Automatic Web-based relational data imputation

Data incompleteness is one of the most important data quality problems in enterprise information systems. Most existing data imputing techniques just deduce approximate values for the incomplete attributes by means of some specific data quality rules or some mathematical methods. Unfortunately, approximation may be far away from the truth. Furthermore, when observed data is inadequate, they will not work well. The World Wide Web (WWW) has become the most important and the most widely used information source. Several current works have proven that using Web data can augment the quality of databases. In this paper, we propose a Web-based relational data imputing framework, which tries to automatically retrieve real values from the WWW for the incomplete attributes. In the paper, we try to take full advantage of relations among different kinds of objects based on the idea that the same kind of things must have the same kind of relations with their relatives in a specific world. Our proposed techniques consist of two automatic query formulation algorithms and one graph-based candidates extraction model. Several evaluations are proposed on two high-quality real datasets and one poor-quality real dataset to prove the effectiveness of our approaches.     

WWW与数据库集成系统的用户权限管理

在WWW上的应用,越来越多的体现为多人合作应用形式,这些应用系统大多都需要通过WWW与数据库的集成来实现。但是由于WWW与数据库系统都有自己的用户权限管理,因此集成后在用户管理、权限设定及系统完整性方面就产生了一些问题。文章针对WWW与数据库集成系统,提出用户权限管理结构和机制,并设计了实际系统模型,它将服务器对用户的认证,转变成基于用户角色的对数据库的访问控制,不但能保护WWW与数据库的数据,而且能确保系统结合的完整性,同时更可以大量简化用户管理与权限管制的工作,提高权限管理的效率。     

Discovering and Using Design Patterns in the WWW

In this paper, we discuss how the idea of design patterns can be used in the context of the World Wide Web, for both designing and implementing web sites or more complex information systems. We first motivate our work by discussing which are the most outstanding problems in designing Web-based information systems. Then we briefly introduce design patterns and show how they are used to record and reuse design information. We next present some simple though powerful design patterns and show known uses in the WWW. Finally, we outline a process for building applications by combining a design methodology (OOHDM) with design patterns.     

Query processing with quality control in the World Wide Web

Recent research on integrating database and World Wide Web (WWW) technologies has changed the navigation approach to searching information in the Web. People now can issue queries via a simple query interface or a databaselike query language to retrieve information from semistructured WWW data sources. However, the quality of query processing in the WWW is still low due to many factors such as unpredictable response time, irrelevant results, and outofdate data. Such lowquality query processing is intolerable to either users or service providers. In this paper, we present a qualitycontrolled query processing method in the WWW. Quality parameters that users can specify with their queries are introduced. Distance functions that are used to evaluate the goodness of query quality parameters are defined. A query processing model with quality control is introduced. A quality control protocol in query processing is presented. Qualitycontrolled query scheduling algorithms including admission scheduling, promotion/demotion scheduling and execution scheduling are proposed. Other relevant issues such as query classification, system parameter estimation, and query queue management are also discussed. Query processing with quality control is a promising way to solve the uncertain and lowquality query processing problems in the WWW.     

开放安全的Internet/Intranet信息系统体系结构的研究与实现

由于ＷＷＷ技术的迅猛发展与普及,特别是其开放的体系结构,使得它成为当今计算机应用的理想平台。如今,许多应用,尤其是商业领域的应用,已经在ＷＷＷ上成功地建立起来。但是传统的客户／服务器数据库管理系统与ＷＷＷ互连还存在许多问题,特别是在一些全新的商业应用提出后,这种问题愈显突出。正是在这种背景下,笔者研究了目前 Ｃｌｉｅｎｔ／Ｓｅｒｖｅｒ ＤＢＭＳ与 ＷＷＷ互连中存在的困难和障碍,分析了问题的实质,并提出全新的开放安全 Ｉｎ－ｔｅｒｎｅｔ／Ｉｎｔｒａｎｅｔ信息系统体系结构,对该体系结构的各组成部分进行了详细的定义和研究。在理论研究的基础上,及Ｉｎｔｒａｎｅｔ环境中,设计并实现了一个简单的数据库信息实时发布系统,验证了所取得的部分理论成果,同时以该系统作为基础,还可进一步开发成为实用的商业软件系统。     

