Publications

Displaying 826 - 850 of 1227

Publication	Date
Lower bounds for non-trivial travelling wave solutions of equations of KdV type Authors: Gustavo Ponce,Luis Vega,Carlos E. Kenig We prove that if a solution of an equation of KdV type is bounded above by a traveling wave with an amplitude that decays faster than a given linear exponential then it must be zero. We assume no restrictions neither on the size nor in the direction of the speed of the traveling wave. IOP Publishing	2012-04-02
A novel grouping harmony search algorithm for the multiple-type access node location problem Authors: Itziar Landa-Torres,Jose A. Portilla-Figueras,Sancho Salcedo-Sanz,Sergio Gil-Lopez,J. Del Ser In this paper we present a novel grouping harmony search algorithm for the Access Node Location Problem (ANLP) with different types of concentrators. The ANLP is a NP-hard problem where a set of distributed terminals, with distinct rate demands, must be assigned to a variable number of… Elsevier BV	2012-04-01
Toward Understanding EDAs Based on Bayesian Networks Through a Quantitative Analysis Authors: Alexander Mendiburu,Carlos Echegoyen,R. Santana,Jose A. Lozano The successful application of estimation of distribution algorithms (EDAs) to solve different kinds of problems has reinforced their candidature as promising black-box optimization tools. However, their internal behavior is still not completely understood and therefore it is necessary to work in… Institute of Electrical and Electronics Engineers (IEEE)	2012-04-01
Multiscale Simulations of the Antimicrobial Peptide Maculatin 1.1: Water Permeation through Disordered Aggregates Authors: Elena Akhmatskaya,Elena Akhmatskaya,Mark S.P. Sansom,Daniel L. Parton The antimicrobial peptide maculatin 1.1 (M1.1) is an amphipathic α-helix that permeabilizes lipid bilayers. In coarse-grained molecular dynamics (CG MD) simulations, M1.1 has previously been shown to form membrane-spanning aggregates in DPPC bilayers. In this study, a simple multiscale methodology… American Chemical Society (ACS)	2012-03-09
Exploiting domain information for Word Sense Disambiguation of medical documents Authors: Aitor Soroa,Eneko Agirre,Mark Stevenson Current techniques for knowledge-based Word Sense Disambiguation (WSD) of ambiguous biomedical terms rely on relations in the Unified Medical Language System Metathesaurus but do not take into account the domain of the target documents. The authors' goal is to improve these methods by using… Oxford University Press (OUP)	2012-03-01
The cost of continuity: A study of the performance of isogeometric finite elements using direct solvers Authors: Victor M. Calo,Maciej Paszyński,Nathan Collier,David Pardo,Lisandro Dalcin We study the performance of direct solvers on linear systems of equations resulting from isogeometric analysis. The problem of choice is the canonical Laplace equation in three dimensions. From this study we conclude that for a fixed number of unknowns and polynomial degree of approximation, a… Elsevier BV	2012-03-01
Centralized and distributed spectrum channel assignment in cognitive wireless networks: A Harmony Search approach Authors: Del Ser, J.,Matinmikko, Marja,Gil-López, S.,Mustonen, Miia This paper gravitates on the spectrum channel allocation problem where each compounding node of a cognitive radio network is assigned a frequency channel for transmission over a given outgoing link, based on optimizing an overall network performance metric dependant on the level of interference… Elsevier BV	2012-02-01
Existence of maximizers for Sobolev–Strichartz inequalities Authors: FANELLI, Luca,Luis Vega,Nicola Visciglia 10 pages Elsevier BV	2012-02-01
Assessing the long-term variability of Venus winds at cloud level from VIRTIS–Venus Express Authors: Agustín Sánchez-Lavega,Ricardo Hueso,Javier Peralta Abstract The Venus Express (VEX) mission has been in orbit to Venus for more than 4 years now. The Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) instrument onboard VEX observes Venus in two channels (visible and infrared) obtaining spectra and multi-wavelength images of the planet… Elsevier BV	2012-02-01
