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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 viewdriven application development framework with the flexibility to develop web and database applications for XML, at varying levels of abstraction.

Today, eXtensible Markup Language (XML) is fast emerging as the dominant standard for storing, describing, representing and interchanging data among various enterprises systems and databases in the context of complex web enterprises information systems (EIS). Conversely, for web EIS (such as ecommerce and portals) to be successful, it is important to apply a high level, model driven solutions and meta‐data vocabularies to design and implementation techniques that are capable of handling heterogonous schemas and documents. For this, we need a methodology that provides a higher level of abstraction of the domain in question with rigorously defined standards that are to be more widely understood by all stakeholders of the system. To‐date, UML has proven itself as the language of choice for modeling EIS using OO techniques. With the introduction of XML Schema, which provides rich facilities for constraining and defining enterprise XML content, the combination of UML and XML technologies provide a good platform (and the flexibility) for modeling, designing and representing complex enterprise contents for building successful EIS. In this paper, we show how a layered view model coupled with a proven user interface analysis framework (WUiAM) is utilized in providing architectural construct and abstract website model (called eXtensible Web, xWeb), to model, design and implement simple, usercentred, collaborative websites at varying levels of abstraction. The uniqueness xWeb is that the model data (web user interface definitions, website data descriptions and constraints) and the web content are captured and represented at the conceptual level using views (one model) and can be deployed (multiple platform specific models) using one or more implementation models.

The purpose of this paper is to consider the secure publishing of XML documents, where a single copy of an XML document is disseminated and a stated role‐based access control policy (RBACP) is enforced via selective encryption. It describes a more efficient solution over previously proposed approaches, in which both policy specification and key generation are performed once, at the schema‐level. In lieu of the commonly used super‐encryption technique, in which nodes residing in the intersection of multiple roles are encrypted with multiple keys, it describes a new approach called multi‐encryption that guarantees each node is encrypted at most once.

This paper describes two alternative algorithms for key generation and single‐pass algorithms for multi‐encrypting and decrypting a document. The solution typically results in a smaller number of keys being distributed to each user.

The paper proves the correctness of the presented algorithms, and provides experimental results indicating the superiority of multi‐encryption over super‐encryption, in terms of encryption and decryption time requirements. It also demonstrates the scalability of the approach as the size of the input document and complexity of the schema‐level RBACP are increased.

An extension of this work involves designing and implementing re‐usability of keyrings when a schema or ACP is modified. In addition, more flexible solutions for handling cycles in schema graphs are possible. The current solution encounters difficulty when schema graphs are particularly deep and broad.

The experimental results indicate that the proposed approach is scalable, and is applicable to scenarios in which XML documents conforming to a common schema are to be securely published.

This paper contributes to the efficient implementation of secure XML publication systems.

XML Schema Definition (XSD) is in the logical level of XML model and is used in most web applications. At present, there is no standard format for the conceptual level of XML model. Therefore, we introduce an XML Tree Model as an XML conceptual schema for representing and confirming the data semantics according to the user requirements in a diagram. The XML Tree Model consists of nodes representing all elements within the XSD. We apply reverse engineering from an XSD to an XML Tree Model to assist end users in applying an XML database for information highway on the Internet. The data semantics recovered for visualization include root element, weak elements, participation, cardinality, aggregation, generalization, categorization, and n‐ary association, and which can be derived by analyzing the structural constraints of XSD based on its key features such as key, keyref, minOccurs, maxOccurs, Choice, Sequence and extension. We use the Eclipse user interface for generating a graphical view for XML conceptual schema.

While the World Wide Web (WWW or Web) is steadily expanding, electronic books (e‐books) remain a niche market. In this article, it is first postulated that specialized contents and device independence can make Web‐based e‐books compete with paper prints; and that adaptive features that can be implemented by client‐side computing are relevant for e‐books, while more complex forms of adaptation requiring server‐side computations are not. Then, enhancements of the WWW standards (specifically of XML, XHTML, of the style‐sheet languages CSS and XSL, and of the linking language XLink) are proposed for a better support of client‐side adaptation and device independent content modeling. Finally, advanced browsing functionalities desirable for e‐books as well as their implementation in the WWW context are described.

The use of XML in the lifecycle of e‐journals has recently emerged as a hot topic in the library world. This burst of interest is largely due to proposals to use XML in e‐journal archiving and also a growing awareness of the advantages of XML for metadata. But the publishing community are increasingly viewing XML as playing a central role in the future of the entire e‐journals process. The papers in this special issue cover a breadth of opinion but there is a common theme; namely, that XML and its related technologies can help to fulfil the promise of e‐journals.

