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1.
计算机软件作为现代图书馆发展的重要组成部分,具有手工管理所无法比拟的优点。例如,检索迅速、查找方便、存储量大、可靠性高、寿命长、成本低等。这些优点能够极大地提高图书管理的效率,也是图书管理规范化、信息化、数字化的必然趋势,以及为与国内外图书馆接轨提供了重要条件。本文重点对有关图书馆图书管理系统的相关使用功能需求进行介绍,并在此基础上提出数据库设计方案,并对此方案进行改进,弥补了之前相关数据库设计的不足。 相似文献
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《Information processing & management》2002,38(2):273-291
With the growing focus on what is collectively known as “knowledge management”, a shift continues to take place in commercial information system development: a shift away from the well-understood data retrieval/database model, to the more complex and challenging development of commercial document/information retrieval models. While document retrieval has had a long and rich legacy of research, its impact on commercial applications has been modest. At the enterprise level most large organizations have little understanding of, or commitment to, high quality document access and management. Part of the reason for this is that we still do not have a good framework for understanding the major factors which affect the performance of large-scale corporate document retrieval systems. The thesis of this discussion is that document retrieval—specifically, access to intellectual content—is a complex process which is most strongly influenced by three factors: the size of the document collection; the type of search (exhaustive, existence or sample); and, the determinacy of document representation. Collectively, these factors can be used to provide a useful framework for, or taxonomy of, document retrieval, and highlight some of the fundamental issues facing the design and development of commercial document retrieval systems. This is the first of a series of three articles. Part II (D.C. Blair, The challenge of commercial document retrieval. Part II. A strategy for document searching based on identifiable document partitions, Information Processing and Management, 2001b, this issue) will discuss the implications of this framework for search strategy, and Part III (D.C. Blair, Some thoughts on the reported results of Text REtrieval Conference (TREC), Information Processing and Management, 2002, forthcoming) will consider the importance of the TREC results for our understanding of operating information retrieval systems. 相似文献
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在软件开发和系统的运行过程中,日志管理是一个非常重要的部分。通过对在Log4J的基础上设计出适用于特定系统的日志输出组件进行的研究,从而减少了系统中大量冗余代码,提高了开发效率及开发的一致性。 相似文献
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Automatic text summarization attempts to provide an effective solution to today’s unprecedented growth of textual data. This paper proposes an innovative graph-based text summarization framework for generic single and multi document summarization. The summarizer benefits from two well-established text semantic representation techniques; Semantic Role Labelling (SRL) and Explicit Semantic Analysis (ESA) as well as the constantly evolving collective human knowledge in Wikipedia. The SRL is used to achieve sentence semantic parsing whose word tokens are represented as a vector of weighted Wikipedia concepts using ESA method. The essence of the developed framework is to construct a unique concept graph representation underpinned by semantic role-based multi-node (under sentence level) vertices for summarization. We have empirically evaluated the summarization system using the standard publicly available dataset from Document Understanding Conference 2002 (DUC 2002). Experimental results indicate that the proposed summarizer outperforms all state-of-the-art related comparators in the single document summarization based on the ROUGE-1 and ROUGE-2 measures, while also ranking second in the ROUGE-1 and ROUGE-SU4 scores for the multi-document summarization. On the other hand, the testing also demonstrates the scalability of the system, i.e., varying the evaluation data size is shown to have little impact on the summarizer performance, particularly for the single document summarization task. In a nutshell, the findings demonstrate the power of the role-based and vectorial semantic representation when combined with the crowd-sourced knowledge base in Wikipedia. 相似文献
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利用RDF语义性特点，结合ASP和DOM等中间件技术进行数据预处理，在此基础上提出一种基于RDF技术的Web数据挖掘系统框架，并给出系统框架实现策略，为解决Web数据挖掘所遇到的难题提供有效途径。 相似文献
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信息管理系统的开发通常遵循分层体系结构,而数据层是多层体系中最为关键和重要的一层。数据建模是对数据进行分析和设计的一种有效手段。利用多年系统开发经验对数据层的开发过程进行总结,归纳出了一套有效的数据层开发框架,并对这个框架的实施步骤进行了描述。通过一个实例来说明如何运用这个框架将数据模型映射为关系数据库和代码,从而实现将3者有机地结合起来,快速地完成代码的编写和单元测试工作。最后对这个框架的适用范围和下一步的研究内容进行了探讨。 相似文献
