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1.
The objective of this study is to develop a knowledge-base framework for generatingcooperative answers to indirect queries. Anindirect query can be considered as a nonstandard database query in which a user did not specify explicitly the information request. In a cooperative query answering system, a user's indirect query should be answered with an informative response, either anaffirmative response or anegative response, which is generated on the basis of the inference of the user's information request and the reformulation of the users' indirect query.This paper presents methods for inferring users' intended actions, determining users' information requirements, and for automatically reformulating indirect queries into direct queries. The inference process is carried out on the basis of a user model, calluser action model, as well as the query context. Two kinds ofinformative responses, i.e.affirmative responses andnegative responses can be generated by arule-based approach.  相似文献   

2.
用户兴趣和行为的多样性使得为不同用户提供更符合其查询意图的搜索结果成为一个具有挑战性的任务.Web 2.0下的社会标签是用户为他们感兴趣的网页等对象进行标注行为的结果,用户用标签来描述自己感兴趣的话题.这些标签不但代表着用户的兴趣,而且是对网页承载信息的最好揭示.提出了面向用户查询意图的标签推荐方法,旨在把能够体现用户真正查询意图的标签选择出来.标签作为对查询关键词的补充,不仅可以弥补用户短查询的缺陷,而且可以根据标签与网页上曾被标注过的标签间的关系,更准确地判断用户查询意图与网页内容之间的相关度,从而把更符合用户查询兴趣的结果排在靠前的位置上.实验结果表明,该方法比现有的其他方法更有效,这也说明社会标注对更准确地捕捉用户真实查询意图确实有重要作用.  相似文献   

3.
This paper is concerned with information-seeking dialogues in a restricted domain (we consider a consultation system for a Computer Science Department, delivering information about the various tasks that the users may want to perform: for example, how to access the library, get information about the courses of the Department, etc.) and presents a framework where a plan recognition and a user modeling component are integrated to cooperate in the task of identifying the user's plans and goals. The focus of the paper is centered on the techniques used for building the user model and exploiting it in the determination of the user's intentions. For this task, we use stereotypes and we propose some inference rules for expanding the user model by inferring the user's beliefs from both the sentences s/he utters and the information stored in the plan library of the system, that describes the actions in the domain. Moreover, we introduce some disambiguation rules that are applied to the information in the user model for restricting the set of ambiguous hypotheses on the user's plans and goals to the most plausible ones. This also simplifies a further clarification dialogue if it is necessary for a precise identification of the user's intentions.  相似文献   

4.
提出将概念图引入查询扩展,从概念的层面上进行语义的扩展。使用概念图表示查询可以更准确地表明用户的查询意图,并在此基础上进行语义的扩展,通过这种方法给出的扩展查询更符合用户的查询意图。对用户查询进行基于概念图的查询扩展,并将结果与百度的相似查询进行了比较,证明基于概念图的查询扩展能更准确地把握用户的查询意图。  相似文献   

5.
OLAP系统基于查询结构的用户浏览引导   总被引:4,自引:0,他引:4  
联机分析处理(OLAP)系统是数据仓库主要的前端支持工具,在OLAP系统中用户以浏览的方式进行数据访问。通常,OLAP系统用户一般会有相对稳定的信息需求,而OLAP系统中查询的结构一定程度上反映了用户所关心的信息内容,因此,用户执行查询的结构也会保持一定的稳定性。以查询结构为基础,对OLAP系统用户的查询行为进行了分析,提出了一种建立OLAP系统用户轮廓文件的方法,并对如何根据轮廓文件对用户的行为进行预测,并进一步对用户的浏览进行引导的方法进行了探讨。以此为基础,当OLAP系统用户进行信息浏览时,可以在OLAP系统前端,对用户可能感兴趣的地方做出一定的标识,引导用户将要进行的浏览动作,使用户能轻松的完成信息搜索的工作。  相似文献   