Morphology of the cloud tops as observed by the Venus Express Monitoring Camera Authors: Ralf Jaumann,Sanjay S. Limaye,David Crisp,Nikolay Ignatiev,H. U. Keller,Richard Moissl,Klaus-Dieter Matz,Agustín Sánchez-Lavega,Miguel Almeida,Thomas Roatsch,Jonas Hesemann,Dmitrij V. Titov,Larry W. Esposito,Wojciech J. Markiewicz,Frank Scholten,Stubbe F… Abstract Since the discovery of ultraviolet markings on Venus, their observations have been a powerful tool to study the morphology, motions and dynamical state at the cloud top level. Here we present the results of investigation of the cloud top morphology performed by the Venus Monitoring… Elsevier BV	2012-02-01
*Dynamic modeling of the morphology of latex particles with in situ* formation of graft copolymer** Authors: Akhmatskaya, E.,Asua, J.M. AbstractModification of the polymer–polymer interfacial tension is a way to tailor‐make particle morphology of waterborne polymer–polymer hybrids. This allows achieving a broader spectrum of application properties and maximizing the synergy of the positive properties of both polymers, avoiding… Wiley	2012-01-12
Microsatellites in immune-relevant regions and their associations with Maedi-Visna and ovine pulmonary adenocarcinoma viral diseases Authors: Ramón A. Juste,E. Minguijón,Amaia Larruskain,Begoña M. Jugo,Inmaculada Arostegui,Bernardino Moreno Maedi-Visna (MV) and ovine pulmonary adenocarcinoma (OPA) are two retroviral diseases occurring worldwide that affect adult sheep. Differences in incidence, which may be related to sheep-rearing and housing choices, as well as to genetics, and disease progression have been reported for both… Elsevier BV	2012-01-01
Petri Nets for Detecting a 3D Deadlock Problem in Hp-adaptive Finite Element Simulations Authors: Paszyńska, Anna,Paszyński, Maciej,Szymczak, Arkadiusz,Pardo, David Abstract The papers describes a Petri net model for mesh adaptation in 3D self-adaptive hp Finite Element Method ( hp- FEM) simulations. The method is applied to a model 3D problem consisting of the simulation of direct current (DC) measurements in a borehole environment with a deviated steel-… Elsevier BV	2012-01-01
Headwater reservoirs weaken terrestrial‐aquatic linkage by slowing leaf‐litter processing in downstream regulated reaches Authors: Mendoza-Lera, Clara,Larrañaga, Aitor,Pérez, Javier,Descals, Enric,Martínez, Antonio,Moya, Oscar,Arostegui, I.,Pozo, Jesús AbstractLeaf litter breakdown is a key process, providing matter and energy to communities inhabiting many headwater streams that flow through forests. This detrital pathway is affected by many human landscape transformations; but it is little known about the impact of small headwater reservoirs on… Wiley	2012-01-01
A survey on direct solvers for Galerkin methods Authors: Julen Alvarez,Nathan Collier,David Pardo,David Pardo,Maciej Paszyński,Lisandro Dalcin,Victor M. Calo In this paper we describe the history, performance, and design concepts of direct solvers for algebraic systems resulting from Galerkin discretizations of partial differential equations. Popular direct solver implementations of Gaussian elimination (also known as LU factorization) are introduced… Springer Science and Business Media LLC	2012-01-01
The 2009–2010 fade of Jupiter’s South Equatorial Belt: Vertical cloud structure models and zonal winds from visible imaging Authors: Jose Félix Rojas,Agustín Sánchez-Lavega,Santiago Pérez-Hoyos,J. F. Sanz-Requena,N. Barrado-Izagirre Abstract The South Equatorial Belt (SEB) of Jupiter is known to alternate its appearance at visible wavelengths from a classical belt-like band most of the time to a short-lived zone-like aspect which is called a “fade” of the belt, hereafter SEBF. The albedo change of the SEB is due to a change… Elsevier BV	2012-01-01
hp-HGS strategy for inverse 3D DC resistivity logging measurement simulations Authors: Gajda-Zaǵorska, Ewa,Paszýnski, Maciej,Schaefer, Robert,Pardo, David,Calo, Victor In this paper we present a twin adaptive strategy hp-HGS for solving inverse problems related to 3D DC borehole resistivity measurement simulations. The term “simulation of measurements” is widely used by the geophysical community. A quantity of interest, voltage, is measured at a receiver… Elsevier BV	2012-01-01
