Every day more and more users with different abilities and/or temporally or permanent disabilities are accessing the Web, and many of them have difficulties in reaching the desired information. However, the development of this kind of software is complicated for several reasons. Though some of them are technological, the majority are related with the need to compose different and, many times, unrelated design concerns which may be functional as in the case of most of the application’s requirements, or non- functional such as Accessibility. Even though, there is a huge number of tools and proposals to help developers assess Accessibility of Web applications, looking from the designer perspective, there is no such a similar situation. It seems that creating accessible Web sites is more expensive and complicated than creating Web sites and then assessing/modifying them. Although this feeling somehow seems to be true, addressing Accessibility at early design, not only has a significant impact on Web site quality, but also avoids subsequent efforts to return accessible fully developed applications. In this thesis, we present a novel approach to conceive, design and develop Accessible Web applications using concepts from Aspect-Orientation. In order to accomplish our goal, we provide some modelling techniques that we explicitly developed for handling the non-functional, generic and crosscutting characteristics of Accessibility. Specifically, we have enriched the UID technique with integration points to record Accessibility concerns that will be taken into account when designing the user interface. Then, by instantiating the SIG template with association tables, we work on an abstract interface model with Accessibility softgoals to obtain a concrete and accessible interface model for the Web application being developed. We use a real application example to illustrate our ideas and point out the advantages of a clear separation of concerns throughout the development life-cycle. Thus, our proposal is based on recognized design techniques, which we embedded in a software tool, in order to facilitate the transfer of the approach to the industry. / Desarrollar aplicaciones Web Accesibles es en la actualidad una necesidad. Cada día más y más usuarios con capacidades diferentes y/o discapacidades temporales o permanentes acceden a la Web, y muchos de ellos tienen dificultades especiales para obtener la información deseada. Sin embargo, el desarrollo de este tipo de software Web es complicado por varias razones. Si bien algunas de estas son de índole tecnológicas, la mayoría están relacionadas con la necesidad de componer intereses de diseño distintos y muchas veces no relacionados entre sí, los cuales a su vez pueden ser funcionales, como lo son la mayoría de los requerimientos específicos de una aplicación, o no-funcionales, como lo es la Accesibilidad. Aún existiendo hoy en día un gran número de herramientas y propuestas para ayudar a los desarrolladores en la evaluación de la Accesibilidad de las aplicaciones Web, la situación no es la misma al observar desde la perspectiva del diseñador Web. Parece ser que diseñar sitios Web accesibles es más costoso y complejo que crear sitios Web y luego evaluarlos/modificarlos. A pesar de que este sentimiento puede ser ciertamente verdadero, los beneficios al modelar la Accesibilidad en etapas tempranas del diseño superan ampliamente las necesidades de un desarrollador al implementar esa Accesibilidad. En esta tesis, presentamos un enfoque original para concebir, diseñar y desarrollar aplicaciones Web Accesibles con una modalidad Orientada a Aspectos. Para alcanzar nuestro objetivo, ofrecemos algunas técnicas de modelado que desarrollamos específicamente para manejar las características no-funcionales, genéricas y transversales de la Accesibilidad como un interés de factor de calidad. Específicamente, enriquecimos los “User Interaction Diagrams” (UIDs) con puntos de integración, los cuales usamos durante el diseño de la interfaz de usuario, para razonar y documentar la Accesibilidad en la actividad de modelado. Luego, instanciando la plantilla del “Softgoal Interdependency Graph” (SIG) con las tablas de asociación, trabajamos en el modelo de interfaz abstracta (compuesta por “ontology widgets”) para obtener un modelo de interfaz concreta y accesible de la aplicación Web en desarrollo. Para ilustrar nuestras ideas y señalar las ventajas de una clara separación de intereses durante el ciclo de vida de desarrollo, utilizamos un ejemplo de aplicación real.

