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Updated: 1 hour 2 min ago
1 hour 2 min ago
Title: Efficient margin adaptive scheduling for MIMO-OFDMA systems
Authors: Moretti, Marco; Pérez Neira, Ana Isabel
Abstract: In this paper we address the problem of margin adaptive scheduling in the downlink of an orthogonal frequency division multiple access (OFDMA) multiple-input multiple-output (MIMO) system. Optimal resource allocation in MIMO systems requires the joint optimization of: a) linear transmit and receive spatial filters, b) channel assignment and c) power allocation. This problem is not convex and its complexity becomes thus intractable already for small sets of users and subcarriers. To reduce the complexity of the problem at hand, we propose a novel heuristic strategy that partitions the users in different groups according to their average channel quality and addresses the original problem by solving a succession of lower-complexity allocation problems. The spatial dimension is employed to prevent multiple access interference from hindering the performance of the sequential allocation. To further reduce the complexity burden we introduce a linear programming formulation in combination with a waterfilling-based strategy to allocate channels and power to the groups of users. Numerical results and evaluation of the computational complexity show that, though suboptimal, in most cases the proposed algorithm manages to exploit in an original way the inherent multi-user diversity of multi-carrier systems to ease the task of resource allocation with a very limited performance loss from the theoretic optimum.
1 hour 2 min ago
Title: Rehabilitación energética de edificios escolares en clima mediterráneo: caso de estudio, Barcelona
Authors: Bosch González, Montserrat; Rodríguez Cantalapiedra, Inma; Álvarez del Castillo, Javier
Abstract: necesidad de reducir el consumo energético se hace cada día más evidente,
especialmente en Europa debido a su situación de dependencia energética de países
externos a la Unión y también por razones relacionadas con el impacto ambiental y las
emisiones asociadas.
En este contexto, la rehabilitación energética de edificios es una línea de trabajo
prioritaria que actúa sobre el parque edificado, y los edificios públicos deben ser un
modelo o ejemplo para impulsar este tipo de actuaciones. Los centros docentes, con un
potencial de ahorro muy importante y con unos consumos energéticos asociados
básicamente a dos grandes conceptos, la iluminación y la climatización, pueden
considerarse como un laboratorio de investigación en cuanto a eficiencia energética.
A partir de las experiencias adquiridas durante más de 10 años se ha desarrollado
una metodología de análisis para la intervención en edificios docentes en Barcelona con
los siguientes objetivos: definir los indicadores estratégicos para identificar las
oportunidades de ahorro, evaluar las posibles medidas de reducción de consumos a partir
de la limitación de la demanda, analizar y dar contenido al papel de cada uno de los
actores que intervienen en las estrategias de uso y gestión de los edificios escolares y
establecer los criterios que deben considerarse para realizar las futuras intervenciones de
rehabilitación energética.
El método, como manera de pensar ordenadamente, ha de permitir optimizar los
recursos y descubrir les rutas de trabajo que nos conduzcan al objetivo final: reducir el
consumo energético del parque edificado
1 hour 2 min ago
Title: Performance assessment & synergic operation of algorithmic solutions enabling opportunistic networks– D4.2
Authors: Demestichas, Panagiotis; Pérez Romero, Jordi; Sallent Roig, José Oriol; Bouali, Faouzi; Ferrús Ferré, Ramón Antonio; Karvounas, Dimitrios; Georgakopoulos, Andreas; Stavroulaki, Vera; Tsagkaris, Kostas; Riaz, Maryam; Bourdellès, Michel; Vahid, Seiamak; Gebert, Jens; Fuchs, Rolf; Moreno, Oscar; Matinmikko, Marja; Sarvanko, Heli; Boskovic, Dragan; Tosic, M.; Alnwaimi, Ghassan; Rakotoharison, Lanto; Panaitopol, Dorin; Bagayoko, Abdoulaye; Mouton, Christian; Lee, Haeyoung; Shariat, Shahin
Abstract: Deliverable D4.2 del projecte europeu OneFIT
1 hour 2 min ago
Title: Informe socio-residencial del barrio centro de Fuenlabrada
Authors: Garcia-Almirall, M. Pilar
Abstract: INFORME SOCIO-RESIDENCIAL DEL BARRIO CENTRO DE FUENLABRADA
1 hour 2 min ago
Title: MEET: Motif Elements Estimation Toolki
Authors: Pairó Castiñeira, Erola; Maynou Fernández, Joan; Vallverdú Ferrer, Montserrat; Gallardo Chacón, Joan Josep; Caminal Magrans, Pere; Marco Colás, Santiago; Perera Lluna, Alexandre
Abstract: MEET (Motif Elements Estimation Toolkit) es un paquete en R que integra un conjunto de algoritmos para la detección computacional de los puntos de unión de los factores
de transcripción (TFBS). El paquete en R MEET incluye cinco programas de búsqueda de motivos: MEME/MAST (Multiple Expectation-Maximization for Motif Elicitation), Q-residuals, MDscan (Motif Discovery scan), ITEME (Information Theory Elements for Motif Estimation) y Match. Además, permite al usuario trabajar con diferentes algoritmos de alineamiento múltiple: MUSCLE (Multiple Sequence Comparison by Log-Expectation), ClustalW y MEME. El paquete puede trabajar
en dos modos diferentes, entrenamiento y detección. El modo entrenamiento permite escoger los parámetros óptimos del detector escogido. Y el modo detección permite, una vez escogidos los parámetros, analizar un genoma en busca de puntos de unión. Además, ambos modos pueden combinar los diferentes métodos de alineamiento y de detección, permitiendo al usuario un amplio abanico de posibilidades. Esta característica permite comparar los diferentes métodos computacionales al mismo nivel,sin realizar ningún agravio comparativo debido
al alineamiento.