6.
FLEX: a tolerant and cooperative user interface to databases   总被引:2,自引:0,他引:2  
FLEX a user interface to relational databases, can be used satisfactorily by users with different levels of expertise. FLEX is based on a formal query language, but is tolerant of incorrect input. It never rejects queries; instead, it adapts flexibility and transparently to their level of correctness and well-formedness, providing interpretations of corresponding accuracy and specificity. The most prominent design feature of FLEX is the smooth concatenation of several independent mechanisms, each capable of handling input of decreasing level of correctness and well-formedness. Each input is cascaded through this series of mechanisms until an interpretation is found. FLEX is also cooperative. It never delivers empty answers without explanation or assistance. By following up each failed query with a set of more general queries, FLEX determines whether an empty answer is genuine, in which case it suggests related queries that have nonempty answers, or whether it reflects erroneous presuppositions on the part of the user, in which case it then explains them  相似文献   

7.
This paper proposes a two-level P2P caching strategy for Web search queries. The design is suitable for a fully distributed service platform based on managed peer boxes (set-top-box or DSL/cable modem) located at the edge of the network, where both boxes and access bandwidth to those boxes are controlled and managed by an ISP provider. Our solution significantly reduces user query traffic going outside of the ISP provider to get query results from the respective Web search engine. Web users are usually very reactive to worldwide events which cause highly dynamic query traffic patterns leading to load imbalance across peers. Our solution contains a strategy to quickly ease imbalance on peers and spread communication flow among participating peers. Each peer maintains a local result cache used to keep the answers for queries originated in the peer itself and queries for which the peer is responsible for by contacting the Web search engine on-demand. When query traffic is predominantly routed to a few responsible peers our strategy replicates the role of “being responsible for” to neighboring peers so that they can absorb query traffic. This is a fairly slow and adaptive process that we call mid-term load balancing. To achieve a short-term fair distribution of queries we introduce a location cache in each peer which keeps pointers to peers that have already requested the same queries in the recent past. This lets these peers share their query answers with newly requesting peers. This process is fast as these popular queries are usually cached in the first DHT hop of a requesting peer which quickly tends to redistribute load among more and more peers.  相似文献   

8.
Modern search engines employ advanced techniques that go beyond the structures that strictly satisfy the query conditions in an effort to better capture the user intentions. In this work, we introduce a novel query paradigm that considers a user query as an example of the data in which the user is interested. We call these queries exemplar queries. We provide a formal specification of their semantics and show that they are fundamentally different from notions like queries by example, approximate queries and related queries. We provide an implementation of these semantics for knowledge graphs and present an exact solution with a number of optimizations that improve performance without compromising the result quality. We study two different congruence relations, isomorphism and strong simulation, for identifying the answers to an exemplar query. We also provide an approximate solution that prunes the search space and achieves considerably better time performance with minimal or no impact on effectiveness. The effectiveness and efficiency of these solutions with synthetic and real datasets are experimentally evaluated, and the importance of exemplar queries in practice is illustrated.  相似文献   

9.
It has been observed that queries over XML data sources are often unsatisfiable. Unsatisfiability may stem from several different sources, e.g., the user may be insufficiently familiar with the labels appearing the documents, or may not be intimately aware of the hierarchical structure of the documents. To deal with query and document mismatches, previous research has considered returning answers that maximally satisfy (in some sense) the query, instead of only returning strictly satisfying answers. However, this breaks the golden database rule that only strictly satisfying answers are returned when querying. Indeed, the relationship between the query and answers is no longer clear, when unsatisfying answers are returned. To reinstate the golden database rule, this article proposes a framework for automatically correcting queries over XML. This framework generates similar satisfiable queries, when the user query is unsatisfiable. The user can then choose a satisfiable query of interest, and receive exactly satisfying answers to this query.  相似文献   