Η εργασία αυτή αποτελεί συνέχεια μιας προσπάθειας για την ανάπτυξη της πύλης WEP (Web Engineering Resources Portal). Πρόκειται για ένα Μοντέλο Αναφοράς και μια Πύλη Πόρων που φιλοδοξεί να αποτελέσει ένα σημαντικό εργαλείο για το web engineering, αλλά και αναφορά στην ανάπτυξη εφαρμογών / πληροφοριακών συστημάτων παγκοσμίου ιστού και οδηγό στην ανεύρεση και κατανόηση τεχνολογιών και εργαλείων. Το κομμάτι με το οποίο θα ασχοληθούμε εδώ αφορά το τελευταίο μέρος και τον εκπαιδευτικό χαρακτήρα που επιθυμούμε να προσδώσουμε στην πύλη. Συνοπτικά, η διπλωματική εργασία κινείται σε τρεις άξονες: Πρώτον, στη μελέτη σύγχρονων δυνατοτήτων συλλογής πληροφορίας για την επιλογή των κατάλληλων εργαλείων για εισαγωγή στην πύλη και την ανάπτυξη της δικής μας μεθοδολογίας. Η διαρκής και ραγδαία αύξηση του όγκου των δεδομένων κατέστησε εμφανές το πρόβλημα της ευρέσεως και εξαγωγής της ''χρήσιμης'' ή ''επιθυμητής'' πληροφορίας, καθώς για κάθε κατηγορία ιστοεφαρμογών υπάρχει μια πληθώρα εργαλείων ανάπτυξης (τα οποία μάλιστα διαρκώς ανανεώνονται) καθιστώντας τη διαδικασία επιλογής των καταλληλότερων ιδιαίτερα επίπονη και χρονοβόρα. Δεύτερον, στην εφαρμογή της παραπάνω μεθοδολογίας εργασίας με στόχο την εισαγωγή των αντίστοιχων εργαλείων που προέκυψαν με τη μετατροπή της πληροφορίας σε XML για τη δόμηση της πύλης WEP. Εξηγούμε πως έγινε η εισαγωγή και διαχείριση περιεχομένου με χρήση της τεχνολογίας XML και πως καταλήγουμε στην υλοποίηση των παραπάνω μέσα από την πλατφόρμα του stringbeans. Τρίτον στον εκπαιδευτικό χαρακτήρα της Πύλης. Αναφερόμαστε στις έννοιες του e-learning, και τις διάφορες εναλλακτικές που υπάρχουν στο χώρο της ηλεκτρονικής μάθησης στην εποχή του Web 2.0, όπου οι χρήστες συμμετέχουν ενεργά στη συγγραφή του εκπαιδευτικού υλικού. Αναλύουμε τα χαρακτηριστικά των PLE (Personal Learning Environments) και των LMS (Learning Management Systems) και εκθέτουμε πλεονεκτήματα και μειονεκτήματά τους. Τέλος, καταλήγουμε σε μια γενική αξιολόγηση της προσπάθειάς μας, καταγράφοντας τα αποτελέσματα και τους στόχους που υλοποιήθηκαν, τα συμπεράσματα και τις προτάσεις μας. / This paper is a follow up of the previous work concerning the Web Engineering Resources Portal (shortly WEP). It consists of a Reference Model and a Resources Portal. The aim of WEP is to provide a tool for web engineering as well as a reference for the development of applications / information systems and a guide for finding and understanding web engineering technologies and tools. Here we deal with that last part and the educational aspect of WEP which we are trying to achieve. Briefly, the thesis involves three parts: Firstly, the study of modern possibilities for collecting and importing information regarding the choice of suitable tools and the development of our own methodology. The rapid growth of data volume rendered obvious the problem of finding and extracting of ''useful'' or ''desirable '' information, since there is an abundance of development tools (which are indeed constantly renewed) for every category of web application making the process of choosing the most suitable ones particularly laborious and time-consuming. Secondly, it refers to the enforcement of the above methodology aiming at the import of resultant tools with the transformation of information in XML for the layout of WEP. We explain the way the import and management of content using XML technology is completed and we come to the adaptation and implementation phase through the Stringbeans framework. Thirdly we try to highlight the educational character of WEP portal. The concept of e-learning is described and the various alternatives at the age of Web 2.0, where the users participate actively in the writing of educational material are taken into consideration. Furthermore, we analyze the characteristics of PLE (Personal Learning Environments) and LMS (Learning Management Systems) quoting advantages and disadvantages of both. Finally, we lead to a general evaluation of our effort, mentioning the results and the objectives that were achieved, the conclusions and our proposals for the future.

