Abstract

Abstract
Distribution Systems (DS) are usually structured as weakly-meshed but the majority of them operate with a radial topology, mainly in order to accommodate the protection coordination. Obtaining the optimal radial configuration under several criteria has been an active research topic for more than two decades. Because of the computational burden and the non-linearity of the problem, the majority of the proposed methods and techniques, single or multi-objective, use various meta-heuristics. The DS reconfiguration problem, respecting the radiality constraints, is formulated in this paper as a multi-objective Mixed-Integer Linear Programming (MILP) problem. An adequate representation of the Pareto set is produced using an improved implementation of the epsilon-constrained method. The objective is to determine the optimal radial configuration during several time intervals, minimizing the active power losses and the cost emerging from the switching operations. The proposed methodology is tested using a 16-node sample system.

Abstract
This paper investigates the gap between research into Dynamic Spectrum Access (DSA), and the standardization of these technologies, as well as ways in which coordination of standardization activities between EU funded research projects might help bridge this gap. Concretely, it first discusses the current state of standardization in CR and DSA, as well as the need for a coordinated approach to DSA standardization among European projects. It subsequently provides a short overview of the DSA and CR research landscape in Europe and briefly describes the objectives of the Cognitive Radio Standardization Initiative (CRS-i). The following sections on the paper then focus on a survey which was conducted among the 26 currently funded, Radio Access and Spectrum related EU projects, with specific analysis also performed for the CR and DSA related sub-cluster of projects. This survey provides insight into projects' current standardization activities and collaboration methods, as well as opportunities and bottlenecks for collaboration in standardization. The paper concludes that the coordination of standardization efforts, as well as specific instruments to enable the standardization of research results beyond the project lifetime, are desirable if Europe is to play a role in the global standardization of CR and DSA. Based on the survey and on close interactions with RAS cluster projects, the paper finally proposes a number of concrete coordination trajectories. © 2014 IEEE.

Abstract
In this paper we present a comprehensive analysis and a performance assessment on the transmission of digitised RF signals over optical fibre (DRoF). Specifically, a study of the impact of the ADC/DAC quantization, jitter noise and the signal attenuation caused by the sub-sampling technique and DAC frequency roll-off are addressed by means of simulation, considering the transmission of RF signals conveying QAM symbols. Additionally, an experimental evaluation of DRoF links using vertical-cavity surface-emitting lasers (VCSEL) for different optical fibre attenuation levels is also conducted. Finally, a new paradigm of DRoF systems based on well-known sigma-delta modulators (SDM) is also presented. Results show that it is possible to digitally transmit signals through a digital optical-based network and to distribute them wirelessly at the receiver side without the need for local oscillators (LO) and/or frequency up-converters. Results also show that the new sigma-delta-over-fibre concept performs similarly to conventional DRoF schemes, whilst being more competitive for either upgrading installed systems as well as for new deployments.

Abstract
Lead is a potent toxicant associated with adverse cardiovascular effects and hypertension in children. Yet, few studies have determined if autonomic dysfunction associated with lead exposure involves brain regions which regulate autonomic responses. Central autonomic nuclei such as the nucleus tractus solitarius (NTS) and hypothalamic defence area (HDA) may be particularly sensitive to lead infiltration because they are adjacent to ventricles and areas with semi-permeable blood-brain-barriers. To understand if autonomic nuclei are sensitive to lead accumulation Wistar rats were exposed to lead from the gestational period and lead levels were quantified in brain regions that regulate arterial pressure: the NTS and the HDA. Energy dispersive X-ray fluorescence (EDXRF) was used to quantify total brain lead levels and revealed no differences between exposed and control tissues; measured values were close to the detection limit (2 mu g/g). Electrothermal atomic absorption spectrometry (ETAAS) was also used, which has a greater sensitivity, to quantify lead. There was similar to 2.1 mu g/g lead in the NTS and similar to 3.1 mu g/g lead in the HDA of exposed rats, and no lead in the control rats. There were greater lead levels in the HDA (similar to 50%) as compared with the NTS. Pathology studies revealed more prominent lead granules in the HDA as compared with the NTS. Increased microglia and astrocyte activation was also noted in the NTS of lead exposed rats as compared with the HDA. Regional differences in neuro-inflammatory responses likely contribute to heterogeneous lead accumulation, with enhanced clearance of lead in the NTS. Future studies will resolve the mechanisms underpinning tissue-specific lead accumulation.

Abstract
Electricity markets are complex environments, involving a large number of different entities, playing in a dynamic scene to obtain the best advantages and profits. MASCEM (Multi-Agent System for Competitive Electricity Markets) is a multiagent electricity market simulator that models market players and simulates their operation in the market. Market players are entities with specific characteristics and objectives, making their decisions and interacting with other players. This paper presents a methodology to provide decision support to electricity market negotiating players. This model allows integrating different strategic approaches for electricity market negotiations, and choosing the most appropriate one at each time, for each different negotiation context. This methodology is integrated in ALBidS (Adaptive Learning strategic Bidding System) - a multiagent system that provides decision support to MASCEM's negotiating agents so that they can properly achieve their goals. ALBidS uses artificial intelligence methodologies and data analysis algorithms to provide effective adaptive learning capabilities to such negotiating entities. The main contribution is provided by a methodology that combines several distinct strategies to build actions proposals, so that the best can be chosen at each time, depending on the context and simulation circumstances. The choosing process includes reinforcement learning algorithms, a mechanism for negotiating contexts analysis, a mechanism for the management of the efficiency/effectiveness balance of the system, and a mechanism for competitor players' profiles definition.