Publications

Displaying 1126 - 1150 of 1351

Publication	Date
DYNAMIC SEARCH SPACE TRANSFORMATIONS FOR SOFTWARE TEST DATA GENERATION Authors: Ramón Sagarna,Jose A. Lozano Among the tasks in software testing, test data generation is particularly difficult and costly. In recent years, several approaches that use metaheuristic search techniques to automatically obtain the test inputs have been proposed. Although work in this field is very active, little attention has… Wiley	2008-01-21
Software Metrics Mining to Predict the Performance of Estimation of Distribution Algorithms in Test Data Generation Authors: Ramón Sagarna,Jose A. Lozano Springer Berlin Heidelberg	2008-01-01
Determination of Riser Tensioner Properties From Full-Scale Data Authors: Gupta H.,Nava V.,Banon H.,Gkaras V.,Spanos P. Tensioners are used for supporting various kinds of production and drilling risers on offshore platforms. All permanent production facilities (such as TLP’s and Spar’s) have employed tensioners to support their dry tree production risers. The key design parameters for the tensioners design are… ASMEDC	2008-01-01
PML Enhanced with a Self-Adaptive Goal-Oriented $hp$-Finite Element Method: Simulation of Through-Casing Borehole Resistivity Measurements Authors: Pardo, D.,Demkowicz, L.,Torres-Verdin, C.,Michler, Christian We describe the application of a perfectly matched layer (PML) combined with a self-adaptive goal-oriented $hp$-finite element (FE) method to the simulation of borehole resistivity measurements. The adaptive refinements and fast convergence of the self-adaptive $hp$-FE method enhance the… Society for Industrial & Applied Mathematics (SIAM)	2008-01-01
Distribution of the O₂ infrared nightglow observed with VIRTIS on board Venus Express Authors: Gérard, Jean-Claude,Saglam, Adem,Piccioni, Giuseppe,Drossart, Pierre,Cox, Cedric,Erard, Stéphane,Hueso, R.,Sánchez-Lavega, Agustín We present characteristics of the statistical horizontal distribution of the O2 infrared nightglow over most of the southern hemisphere observed with the VIRTIS instrument over a period spanning nearly 11 months of low solar activity. We show that the distribution is inhomogeneous with the regions… American Geophysical Union (AGU)	2008-01-01
Simulations of 3D DC borehole resistivity measurements with a goal-oriented hp finite-element method. Part II: through-casing resistivity instruments Authors: Carlos Torres-Verdín,Maciej Paszyński,David Pardo We simulate direct current (DC) borehole resistivity measurements acquired in steel-cased deviated wells for the assessment of rock formation properties. The assumed data acquisition configuration considers one current (emitter) and three voltage (collector) electrodes that are utilized to measure… Springer Science and Business Media LLC	2007-12-06
Energy Concentration and Sommerfeld Condition for Helmholtz Equation with Variable Index at Infinity Authors: Luis Vega,Benoît Perthame,Benoît Perthame We consider the Helmholtz equation with a variable index of refraction $n(x)$, which is not necessarily constant at infinity but can have an angular dependency like $n(x)\to n\_\infty(x/\|x \|)$ as $\|x \|\to \infty$. Under some appropriate assumptions on this convergence and on $n\_\infty$ we prove… Springer Science and Business Media LLC	2007-11-26
Hardy-type estimates for Dirac operators Authors: Dolbeault, Jean,Duoandikoetxea, Javier,Esteban, Maria J.,Vega, Luis We prove some Hardy type inequalities related to the Dirac operator by elementary methods, for a large class of potentials, which even includes measure valued potentials. Optimality is achieved by the Coulomb potential. When potentials are smooth enough, our estimates provide some spectral… Societe Mathematique de France	2007-11-01