No description available.

Οι εφαρμογές παγκόσμιου ιστού προσφέρουν ολοένα και περισσότερες, με υψηλό βαθμό πολυπλοκότητας υπηρεσίες, σε σχέση με τους πρώτους ιστότοπους που χρησιμοποιούνταν απλά και μόνο για την προβολή πληροφοριών. Λόγω της ολοένα αυξανόμενης πολυπλοκότητας των εφαρμογών αυτών, ο σχεδιασμός, η ανάπτυξη κι η συντηρησιμότητα μιας εφαρμογής παγκόσμιου ιστού αποτελεί πλέον μια πολυσύνθετη διαδικασία την οποία καλείται να αντιμετωπίσει ο σχεδιαστής εφαρμογών παγκόσμιου ιστού. Η δουλειά του σχεδιαστή μπορεί να απλοποιηθεί με την επαναχρησιμοποίηση της εμπειρίας άλλων σχεδιαστών εφαρμογών παγκόσμιου ιστού. Η επαναχρησιμοποίηση της εμπειρίας αυτής γίνεται με χρήση σχεδιαστικών προτύπων που ορίζονται από πεπειραμένους σχεδιαστές. Αν κατά το σχεδιασμό μιας εφαρμογής χρησιμοποιηθεί κάποια μέθοδος μοντελοποίησης σε συνδυασμό με ένα σύνολο σχεδιαστικών προτύπων, η τελική εφαρμογή θα είναι πιο αποδοτική και ποιοτική. Την ίδια χρονική στιγμή η χρήση φορητών συσκευών (κινητά τηλέφωνα, pda) έχει αυξηθεί σε πολύ μεγάλο βαθμό και όλο και μεγαλύτερο είναι το ποσοστό των συσκευών που διαθέτει και σύνδεση δεδομένων με αποτέλεσμα να επιτυγχάνεται εύκολα η σύνδεση στο διαδίκτυο από την φορητή συσκευή. Το πρόβλημα που παρουσιάζεται είναι ότι σχεδόν το σύνολο από τις ιστοσελίδες έχουν δημιουργηθεί για να προβάλλονται σε πλοηγούς (browsers) σε προσωπικούς υπολογιστές που κατά κανόνα έχουν πολύ μεγαλύτερα μέσα προβολής (οθόνες) σε σχέση με τις φορητές συσκευές. Στα πλαίσια της παρούσας διπλωματικής εργασίας μελετούνται οι μέθοδοι μοντελοποίησης που έχουν προταθεί από την ερευνητική κοινότητα και τα σχεδιαστικά πρότυπα που έχουν οριστεί καθώς και οι τεχνικές αποτελεσματικής σχεδίασης εφαρμογών διαδικτύου για φορητές συσκευές (τεχνικές αντιστροφής μηχανίκευσης, μετασχηματισμός μοντέλου για προβολή σε φορητές συσκευές, αυτόματη παραγωγή εφαρμογής παγκοσμίου ιστού από το μοντέλο). / Web Applications provide many services and they are not used just to display content, as it was the case for the first web sites. Due to the growing complexity of these applications, the design, development and maintenance of web applications has become a complex process that the software architect has to face. The job of the software architect can be simplified by reusing the experience of others developers/ designers/ software architects. This reuse is achieved by means of design patterns that have been defined by experts. If, we make use of a modeling method in combination with design patterns when designing a web application, the final result will be more efficient and qualitative. At the same time the use of portable devices (mobile phones, pda) has grown enormously. The percentage of available devices with data connection available is increasing. As a result, it is easy to connect to Internet from a portable device. As part of this thesis, we study the modeling methods and the and design standards proposed by the research community. Moreover we study the methods for designing effectively information systems for the support of mobile applications (reverse engineering, transformation model for viewing on mobile devices, auto generate web applications based on model etc).

