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The World Wide Web has undergone a rapid transition from the originally static hypertext to an ubiquitous hypermedia system. Today, the Web is not only used as a basis for distributed applications (Web applications), moreover it serves as a generic architecture for autonomous applications and services. Many research work has been done regarding the modeling and engineering process of Web applications and various platforms, frameworks and development kits exist for the efficient implementation of such systems. Concerning the modeling process, many of the published concepts try to merge traditional hypermedia modeling with techniques from the software engineering domain. Unfortunately, those concepts which capture all facets of the Web’s architecture become rather bulky and are eventually not applicable for a model‐driven Web application development. Moreover, there is a need for frameworks which address both, the modeling process and the implementation task and allow a model driven, semi‐automatic engineering process using CASE tools. This paper outlines the DaVinci Web Engineering Framework which supports the modeling as well as the semi‐automated implementation of Web applications. The DaVinci Architectural Layer specifies a persistent, hierarchical GUI model and a generic interaction scheme. This allows the elimination of the hypermedia paradigm, which turned out to be rather practical when building Web applications.

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.

Ubiquitous web applications (UWA) are a new type of web applications which are accessed in various contexts, i.e. through different devices, by users with various interests, at anytime from anyplace around the globe. For such full‐fledged, complex software systems, a methodologically sound engineering approach in terms of model‐driven engineering (MDE) is crucial. Several modeling approaches have already been proposed that capture the ubiquitous nature of web applications, each of them having different origins, pursuing different goals and providing a pantheon of concepts. This paper aims to give an in‐depth comparison of seven modeling approaches supporting the development of UWAs.

This methodology is conducted by applying a detailed set of evaluation criteria and by demonstrating its applicability on basis of an exemplary tourism web application. In particular, five commonly found ubiquitous scenarios are investigated, thus providing initial insight into the modeling concepts of each approach as well as to facilitate their comparability.

The results gained indicate that many modeling approaches lack a proper MDE foundation in terms of meta‐models and tool support. The proposed modeling mechanisms for ubiquity are often limited, since they neither cover all relevant context factors in an explicit, self‐contained, and extensible way, nor allow for a wide spectrum of extensible adaptation operations. The provided modeling concepts frequently do not allow dealing with all different parts of a web application in terms of its content, hypertext, and presentation levels as well as their structural and behavioral features. Finally, current modeling approaches do not reflect the crosscutting nature of ubiquity but rather intermingle context and adaptation issues with the core parts of a web application, thus hampering maintainability and extensibility.

Different from other surveys in the area of modeling web applications, this paper specifically considers modeling concepts for their ubiquitous nature, together with an investigation of available support for MDD in a comprehensive way, using a well‐defined as well as fine‐grained catalogue of more than 30 evaluation criteria.

The main purpose of this paper is to improve a web content management system (WCMS) product line for future implementations by identifying software commonalities in WCMS‐based web applications. WCMS plays a central role in modern web application development: most large public and internal web sites are based on a WCMS foundation. If we can improve the implementation process, the effectiveness and efficiency of web application development will increase significantly.

This research identifies reusable solutions from existing WCMS implementations using problem diagrams and structured goal modeling. From configurations were matched with atomic e‐business models by linking them to the strategic competencies through bottom‐up goal modeling. A designed method was constructed on how requirements can be elicited for WCMS implementations using goal modeling and problem frames.

The resulting method provides insight in relevant e‐business models and their relation to software product lines. Moreover, the approach is applied in a WCMS study which demonstrates its applicability.

The practical implications of this research is twofold: WCMS developers now have a method to improve their product line based on e‐business models; and requirements engineers implementing WCMS can use this model to apply reusable software and prioritize requirements. Both will potentially have a large impact on the effectiveness of implementations since most web applications are developed with WCMS.

The paper presents a novel approach for efficient and effective identification of software commonalities. This research is part of the web engineering method that focuses on development of web applications based on WCMSs.

The purpose of this study is twofold: to investigate whether it is meaningful to use the Engineering Index (Ei) classification scheme for browsing, and then, if proven useful, to investigate the performance of an automated classification algorithm based on the Ei classification scheme.

A user study was conducted in which users solved four controlled searching tasks. The users browsed the Ei classification scheme in order to examine the suitability of the classification systems for browsing. The classification algorithm was evaluated by the users who judged the correctness of the automatically assigned classes.

The study showed that the Ei classification scheme is suited for browsing. Automatically assigned classes were on average partly correct, with some classes working better than others. Success of browsing showed to be correlated and dependent on classification correctness.

Further research should address problems of disparate evaluations of one and the same web page. Additional reasons behind browsing failures in the Ei classification scheme also need further investigation.

Improvements for browsing were identified: describing class captions and/or listing their subclasses from start; allowing for searching for words from class captions with synonym search (easily provided for Ei since the classes are mapped to thesauri terms); when searching for class captions, returning the hierarchical tree expanded around the class in which caption the search term is found. The need for improvements of classification schemes was also indicated.

