The increasing usage of multiple signalling mechanisms, with associated QoS extensions, creates several problems to commercial data networks. New and scalable approaches are required for the network operator to support this diversity. This paper discusses a highly flexible, scalable architecture for processing QoS Admission Control in public networks. The architecture relies on the cooperation of two different entities, an agent and a manager, with fully distributed implementation, and able to perform the required signalling, authorization, and admission control decisions. If required, the agent is capable of interfacing with different signalling mechanisms. Early implementation conclusions are also presented. This architecture is capable of operating with multiple QoS frameworks, with minimal added overhead.

In recent years several authors and projects have addressed the need for an architecture for collecting and managing context information. Most of the approaches have either been purely based in middlewares unable to address the heterogeneity of components and services platforms, or have been built around Web based technologies that are unable to cope with the realtime and reactiveness requirements that many context- aware use cases have. In this paper the authors propose a new Context Management Architecture able to solve these problems. Furthermore, this architecture, exploring the XMPP protocol, can be used as the basis for new developments in this area.

The increased demand for multimedia services by mobile end users in recent years have driven both Broadcast and Wireless Network operators to develop new systems and architectures for the deployment of such services. The proposed solutions are nonetheless limited either in terms of QoS or Capabilities to deliver new interactive services. This paper highlights strengths and drawbacks of the existing technologies in terms of QoS, Security and Mobility. In order to fill the gap between current solutions we propose a new architecture that builds itself on the synergies created by a heterogeneous network made of existing delivering technologies, such as 3GPP/MBMS and DVB, where services can be delivered to end-users in the most appropriate way for end-users and operators alike. A prototype implementation is further described.

Este artigo pretende divulgar o software de organização e gestão de conferências científicas Conference on the Web (CoW). Software este desenvolvido por alunos finalistas de Eng. Computadores e Telemática na cadeira de opção de 5º ano, de Ferramentas e Aplicacionais Multimédia.

The paper presents the results of the project proposed to the authors (who are the 4th year students of LECT) and shows how the specified problem has been solved. The description of the project and the basic requirements have been considered in the papers [1,2]

No âmbito da cadeira de projecto do curso de Engenharia de Computadores e Telemática, desenvolveu-se um demonstrador de mobilidade heterogénea tendo por base o projecto Europeu Moby Dick. Para além da construção do mesmo desenvolveram-se alguns pacotes de software que constituem uma mais valia para o demontrador. Por fim realizaram-se vários testes sobre o demonstrador cujos resultados são aqui apresentados.

Trends towards Next Generation Networks (NGN) are also changing the fundamental nature of TV services. Entertainment is becoming an increasingly participative experience, both with user feedback, and with user-generated content. Furthermore, the diversity of delivery mechanisms is increasing, reaching the mobile environment. The diversity of actors and technologies is now leading to a trend into IP-based content delivery, as a solution to heterogeneity management. We present an architecture for future environments, which bridges the gap between the content production and communication infrastructures, able to operate across different networks. This architecture resorts to the notion of Service Enablers deployed above evolved converged multimedia networks, based on the IP protocol. We demonstrated this architecture by laboratory prototyping.

Plastics are vital for society, but their usage has grown exponentially and contributes to the growth of pollution worldwide. The World Health Organization, WHO, already reported that microplastics (MPs) are found everywhere, in waste and fresh water, and in the air and soil. Regarding water effluents, waste-water treatment plants only minimize the problem, trapping only larger size particles. In contrast, smaller ones remain in oxidation ponds or sewage sludges, or are even released to aquifers environment. Classic procedures for MPs detection are still quite laborious, and are usually conducted off-line, involving several steps and expensive equipment. Electrical Impedance Spectroscopy, EIS, is a technique that allows the analysis of a system’s electrical response, yielding helpful information about its domain-dependent on physical-chemical properties. Due to the superficial electronegativity of MPs’ particles, EIS may allow to attain the purpose of the present work: to provide a fast and reliable method to detect/estimate MPs’ concentration in water effluents. Among the most common microplastics are Polyethylene, PE, and Polyvinyl Chloride, PVC. Using the developed setup and experimental data collection methodology, the authors could differentiate between MPs’ suspensions containing the same concentration of the different evaluated MPs, PVC and PE, and assess PVC concentration variation, in the interval between 0.03 to 0.5 g (w/w), with an error, estimated based on the obtained impedance modulus, around or below 3% for the entire stimulus signal frequency range (from 100 Hz to 40 MHz) for the PVC particles.

Neste trabalho, estudamos um modelo de formação de preços numa população com um número finito de agentes que compram e vendem uma mercadoria. A oferta desta mercadoria é exógena e os agentes são racionais uma vez que pretendem minimizar os custos de transacção. O problema em estudo é formulado como um jogo dinâmico entre N jogadores com uma condição de equilíbrio de mercado. O limite deste problema de N jogadores é um “mean field game”. Posteriormente, mostramos como reformular o nosso jogo como um problema de optimização do custo total. Mostramos a existência de uma solução usando o método direto do cálculo das variações. Por fim, mostramos que o preço é o multiplicador de Lagrange para a condição de equilíbrio entre a oferta e a procura.

Nowadays, the automation of factory floors is necessary for extensive manufacturing processes to meet the ever-increasing competitiveness of current markets. The technological advances applied to the digital platforms have led many businesses to automate their manufacturing processes, introducing robotic manipulators collaborating with human operators to achieve new productivity, manufacturing quality, and safety levels. However, regardless of the amount of optimization implemented, some quality problems may be introduced in production lines with many products being designed and produced. This project proposes a solution for feature extraction that can be applied to automatic shape- and position-detection using a 2-dimension (2D) industrial laser to extract 3-dimension (3D) data where the movement of the item adds the third dimension through the laser’s beam. The main goal is data acquisition and analysis. This analysis will later lead to the generation of trajectories for a robotic manipulator. The results of this application proved reliable given their small measurement error values of a maximum of 2 mm.