Com a popularização da Web 2.0 e RIA - Rich Internet Applications, as aplicações web cada vez mais utilizam-se da linguagem JavaScript, para implementar recursos de interação sofisticados e complexos na plataforma da Web, visando atrair os usuários com experiências que agradem e atendam suas expectativas. Uma vez que esses recursos de RIA, muitas vezes, fornecem feedback visual de mudanças realizadas na interface, usuários que interagem com a Web por meio de Tecnologias Assistivas, como leitores de tela, não são capazes de identificar e interagir corretamente com os componentes de interface. Assim, a WAI - Web Accessibility Initiative propôs a especificação ARIA - Accessible Rich Internet Applications que determina um conjunto de propriedades que atribuem semântica aos elementos de um componente de interface (Widget), permitindo que as Tecnologias Assistivas identifiquem previamente o comportamento dos componentes de interface e informem o usuário sobre as alterações que possam ser realizadas na estrutura da página web. Nesse contexto, esta tese teve como objetivo elaborar estratégias de avaliação automática dos requisitos de acessibilidade da especificação ARIA. Foram elaboradas três diferentes abordagens para analisar os requisitos da especificação ARIA, utilizando a metodologia de pesquisa-ação com a condução de três ciclos das atividades de planejar, agir, descrever e avaliar. As abordagens foram desenvolvidas com base em Testes de Aceitação e verificações de características tecnológicas das aplicações web, considerando especificamente o modelo de interação de usuários deficientes visuais que utilizam leitores de tela. Cada uma das abordagens foi validada separadamente e os resultados apresentam tendências de que as estratégias são capazes de avaliar corretamente o comportamento esperado de uma aplicação rica de Internet acessível, segundo as recomendações ARIA para usuÁ¡rios deficientes visuais. As abordagens também apresentaram como contribuições: a inclusão do modelo de interação do usuário no processo de avaliação e levantamentos sobre os níveis de conformidade de aplicações web e bibliotecas JavaScript com a especificação ARIA. Os resultados obtidos a partir das abordagens propostas nesta tese contribuem para o processo de Engenharia Web de aplicações ricas de Internet acessíveis / With the increased popularity of the Web 2.0 and RIA - Rich Internet Applications, web applications rely more and more in JavaScript to implement richer and more complex interaction mechanisms in the Web platform. Since these mechanisms, frequently, generate dynamic updates to the DOM - Document Object Model structure of a webpage and require visual perception of users to notify them about these changes in the interface, users that interact with the Web through usage of Assistive Technologies such as a screen reader are not capable of correctly identifying and interacting with the interface components built with these technologies - the widgets. In this context, the WAI - Web Accessibility Initiative created the ARIA - Accessible Rich Internet Applications specification which describes the use of properties that add semantics to elements that compose a widget, allowing Assistive Technology to priorly identify the behavior of a widget and inform the user about changes that might be made to the DOM structure of the webpage. This thesis goal was to elaborate automatic evaluation strategies for accessibility requirements of the ARIA specification. Three evaluation strategies were elaborated following the research-action methodology with the conduction of three cycles of the activities of planning, acting, describing and evaluating. The strategies were implemented based in Acceptance Tests and verifications on specific details of the technology that compose web applications, considering specifically blind users interaction patterns through the use of screen readers. Each strategy was separately validated and the results show tendencies that the strategies were capable of correctly evaluating the behavior of web applications, considering their conformance with ARIA recommendations for blind users. The development and validation of the evaluation strategies also presented contributions by: including user interaction models in the automatic evaluation approaches and presenting a survey on web applications and JavaScript toolkits conformance rates with the ARIA specification. Thus contributing to the Web Engineering process of ARIA

