Abstract
Technology has profoundly changed the way we learn and live. Indeed, such relationship appears to be quite complex, within IT contexts, and especially in socially and technologically rich learning environments, where related skills and learning are progressively required and fostered. Thus, if a satisfactory level of intellectual performance and social competence of a primary school pupil is indeed highly dependent on the type of participation that parents offer their children, IT, in general, and Internet, in particular, may well provide a new paradigm, setting forth that education and communication approach is truly more complex than ever before. It is on the basis of such paradigm that we therefore present a case study where a set of multimedia exercises were used in order to possibly improve the mathematical skills of pupils, one with mental retardation and another with cerebral palsy. Being part of a Web-based system to support students' learning, the referred set of multimedia exercises proved to be the children's favorite, rather than exercises in paper form, which also led the children to show a fair more positive attitude towards learning. Also, we observed that through the mentioned multimedia exercises, the children became far more autonomous, interested, persistent, happy, and able to easily absorb the material as well as more willingly to continue on working.

Abstract
Parallel manipulators have attracted the attention of researchers from different areas such as: high-precision robotics, machine-tools, simulators and haptic devices. The choice of a particular structural configuration and its dimensioning is a central issue to the performance of these manipulators. A solution to the dimensioning problem, normally involves the definition of performance criteria as part of an optimization process. In this paper the kinematic design of a 6-dof parallel robotic manipulator for maximum dexterity is analyzed. The condition number of the inverse kinematic jacobian is defined as the measure of dexterity and solutions that minimize this criterion are found through a genetic algorithm formulation. Subsequently a neuro-genetic formulation is developed and tested. It is shown that the neuro-genetic algorithm can find close to optimal solutions for maximum dexterity, significantly reducing the computational load.

Abstract
The middleware is an important software component when designing an application, facilitating the development and deployment of the applications. In the case of Distributed Embedded Systems (DES), the middleware should provide basic functionalities to abstract the complexity that results from network distribution, namely data consistency, events synchronization and resource management. Often DES applications exhibit real-time requirements and have to deal with dynamic environments that present evolving requirements. While some middleware architectures have been proposed to address resource provisioning and QoS management, none of those middle-wares supports dynamic resource reconfiguration while providing real-time guarantees. This paper proposes a middleware layer, based on the services provided by a flexible real-time communication protocol, addressing distribution abstraction, dynamic reconfiguration and dynamic QoS management under real-time constraints.

Abstract
The international Electrotechnical Commission (IEC) 61499 architecture incorporated several function block with which distributed control application may be developed, and how these are interpreted and executed. However, due the distributed nature of the control applications, many issues also need to be taken into account. Most of these are due to the new error model and failure modes of the distributed hardware on which the distributed application is executed and also due the incomplete standards definition of the execution models. IEC 61499 frameworks does not clarify how to handle with replication of software and hardware components. In this paper we propose a replication model for IEC 61499 applications and which mechanisms and protocols may be used for their support.

Abstract
In the last years many standards have been created for the industrial control domain. Some have found wide adoption in the industiy, while others seem to never leave the stage of a promising technology. An example of the first type is ISA 88, that defines an architectural design for control applications for the batch process industiy. The author is of the opinion that IEC 61499 is an example of the latter. In this paper the author analyzes how the design architecture defined in ISA 88 may be implemented using the programming framework defined in IEC 61499. Even though ISA 88 and IEC 61499 both follow an event based and object-oriented approach, the author uncovers a fundamental constraint of the IEC 61499 related to the dynamic invocation of services from distinct object instances. Without tiying to extend the IEC 61499 standard, two approaches are presented to work around this constraint.

Abstract
The IEC (International Electrotechnical Commission) 61131-3 standard defines several programming languages which may be used to develop industrial control applications. These applications typically execute on industrial PLCs (Programmable Logic Controller). PLC vendors have embraced the first version of this standard [3], with each vendor adopting it at its own pace. As the standard is implemented, several deficiencies have been uncovered. In this paper deficiencies identified by the authors during the implementation of a compiler, compliant with the second version of the standard 141, are explained and analysed. Other deficiencies identified by other authors have also been aggregated and explained. For each deficiency, one or more suggestions (including changes to the formal syntax definition) are made as to how the standard could be changed in order to rectify the deficiency.