Extensible Markup Language (XML)‐based data integration systems (DIS) aim to support global updates. Data consistency among data sources is not yet enforced at the integration level or enforced in an ad hoc manner which leads to redundant checking of consistency or unrepairable mistakes. This paper aims to provide XQuery trigger service to enforce data integrity and data consistency in the DIS at the integration level.

Data consistency is enforced among data sources through providing XQuery trigger service for the XML‐DIS. An XQuery trigger model is defined and shown how to use this model to define different integrity constraints and triggers at the integration level. The paper proposes the architecture of the XQuery trigger service and shows how to enforce data consistency in the DIS. Important components including event detection, condition evaluation and action firing are discussed. Necessary algorithms including how to produce ChangeRecord, how to find activated triggers, how to process LET and FOR clauses and how to create data objects from XML fragment are proposed. Trigger termination and failure handling are also discussed.

XQuery trigger can express miscellaneous data integrity constraints and triggers in the DIS and is highly abstract, refined and easy to understand. XQuery trigger service provides an easy‐to‐maintain method of the data consistency rules and a uniform, nonredundant and centralized enforcement of data consistency.

An XQuery trigger model with namespace annotations, which can define constraints and triggers among different data sources. An XQuery trigger service architecture for the XML‐DIS, which can enforce data consistency at the integration level. For DIS administrators, who want to enforce data consistency when permitting updates at the integration level.

XML emerges and evolves quick and fast as Web and wireless technology penetrates more into the consumer marketplace. Database technology faces new challenges. It has to change to play the supportive role. Web and wireless applications master the technology paradigm shift. XML and database connectivity and transformation become critical. Heterogeneity and interoperability must be distinctly tackled. In this paper, we provide an in‐depth and technical review of XML and XML database technology. An analytic and comparative framework is developed. Storage method, mapping technique, and transformation paradigm formulate the framework. We collect and compile the IBM, Oracle, Sybase, and Microsoft XML database products. We use the framework and analyze each of these XML database techniques. The comparison and contrast aims to provide an insight into the structural and methodological paradigm shift in XML database technology.

Reports the benefits of using extensible markup language (XML) to support knowledge management of financial information. Current search engines cannot provide sufficient performance to support users of financial information, which includes both non‐structured items and well‐structured items. For investors, making a high‐quality decision sometimes requires both. XML can help by providing tags to create structure. XML provides a vendor‐neutral approach. XML authors can create arbitrary tags to describe the format or structure of data, and are not restricted to the tags in the specification for HTML. A prototype XML‐based Electronic Financial Filing System (ELFFS‐XML) has been developed to illustrate how to apply XML to model and add value to traditional HTML‐based financial information by cross‐linking related information from different data sources. Compares the functionality of XML‐based ELFFS with the original HTML‐based ELFFS and SEDAR, an electronic filing system used in Canada, and recommends some directions for future development of similar electronic filing systems.

To provide a more requirements‐driven workload model for eXtensible Markup Language (XML) benchmark over the electronic data exchange and management in collaborative commerce.

A three‐component workload requirements model is formulated. They are the XML object model, the XML query operation model, and the control model. The object model extended from W3C data model gives a set of more generic data and document model. The query model enhanced from current and common benchmarks gives a more generalized set of standard and open queries against XML data and documents. The control model compiled from TPC and industry standards gives a set of more systematic experimental variables and performance metrics to set up and conduct an XML benchmark.

The long‐standing research issues of domain dependency and application irreproducibility of XML benchmarks are addressed, tackled and offered with a novel and computer‐aided alternative. Precision and cost‐effectiveness through a synthetic, standard, and scalable set of requirements‐driven workload model are presented.

XML constructs, constraints, and controls are investigated both in terms of data and documents. Workload formulation from the requirements analysis is explored. In‐depth schema, query, and control model to provide scalability and portability can be applied is developed.

Enterprise information integration over heterogeneous data sources has to be achieved through XML. Performance measurement and evaluation on XML is vital. With a more generic and generalized design, XML benchmark can become the key to the success of B2Bi interoperability and performance.

An origin of requirements‐driven benchmark modeling over collaborative commerce is presented. A novel extension on W3C XML model is created. A innovative enhancement from current XML benchmarks' query model is developed.