A literatura relata que a produção de aplicações Web apresenta problemas de baixa qualidade nas aplicações desenvolvidas, não-cumprimento de prazo e orçamento, desenvolvimento ad hoc, caótico e desestruturado. Acrescente-se que diferentes disciplinas e áreas do conhecimento, com abordagens e metodologias próprias, estão envolvidas com esse tipo de produção. Verifica-se que aplicações Web são desenvolvidas por profissionais de Software, Design, Comunicação e Mídia, entre outros. Uma área do conhecimento denominada Engenharia Web foi criada para enfocar estas questões, entretanto, ainda não está consolidada. O presente trabalho tem como objetivo apresentar diretrizes para a definição do processo de produção de aplicações Web, a partir de uma abordagem sistêmica deste, na qual as diferentes disciplinas, papéis e atividades são correlacionados na fase de concepção do projeto. Utiliza-se como método de pesquisa a revisão bibliográfica e, a partir desta, estudos de caso e pesquisa-ação para a formação de um modelo teórico. Este abstrai os aspectos fundamentais das principais disciplinas envolvidas na produção de aplicações Web e permite a instanciação de um processo adequado às particularidades de diferentes projetos. O trabalho identifica um espaço de projeto formado pelas dimensões Forma, Função, Informação e Tecnologia, relacionadas, por sua vez, às principais disciplinas envolvidas na produção de aplicações Web: Design, Engenharia de Software, Comunicação e Mídia. Conclui-se que, em função do(s) padrão(ões) de projeto utilizado(s), existe um enfoque mais adequado para o processo de produção, orientado sobre uma ou mais dimensões do espaço de projeto, bem como um papel centralizador, focado em uma disciplina, que permite o projeto evoluir mais rapidamente a um nível esperado de qualidade. / The literature relates that Web applications production presents problems like: low quality; ad-hoc, chaotic and unstructured process; budget and time overlap. Moreover, different disciplines and knowledge areas, with particular approaches and methodologies, contribute with this kind of production. It is verified that Web applications are developed by professionals of Software, Design Communication & Media, and others. A particular knowledge area called Web Engineering was developed to focus these questions; however, it is not consolidated yet. This work has as objective to present guidelines to the definition of the Web applications production process, directed by a systemic approach to this process, on that the different disciplines, roles and activities are correlated, in the conception phase. The research method utilizes bibliographic review and than, cases studies and action-research to create a theoretical model. This model abstracts the fundamental aspects of the involved disciplines in the Web applications production and enables a process instantiation, adequate to the particularities of different projects. The work identifies a design space formed by the dimensions Form, Function, Information and Technology, related to the main disciplines involved in Web applications production: Design (styling), Software Engineering and Communication & Media. It concludes that, guided by design patterns utilized, a best fit production process approach can be found, oriented on one or more dimensions of the design space, as well as a centralizer role, focused in a discipline. This approach allows to the project a quick evolution to the expected quality level.

When considering the addition of a mobile presentation channel to an existing web-based application, project managers should know how the mobile channel|s characteristics will impact the user experience and the cost of using the application, even before development begins. The PETTICOAT (Performance Tuning and cost discovery of mobile web-based Applications) approach presented here provides decision-makers with indicators on the economical feasibility of mobile channel development. In a nutshell, it involves analysing interaction patterns on the existing stationary channel, identifying key business processes among them, measuring the time and data volume incurred in their execution, and then simulating how the same interaction patterns would run when subjected to the frame conditions of a mobile channel. As a result of the simulation, we then gain time and volume projections for those interaction patterns that allow us to estimate the costs incurred by executing certain business processes on different mobile channels.