1 hour 2 min ago
Title: El Santuari de Nostra Sra. de la Misericòrdia de Canet de Mar: història i arquitectura
Authors: Meca Acosta, Benito; Rosselló i Nicolau, Maribel; Alcalde Vilà, Sergi
Abstract: El Santuari de Nostra Sra. de la Misericòrdia de Canet de Mar: història i arquitectura
1 hour 2 min ago
Title: Poster CONSTRUMAT Start-up Panel
Authors: Burns, Malcolm
Abstract: Poster CONSTRUMAT Start-up Panel
1 hour 2 min ago
Title: Wahrnehmung des Raumes : Malerei um 1800
Authors: Usandizaga Calparsoro, Miguel M.
1 hour 2 min ago
Title: Literature revision_Agent-based models
Authors: Chica Mejía, Juan Eduardo
Abstract: Literature revision_Agent-based models
1 hour 2 min ago
Title: Modelling shoreline sand waves: application to the coast of Namibia
Authors: Falqués Serra, Albert; Van den Berg, Niels; Ribas Prats, Francesca; Caballeria Suriñach, Miquel
Abstract: The SW coast of Africa (Namibia and part of Angola) features very long sandy beaches and a wave climate dominated by energetic swells from the SSW, therefore approaching the coast with a very high obliquity. Satellite images reveal that along that coast there are many shoreline sand waves with wavelengths ranging from 2 to 8 km. A more detailed study, including a Fourier analysis of the shoreline position, confirms a high spectral density concentration at these lengths scales. Also, it becomes apparent that at least some of the sand waves are dynamically active rather than being controlled by the geological setting. A morphodynamic model is used to test the hypothesis that these sand waves could emerge as free morphodynamic instabilities of the coastline due to the obliquity in wave incidence. It is found that the wave period, Tp, is crucial to establish the tendency to stability or instability, instability increasing for decreasing period, whilst there is some discrepancy in the observed periods. Model results for Tp = 7 s clearly show the tendency for the coast to develop free sand waves at 2 km wavelength within a few years, which migrate to the north at rates of 0.6-0.7 km/yr. For Tp = 8 s, instability is weaker and rather sensitive to other factors as the underlying bathymetry. In this case, the coast seems to be nearly at neutral stability so that sand waves originated from other mechanisms can propagate downdrift with little decay.
1 hour 2 min ago
Title: Delimitación de los sistemas urbanos de la costa ibérica: España y Algarve (Portugal)
Authors: Moix Bergadà, Montserrat
Abstract: DELIMITACIÓN DE LOS SISTEMAS URBANOS DE LA COSTA IBÉRICA: ESPAÑA Y ALGARVE (PORTUGAL)
1 hour 2 min ago
Title: Dictamen técnico estructural
Authors: Muñoz Salinas, Francisco
Abstract: Dictamen estructural para determinar el estado de la estructura de un edificio y si ella pudo ser la causa de unas
supuestas patologías en el edificio de viviendas plurifamiliar ubicado en la calle GERMANS
THOS Y CODINA nº 6 de Mataró en la provincia de Barcelona, España.
Fri, 17/05/2013 - 18:31
Title: A procedure to design wide-band electromagnetically-coupled stacked microstrip antennas based on a simple network model
Authors: Anguera Pros, Jaume; Puente Baliarda, Carles; Borja, C.
Abstract: It is well known that microstrip patch antennas have a poor bandwidth due to the small spacing between the patch and the ground plane. A stacked patch configuration has been demonstrated experimentally as a feasible solution, but little information on the design procedure is available. Here, a systematic design procedure based on a single network model is shown.
Fri, 17/05/2013 - 18:28
Title: Iterative network models to predict the performance of Sierpinski fractal antennas and networks
Authors: Borja, C.; Puente Baliarda, Carles
Abstract: Two simple, fast numerical models to predict the input parameters of antennas and networks whose topologies are that of the Sierpinski gasket and carpet fractal shape, are introduced. These models are based on the same recursive principle used to generate fractal structures.
