基于Micap资料的地市级SQL Server数据库处理系统

本文介绍了以Micaps资料为依托,建立地市一级气象台远程SQL Server数据库的过程,并从预报的角度对这些数据库资料进行了一些简单的应用。结果表明:SQL数据库建成后,常规资料可以在江西省内气象台站共享,各台站无需每天保存刻盘,查询某一段时间、某一类强天气的平均场变得非常简单,如月平均场、区域暴雨平均场等,这些都为地市一级气象台的预报准备了资料和方法。同时运用SQL查询数据资料可以很方便地建立一些预报指标,并对以前老预报员在预报实践中得出的预报指标进行检验,并且SQL查询的结果就是一回归序列,可以直接用来建立回归方程,形成各类天气的预报方法。     

基于Hibernate的数据持久化应用研究

Hibernate是一个对象持久化工具,它通过其强大的O/R映射功能将Java对象同存放于关系数据库中的数据进行映射,避免了开发人员使用大量的SQL语句通过JDBC的方式对数据库进行操作,可以有效地提高开发的效率。将其应用于企业在线资产管理系统,可充分利用其优点。     

基于SP防范SQL注入攻击的三层信息系统安全设计研究

SQL注入攻击是一种利用客户端输入构建特殊SQL查询语句进行数据库攻击的攻击方式。开发一种三层架构的信息系统,可检测和过滤用户的非法输入,在数据层使用SP（Store Produce）存储过程进行数据存取,以更有效地防范SQL注入攻击,提升系统安全性能。     

轻松学SQL实现简单查询

随着计算机技术越来越普及.广泛地应用于各个领域,数据库技术与应用的结合越来越紧密.数据库管理系统作为一个高级的系统软件,涉及到查询处理、并发控制、故障恢复等重要技术.本文对倚单的SOL查询.给出几个方法.使初学者轻松学会使用SOL实现查询.     

基于SQL智能解析的代码生成引擎

通过智能SQL解析动态构造的SQL,并为SQL设置参数随机值,然后在数据库执行这条SQL,可以得到SQL的输入参数及参数类型,还有查询返回列。根据这些数据生成代码,可以为SQL驱动的信息管理等企业应用开发加速,提升开发效率。     

基于ADO.NET的XML与SQL Server 2000数据交换研究与应用

介绍了XML的概念和一些特点，分析了XML和SQL Server2000数据交换的几种方式，以及在SQL Server2000中，使用SELECT语句可以把查询结果存储为XML文档，使用OPENXML语句提供了在关系数据库表中存储XML文档的功能，并实际实现了SQL Server2000和XML之间的数据交换。     

Multitasking during Web search sessions

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.     

A relational vector space model using an advanced weighting scheme for image retrieval

In this paper, we lay out a relational approach for indexing and retrieving photographs from a collection. The increase of digital image acquisition devices, combined with the growth of the World Wide Web, requires the development of information retrieval (IR) models and systems that provide fast access to images searched by users in databases. The aim of our work is to develop an IR model suited to images, integrating rich semantics for representing this visual data and user queries, which can also be applied to large corpora.     

关系数据库查询优化策略研究

作为数据的承载平台,数据库在各行各业都得到了广泛应用。查询操作是数据库管理系统最重要的功能之一,使用频率最高。以关系型数据库为基础,从不同的角度出发,对数据库查询优化策略进行了研究。     

Querying XML documents using Prolog engines: When is this a good idea?

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.     

An analysis of Web searching by European AlltheWeb.com users

The Web has become a worldwide source of information and a mainstream business tool. It is changing the way people conduct the daily business of their lives. As these changes are occurring, we need to understand what Web searching trends are emerging within the various global regions. What are the regional differences and trends in Web searching, if any? What is the effectiveness of Web search engines as providers of information? As part of a body of research studying these questions, we have analyzed two data sets collected from queries by mainly European users submitted to AlltheWeb.com on 6 February 2001 and 28 May 2002. AlltheWeb.com is a major and highly rated European search engine. Each data set contains approximately a million queries submitted by over 200,000 users and spans a 24-h period. This longitudinal benchmark study shows that European Web searching is evolving in certain directions. There was some decline in query length, with extremely simple queries. European search topics are broadening, with a notable percentage decline in sexual and pornographic searching. The majority of Web searchers view fewer than five Web documents, spending only seconds on a Web document. Approximately 50% of the Web documents viewed by these European users were topically relevant. We discuss the implications for Web information systems and information content providers.     

