Eurico Carrapatoso

A reflective component-based and architecture aware framework to manage architecture composition

Large scale distributed systems are typically evolving environments that have to deal with interoperability, scalability, mobility and QoS adaptability requirements. Generically, these systems need adaptation mechanisms to cope with short-term (cf. programmed reconfiguration) and long-term requirements (cf. evolutionary reconfiguration). We propose a reflective component-based framework with architecture style awareness for managing architecture composition and constraining adaptation. Specifically, this framework provides the necessary tools to generate and manipulate the programming model abstractions (i.e. components, connectors and respective properties and interfaces). The framework offers a principled way to deal with both introspection and adaptation of basic and composite components. It provides the developers with the ability to choose, extend and modify architecture style managers. These managers are responsible to represent and check architecture constraints both at development and deployment time, i.e. before any architectural reconfiguration may be committed.

Constructivist Approach for an Educational Adaptive Hypermedia Tool

The aim of this paper is to present an Constructivism approach for an educational adaptive hypermedia tool. The learning platform has a constructivist approach, assessing the user knowledge and presenting contents and activities adapted to the characteristics and learning style of the student. The platform allows the students and teachers to autonomously create and consolidate knowledge, with permanent automatic feedback and support, through instructional methodologies and educational activities explored in a constructivist manner.

Supporting adaptable distributed systems with FORMAware

The interactive and ubiquitous nature of future distributed services (e.g. digital libraries, learning systems, etc.) makes them more architectural and resource demanding. Consequently, next generation middleware frameworks should support both shorter and longer-term adaptation (i.e. a priori and a posteriori reconfiguration). In fact, current component standards [W. Emmerich, (2000)] leverage software reusability and diminish development costs. Nevertheless, it is also a fact that existing middleware, which succeeded in meeting the goals of heterogeneity and interoperability, is not open enough for tackling the problem of dynamic evolution. We present FORMAware, a framework that combines a novel component-based programming model enhanced by a reflective design, the former capturing the knowledge about software architecture abstractions (e.g. components, connectors, style managers, style rules) while the latter offering architecture awareness by explicitly opening the content and structure of both atomic and composite components (via introspection and adaptation meta-objects). In addition, FORMAware provides a set of tools and services for automating software development and adaptation (i.e. support for the generation, assembly, deployment and dynamic reconfiguration processes).

A Shortest Path Approach for Staff Line Detection

Many music works produced in the past still exist only as original manuscripts or as photocopies. Preserving them entails their digitalization and consequent accessibility in a digital format easy-to-manage. The manual process to carry out this task is very time consuming and error prone. Optical music recognition (OMR) is a form of structured document image analysis where music symbols are isolated and identified so that the music can be conveniently processed. While OMR systems perform well on printed scores, current methods for reading handwritten musical scores by computers remain far from ideal. One of the fundamental stages of this process is the staff line detection. In this paper a new method for the automatic detection of music stave lines based on a shortest path approach is presented. Lines with some curvature, discontinuities, and inclination are robustly detected. The proposed algorithm behaves favourably when compared experimentally with well-established algorithms.

PCMAT – Mathematics Collaborative Learning Platform

The aim of this paper is to present an Educational Adaptive Hypermedia Tool, PCMAT, Based on Progressive Assessment and adapted to the student model and learning style. The adaptation of the application is based on progressive selfassessment (exercises, tasks, etc.). The learning platform was already implemented, tested and evaluated in learning processes in Basic Schools. Also, the paper defines and evaluates the characteristic of the User Model to be used in the Student Modeling.

SAGA reloaded: Towards a generic platform for developing cooperative applications

Groupware specification and development has always been a complex task, requiring special attention to issues such as notification of cooperative actions and ensuring consistency of shared data. Some years ago SAGA was developed as a framework to build groupware applications based on a set of core web services that provide the most common cooperative functionalities. Despite its potential, the last few years brought some technological developments that placed new challenges. This paper presents a new generation of the SAGA platform that adds to the original framework features that emerged recently, namely the regulation of social interaction, incorporation of new communication technologies, connectors to several external services and interaction environments, and the addition of contextual information.

Dynamic Generation of SMIL-Based Multimedia Interfaces

The current heterogeneous world of networks and terminals combined with the generalized mobility of users pose telecommunications operators and service providers the challenge of dynamically adapt the services they provide. This paper presents a proposal to solve the problem of the adaptation of multimedia services in mobile contexts. The paper combines context-awareness techniques with user interface modeling and description to dynamically adapt telecommunications services to user resources, in terms of terminal and network conditions. The solution is mainly characterized by the approach used for resolving the existing dependencies among user interface variables, which is based on the constraints theory, and by the mechanism for acquiring the user context information, which uses the Parlay/OSA interfaces. The experiments and tests carried out with these techniques demonstrate a general improvement of the adaptation of multimedia services in mobile environments, in comparison to systems that do not dynamically integrate the user context information in the adaptation process.

PCMAT Metadata Authoring Tool

This paper introduces the PCMAT platform project and, in particular, one of its components, the PCMAT Metadata Authoring Tool. This is an educational web application that allows the project metadata creators to write the metadata associated to each learning object without any concern for the metadata schema semantics. Furthermore it permits the project managers to add or delete elements to the schema, without having to rewrite or compile any code.

PCMAT - Mathematics Collaborative Educational System

PCMAT (Mathematics Collaborative Learning Platform) is a collaborative adaptive learning tool based on progressive assessment for Mathematics in Basic Schools. The learning platform is based on a constructivist approach, assessing the user knowledge and presenting contents and activities adapted to the characteristics and learning style of the student. The intelligent behavior of such platform depends on the existence of a tentative description of the student – the student model (SM). The contents of this model and the student most prominent learning style are used by a domain and interaction model to select the most appropriate response to student actions. The SM is used to select the more appropriate learning object according to the student learning stage. However, this selection demands for the access to metadata describing the contents of the learning object. This need leaded to the application of a standard to describe the learning objects (LO). The authoring of LO corresponds to one major maintenance costs present in these applications. PCMAT is able to generate several instances of the same learning object through the parameterization of some features of the learning object. The platform is also able to process student responses in natural language. This project shows how techniques from Adaptive Hypermedia System (AHS) field can improve e-learning based systems in a basic school environment.

A semantic approach for learning objects repositories with knowledge reuse

In this paper we discuss how the inclusion of semantic functionalities in a Learning Objects Repository allows a better characterization of the learning materials enclosed and improves their retrieval through the adoption of some query expansion strategies. Thus, we started to regard the use of ontologies to automatically suggest additional concepts when users are filling some metadata fields and add new terms to the ones initially provided when users specify the keywords with interest in a query. Dealing with different domain areas and having considered impractical the development of many different ontologies, we adopted some strategies for reusing ontologies in order to have the knowledge necessary in our institutional repository. In this paper we make a review of the area of knowledge reuse and discuss our approach.