Abstract

Abstract
Wind power integration has always been a key research area due to the green future power system target. However, the intermittent nature of wind power may impose some technical and economic challenges to Independent System Operators (ISOs) and increase the need for additional flexibility. Motivated by this need, this paper focuses on the potential of Demand Response Programs (DRPs) as an option to contribute to the flexible operation of power systems. On this basis, in order to consider the uncertain nature of wind power and the reality of electricity market, a Stochastic Network Constrained Unit Commitment associated with DR (SNCUCDR) is presented to schedule both generation units and responsive loads in power systems with high penetration of wind power. Afterwards, the effects of both price-based and incentive-based DRPs are evaluated, as well as DR participation levels and electricity tariffs on providing a flexible load profile and facilitating grid integration of wind power. For this reason, novel quantitative indices for evaluating flexibility are defined to assess the success of DRPs in terms of wind integration. Sensitivity studies indicate that DR types and customer participation levels are the main factors to modify the system load profile to support wind power integration.

Abstract
Temporal information retrieval has been a topic of great interest in recent years. Despite the efforts that have been conducted so far, most popular search engines remain underdeveloped when it comes to explicitly considering the use of temporal information in their search process. In this paper we present GTE-Rank, an online searching tool that takes time into account when ranking time-sensitive query web search results. GTE-Rank is defined as a linear combination of topical and temporal scores to reflect the relevance of any web page both in topical and temporal dimensions. The resulting system can be explored graphically through a search interface made available for research purposes.

Abstract
With the increase of the Information and Communication Technologies in all aspects and sectors of our life, a world of unprecedented scenarios is arising. Some of these scenarios are the explosions of new and different Healthcare projects that intend to decrease the economical and social costs of the real ageing population phenomenon, through the delocalization of healthcare services delivery and management to the home. These Ambient Assisted Living environments, which we have taken a step forward with the introduction of proactive techniques for better adapting to its users, usually elderly or chronic patients, are now entering a new phase: users with no special help needs also need to have a healthier Active Ageing. Since the direct correlation between physical activity and health is well established, we present here an idea to better achieve this goal. © Springer International Publishing Switzerland 2014.

Abstract
The torrefaction of biomass is a thermochemical process based on the de composition of hemicellulose, which is the dominant reaction, while the cellulose and lignin fractions remain almost unaffected. Torrefaction of biomass improves its physical properties like grindability, particle shape, size, and distribution, pelletability, and composition properties like moisture, carbon and hydrogen contents, and calorific value. The already higher energy density can be increased further by a pelletizing step after torrefaction. These improved properties make torrefied biomass particularly suitable for co-firing in power plants. Co-firing biomass with fossil fuels is one of the solutions to reduce the greenhouse gas emissions of existing power plants. Several studies on torrefaction of biomass for heat and power applications have been documented in the literature, which need to be reviewed and analyzed for further actions in the field, because significant gaps remain in the understanding of the biomass torrefaction process, which necessitate further study, mainly concerning the characterization of the torrefaction chemical reactions, investigation of equipment performance and design, and elucidation of supply chain impacts. This is the main objective of the present review study, which consists in three parts. The first part focuses on the mechanism of biomass torrefaction. It is followed by a review of biomass co-firing with coal. Finally, market opportunities for the process are discussed.

Abstract
We consider a wiretap multiple-input multiple-output multiple-eavesdropper (MIMOME) channel, where agent Alice aims at transmitting a secret message to agent Bob, while leaking no information on it to an eavesdropper agent Eve. We assume that Alice has more antennas than both Bob and Eve, and that she has only statistical knowledge of the channel towards Eve. We focus on the low-noise regime, and assess the secrecy rates that are achievable when the secret message determines the distribution of a multivariate Gaussian mixture model (GMM) from which a realization is generated and transmitted over the channel. In particular, we show that if Eve has fewer antennas than Bob, secret transmission is always possible at low-noise. Moreover, we show that in the low-noise limit the secrecy capacity of our scheme coincides with its unconstrained capacity, by providing a class of covariance matrices that allow to attain such limit without the need of wiretap coding.