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• Un caso práctico de meta-evaluación docente: el manual de evaluación de la Universidad Politécnica de Cataluña

  E. Montilla, R. Vega, G. Amblàs, E. Martínez, L. Campeny, G. Bugeda, S. Roca

  Aula Abierta (2012). Vol. 40 (2), pp. 11-24

  
  

  Abstract

  La Universidad Politécnica de Cataluña ha sido pionera en la introducción de un modelo de evaluación docente plenamente adaptado a las exigencias del Espacio Europeo de Enseñanza Superior. Además, su sistema de evaluación de la actividad docente del profesorado ha sido homologa- do por la AQU y ANECA. Dicho modelo de evaluación docente se basa en las más recientes directrices europeas y tiene como fundamento diversos indicadores indirectos. Este modelo se ha empleado para evaluar la docencia del profesorado en cinco convocatorias. Durante este periodo de tiempo se ha acumulado una información valiosísima que permite obtener datos agregados no sólo de la calidad de los docentes sino, también, de diversas características inherentes al proceso de evaluación, así como de la bondad de los indicadores empleados. En este artículo se presentan es- tos datos y se muestra un conjunto de datos agregados que permiten estimar la bondad y fiabilidad del proceso de evaluación, así como su aceptación por el profesorado evaluado.

  Abstract
  La Universidad Politécnica de Cataluña ha sido pionera en la introducción de un modelo de evaluación docente plenamente adaptado a las exigencias [...]

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• Double-shock control bump design optimization using hybridized evolutionary algorithms

  D. Lee, L. Gonzalez, J. Periaux, G. Bugeda

  Proceedings of the Institution of Mechanical Engineers. Part G, journal of aerospace engineering (2011). Vol. 225 (10), pp. 1175-1192

  
  

  Abstract

  This study investigates the application of two advanced optimization methods for solving active flow control (AFC) device shape design problem and compares their optimization efficiency in terms of computational cost and design quality. The first optimization method uses hierarchical asynchronous parallel multi-objective evolutionary algorithm and the second uses hybridized evolutionary algorithm with Nash-Game strategies (Hybrid-Game). Both optimization methods are based on a canonical evolution strategy and incorporate the concepts of parallel computing and asynchronous evaluation. One type of AFC device named shock control bump (SCB) is considered and applied to a natural laminar flow (NLF) aerofoil. The concept of SCB is used to decelerate supersonic flow on suction/pressure side of transonic aerofoil that leads to a delay of shock occurrence. Such active flow technique reduces total drag at transonic speeds which is of special interest to commercial aircraft. Numerical results show that the Hybrid-Game helps an EA to accelerate optimization process. From the practical point of view, applying a SCB on the suction and pressure sides significantly reduces transonic total drag and improves lift-to-drag (L/D) value when compared to the baseline design.

  Abstract
  This study investigates the application of two advanced optimization methods for solving active flow control (AFC) device shape design problem and compares their optimization [...]

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• Estrategias e indicadores para la evaluación de la docencia en el marco del EEES

  E. Garcia-Berro, F. Dapia, G. Amblas, G. Bugeda, S. Roca

  Revista de investigación en educación (2009). Vol. 6, pp. 142-152

  
  

  Abstract

  En este artículo se describen las estrategias que ha emprendido la Universidad Politécnica de Cataluña (UPC) para implantar las nuevas titulaciones de Ingeniería adaptadas al Espacio Europeo de Enseñanza Superior (EEES). Estas estrategias pueden ser de utilidad para otras universidades. Partiendo de un análisis detallado del contexto general de la Universidad española y de la UPC en particular, se muestra el sistema de planificación estratégica de nuestra institución. Asimismo se describe en detalle el sistema de indicadores estadísticos que se usa para medir el rendimiento de centros y departamentos en el referido marco de planificación estratégica. Por último, también se detallan las acciones que se han emprendido para evaluar la actividad docente del profesorado.

  Abstract
  En este artículo se describen las estrategias que ha emprendido la Universidad Politécnica de Cataluña (UPC) para implantar las nuevas titulaciones de [...]

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• A new adaptive remeshing scheme based on the sensitivity analysis of the SPR point wise error estimation

  G. Bugeda

  Comput. Methods Appl. Mech. Engrg., (2006). Vol. 195 (4-6), pp. 462-478

  
  

  Abstract

  This paper presents a formulation for the obtainment of the sensitivity analysis of a point wise error estimator with respect to the nodal coordinates using the adjoint state method. The proposed point wise error estimator is based on the SPR method. The numerical accuracy of the presented sensitivity analysis has been tested by perturbing a mesh. The capability of the presented sensitivity analysis for the detection of pollution error has also been tested. A new adaptive remeshing strategy based on the sensitivity analysis of the point wise error estimation has been developed and tested. This strategy produces very cheap meshes for the accurate evaluation of stresses at specific points.

  Abstract
  This paper presents a formulation for the obtainment of the sensitivity analysis of a point wise error estimator with respect to the nodal coordinates using the adjoint state [...]

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• A comparison between new adaptive remeshing strategies based on point wise stress error estimation and energy norm error estimation

  G. Bugeda

  Commun. Numer. Meth. Engng (2002). Vol. 18 (7), 469-482

  
  

  Abstract

  Traditionally, the most commonly used mesh adaptive strategies for linear elastic problems are based on the use of an energy norm for the measurement of the error, and a mesh refinement strategy based on the equal distribution of the error between all the elements. However, little attention has been paid to the study of alternative error norms and alternative refinement strategies. This paper studies the feasibility of using alternative mesh refinement strategies based on — the use of the classical error energy norm and an optimality criterion based on the equal distribution of the density of error, — the use of alternative error norms based on measurements of the point wise error contained in the main magnitudes that control the equilibrium problem and/or the material constitutive equations such as the stresses (e.g. the Von Mises stress). The feasibility of using all the described strategies is demonstrated through the solution of a benchmark example. This example is also used for comparison between the described refinement criteria.