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This paper proposes an approach to tackle the problem of querying large volume of statistical RDF data. Our approach relies on pre-aggregation strategies to better manage the analysis of this kind of data. Specifically, we define a conceptual model to represent original RDF data with aggregates in a multidimensional structure. A set of translations rules for converting a well-known multidimensional RDF modelling vocabulary into the proposed conceptual model is then proposed. We implement the conceptual model in six different data stores: two RDF triple stores (Jena TDB and Virtuoso), one graph-oriented NoSQL database (Neo4j), one column-oriented data store (Cassandra), and two relational databases (MySQL and PostGreSQL). We compare the querying performance, with and without aggregates, in these data stores. Experimental results, on real-world datasets containing 81.92 million triplets, show that pre-aggregation allows for reducing query runtime in all data stores. Neo4j NoSQL and relational databases with aggregates outperform triple stores speeding up to 99% query runtime. 相似文献
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《Information processing & management》2019,56(4):1260-1279
This paper presents a robust and comprehensive graph-based rank aggregation approach, used to combine results of isolated ranker models in retrieval tasks. The method follows an unsupervised scheme, which is independent of how the isolated ranks are formulated. Our approach is able to combine arbitrary models, defined in terms of different ranking criteria, such as those based on textual, image or hybrid content representations.We reformulate the ad-hoc retrieval problem as a document retrieval based on fusion graphs, which we propose as a new unified representation model capable of merging multiple ranks and expressing inter-relationships of retrieval results automatically. By doing so, we claim that the retrieval system can benefit from learning the manifold structure of datasets, thus leading to more effective results. Another contribution is that our graph-based aggregation formulation, unlike existing approaches, allows for encapsulating contextual information encoded from multiple ranks, which can be directly used for ranking, without further computations and post-processing steps over the graphs. Based on the graphs, a novel similarity retrieval score is formulated using an efficient computation of minimum common subgraphs. Finally, another benefit over existing approaches is the absence of hyperparameters.A comprehensive experimental evaluation was conducted considering diverse well-known public datasets, composed of textual, image, and multimodal documents. Performed experiments demonstrate that our method reaches top performance, yielding better effectiveness scores than state-of-the-art baseline methods and promoting large gains over the rankers being fused, thus demonstrating the successful capability of the proposal in representing queries based on a unified graph-based model of rank fusions. 相似文献
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Oracle是目前使用最为广泛的大型数据库管理系统,提高Oracle数据库系统的运行效率,是整个计算机信息系统高效运转的前提和保证。影响Oracle数据库应用系统性能的因素,既有软件方面的因素,也有数据运行的硬件环境、网络环境、数据库管理和维护方面的因素等。通过对其优化可以解决数据库系统运行过程中性能突降等问题,以保证系统运行的优良性能。以数据库性能优化的基本原则为基础,从5个方面总结了Oracle数据库的优化调整。 相似文献
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由于人为因素,订单出错是常有的事。采用计算机订单管理系统,能充分发挥计算机精准的特性及擅长处理大数据量的能力,保证处理过程的正确性。该系统基于B/S架构,使用面向对象C#语言和.net框架开发,并充分利用了.net的OO特性,结合MS SQL SERVER,在开发过程中运用多层结构的设计思想（表现层、业务逻辑层、数据访问层）,是一个高内聚、低耦合的MIS系统,能有效的帮助企业实施企业信息化管理,节约运营成本。 相似文献
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图像检索为数字图书馆的发展提供了技术支持,图书馆应重视数字化发展以提升服务质量。本文提出一种数字图书馆图像资源检索框架,并对系统的实现过程做了详细的分析。同时,在提取图像特征时提出了一种基于非下采样的Contourlet变换图像检索算法（NSCT）,能够在大量图像数据中挖掘有效的特征信息。该算法首先对图像进行多尺度、多方向分解,然后计算低频和高频中不同方向的子带系数的标准差和均值作为图像的纹理特征。实验结果显示,本文提出的图像检索框架具有可行性,能够为用户提供更优质的搜索服务,并且与同类特征提取算法进行比较,该算法具有良好的检索性能和较高的查准率、查全率。 相似文献
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本文介绍了城市总体规划成果数据库建设的数据标准设计和数据转换工作,提出了基于Autodesk Map 3D 2005平台的总体规划管理系统和基于ArcGIS的总体规划成果数据库的软件开发思想。 相似文献
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分析了Struts和Hibernate框架的原理和基于框架开发在线考试系统的过程,阐述了食品药品监管局考试系统的体系结构、模块功能.开发框架将整个系统分为表示层、业务处理层、数据持久层和数据库层,提高了系统的运行效率和可维护性. 相似文献
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《Information processing & management》2020,57(6):102341