Using VRML-based visualisations to facilitate information retrieval in the world wide web

With the explosive growth of information in the WWW, it is becoming increasingly difficult for the user to find information of interest. Visualisations may be helpful in assisting the users in their information retrieval task. Effective visualisation of the structure of a WWW site is extremely useful for browsing through the site. Visualisation can also be used to augment a WWW search engine when too many or too few results are retrieved. In this paper, we discuss several visualisations we have developed to facilitate information retrieval on the WWW. With VRML becoming the standard for graphics on the Web and efficient VRML browsers becoming available, VRML was used for developing these visualisations. Unique visualisations like focus + context views of WWW nodes and semantic visualisation are presented and examples are given on scenarios where the visualisations are useful.     

基于WWW的网络信息共享系统

随着网络信息服务的发展,如何利用人（成千上万的网络用户）─一网络上最宝贵的资源来提高网络信息服务的质量,已经引起了众多学者的注意。文章提出的基于ＷＷＷ的网络信息共享系统,利用社会过滤技术为用户提供良好的信息交流途径,并以用户搜集整理的信息资源为基础建立开放目录服务,是对ＷＷＷ环境中用户合作及参与网络信息管理的有益尝试。     

Internet上信息服务系统的建造、维护和管理

ＷＷＷ（Ｗｏｒｌｄ－ＷｉｄｅＷｅｂ）是Ｉｎｔｅｒｎｅｔ上广泛流行的分布式超媒体信息系统。目前,随着Ｉｎｔｅｒｎｅｔ热潮席卷全球,越来越多的部门、企业甚至个人基于Ｉｎｔｅｒｎｅｔ上的ＷＷＷ设施建造自己的信息系统。但是由于ＷＷＷ系统的固有特点,使得利用现有方法开发的信息系统存在许多问题。该文针对这些问题,提出了建造基于Ｉｎｔｅｒｎｅｔ的分布式超媒体信息系统的一些设想,并给出了实现这一设想的系统模型。     

A decision support system for evaluating intangible investments

In this research project we have connected the procedural and substantive decision support by means of modern information technology. We have showed how the semistructured strategic decisions concerning intangible investments can be supported effectively by relating appropriate analysis methods to the different phases of the investment process. Because for the intangible investments there is no well-defined solution procedure available, a variety of methods must be integrated to support the solution process.

As a demonstrative example we showed how the intangible investments in logistic systems can be managed. It was highlighted that the logistics systems are complex, cross-functional systems that affect all major functions or departments within the firm beginning from the raw material deliveries and ending with the deliveries of finished goods. Investments in the logistics systems have corporatewide, cross-functional effects, and the investment decisions are strategic decisions. Consequently, the investments in the logistics systems should be strategically justified, not only cost-justified. The cross-functional effects imply that the investment analysis concerning the whole logistics system must be fulfilled under multiple, diversified criteria. We can not, however, ignore the financial, cost and revenue oriented, traditional investment criteria. They just have to be used in a new, flexible way in relation to the goals and objectives of the firm.

Strategic planning is a managerial area where semistructured problems frequently exist. One of the key problems faced in strategic management is the issue of investment decisions. Investments in information systems, logistic systems, flexible production systems, corporate image, etc, are examples of complex investment problems that are difficult to quantify and analyze with traditional techniques. Modern computer technology can enrich the analysis and improve the quality of strategic decision making.     

一种基于奇异值分解的双语信息过滤算法

本文提出了一种基于SVD(奇异值分解)的双语信息过滤算法,将双语文档进行了统一的表示,使得适应于单语过滤的算法可以方便地用于双语过滤,同时对文档向量进行了压缩,滤去了噪声。在应用方面,将双语过滤算法用于互联网上的个性化主动信息过滤。