Now showing items 28-47 of 197

    • Automatic Red-Channel underwater image restoration 

      Galdran A.; Pardo D.; Picón A.; Alvarez-Gila A. (Journal of Visual Communication and Image Representation, 2015-12-31)
      Underwater images typically exhibit color distortion and low contrast as a result of the exponential decay that light suffers as it travels. Moreover, colors associated to different wavelengths have different attenuation ...
    • BBIPED: BCAM-Baltogar Industrial Platform for Engineering Design 

      Alonso-Montes C.; Garcia I.; Ramezani A.; Remaki L. (18th International Conference on Circuits, Systems, Communications and Computers (CSCC 2014); Advances in Engineering Mechancis and Materials, Proc.the International Conference; on Industrial Engineering (INDE 2014)", 2014-12-31)
      Currently, commercial software for computational fluid dynamics offers a good set of features to deal with traditional designs. Within a competitive market industrial innovation is a key factor that must be faced by ...
    • Blisk blades manufacturing technologies analysis 

      Calleja A.; Gonzalez H.; Polvorosa R.; Gomez G.; Ayesta I.; Barton M.; de Lacalle N. (Procedia Manufacturing, 2019-06)
      The paper presents blisk blades manufactured by different manufacturing processes. In this sense, different milling trajectories are presented, and, super abrasive machining strategies and EDM technologies are also tested. ...
    • Borehole Resistivity Simulations of Oil-Water Transition Zones with a 1.5D Numerical Solver 

      Shahriari M.; Pardo D. (Computational Geosciences volume, 2020)
      When simulating borehole resistivity measurements in a reservoir, it is common to consider an oilwater contact (OWC) planar interface. However, this consideration can lead to an unrealistic model since in the presence of ...
    • A C 0 interior penalty discontinuous Galerkin Method for fourth-order total variation flow. II: Existence and uniqueness 

      Kumar R.; Hoppe R.H.W.; Bhandari C. (NMPDE:Numerical Methods For Partial Differential Equations, 2019-02-25)
      We prove the existence and uniqueness of a solution of a C0 Interior Penalty Discontinuous Galerkin (C0 IPDG) method for the numerical solution of a fourth‐order total variation flow problem that has been developed in part ...
    • A C0 interior penalty discontinuous Galerkin method for fourth‐order total variation flow I: Derivation of the method and numerical results 

      Kumar R.; Hoppe R.H.W.; Bhandari C. (NMPDE:Numerical Methods For Partial Differential Equations, 2019-02-23)
      We consider the numerical solution of a fourth‐order total variation flow problem representing surface relaxation below the roughening temperature. Based on a regularization and scaling of the nonlinear fourth‐order parabolic ...
    • Computation of slat noise sources using adaptive FEM and lighthill's analogy 

      Hoffman J.; Jansson J.; de Abreu R.V. (19th AIAA/CEAS Aeroacoustics Conference, 2013-12-31)
      This is a summary of preliminary results from simulations with the 30P30N high-lift device. We used the General Galerkin finite element method (G2), where no explicit subgrid model is used, and where the computational mesh ...
    • Computational cost estimates for parallel shared memory isogeometric multi-frontal solvers 

      Wozniak M.; Kuznik K.; Paszynski M.; Calo V.M.; Pardo D. (Computers and Mathematics with Applications, 2014-12-31)
      In this paper we present computational cost estimates for parallel shared memory isogeometric multi-frontal solvers. The estimates show that the ideal isogeometric shared memory parallel direct solver scales as $\mathcal{O}( ...
    • Computational cost of isogeometric multi-frontal solvers on parallel distributed memory machines 

      Wozniak M.; Paszynski M.; Pardo D.; Dalcin L.; Calo V.M. (Computer Methods in Applied Mechanics and Engineering, 2015-12-31)
      This paper derives theoretical estimates of the computational cost for isogeometric multi-frontal direct solver executed on parallel distributed memory machines. We show theoretically that for the $C^{p-1}$ global continuity ...
    • Computational fixed-point theory for differential delay equations with multiple time lags 