A user‐based evaluation of automated subject classification in the context of browsing has not been conducted before; hence the study also presents new findings concerning methodology.

In response to the increasing number of open‐source software (OSS) project initiatives and the increasing demand of OSS products as alternative solutions by industries, it is important for particular stakeholders such as the project host/supporter project‐leading teams, and prospective customers to determine whether a project initiative is likely to be sustainable and is worth supporting. This paper aims to propose a concept of “health” indicators and an evaluation process that can help to get a status overview of OSS projects in a timely fashion and predict project survivability based on the project data available on web repositories.

For initial empirical evaluation of the concept, the indicators are applied to well‐known web‐based OSS projects (Apache Tomcat and Apache HTTP Server) and the results are compared with challenged projects (Apache Xindice and Apache Slide). The results are discussed with OSS experts to investigate the external validity of the indicators.

From a software project management point of view, a typical web‐based OSS project can be viewed as a web‐engineering process, since most OSS projects exploit the benefits of a web platform and enable the project community to collaborate using web‐based project tools and repositories such as mailing lists, bug trackers, and versioning systems (CVS/SVN) to deliver web systems and applications. These repositories can provide rich collections of process data, and artifacts which can be analyzed to better understand the project status.

The paper provides information of value about open‐source solutions.

Modern information systems are increasingly built on Web‐based and component‐based platforms. This raises the need for a service‐oriented infrastructure to simplify the management and procurement of corresponding components. Special focus lies on the deployment and distribution of such software artifacts within the context of the World Wide Web to promote their reuse and there‐fore to save development costs. At the same time, the integrity of the overall system must not be neglected. The use of components from third‐party vendors poses a potential security threat requiring additional care. Furthermore remains the issue of usage rights for the components and the data they provide. Flexible mechanisms can offer a huge range of different licensing models to be enforced on the runtime process. This paper presents an approach to deal with these challenges together with an implementation of a software system supporting component‐based Web portals.

Web applications are subject to continuous changes and rapid evolution triggered by increasing competition, especially in commercial domains such as electronic commerce. Unfortunately, usually they are implemented without producing any useful documentation for subsequent maintenance and evolution. Thereof, the maintenance of such systems becomes a challenging problem as the complexity of the web application grows. Reverse engineering has been heralded as one of the most promising technologies to support effective web application maintenance. This paper aims to present a reverse engineering approach that helps understanding existing undocumented web applications to be maintained or evolved.

The proposed approach provides reverse engineering rules to generate a conceptual schema from a given domain ontology by using a set of transformation rules. The reverse engineering process consists of four phases: extracting useful information; identifying a set of ontological constructs representing the concepts of interest; enriching the identified set by additional constructs; and finally deriving a conceptual schema.

The advantage of using ontology for conceptual data modeling is the reusability of domain knowledge. As a result, the conceptual data model will be made faster, easier and with fewer errors than creating it in usual way. Designers can use the extracted conceptual schema to gain a better understanding of web applications and to assist in their maintenance.

The strong point of this approach is that it relies on a very rich semantic reference that is domain ontology. However, it is not possible to make a straightforward transformation of all elements from a domain ontology into a conceptual data model because ontology is semantically richer than data conceptual models.

Rich Internet Application (RIA) technologies offer designers the opportunity to experiment with novel interaction grammars, whose implications for conceptual modeling still need to be fully understood. An open problem is the ability to characterize the fluid, smooth and organic nature of the user interaction and navigation in ways that allow web engineers to share through a common vocabulary, as well as sketch, explore and specify design decisions in the light of usability requirements and stakeholder's goals. The purpose of this paper is to address this problem.

To meet this challenge, the authors extend IDM (Interactive Dialogue Model), a dialogue‐based approach focusing on the conceptual dialogue flow with the user, codifying a set of key modeling constructs in order to describe the new dialogue features of RIAs.

The approach, called Rich‐IDM demonstrated some relevant features: expressiveness to capture interactive features at a high level of abstraction, semi‐formality to facilitate the establishment of a common ground between designers and web engineers, and traceability of the design to important usability requirements.

The paper proposes a simple way to fill the gap between hypermedia design and user experience design for RIAs, which is an open issue, both from the web engineering point of view and the human‐computer interaction point of view.

The authors have described how Rich‐IDM can help designers to capture and cope with some RIA interface flaws. In this case, the benefits of the approach are directly related to the semantics of its primitives.

The authors' proposal is the first, consolidated step of a promising research avenue.

This article proposes the concept of web clientserver event together with its associated taxonomy which yields a formal specification for such an event. The concept, in conjunction with the concept of atomic use case (reviewed in the article), is then used as a key element for a model‐driven approach to web information system development. The outcome is a new method for web information systems development that reduces the complex web‐based hypermedia navigation behaviour to a much simpler event‐driven behaviour. On the strength of that realized simplicity, the method provides (i) a set of platform‐independent models that completely characterizes the application, and (ii) a well‐defined process to map the combined model to any chosen platform‐dependent implementation.