校园GIS查询系统的实现

在分析了现有校园地理信息系统查询功能不足的基础上，本文阐述了建立校NGIS查询系统的必要性，对校园GIS查询系统进行了系统化的改进.并讨论了在VisualBasic环境下集成Mapinfo的方法，对Mapinfo进行二次开发，编程实现了信息工具查询、位置查找、SQL查询和范围查询的功能。     

一种面向Web搜索的查询修正方案

本文分析了正方法,查询修正中的用户信息行为,吸收网页抓取、检索与浏览并重的思想,综合考虑用户Web搜索过程中的行为特点、查询修正所用词汇的可用来源,给出一个新的面向Web搜索的查询修正解决方案.     

CIDER: Concept-based image diversification,exploration, and retrieval

Many of the approaches to image retrieval on the Web have their basis in text retrieval. However, when searchers are asked to describe their image needs, the resulting query is often short and potentially ambiguous. The solution we propose is to perform automatic query expansion using Wikipedia as the source knowledge base, resulting in a diversification of the search results. The outcome is a broad range of images that represent the various possible interpretations of the query. In order to assist the searcher in finding images that match their specific intentions for the query, we have developed an image organization method that uses both the conceptual information associated with each image, and the visual features extracted from the images. This, coupled with a hierarchical organization of the concepts, provides an interactive interface that takes advantage of the searchers’ abilities to recognize relevant concepts, filter and focus the search results based on these concepts, and visually identify relevant images while navigating within the image space. In this paper, we outline the key features of our image retrieval system (CIDER), and present the results of a preliminary user evaluation. The results of this study illustrate the potential benefits that CIDER can provide for searchers conducting image retrieval tasks.     

基于数据库分类的deep web爬行器研究

在现有相关研究的基础上,设计一种基于数据库分类的deep web爬行器。该爬行器首先从抓取的网页中识别出deep web数据库的入口表单,然后采用查询探测方法对数据库进行自动分类,并根据分类结果来选取一组合适的关键词作为查询词,自动填写入口表单中的文本框并向数据库提出查询请求。实验结果表明,基于数据库分类的deep web爬行器的爬行效果要优于基于指定查询词的deep web爬行器的爬行效果。     

C~#实现公安通信信息查询系统

为了提高公安系统对通话业务相关信息查询的准确性、快速性,减轻技术人员劳动强度,强化查询信息的安全性,简化查询流程,在总结分析目前信息查询现状后,运用C#语言、结合Oracle数据库技术,开发了公安通信信息查询系统,实现了自动查询、保存、发送查询信息。     

Efficient querying of multidimensional RDF data with aggregates: Comparing NoSQL,RDF and relational data stores

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.     

Object identification and retrieval from efficient image matching. Snap2Tell with the STOIC dataset

Traditional content based image retrieval attempts to retrieve images using syntactic features for a query image. Annotated image banks and Google allow the use of text to retrieve images. In this paper, we studied the task of using the content of an image to retrieve information in general. We describe the significance of object identification in an information retrieval paradigm that uses image set as intermediate means in indexing and matching. We also describe a unique Singapore Tourist Object Identification Collection with associated queries and relevance judgments for evaluating the new task and the need for efficient image matching using simple image features. We present comprehensive experimental evaluation on the effects of feature dimensions, context, spatial weightings, coverage of image indexes, and query devices on task performance. Lastly we describe the current system developed to support mobile image-based tourist information retrieval.     

Automatic query formulations in information retrieval.

Modern information retrieval systems are designed to supply relevant information in response to requests received from the user population. In most retrieval environments the search requests consist of keywords, or index terms, interrelated by appropriate Boolean operators. Since it is difficult for untrained users to generate effective Boolean search requests, trained search intermediaries are normally used to translate original statements of user need into useful Boolean search formulations. Methods are introduced in this study which reduce the role of the search intermediaries by making it possible to generate Boolean search formulations completely automatically from natural language statements provided by the system patrons. Frequency considerations are used automatically to generate appropriate term combinations as well as Boolean connectives relating the terms. Methods are covered to produce automatic query formulations both in a standard Boolean logic system, as well as in an extended Boolean system in which the strict interpretation of the connectives is relaxed. Experimental results are supplied to evaluate the effectiveness of the automatic query formulation process, and methods are described for applying the automatic query formulation process in practice.