A two-dimensional self-adaptive hp finite element method for the characterization of waveguide discontinuities. Part I: Energy-norm based automatic hp-adaptivity Authors: Luis E. Garcia-Castillo,Leszek Demkowicz,Ignacio Gomez-Revuelto,David Pardo Abstract The accurate analysis and characterization of waveguide discontinuities is an important issue in microwave engineering. In some cases, the discontinuities are an unavoidable result of mechanical or electric transitions which effects have to be minimized; in other cases, the… Elsevier BV	2007-11-01
Numerical models of Saturn's long-lived anticyclones Authors: García-Melendo, Enrique,Sánchez-Lavega, Agustín,Hueso, Ricardo Abstract New measurements of the dynamical properties of the long-lived Saturn's anticyclonic vortex known as “Brown Spot” (BS), discovered during the Voyager 1 and 2 flybys in 1980–1981 at latitude 43.1° N, and model simulations using the EPIC code, have allowed us to constrain the vertical wind… Elsevier BV	2007-11-01
A two-dimensional self-adaptive hp finite element method for the characterization of waveguide discontinuities. Part II: Goal-oriented hp-adaptivity Authors: Carlos Torres-Verdín,David Pardo,Leszek Demkowicz,Luis E. Garcia-Castillo Abstract This is the second part of the work on the analysis of different types of rectangular waveguide discontinuities by using a fully automatic hp -adaptive finite element method. In this paper, we describe a fully automatic goal-oriented hp -adaptive Finite Element (FE) strategy. The… Elsevier BV	2007-11-01
Combining variable neighborhood search and estimation of distribution algorithms in the protein side chain placement problem Authors: Santana, Roberto,Larrañaga Múgica, Pedro María,Lozano, Jose Antonio The aim of this work is to introduce several proposals for combining two metaheuristics: variable neighborhood search (VNS) and estimation of distribution algorithms (EDAs). Although each of these metaheuristics has been previously hybridized in several ways, this paper constitutes the first… Springer Science and Business Media LLC	2007-10-23
The perspective: a panorama of the Solar System Authors: Agustín Sánchez-Lavega Cambridge University Press (CUP)	2007-10-18
Diversity Gain Analysis of a Novel Dual-Frequency Multiple Access Relay Transmission Scheme Authors: J. Del Ser,Pedro M. Crespo,B.H. Khalaj,Jesús Gutiérrez-Gutiérrez In this paper, we will present diversity gain analysis of a novel channel assignment scheme at the relay for the case in which two non-cooperative independent users communicate with their destination through a single relay and by using only two frequency channels. The analysis of two main relay… IEEE	2007-10-01
A reanalysis of Venus winds at two cloud levels from Galileo SSI images Authors: Ricardo Hueso,Agustín Sánchez-Lavega,Javier Peralta Abstract The global circulation of the Venus atmosphere is characterized at cloud level by a zonal super rotation studied over the years with data from a battery of spacecrafts: orbiters, balloons and probes. Among them, the Galileo spacecraft monitored the Venus atmosphere in a flyby in February… Elsevier BV	2007-10-01
On Combining Distributed Joint Source-Channel-Network Coding and Turbo Equalization in Multiple Access Relay Networks Authors: Pedro M. Crespo,B.H. Khalaj,Jesús Gutiérrez-Gutiérrez,J. Del Ser We consider a multiple access relay channel where two sources S1 and S2 send their data to a common destination node aided by a shared relay node. In this paper we extend previous work on this topic by assuming that the output of both information sources are correlated with memory. Furthermore, we… IEEE	2007-10-01
Comparative analysis of the parameters affecting AED rhythm analysis algorithm applied to pediatric and adult Ventricular Tachycardia Authors: S. Ruiz de Gauna,Elisabete Aramendi,Unai Irusta,Jesus Ruiz In this study pediatric and adult Ventricular Tachycardia (VT) are used to test the efficiency of an AED analysis algorithm. Statistical assessment of the four significant parameters that define the shock-noshock classification algorithm has been performed. The following parameters are considered:… IEEE	2007-09-01
