目的/意义]文章的研究目的是探索科学论文的语义标注模式以满足科研人员快速获取细粒度科学知识的需求。[方法/过程]结合已有的概念模型,提出了一个聚焦于描述科学论文论证过程的语义标注框架,并利用该框架对一篇认知心理学科学论文进行了语义标注实验以验证其有效性。[结果/结论]以上述科学论文为例,利用该框架对其物理结构、论证过程、科学结论和实验过程进行了语义标注,以此构建细粒度的语义出版物,并在此基础上实现了对科学论文的细粒度内容的检索。[局限]如何对科学论文中的图片、表格和数据集进行语义标注,需要进一步研究。 相似文献
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8.
Fatemeh Lashkari Ebrahim Bagheri Ali A. Ghorbani 《Information processing & management》2019,56(3):733-755
Traditional information retrieval techniques that primarily rely on keyword-based linking of the query and document spaces face challenges such as the vocabulary mismatch problem where relevant documents to a given query might not be retrieved simply due to the use of different terminology for describing the same concepts. As such, semantic search techniques aim to address such limitations of keyword-based retrieval models by incorporating semantic information from standard knowledge bases such as Freebase and DBpedia. The literature has already shown that while the sole consideration of semantic information might not lead to improved retrieval performance over keyword-based search, their consideration enables the retrieval of a set of relevant documents that cannot be retrieved by keyword-based methods. As such, building indices that store and provide access to semantic information during the retrieval process is important. While the process for building and querying keyword-based indices is quite well understood, the incorporation of semantic information within search indices is still an open challenge. Existing work have proposed to build one unified index encompassing both textual and semantic information or to build separate yet integrated indices for each information type but they face limitations such as increased query process time. In this paper, we propose to use neural embeddings-based representations of term, semantic entity, semantic type and documents within the same embedding space to facilitate the development of a unified search index that would consist of these four information types. We perform experiments on standard and widely used document collections including Clueweb09-B and Robust04 to evaluate our proposed indexing strategy from both effectiveness and efficiency perspectives. Based on our experiments, we find that when neural embeddings are used to build inverted indices; hence relaxing the requirement to explicitly observe the posting list key in the indexed document: (a) retrieval efficiency will increase compared to a standard inverted index, hence reduces the index size and query processing time, and (b) while retrieval efficiency, which is the main objective of an efficient indexing mechanism improves using our proposed method, retrieval effectiveness also retains competitive performance compared to the baseline in terms of retrieving a reasonable number of relevant documents from the indexed corpus. 相似文献
9.
主要论述基于Ontology（本体）的政府知识库的信息检索技术。该技术有别于传统的全文检索技术,采用基于本体的技术来分析处理用户提交的查询请求,分析自然语言形式问题中的词法、语法、语义等信息,识别出问题的类别,得到一些关键词,并进行扩展。还可根据本体中领域词汇的关系对关键词进行扩展,并赋予不同的权值。然后将问题类别和带权值的关键词序列提交给系统的检索引擎进行后继的处理。 相似文献
10.
The nature of the task that leads a person to engage in information interaction, as well as of information seeking and searching tasks, have been shown to influence individuals’ information behavior. Classifying tasks in a domain has been viewed as a departure point of studies on the relationship between tasks and human information behavior. However, previous task classification schemes either classify tasks with respect to the requirements of specific studies or merely classify a certain category of task. Such approaches do not lead to a holistic picture of task since a task involves different aspects. Therefore, the present study aims to develop a faceted classification of task, which can incorporate work tasks and information search tasks into the same classification scheme and characterize tasks in such a way as to help people make predictions of information behavior. For this purpose, previous task classification schemes and their underlying facets are reviewed and discussed. Analysis identifies essential facets and categorizes them into Generic facets of task and Common attributes of task. Generic facets of task include Source of task, Task doer, Time, Action, Product, and Goal. Common attributes of task includes Task characteristics and User’s perception of task. Corresponding sub-facets and values are identified as well. In this fashion, a faceted classification of task is established which could be used to describe users’ work tasks and information search tasks. This faceted classification provides a framework to further explore the relationships among work tasks, search tasks, and interactive information retrieval and advance adaptive IR systems design. 相似文献
11.
针对网络邮票图像的特点,提出邮票领域本体构建方法。根据网络邮票图像的视觉特征和描述文本．利用本体描述其语义特征,通过自动图像标注技术构建邮票图像本体库,并构建网络邮票图像的语义检索系统。实验表明,该系统解决了网络图像基于关键字检索和基于内容检索中的语义缺失问题,具有较高的图像检索准确率。 相似文献
12.
Semantic annotation of images is an important step to support semantic information extraction and retrieval. However, in a multi-annotator environment, various types of conflicts such as converting, merging, and inference conflicts could arise during the annotation. We devised conflict detection patterns based on different data, ontology at different inference levels and proposed the corresponding automatic conflict resolution strategies. We also constructed a simple annotator model to decide whether to trust a given piece of annotation from a given annotator. Finally, we conducted experiments to compare the performance of the automatic conflict resolution approaches during the annotation of images in the celebrity domain by 62 annotators. The experiments showed that the proposed method improved 3/4 annotation accuracy with respect to a naïve annotation system. 相似文献
13.
排序算法的好坏很大程度上影响了搜索引擎的用户体验,尤其是近些年随着语义检索技术的发展,使其检索和排序的对象不仅仅局限于文档和网页,更包括了实体和关系等。在对现有研究与应用调研的基础上,对当前语义检索研究进行了综述,并按照排序的阶段将其分为实体排序、关系排序和本体文档排序,并详细阐述了每种排序算法的研究进展,最后指出,将用户的社会网络因素同已有的排序算法相结合,是未来语义排序的发展趋势之一。 相似文献
14.