10.
A model of an extended fuzzy relational database was proposed to accommodate uncertain and imprecise information. We use two supplementary measurements, satisfactory degree and extra degree, for determining the quality of answers to Select‐Project‐Join (SPJ) queries. The method of measurement determines how much satisfactory information is provided and how much truth information is required for a query. The answers to the query thus contain sure answers and maybe answers. The core of this study is the detailed discussion on the quality of answers in an extended fuzzy relation to query processing. © 2005 Wiley Periodicals, Inc. Int J Int Syst 20: 647–668, 2005.  相似文献   

11.
查询扩展可以有效地消除查询歧义,提高信息检索的准确率和召回率.通过挖掘用户日志中查询词和相关文档的连接关系,构造关联查询,并在此基础上提出一种从关联查询中提取查询扩展词的查询扩展方法.同时,还提出一种查询歧义的判别方法,该方法可以对查询词所表达的检索意图的模糊程度进行有效度量,也可以对查询词的检索性能进行预先估计.通过对查询歧义的度量来动态调整扩展词的长度,提高查询扩展模型的灵活性和适应能力.  相似文献   

12.
Evaluating refined queries in top-k retrieval systems   总被引:2,自引:0,他引:2  
In many applications, users specify target values for certain attributes/features without requiring exact matches to these values in return. Instead, the result is typically a ranked list of "top k" objects that best match the specified feature values. User subjectivity is an important aspect of such queries, i.e., which objects are relevant to the user and which are not depends on the perception of the user. Due to the subjective nature of top-k queries, the answers returned by the system to an user query often do not satisfy the users need right away, either because the weights and the distance functions associated with the features do not accurately capture the users perception or because the specified target values do not fully capture her information need or both. In such cases, the user would like to refine the query and resubmit it in order to get back a better set of answers. While there has been a lot of research on query refinement models, there is no work that we are aware of on supporting refinement of top-k queries efficiently in a database system. Done naively, each "refined" query can be treated as a "starting" query and evaluated from scratch. We explore alternative approaches that significantly improve the cost of evaluating refined queries by exploiting the observation that the refined queries are not modified drastically from one iteration to another. Our experiments over a real-life multimedia data set show that the proposed techniques save more than 80 percent of the execution cost of refined queries over the naive approach and is more than an order of magnitude faster than a simple sequential scan.  相似文献   

13.
针对用户查询语句中所使用的词语和语料库中使用的词语不完全相同的问题,该文提出了基于用户信息的信息检索效果提高策略。充分利用用户查询语句中所使用的词语,适当的进行查询扩展,以达到解决词语不匹配的矛盾。在NTCIR-4的测试语料集上的实验结果表明,该文的方法是有效的。  相似文献   

14.
Approximating query answering on RDF databases   总被引:1,自引:0,他引:1  
Database users may be frustrated by no answers returned when they pose a query on the database. In this paper, we study the problem of relaxing queries on RDF databases in order to acquire approximate answers. We address two problems in efficient query relaxation. First, to ensure the quality of answers, we compute the similarities between relaxed queries with regard to the user query and use them to score the potential relevant answers. Second, for obtaining top-k answers, we develop two algorithms. One is based on the best-first strategy and relaxed queries are executed in the ranking order. The batch based algorithm executes the relaxed queries as a batch and avoids unnecessary execution cost. At last, we implement and experimentally evaluate our approaches.  相似文献   

15.
Relaxation as a platform for cooperative answering   总被引:2,自引:1,他引:1  
Responses to queries posed by a user of a database do not always contain the information desired. Database answers to a query, although they may be logically correct, can sometimes be misleading. Research in the area of cooperative answering for databases and deductive databases seeks to rectify these problems. We introduce a cooperative method calledrelaxation for expanding deductive database and logic programming queries. The relaxation method expands the scope of a query by relaxing the constraints implicit in the query. This allows the database to return answers related to the original query as well as the literal answers themselves. These additional answers may be of interest to the user. In section 1 we introduce the problem and method. In Section 2 we give some background on the research done in cooperative answering. Section 3 discusses the relaxation method, a potential control strategy, and uses. Section 4 looks at a semantic counterpart to this notion. In Section 5 we explore some of the control and efficiency issues. We enumerate open issues in Section 6, and conclude in Section 7.  相似文献   