Sequential VT/VF discrimination algorithm based on wave mode sample entropy for adult and pediatric patients Authors: Elisabete Aramendi,S.R. de Gauna,Unai Irusta,Jesus Ruiz The two fatal ventricular arrhythmias, Ventricular Fibrillation (VF) and Ventricular Tachycardia (VT), are better treated using different electrical therapies: a lower energy cardioversion for VT and a defibrillation shock for VF. Automated External Defibrillators (AED), whose use for children is… IEEE	2007-09-01
Validation of a screening questionnaire for hip and knee osteoarthritis in old people Authors: Quintana López, José María,Arostegui Madariaga, Inmaculada,Escobar, Antonio,Lafuente Guerrero, Iratxe,Arenaza Merino, Juan Carlos,García, Isidoro,Aguirre, Urko To develop a sensitive and specific screening tool for knee and hip osteoarthritis in the general population of elderly people.The Knee and Hip OsteoArthritis Screening Questionnaire (KHOA-SQ) was developed based on previous studies and observed data and sent to 11,002 people aged 60 to 90 years,… Springer Science and Business Media LLC	2007-08-23
A self-adaptive goal-oriented hp-finite element method with electromagnetic applications. Part II: Electrodynamics Authors: Leszek Demkowicz,Carlos Torres-Verdín,Maciej Paszyński,David Pardo Abstract We present the formulation, implementation, and applications of a self-adaptive, goal-oriented, hp-Finite Element (FE) Method for Electromagnetic (EM) problems. The algorithm delivers (without any user interaction) a sequence of optimal hp-grids. This sequence of grids minimizes the… Elsevier BV	2007-08-01
A parallel framework for loopy belief propagation Authors: Alexander Mendiburu,Endika Bengoetxea,Jose A. Lozano,Roberto Santana There are many innovative proposals introduced in the literature under the evolutionary computation field, from which estimation of distribution algorithms (EDAs) is one of them. Their main characteristic is the use of probabilistic models to represent the (in) dependencies between the variables of… ACM	2007-07-07
Source Controlled Modulation Scheme for Sources with Memory Authors: Pedro M. Crespo,E. Loyo,C.J. Mitchell,J. Del Ser Given an AWGN channel, we look at the problem of designing a source controlled binary antipodal signaling system for transmitting blocks of binary symbols generated either by a Markov chain source (MC) or by a hidden Markov model source (HMM). The goal is to minimize the average SNR required for… IEEE	2007-06-01
Cloud brightness distribution and turbulence in Venus using Galileo violet images Authors: Agustín Sánchez-Lavega,Javier Peralta,Ricardo Hueso Venus cloud covered atmosphere offers a well-suited framework to study the coupling between the atmospheric dynamics and the structure of the cloud field. Violet images obtained during the Galileo flyby from 12 to 17 February 1990 have been analyzed to retrieve the zonal power spectra of the cloud… Elsevier BV	2007-06-01
Feasibility study for 2D frequency-dependent electromagnetic sensing through casing Authors: Leszek Demkowicz,Carlos Torres-Verdín,David Pardo We perform a numerical-sensitivity study of various physical phenomena of interest for borehole resistivity logging applications in steel-cased wells. Specifically, we analyze the sensitivity of through-casing measurements for detecting water invasion, shale-laminated sands, and electrical… Society of Exploration Geophysicists	2007-05-01
Improving the performance of perfectly matched layers by means of hp‐adaptivity Authors: Christian Michler,Jason Kurtz,David Pardo,Leszek Demkowicz AbstractWe improve the performance of the Perfectly Matched Layer (PML) by using an automatic hp‐adaptive discretization. By means of hp‐adaptivity, we obtain a sequence of discrete solutions that converges exponentially to the continuum solution. Asymptotically, we thus recover the property of the… Wiley	2007-04-26