Fri, 17/05/2013 - 17:07
Title: Leer y comprender la ciudad
Authors: Franquesa Sànchez, Jordi
Abstract: Este artículo pretende poner de relieve y valorar cómo diferentes medodologías de
aprendizaje implementadas en las aulas de taller pueden mejorar sensiblemente la capacidad de razonamiento crítico del alumno, aumentando así sus aptitudes para poder resolver determinados problemas que se le puedan presentar en la disciplina del urbanismo.
Fri, 17/05/2013 - 16:55
Title: ONU optimal gain and position of the distribution element in Rayleigh-limited WDM and TDM PONs with reflective ONU
Authors: López Pastor, Eduardo Tommy; Lázaro Villa, José Antonio; Arellano Pinilla, Cristina; Polo Querol, Víctor; Prat Gomà, Josep Joan
Abstract: The influence of the distribution element position in PONs is reported. Best Crosstalk-to-Signal ratio (C/S) is achieved if it is placed either in the ONU or OLT vicinity with optimum ONU gain depending of the MUX position
Fri, 17/05/2013 - 16:48
Title: Segmentation robust to the vignette effect for machine vision systems
Authors: Karatzas, D; Rusiñol, Marçal; Antens, Coen; Ferrer Sumsi, Miquel
Abstract: The vignette effect (radial fall-off) is commonly encountered in images obtained through certain image acquisition setups and can seriously hinder automatic analysis processes. In this paper we present a fast and efficient method for dealing with vignetting in the context of object segmentation in an existing industrial inspection setup. The vignette effect is modelled here as a circular, non-linear gradient. The method estimates the gradient parameters and employs them to perform segmentation. Segmentation results on a variety of images indicate that the presented method is able to successfully tackle the vignette effect.
Fri, 17/05/2013 - 16:17
Title: 105143
Authors: Ruisánchez Capelastegui, Manuel
Editor: Stadt Jena
Fri, 17/05/2013 - 16:07
Title: An iterative algorithm for approximate median graph computation
Authors: Ferrer Sumsi, Miquel; Bunke, Horst
Abstract: Recently, the median graph has been shown to be a good choice to obtain a representative of a given set of graphs. It has been successfully applied to graph-based classification and clustering. In this paper we exploit a theoretical property of the median, which has not yet been utilized in the past, to derive a new iterative algorithm for approximate median graph computation. Experiments done using five different graph databases show that the proposed approach yields, in four out of these five datasets, better medians than two of the previous existing methods.
Fri, 17/05/2013 - 16:02
Title: On the design of a UAS flight plan monitoring and edition system
Authors: Pastor Llorens, Enric; Santamaria Barnadas, Eduard; Royo Chic, Pablo; López Rubio, Juan; Barrado Muxí, Cristina
Abstract: This paper addresses various aspects of the design and development of the pilot interface for the exploitation of highly advanced flight plan capabilities specifically designed for Unmanned Aerial Systems (UAS). This flight plan capabilities are built on top a flexible and reusable hardware/software architecture designed to facilitate the development of UAS-based applications. This flexibility is organized into an user-parameterizable UAS Service Abstraction Layer (USAL). The USAL defines a collection of standard services are their interrelations as a basic starting point for further development by UAS users. Previous research presented the advanced flying capabilities of a UAS as an extension of the Flight Control System (FCS) functionalities. Assuming a UAS with a FCS that ensures safe and stable maneuvers, we complement it with a highly capable flight plan management system. USAL flight plan is characterized by offering semantically much richer constructs than those present in most current UAS autopilots, which rely on simple lists of waypoints. This list of waypoints approach has several important limitations: it is difficult to specify complex trajectories and it does not support constructs such as conditional forks or iterations, small changes may imply having to deal with a considerable amount of waypoints and it provides no mechanism for adapting to mission time circumstances. To address these issues a new flight plan specification mechanism is proposed, that incorporates a leg concept extended to accommodate higher level constructs for specifying iterations and forks. Additional leg types, referred to as parametric leg, are also introduced. The trajectory defined by a parametric leg is automatically generated as a function of mission variables, enabling dynamic behavior and providing a very valuable means for adapting the flight to the mission evolution. Another level of adaption is provided by the conditions governing the decision-making in intersection le- - gs and the finalization of iterative legs. In this work we will focus on the development of the pilot interface for the exploitation of the introduced flight plan capabilities. The interface design requirements address an increase level of automated operation and support to react to unexpected requirements due to mission changes. Therefore, this interaction includes the available mechanisms to update the flight-plan according to UAS mission requirements, skip parts of it, react to operational contingencies, etc.