16.
The k-nearest-neighbor (k-NN) query is one of the most popular spatial query types for location-based services (LBS). In this paper, we focus on k-NN queries in time-dependent road networks, where the travel time between two locations may vary significantly at different time of the day. In practice, it is costly for a LBS provider to collect real-time traffic data from vehicles or roadside sensors to compute the best route from a user to a spatial object of interest in terms of the travel time. Thus, we design SMashQ, a server-side spatial mashup framework that enables a database server to efficiently evaluate k-NN queries using the route information and travel time accessed from an external Web mapping service, e.g., Microsoft Bing Maps. Due to the expensive cost and limitations of retrieving such external information, we propose three shared execution optimizations for SMashQ, namely, object grouping, direction sharing, and user grouping, to reduce the number of external Web mapping requests and provide highly accurate query answers. We evaluate SMashQ using Microsoft Bing Maps, a real road network, real data sets, and a synthetic data set. Experimental results show that SMashQ is efficient and capable of producing highly accurate query answers.  相似文献   

17.
Users of electronic medical databases request pertinent information by recasting their clinical questions into a formal database query language. Because the query language is the user's only access to the data, the query language must be powerful enough to enable users to express their data requirements. However, a competing need is for the query language to be restrictive enough so that queries can have unambiguous semantics and the query processor can generate correct answers. We describe a query language, called TQuery , that was designed specifically to formulate database queries that are dependent on temporal and contextual relationships. TQuery specifications express contextual constraints without the need to explicitly reference calendar dates. TQuery is the database query language used to retrieve patient data from an object-oriented electronic patient medical-record system called the temporal network (TNET). TNET and TQuery were developed to support the real-time temporal reasoning and representation needs of a LISP workstation-based medical expert system.  相似文献   

18.
基于用户查询意图识别的Web搜索优化模型   总被引:2,自引:1,他引:1  
杨艺  周元 《计算机科学》2012,39(1):264-267
在对用户查询意图进行分析分类的基础上,提出了一种Web搜索优化模型。该模型通过识别用户查询意图来查询意图特征词和内容主题词的双重约束,再结合用户查询行为获得查询目标,既保证了用户查询意图的准确匹配,又自动过滤和屏蔽了不相关信息。与相关工作对比,其重点在于准确获取用户查询意图,提高用户满意度。实验结果表明,该模型在实现信息搜索准确性和用户对查询结果满意度方面比传统搜索方法有明显改善。  相似文献   

19.
A cooperative interface that, using suitable user models, alters the processing of the user's queries to include additional information that will block faulty inferences is described. In a sense, the interface actively teaches the user facts about the database not explicitly asked for. User interaction with the database then becomes a learning and discovery process guided by the queries posed to the interface. A semantics for user models is introduced that captures, with the help of default logic, the nonmonotonic behavior users normally exhibit. Results showing that the cooperative interface generates enough additional information to block all faulty inferences are presented  相似文献   

20.
Web search users complain of the inaccurate results produced by current search engines. Most of these inaccurate results are due to a failure to understand the user??s search goal. This paper proposes a method to extract users?? intentions and to build an intention map representing these extracted intentions. The proposed method makes intention vectors from clicked pages from previous search logs obtained on a given query. The components of the intention vector are weights of the keywords in a document. It extracts user??s intentions by using clustering the intention vectors and extracting intention keywords from each cluster. The extracted the intentions on a query are represented in an intention map. For the efficiency analysis of intention map, we extracted user??s intentions using 2,600 search log data a current domestic commercial search engine. The experimental results with a search engine using the intention maps show statistically significant improvements in user satisfaction scores.  相似文献   

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