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Universidad de Sevilla. Grado en Comunicación Audiovisua

Optimization of unequal error protection AL-FEC scheme via adapted simulated annealing

We adapt simulated annealing for speeding up the search of optimal configurations for protecting video transmission over IP networks. The considered protection scheme is a version of the Pro-MPEG COP3 FEC codes, consisting in using several matrices of unequal size per FEC block

Adaptive protection scheme for MVC-encoded stereoscopic video streaming in IP-based networks

We present an adaptive unequal error protection (UEP) strategy built on the 1-D interleaved parity Application Layer Forward Error Correction (AL-FEC) code for protecting the transmission of stereoscopic 3D video content encoded with Multiview Video Coding (MVC) through IP-based networks. Our scheme targets the minimization of quality degradation produced by packet losses during video transmission in time-sensitive application scenarios. To that end, based on a novel packet-level distortion model, it selects in real time the most suitable packets within each Group of Pictures (GOP) to be protected and the most convenient FEC technique parameters, i.e., the size of the FEC generator matrix. In order to make these decisions, it considers the relevance of the packet, the behavior of the channel, and the available bitrate for protection purposes. Simulation results validate both the distortion model introduced to estimate the importance of packets and the optimization of the FEC technique parameter values

Identifying past social-ecological thresholds to understand long-term temporal dynamics in Spain

A thorough understanding of long-term temporal social-ecological dynamics at the national scale helps to explain the current condition of a country’s ecosystems and to support environmental policies to tackle future sustainability challenges. We aimed to develop a methodological approach to understand past long-term (1960-2010) social-ecological dynamics in Spain. First, we developed a methodical framework that allowed us to explore complex social-ecological dynamics among biodiversity, ecosystem services, human well-being, drivers of change, and institutional responses. Second, we compiled 21 long-term, national-scale indicators and analyzed their temporal relationships through a redundancy analysis. Third, we used a Bayesian change point analysis to detect evidence of past social-ecological thresholds and historical time periods. Our results revealed that Spain has passed through four socialecological thresholds that define five different time periods of nature and society relationships. Finally, we discussed how the proposed methodological approach helps to reinterpret national-level ecosystem indicators through a new conceptual lens to develop a more systems-based way of understanding long-term social-ecological patterns and dynamicsThis work was supported by the Biodiversity Foundation (http://www.fundacion-biodiversidad.es/) of the Spanish Ministry of Agriculture, Food and Environment. Partial financial support was also provided by the Ministry of Economy and Competitiveness of Spain (project CGL2014-53782-P: ECOGRADIENTES). The Spanish National Institute for Agriculture and Food Research and Technology (INIA) funded Marina García-Llorente as part of the European Social Fund. Blanca González García-Mon participated in this article as a “la Caixa” Banking Foundation scholar. The funders had no role in the study design, data collection and analysis, preparation of the report, or the decision to submit the study for publicatio

Oligosacáridos utilizados para inhibir la mitosis de los astrocitos y de las células tumorales del sistema nervioso; y procedimiento de obtención de estos oligosacáridos

Traducción de Patente Europea E92923821 (fecha de solicitud, 13/11/1992).-- Prioridad: ES199111139102522.-- Titular: Consejo Superior de Investigaciones Científicas (CSIC).La invención se refiere a oligosacáridos y a preparaciones medicinales que contienen ingredientes orgánicos activos.Peer reviewe

Perceptual distortion modeling for side-by-side 3D video delivery

A frame-level distortion model based on perceptual features of the human visual system is proposed to improve the performance of unequal error protection strategies and provide better quality of experience to users in Side-by-Side 3D video delivery systems

ViCoCoS-3D: Videoconferencing common scenes

This paper presents a 3D video dataset containing sequences with typical content from videoconferencing scenarios. The objective of this dataset is to provide freely-available sequences for the research community to support the develop-ment and evaluation of processing techniques applicable to 3D videoconferencing systems. Therefore, a detailed description of the generation process and the content characteristics is provided, together with insights of possible applications of the datase

Electrochemical sensors modified with combinations of sulfur containing phthalocyanines and capped gold nanoparticles: A study of the influence of the nature of the interaction between sensing materials

Producción CientíficaVoltametric sensors formed by the combination of a sulfur-substituted zinc phthalocyanine (ZnPcRS) and gold nanoparticles capped with tetraoctylammonium bromide (AuNPtOcBr) have been developed. The influence of the nature of the interaction between both components in the response towards catechol has been evaluated. Electrodes modified with a mixture of nanoparticles and phthalocyanine (AuNPtOcBr/ZnPcRS) show an increase in the intensity of the peak associated with the reduction of catechol. Electrodes modified with a covalent adduct-both component are linked through a thioether bond-(AuNPtOcBr-S-ZnPcR), show an increase in the intensity of the oxidation peak. Voltammograms registered at increasing scan rates show that charge transfer coefficients are different in both types of electrodes confirming that the kinetics of the electrochemical reaction is influenced by the nature of the interaction between both electrocatalytic materials. The limits of detection attained are 0.9 × 10−6 mol∙L−1 for the electrode modified with the mixture AuNPtOcBr/ZnPcRS and 1.3 × 10−7 mol∙L−1 for the electrode modified with the covalent adduct AuNPtOcBr-S-ZnPcR. These results indicate that the establishment of covalent bonds between nanoparticles and phthalocyanines can be a good strategy to obtain sensors with enhanced performance, improving the charge transfer rate and the detection limits of voltammetric sensors.Ministerio de Economía, Industria y Competitividad - Fondo Europeo de Desarrollo Regional (projects RTI2018-097990-B-I00 / CTQ2017-87102-R)Junta de Castilla y Leon - Fondo Europeo de Desarrollo Regional (project VA275P18

Novel Multi-Feature Bag-of-Words Descriptor via Subspace Random Projection for Efficient Human-Action Recognition

Human-action recognition through local spatio-temporal features have been widely applied because of their simplicity and its reasonable computational complexity. The most common method to represent such features is the well-known Bag-of-Words approach, which turns a Multiple-Instance Learning problem into a supervised learning one, which can be addressed by a standard classifier. In this paper, a learning framework for human-action recognition that follows the previous strategy is presented. First, spatio-temporal features are detected. Second, they are described by HOG-HOF descriptors, and then represented by a Bag of Words approach to create a feature vector representation. The resulting high dimensional features are reduced by means of a subspace-random-projection technique that is able to retain almost all the original information. Lastly, the reduced feature vectors are delivered to a classifier called Citation K-Nearest Neighborhood, especially adapted to Multiple-Instance Learning frameworks. Excellent results have been obtained, outperforming other state-of-the art approaches in a public database

Mapping and assessing ecosystem services: Methods and practical applications

The EU Biodiversity Strategy to 2020 called on EU member states to map and assess the state of ecosystems and their services in their national territory (European Commission 2011). This knowledge-base should be designed to be a primary resource for developing Europe’s green infrastructure, to identify areas for ecosystem restoration and to set a baseline against which the goal of ‘no net loss” of biodiversity and ecosystem services can be evaluated. Thus, appropriate methods, information and data are needed to know where and how, for example, food, water, clean air, other materials and recreation are provided, and how climate, nutrients, natural disasters, pests and diseases are regulated. Information and data on actual ecosystem services (ES) demands, beneficiaries and potential mismatches with their supply location as well as ES quality and quantity are essential to make informed decisions for appropriate management of natural resources. ES are a very complex topic and their integrative assessment and implementation asks for truly transdisciplinary approachesThe ESMERALDA project received funding from the European Union’s Horizon 2020 research and innovation programme: grant agreement No 64200