Concurrent and Distributed Projection through Local Interference for Wireless Sensor Networks Authors: Javier Del Ser,Pedro M. Crespo,Baltasar Beferull,Xabier Insausti In this paper we use a gossip algorithm to obtain the projection of the observed signal into a subspace of lower dimension. Gossip algorithms allow distributed, fast and efficient computations on a Wireless Sensor Network and they can be properly modified to evaluate the sought projection. By… Springer Berlin Heidelberg	2012-01-01
3D hp-Adaptive Finite Element Simulations of a Magic-T Electromagnetic Waveguide Structure Authors: Sergio Llorente-Romano,David Pardo,David Pardo,Gomez-Revuelto,Luis E. Garcia-Castillo This paper employs a 3D hp self-adaptive grid-refinement finite element strategy for the solution of a particular electromagnetic waveguide structure known as Magic-T. This structure is utilized as a power divider/combiner in communication systems as well as in other applications. It often… Elsevier BV	2012-01-01
A Note on the Wiener Filter for Vector Random Processes Authors: Adam Podhorski,Jesús Gutiérrez-Gutiérrez,Javier Del Ser,Inaki Iglesias In the present paper we compute the geometric minimum mean square error for the vector linear estimation problem. We do this by proving that the vector linear estimator that minimizes the mean square error (MSE) also minimizes the geometric MSE. Springer Berlin Heidelberg	2012-01-01
On Round-off Error for Adaptive Finite Element Methods Authors: Maciej Paszyński,Nathan Collier,David Pardo,David Pardo,Lisandro Dalcin,Julen Álvarez-Aramberri,Victor M. Calo Abstract Round-off error analysis has been historically studied by analyzing the condition number of the associated matrix. By controlling the size of the condition number, it is possible to guarantee a prescribed round-off error tolerance. However, the opposite is not true, since it is possible… Elsevier BV	2012-01-01
Social Acceptance and Usage Experiences from a Mobile Location-Aware Service Environment Authors: Klein, B.,Perez, J.,Guggenmos, C.,Pihlajamaa, Olli,Heino, Immo,Del Ser, J. MUGGES is a European research project with the goal of evaluating peer-to-peer service concepts based on GNSS systems for mobile phones. MUGGES provides an infrastructure to create, publish, provide and consume mobile micro-services directly from mobile devices. As part of the project four… Springer Berlin Heidelberg	2012-01-01
PATHS – Exploring Digital Cultural Heritage Spaces Authors: Samuel Fernando,Aitor Soroa,Kate Fernie,Runar Bergheim,Konstantinos Chandrinos,Eneko Agirre,Nikolaos Aletras,Mark Stevenson,Paula Goodale,Mark M. Hall,Jillian R. Griffiths,Andrea de Polo,Paul Clough,Oier Lopez de Lacalle Large amounts of digital cultural heritage (CH) information have become available over the past years, requiring more powerful exploration systems than just a search box. The PATHS system aims to provide an environment in which users can successfully explore a large, unknown collection through two… Springer Berlin Heidelberg	2012-01-01
Leaf-litter decomposition in headwater streams: a comparison of the process among four climatic regions Authors: Pozo, Jesús,Casas, Jesús,Menéndez, Margarita,Mollá, Salvador,Arostegui, Inmaculada,Basaguren, Ana,Casado, Carmen,Descals, Enrique,García Avilés, Javier,González, José M.,Larrañaga, Aitor,López, Enrique,Lusi, Miriam,Moya, Óscar,Pérez, Javier,Riera, Tecla,… The main purpose of our work was to elucidate factors responsible for the geographical differences in leaf-litter decomposition rates in Spanish oligotrophic headwater streams. Decomposition experiments with alder (Alnus glutinosa) leaf litter were carried out in 22 headwater streams in 4 different… University of Chicago Press	2011-12-01
The IRYSS-COPD appropriateness study: objectives, methodology, and description of the prospective cohort Authors: Quintana López, José María,Esteban, Cristóbal,Barrio Beraza, Irantzu,García Gutiérrez, Susana,González, Nerea,Arostegui Madariaga, Inmaculada,Lafuente Guerrero, Iratxe,Baré Mañas, Marisa,Blasco, Juan Antonio,Vidal, Silvia,IRYSS-COPD Group Patients with chronic obstructive pulmonary disease (COPD) often experience exacerbations of the disease that require hospitalization. Current guidelines offer little guidance for identifying patients whose clinical situation is appropriate for admission to the hospital, and properly developed and… Springer Science and Business Media LLC	2011-11-24