  Abstract
  Traditionally, the most commonly used mesh adaptive strategies for linear elastic problems are based on the use of an energy norm for the measurement of the error, and a mesh [...]

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• A C++ object-oriented programming strategy for the implementation of the finite element sensitivity analysis for a non-linear structural material model

  L. Gil, G. Bugeda

  Advances in Engineering Software (2001). Vol. 32 (12), pp. 927-935

  
  

  Abstract

  The Finite Element Method (FEM) has become the most popular numerical method for solving a wide variety of complex engineering problems. However, from the programming point of view, when a FEM program has a lot of computational capabilities it is very difficult to maintain and enlarge the program codes. Recently the object-oriented programming paradigm has become a powerful method for overcoming such difficulties. This paper contains the description of an open environment for the FEM, written in C++, with explanations about how the sensitivity analysis and the non-linear material behaviour (damage models) have been taken into accoun

  Abstract
  The Finite Element Method (FEM) has become the most popular numerical method for solving a wide variety of complex engineering problems. However, from the programming [...]

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• Shape sensitivity analysis for structural problems with non‐linear material behaviour

  G. Bugeda, L. Gil

  Int. J. Numer. Meth. Engng. (1999). Vol. 46 (9), pp. 1385-1404

  
  

  Abstract

  This paper describes some considerations around the analytical structural shape sensitivity analysis when the structural behaviour is computed using the finite element method with a non‐linear constitutive material model. Depending on the type of non‐linear behaviour two different approaches are proposed. First, a new direct (non‐incremental) formulation is proposed for material models characterized by the fact that the stresses at any time t can be expressed in terms of the strains at the same time t and, in some cases, the strains at a specific past time tu (tu<t). This is the case of elasticity (linear as well as non‐linear), perfect plasticity and damage models. Second, a more classical incremental approach is proposed for general plasticity cases. A special strategy is also proposed for material models with strain softening. The quality and reliability of the proposed approaches are assessed through their application in different examples.

  Abstract
  This paper describes some considerations around the analytical structural shape sensitivity analysis when the structural behaviour is computed using the finite element method [...]

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• A general methodology for structural shape optimization problems using automatic adaptive remeshing

  G. Bugeda, J. Oliver

  Int. J. Numer. Meth. Engng. (1993). Vol. 36 (18), pp. 3161-3185

  
  

  Abstract

  The proposed methodology is based on the use of the adaptive mesh refinement (AMR ) techniques in the context of 2D shape optimization problems analysed by the finite element method. A suitable and very general technique for the parametrization of the optimization problem, using B‐splines to define the boundary, is first presented. Then mesh generation, using the advancing frontal method, the error estimator and the mesh refinement criterion are studied in the context of shape optimization problems In particular, the analytical sensitivity analysis of the different items ruling the problem (B‐splines. finite element mesh, structural behaviour and error estimator) is studied in detail. The sensitivities of the finite element mesh and error estimator permit their projection from one design to the next one leading to an a priori knowledge of the finite element error distribution on the new design without the necessity of any additional structural analysis. With this information the mesh refinement criterion permits one to build up a finite element mesh on the new design with a specified and controlled level of error. The robustness and reliability of the proposed methodology is checked by means of several examples.

  Abstract
  The proposed methodology is based on the use of the adaptive mesh refinement (AMR ) techniques in the context of 2D shape optimization problems analysed by the finite element [...]

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• Multiscale Computational Homogenization: Review and Proposal of a New Enhanced-First-Order Method

  F. Otero, S. Oller, X. Martinez

  (2017). Notas de Modelación y Métodos Numéricos VII. Mathematical Models for Material Sciences and their Industrial Application. Editores: J. Montalvo-Urquizo, M.A. Moreles, S. Botello. Centro de Investigación en Matemáticas (CIMAT) - CIMNE. pp. 71-112. ISBN 978-84-95999-88-7.

  
  

  Abstract

  The continuous increase of computational capacity has encouraged the extensive use of multiscale techniques to simulate the material behaviour on several fields of knowledge. In solid mechanics, the multiscale approaches which consider the macro-scale deformation gradient to obtain the homogenized material behaviour from the micro-scale are called first-order computational homogenization. Following this idea, the second-order FE2 methods incorporate high-order gradients to improve the simulation accuracy. However, to capture the full advantages of these high-order framework the classical boundary value problem (BVP) at the macro-scale must be upgraded to high-order level, which complicates their numerical solution. With the purpose of obtaining the best of both methods i.e. first-order and second-order, in this work an enhanced-first-order computational homogenization is presented. The proposed approach preserves a classical BVP at the macro-scale level but taking into account the high-order gradient of the macro-scale in the micro-scale solution. The developed numerical examples show how the proposed method obtains the expected stress distribution at the micro-scale for states of structural bending loads. Nevertheless, the macro-scale results achieved are the same than the ones obtained with a first-order framework because both approaches share the same macro-scale BVP.

  Abstract
  The continuous increase of computational capacity has encouraged the extensive use of multiscale techniques to simulate the material behaviour on several fields of knowledge. [...]

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• Análisis no-lineal de materiales compuestos mediante la teoría de mezclas serie-paralelo

  X. Martinez, S. Oller, F. Rastellini

  (2014). Omnia Publisher. Capítulo 10 - p. 237-260. Aplicaciones avanzadas de los materiales compuestos en la obra civil y la edificación, ISBN: 978-84-941872-9-2

  
  

  Abstract
  Este libro presenta una panorámica del estado actual de los materiales compuestos y sus aplicaciones más relevantes en la obra civil y la edificación

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