A user’s single session with a Web search engine or information retrieval (IR) system may consist of seeking information on single or multiple topics, and switch between tasks or multitasking information behavior. Most Web search sessions consist of two queries of approximately two words. However, some Web search sessions consist of three or more queries. We present findings from two studies. First, a study of two-query search sessions on the AltaVista Web search engine, and second, a study of three or more query search sessions on the AltaVista Web search engine. We examine the degree of multitasking search and information task switching during these two sets of AltaVista Web search sessions. A sample of two-query and three or more query sessions were filtered from AltaVista transaction logs from 2002 and qualitatively analyzed. Sessions ranged in duration from less than a minute to a few hours. Findings include: (1) 81% of two-query sessions included multiple topics, (2) 91.3% of three or more query sessions included multiple topics, (3) there are a broad variety of topics in multitasking search sessions, and (4) three or more query sessions sometimes contained frequent topic changes. Multitasking is found to be a growing element in Web searching. This paper proposes an approach to interactive information retrieval (IR) contextually within a multitasking framework. The implications of our findings for Web design and further research are discussed. 相似文献
15.
科学工作流生命周期由服务组件的发现、解释、组合以及执行等流程组成,其中服务发现是关键。基于本体驱动的服务发现是科学工作流系统的核心功能,包括用于描述服务的本体构建,基于本体的领域/中间服务的语义注释以及基于语义注释的服务查询和组合。本文以生物信息学领域应用为例,阐述了生物信息学本体的功能构成,服务于生物信息学服务发现的领域/服务本体框架结构以及领域/服务本体的语义注释方式和模式。 相似文献
16.
【目的/意义】跨语言信息检索研究的目的即在消除因语言的差异而导致信息查询的困难,提高从大量纷繁
复杂的查找特定信息的效率。同时提供一种更加方便的途径使得用户能够使用自己熟悉的语言检索另外一种语
言文档。【方法/过程】本文通过对国内外跨语言信息检索的研究现状分析,介绍了目前几种查询翻译的方法,包括：
直接查询翻译、文献翻译、中间语言翻译以及查询—文献翻译方法,对其效果进行比较,然后阐述了跨语言检索关
键技术,对使用基于双语词典、语料库、机器翻译技术等产生的歧义性提出了解决方法及评价。【结果/结论】使用自
然语言处理技术、共现技术、相关反馈技术、扩展技术、双向翻译技术以及基于本体信息检索技术确保知识词典的
覆盖度和歧义性处理,通过对跨语言检索实验分析证明采用知识词典、语料库和搜索引擎组合能够提高查询效
率。【创新/局限】本文为了解决跨语言信息检索使用词典、语料库中词语缺乏的现象,提出通过搜索引擎从网页获
取信息资源来充实语料库中语句对不足的问题。文章主要针对中英文信息检索问题进行了探讨,解决方法还需要
进一步研究,如中文切词困难以及字典覆盖率低等严重影响检索的效率。 相似文献
17.
There are a number of combinatorial optimisation problems in information retrieval in which the use of local search methods are worthwhile. The purpose of this paper is to show how local search can be used to solve some well known tasks in information retrieval (IR), how previous research in the field is piecemeal, bereft of a structure and methodologically flawed, and to suggest more rigorous ways of applying local search methods to solve IR problems. We provide a query based taxonomy for analysing the use of local search in IR tasks and an overview of issues such as fitness functions, statistical significance and test collections when conducting experiments on combinatorial optimisation problems. The paper gives a guide on the pitfalls and problems for IR practitioners who wish to use local search to solve their research issues, and gives practical advice on the use of such methods. The query based taxonomy is a novel structure which can be used by the IR practitioner in order to examine the use of local search in IR. 相似文献
18.
数字图书馆是传统图书馆在信息时代的发展与完善,目前已成为用户获取信息的重要渠道,但由于采用基于关键词的信息检索,缺乏对用户查询语言的深层次理解和分析,难以满足实际的需要.笔者在分析数字图书馆中存在的一系列问题的基础上,融合本体技术构建了基于本体的数字图书馆语义检索模型,并详细阐述了模型中各个模块的主要功能及其实现策略.实验结果表明,该模型取得了很好的预期效果,显著提高了信息检索的效率、准确度和知识获取的深度与广度. 相似文献
19.
[目的/意义]基于知识图谱与分面检索能够实现健康信息的有效组织,解决其多源异构、专业知识门槛高、语义歧义等方面的问题,从而帮助用户降低专业性医疗知识的使用门槛,引导用户更快获取资源。[方法/过程]将知识图谱与分面检索相结合,构建基于医学知识图谱的慢性病在线医疗社区分面检索模型,主要包括分面体系构建、分面与焦点排序以及分面展现控制3个步骤,并以百度贴吧自闭症吧为数据来源对分面检索原型予以实现。[结果/结论]所构建的自闭症分面检索原型系统应用效果较好,提高了用户检索的效率与质量。提出的分面检索模型对完善健康信息服务等相关理论和方法具有一定推动作用。 相似文献
20.
用比TMDM更丰富的语义发现技术和现有研究方法,从信息查询动机、分面选择、原型结构、主题图探索等角度,对基于分面主题图探索式搜索分析。评价自动选择分面导航点,论证如何整合基于分面主题图探索式搜索功能,探讨用户如何在缺乏专业知识领域采用探索式搜索实现查询信息的目的。 相似文献