Modeling views in the layered view model for XML using UML

In data engineering, view formalisms are used to provide flexibility to users and user applications by allowing them to extract and elaborate data from the stored data sources. Conversely, since the introduction of Extensible Markup Language (XML), it is fast emerging as the dominant standard for storing, describing, and interchanging data among various web and heterogeneous data sources. In combination with XML Schema, XML provides rich facilities for defining and constraining user-defined data semantics and properties, a feature that is unique to XML. In this context, it is interesting to investigate traditional database features, such as view models and view design techniques for XML. However, traditional view formalisms are strongly coupled to the data language and its syntax, thus it proves to be a difficult task to support views in the case of semi-structured data models. Therefore, in this paper we propose a Layered View Model (LVM) for XML with conceptual and schemata extensions. Here our work is three-fold; first we propose an approach to separate the implementation and conceptual aspects of the views that provides a clear separation of concerns, thus, allowing analysis and design of views to be separated from their implementation. Secondly, we define representations to express and construct these views at the conceptual level. Thirdly, we define a view transformation methodology for XML views in the LVM, which carries out automated transformation to a view schema and a view query expression in an appropriate query language. Also, to validate and apply the LVM concepts, methods and transformations developed, we propose a view-driven application development framework with the flexibility to develop web and database applications for XML, at varying levels of abstraction

The role of human factors in stereotyping behavior and perception of digital library users: A robust clustering approach

To deliver effective personalization for digital library users, it is necessary to identify which human factors are most relevant in determining the behavior and perception of these users. This paper examines three key human factors: cognitive styles, levels of expertise and gender differences, and utilizes three individual clustering techniques: k-means, hierarchical clustering and fuzzy clustering to understand user behavior and perception. Moreover, robust clustering, capable of correcting the bias of individual clustering techniques, is used to obtain a deeper understanding. The robust clustering approach produced results that highlighted the relevance of cognitive style for user behavior, i.e., cognitive style dominates and justifies each of the robust clusters created. We also found that perception was mainly determined by the level of expertise of a user. We conclude that robust clustering is an effective technique to analyze user behavior and perception

Automatic Profile Generation for Visual-Impaired Users

Currently, there are a growing number of tools that allow web developers to evaluate the accessibility of their web pages and sites. Many tools also prompt the developer to make specific repairs; and some tools automatically follow links to evaluate multiple pages within a site or within an entire domain. Although tools such as these can be very useful to identify accessibility problems, many accessibility issues are subjective and cannot be assessed without manual inspection. We believe that accessibility assessment and repair should be addressed as related activities intelligently supported. To do so, a main aspect to be considered is the automatic identification of user disabilities. In this paper we introduce an agent-based solution to tackle this problem. The agent is conceived to provide knowledge for the creation and classification of visually-impaired users profiles in terms of stereotypes. We apply and test the performance of our agent by profiling surveyed users. Our solution will be part of a multi-agent system to drive intelligently the accessibility conformance process.Sociedad Argentina de Informática e Investigación Operativa (SADIO

Will this work for Susan? Challenges for delivering usable and useful generic linked data browsers

While we witness an explosion of exploration tools for simple datasets on Web 2.0 designed for use by ordinary citizens, the goal of a usable interface for supporting navigation and sense-making over arbitrary linked data has remained elusive. The purpose of this paper is to analyse why - what makes exploring linked data so hard? Through a user-centered use case scenario, we work through requirements for sense making with data to extract functional requirements and to compare these against our tools to see what challenges emerge to deliver a useful, usable knowledge building experience with linked data. We present presentation layer and heterogeneous data integration challenges and offer practical considerations for moving forward to effective linked data sensemaking tools

Automated end user-centred adaptation of web components through automated description logic-based reasoning

Context: This paper addresses one of the major end-user development (EUD) challenges, namely, how to pack today?s EUD support tools with composable elements. This would give end users better access to more components which they can use to build a solution tailored to their own needs. The success of later end-user software engineering (EUSE) activities largely depends on how many components each tool has and how adaptable components are to multiple problem domains. Objective: A system for automatically adapting heterogeneous components to a common development environment would offer a sizeable saving of time and resources within the EUD support tool construction process. This paper presents an automated adaptation system for transforming EUD components to a standard format. Method: This system is based on the use of description logic. Based on a generic UML2 data model, this description logic is able to check whether an end-user component can be transformed to this modeling language through subsumption or as an instance of the UML2 model. Besides it automatically finds a consistent, non-ambiguous and finite set of XSLT mappings to automatically prepare data in order to leverage the component as part of a tool that conforms to the target UML2 component model. Results: The proposed system has been successfully applied to components from four prominent EUD tools. These components were automatically converted to a standard format. In order to validate the proposed system, rich internet applications (RIA) used as an operational support system for operators at a large services company were developed using automatically adapted standard format components. These RIAs would be impossible to develop using each EUD tool separately. Conclusion: The positive results of applying our system for automatically adapting components from current tool catalogues are indicative of the system?s effectiveness. Use of this system could foster the growth of web EUD component catalogues, leveraging a vast ecosystem of user-centred SaaS to further current EUSE trends

Automatic Profile Generation for Visual-Impaired Users

Currently, there are a growing number of tools that allow web developers to evaluate the accessibility of their web pages and sites. Many tools also prompt the developer to make specific repairs; and some tools automatically follow links to evaluate multiple pages within a site or within an entire domain. Although tools such as these can be very useful to identify accessibility problems, many accessibility issues are subjective and cannot be assessed without manual inspection. We believe that accessibility assessment and repair should be addressed as related activities intelligently supported. To do so, a main aspect to be considered is the automatic identification of user disabilities. In this paper we introduce an agent-based solution to tackle this problem. The agent is conceived to provide knowledge for the creation and classification of visually-impaired users profiles in terms of stereotypes. We apply and test the performance of our agent by profiling surveyed users. Our solution will be part of a multi-agent system to drive intelligently the accessibility conformance process.Sociedad Argentina de Informática e Investigación Operativa (SADIO

The Present and Future of Internet Search

Search engines were crucial in the development of the World Wide Web. Web-based information retrieval progressed from simple word matching to sophisticated algorithms for maximizing the relevance of search results. Statistical and graph-based approaches for indexing and ranking pages, natural language processing techniques for improving query results, and intelligent agents for personalizing the search process all show great promise for enhanced performance. The evolution in search technology was accompanied by growing economic pressures on search engine companies. Unable to sustain long-term viability from advertising revenues, many of the original search engines diversified into portals that farm out their search and directory operations. Vertical portals that serve focused user communities also outsource their search services, and even directory providers began to integrate search engine technologies from outside vendors. This article brings order to the chaos resulting from the variety of search tools being offered under various marketing guises. While growing reliance on a small set of search providers is leading to less diversity among search services, users can expect individualized searching experiences that factor in personal information. The convergence of technology and business models also results in more narrowly defined search spaces, which will lessen the quantity of search results while improving their quality

Peer-to-Peer Grids

We describe Peer-to-Peer Grids built around Integration of technologies from the peer-to-peer and Grid fields. We focus on the role of Web services linked by a powerful event service using uniform XML interfaces and application level routing. We describe how a rich synchronous and asynchronous collaboration environment can support virtual communities built on top of such infrastructure. Universal access mechanisms are discussed