Abstract
We propose a schedulability analysis for a particular class of time division multiple access (TDAM) networks, which we label as TDAM/SS. SS stands for slot skipping, reflecting the fact that a slot is skipped whenever it is not used Hence, the next slot can start earlier in benefit of hard real-time traffic. In the proposed schedulability analysis, we assume knowledge of all message streams in the system, and that each node schedules messages in its output queue according to a rate monotonic policy (as an example). We present the analysis in two steps. Firstly, we address the case where a node is only permitted to transmit a maximum of one message per TDMA cycle. Secondly we generalise the analysis to the case where a node is assigned a budget of messages per TDMA cycle it may transmit. A simple algorithm to assign budgets to nodes is also presented.

Abstract
In a liberalized electricity market, participants have several types of contracts to sell or buy electrical energy. Increasing electricity markets liquidity and, simultaneously, providing to market participants tools for hedging against spot electricity price were the two main reasons for the appearance of those types of contracts. However, due to the payoff nonlinearity characteristic of those contracts, deciding the optimal portfolio that best adjusts to their necessities becomes a hard task. This paper presents an optimization model applied to optimal contract allocation using Particle Swarm Optimization (PSO). This optimization model consists on finding the portfolio that maximizes the electricity producer results and simultaneously allows the practice of the hedge against the volatility of the System Marginal Price (SMP). Risk management is considered through the consideration of a mean-variance optimization function. An example for a programming period is presented using spot, forward and options contracts. PSO performance in such type of problems is evaluated by comparing it with the Genetic Algorithms (GA).

Abstract

Abstract
This article presents results of device fabrication using UV processing of materials and integrated optic components produced by flame hydrolysis deposition and hybrid sol-gel technology. Photosensitive materials were employed in the fabrication of channel waveguides and channel photo-imprinted waveguides incorporating Bragg gratings through single and double-step exposure.

Abstract
A single long-period fibre grating was written in a biconical fibre taper made from standard communications step-index optical fibre, resulting in an interferometric fibre sensor device that provided a resolution of 1 × 10-4 for refractive indices in the range of 1.30 to 1.34, suggesting that these devices may be suitable for use with aqueous solutions. © IEE 2005.

Abstract
A motivação intrínseca e os seus benefícios têm sido uma das principais áreas de investigação da Psicologia do Desporto. Contudo, o mesmo não se verifica quanto ao conhecimento do modo como os comportamentos são regulados e internalizados intrinsecamente pelos indivíduos. O propósito do presente estudo foi definir a validade de aplicação do continuum de auto-determinação (Deci & Ryan, 1985) no contexto da Educação Física. Uma amostra de 1099 alunos (544 moças e 555 rapazes) com uma média de 14,66±0,75 anos de idade, respondeu a uma adaptação e tradução do questionário de Goudas, Biddle e Fox (1994) que visa medir as formas motivacionais definidas no continuum. Os procedimentos de modelação por equações estruturais evidenciaram suporte empírico para a utilização do continuum de auto-determinação na compreensão do modo como os alunos regulam intrinsecamente o seu comportamento neste contexto. São sugeridas algumas linhas de intervenção considerando os resultados obtidos.