Today, due to a vast amount of textual data, automated extractive text summarization is one of the most common and practical techniques for organizing information. Extractive summarization selects the most appropriate sentences from the text and provide a representative summary. The sentences, as individual textual units, usually are too short for major text processing techniques to provide appropriate performance. Hence, it seems vital to bridge the gap between short text units and conventional text processing methods.In this study, we propose a semantic method for implementing an extractive multi-document summarizer system by using a combination of statistical, machine learning based, and graph-based methods. It is a language-independent and unsupervised system. The proposed framework learns the semantic representation of words from a set of given documents via word2vec method. It expands each sentence through an innovative method with the most informative and the least redundant words related to the main topic of sentence. Sentence expansion implicitly performs word sense disambiguation and tunes the conceptual densities towards the central topic of each sentence. Then, it estimates the importance of sentences by using the graph representation of the documents. To identify the most important topics of the documents, we propose an inventive clustering approach. It autonomously determines the number of clusters and their initial centroids, and clusters sentences accordingly. The system selects the best sentences from appropriate clusters for the final summary with respect to information salience, minimum redundancy, and adequate coverage.A set of extensive experiments on DUC2002 and DUC2006 datasets was conducted for investigating the proposed scheme. Experimental results showed that the proposed sentence expansion algorithm and clustering approach could considerably enhance the performance of the summarization system. Also, comparative experiments demonstrated that the proposed framework outperforms most of the state-of-the-art summarizer systems and can impressively assist the task of extractive text summarization. 相似文献
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Information retrieval systems consist of many complicated components. Research and development of such systems is often hampered by the difficulty in evaluating how each particular component would behave across multiple systems. We present a novel integrated information retrieval system—the Query, Cluster, Summarize (QCS) system—which is portable, modular, and permits experimentation with different instantiations of each of the constituent text analysis components. Most importantly, the combination of the three types of methods in the QCS design improves retrievals by providing users more focused information organized by topic.We demonstrate the improved performance by a series of experiments using standard test sets from the Document Understanding Conferences (DUC) as measured by the best known automatic metric for summarization system evaluation, ROUGE. Although the DUC data and evaluations were originally designed to test multidocument summarization, we developed a framework to extend it to the task of evaluation for each of the three components: query, clustering, and summarization. Under this framework, we then demonstrate that the QCS system (end-to-end) achieves performance as good as or better than the best summarization engines.Given a query, QCS retrieves relevant documents, separates the retrieved documents into topic clusters, and creates a single summary for each cluster. In the current implementation, Latent Semantic Indexing is used for retrieval, generalized spherical k-means is used for the document clustering, and a method coupling sentence “trimming” and a hidden Markov model, followed by a pivoted QR decomposition, is used to create a single extract summary for each cluster. The user interface is designed to provide access to detailed information in a compact and useful format.Our system demonstrates the feasibility of assembling an effective IR system from existing software libraries, the usefulness of the modularity of the design, and the value of this particular combination of modules. 相似文献
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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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开展气候变化与空气污染之间的反馈响应研究对于有效控制大气污染与温室气体排放、应对气候变化具有十分重要的意义。本文将区域气候模型和空气质量模型有机结合,提出模型互馈集成框架结构,描述了集成中空间与时间尺度问题。将互馈集成系统总体逻辑结构划分为五个层次,即数据层、模型层、集成层、应用层和结果层。介绍了区域气候模型与空气质量模型之间的数据集成接口和功能集成接口。设计并开发了气候变化与空气污染的互馈集成系统,利用该系统可以有效模拟和预估未来区域气候变化的情况,发现空气污染与区域气候变化之间的关系。 相似文献