This study investigated the use of systems development methodologies in Web-based application development in South Africa. Web-based systems differ from traditional information systems by integrating different media for knowledge representation and utilizing hypertext functionality. By doing this, Web-based systems not only support creation, integration, analysis, and distribution but also storage and transfer of knowledge of business transactions within a structured information system. There are numerous methodologies available to develop Web-based systems. In this study five of these methodologies were discussed. The methodologies include Web IS Development Methodology (WISOM), Internet Commerce Development Methodology (ICOM), Web Engineering, Extreme Programming and the Relationship Management Methodology (RMM). In this study a qualitative research approach was followed. Case studies were done on three different organizations in the South African marketplace. Semi-structured interviews were used for data collection at each organization. The interviews were transcribed, and the data were analysed using content analysis and cross-case analysis. One of the main goals of this research was to determine "how" system development methodologies are used in practice to develop Web-based systems, and to what extent it is used. The research pointed out that those organizations who participated in this study in South Africa mainly use in-house developed methodologies to develop Web-based systems, and that these organizations adhere strictly to their methodology. The main reasons organizations choose to use methodologies are that methodologies aid in the delivery of a better quality Web-based system, and also act as a good project management mechanism within the organization. / Thesis (M.Com. (Computer Science))--North-West University, Potchefstroom Campus, 2007

Thesis (M.Com. (Computer Science))--North-West University, Potchefstroom Campus, 2007.

Web applications offering real-time collaboration support (e.g. Google Docs) allow geographically dispersed users to edit the very same document simultaneously, which is appealing to end-users mainly because of two application characteristics. On the one hand, provided real-time capabilities supersede traditional document merging and document locking techniques that distract users from the content creation process. On the other hand, web applications free end-users from lengthy setup procedures and allow for instant application access. However, implementing collaborative web applications is a time-consuming and complex endeavor since offering real-time collaboration support requires two specific collaboration services. First, a concurrency control service has to ensure that documents are synchronized in real-time and that emerging editing conicts (e.g. if two users change the very same word concurrently) are resolved automatically. Second, a workspace awareness service has to inform the local user about actions and activities of other participants (e.g. who joined the session or where are other participants working). Implementing and integrating these two collaboration services is largely ine cient due to (1) the lack of necessary collaboration functionality in existing libraries, (2) incompatibilities of collaboration frameworks with widespread web development approaches as well as (3) the need for massive source code changes to anchor collaboration support. Therefore, we propose a Generic Collaboration Infrastructure (GCI) that supports the e cient development of web-based groupware in various ways. First, the GCI provides reusable concurrency control functionality and generic workspace awareness support. Second, the GCI exposes numerous interfaces to consume these collaboration services in a exible manner and without requiring invasive source code changes. And third, the GCI is linked to a development methodology that e ciently guides developers through the development of web-based groupware. To demonstrate the improved development e ciency induced by the GCI, we conducted three user studies encompassing developers and end-users. We show that the development e ciency can be increased in terms of development time when adopting the GCI. Moreover, we also demonstrate that implemented collaborative web applications satisfy end-user needs with respect to established software quality characteristics (e.g. usability, reliability, etc.). / Webbasierte, kollaborative Echtzeitanwendungen (z.B. Google Docs) erlauben es geografisch verteilten Nutzern, Dokumente gemeinschaftlich und simultan zu bearbeiten. Die Implementierung kollaborativer Echtzeitanwendungen ist allerdings aufwendig und komplex, da einerseits eine Nebenläufigkeitskontrolle von Nöten ist und andererseits die Nachvollziehbarkeit von nicht-lokalen Interaktionen mit dem gemeinsamen virtuellen Arbeitsraum gewährleistet sein muss (z.B. wer editiert wo). Um die Entwicklung kollaborativer Echtzeitanwendungen effizient zu gestalten, wurde eine Generische Kollaborationsinfrastruktur (GKI) entwickelt. Diese GKI stellt sowohl eine Nebenläufigkeitskontrolle als auch Komponenten zur Nachvollziehbarkeit von nicht-lokalen Interaktionen auf eine wiederverwendbare und nicht-invasive Art und Weise zur Verfügung. In drei dedizierten Studien, die sowohl Entwickler als auch Endanwender umfassten, wurde die Entwicklungseffizienz der GKI nachgewiesen. Dabei wurde die Entwicklungszeit, der Umfang des Quelltextes als auch die Gebrauchstauglichkeit analysiert.