      Kiss G.; Lessard J.-P. (Journal of Differential Equations, 2012-12-31)
      We introduce a general computational fixed-point method to prove existence of periodic solutions of differential delay equations with multiple time lags. The idea of such a method is to compute numerical approximations of ...
    • Control of distributed parameter systems modelled by parabolic variational inequalities of the obstacle type 

      Kumar R.; Glowinski R.; Jansson J. (2019)
      We will investigate the numerical solution of the control problem modelled by parabolic variational inequalities. The general point of view adopted in this work has its roots in the work by R. Glowinski. The optimal control ...
    • A Deep Learning Approach to the Inversion of Borehole Resistivity Measurements 

      Shahriari M.; Pardo D.; Picon A.; Galdran A.; Del Ser J.; Torres-Verdin C. (Computational Geosciences volume, 2020-04)
      Borehole resistivity measurements are routinely employed to measure the electrical properties of rocks penetrated by a well and to quantify the hydrocarbon pore volume of a reservoir. Depending on the degree of geometrical ...
    • A Deep Neural Network as Surrogate Model for Forward Simulation of Borehole Resistivity Measurements 

      Shahriari M.; Pardo D.; Moser B. (Procedia Manufacturing, 2020-01)
      Inverse problems appear in multiple industrial applications. Solving such inverse problems require the repeated solution of the forward problem. This is the most time-consuming stage when employing inversion techniques, ...
    • Dimensionally adaptive hp-finite element simulation and inversion of 2D magnetotelluric measurements 

      Alvarez-Aramberri J.; Pardo D. (Journal of Computational Science, 2016-09-01)
      Magnetotelluric (MT) problems often contain different subdomains where the conductivity of the media depends upon one, two, or three spatial variables. Traditionally, when a MT problem incorporates a three-dimensional (3D) ...
    • Direct FEM computation of turbulent multiphase flow in 3D priting nozzle design 

      Krishnasamy E.; Jansson J. (2020)
      In this paper, we present a nozzle design of the 3D printing using FEniCS-HPC as mathematical and simulation tool. In recent years 3D printing or Additive Manufacturing (AM) has become a emerging technology and it has ...
    • Direct FEM large scale computation of turbulent multiphase flow in urban water systems and marine energy 

      Krishnasamy E.; Hoffman J.; Jansson J. (Proceesings of ECCOMAS Congress 2016 VII European Congress on Computational Methods in Applied Sciences and Engineering, 2016-11-30)
      High-Reynolds number turbulent incompressible multiphase flow represents a large class of engineering problems of key relevance to society. Here we describe our work on modeling two such problems: 1. The Consorcio de Aguas ...
    • Direct finite element simulation of turbulent flow for marine based renewable energy 

      Jansson J.; Nguyen V.D.; Moragues M.; Castanon D.; Saavedra L.; Krishnasamy E.; Goude A.; Hoffman J. (Companion paper to F. Wendt, et. al. International energy agency ocean energy systems task 10 wave energy converter modeling verification and validation. In 12th European Wave and Tidal Energy Conference, 2017., 2017)
      In this article we present a computational framework for simulation of turbulent flow in marine based renewable energy applications. In particular, we focus on floating structures and rotating turbines. This work is an ...
    • Direct solvers performance on h-adapted grids 

      Paszynski M.; Pardo D.; Calo V.M. (Computers and Mathematics with Applications, 2015-12-31)
      We analyse the performance of direct solvers when applied to a system of linear equations arising from an $h$-adapted, $C^0$ finite element space. Theoretical estimates are derived for typical $h$-refinement patterns arising ...
    • Discontinuous high-order finite-volume/finite-element method for inviscid compressible flows 

      Ramezani A.; Stipcich G.; Remaki L. (53rd AIAA Aerospace Sciences Meeting (2015), 2015-12-31)
      The discontinuous, hybrid control-volume/finite-element method merges the desirable conservative properties and intuitive physical formulation of the finite-volume technique, with the capability of local arbitrary high-order ...
    • Discrete maximum principles for nonlinear parabolic PDE systems 

      Faragó I.; Karátson J.; Korotov S. (IMA Journal of Numerical Analysis, 2012-12-31)
      Discrete maximum principles (DMPs) are established for finite element approximations of systems of nonlinear parabolic partial differential equations with mixed boundary and interface conditions. The results are based on ...