Now showing items 1-20 of 51

    • 3D pore analysis of sedimentary rocks 

      Vergés Garcia, Eduard; Tost Pardell, Daniela; Ayala Vallespí, M. Dolors; Ramos Guerrero, Emilio; Grau Carrión, Sergi (2010)
      External research report
      Open Access
      A 3D representation of the internal structure and fabric of sedimentary rocks is of paramount interest to evaluate their structural parameters such as porosity, pore-size distribution and permeability. The classical ...
    • 3D reconstruction and quantification of porous structures 

      Vergés Garcia, Eduard; Ayala Vallespí, M. Dolors; Grau Carrión, Sergi; Tost Pardell, Daniela (2008)
      Article
      Restricted access - publisher's policy
      In this paper, we describe the methodology that we have designed to quantify the pores distribution in bone implants and the empirical results that we have obtained with BioCAD designed scaffolds, microCT and confocal ...
    • A Complete solid model for surface rendering 

      Rodríguez Rojas, Jorge Ernesto; Ayala Vallespí, M. Dolors; Aguilera, Antonio (2003-02)
      External research report
      Open Access
      The Extreme Vertices Model (EVM) has been presented as a concise and complete model for representing orthogonal pseudo-polyhedra (OPP) in the solid modeling field. This model exploits the simplicity of its domain ...
    • A connected-component-labeling-based approach to virtual porosimetry 

      Rodríguez, Jorge Ernesto; Cruz Matías, Irving Alberto; Vergés Garcia, Eduard; Ayala Vallespí, M. Dolors (2011)
      Article
      Restricted access - publisher's policy
      Analyzing the pore-size distribution of porous materials, made up of an aggregation of interconnected pores, is a demanding task. Mercury intrusion porosimetry (MIP) is a physical method that intrudes mercury into a sample ...
    • A new lossless orthogonal simplification method for 3D objects based on bounding structures 

      Cruz Matías, Irving Alberto; Ayala Vallespí, M. Dolors (2014-07)
      Article
      Restricted access - publisher's policy
      This paper presents a new approach to simplify 3D binary images and general orthogonal pseudo-polyhedra (OPP). The method is incremental and produces a level-of-detail sequence of OPP, where any object of this sequence ...
    • An improved boundary extraction algorithm using a plane-sweep technique 

      Ayala Vallespí, M. Dolors; Vergara, Enric (2006-06)
      External research report
      Open Access
      Extracting the boundary of a 3D or a 2D image is a fundamental operation in several image processing related fields. In other fields as NC-data generation, obtaining the cutting areas of sculptured surfaces can be performed ...
    • Automatic generation of multiresolution boundary representations 

      Andújar Gran, Carlos Antonio; Ayala Vallespí, M. Dolors; Brunet Crosa, Pere; Joan Arinyo, Robert; Solé Bosquet, Jaume (1996-01)
      External research report
      Open Access
      The paper focuses on automatic simplification algorithms for the generation of a multiresolution family of solid models from an initial boundary representation of a polyhedral solid. An algorithm for general polyhedra ...
    • Bio-CAD analysis of porosity bioimplants 

      Vergés Garcia, Eduard; Ayala Vallespí, M. Dolors; Grau Carrión, Sergi; Tost Pardell, Daniela (2008)
      Conference report
      Restricted access - publisher's policy
      In this work we present two methods to compute the porosity from a μCT image. One is the virtual simulation of a porosimeter and the other is a sphere-based heuristic approach. Both methods obtain a graph representing the ...
    • Compact union of disjoint boxes: An efficient decomposition model for binary volumes 

      Cruz Matías, Irving; Ayala Vallespí, M. Dolors (2017)
      Article
      Open Access
      This paper presents in detail the CompactUnion of Disjoint Boxes (CUDB), a decomposition modelfor binary volumes that has been recently but brieflyintroduced. This model is an improved version of aprevious model called ...
    • Converting orthogonal polyhedra from extreme vertices model to B-Rep and to alternating sum of volumes 

      Ayala Vallespí, M. Dolors; Aguilera, A. (2000-11-07)
      External research report
      Open Access
      In recent published papers we presented the Extreme Vertices Model (EVM), a concise and complete model for representing orthogonal polyhedra and pseudo-polyhedra (OPP). This model exploits the simplicity of its domain ...
    • CUDB: An improved decomposition model for orthogonal pseudo-polyhedra 

      Cruz Matías, Irving; Ayala Vallespí, M. Dolors (2011)
      External research report
      Open Access
      We present a new decomposition model for Orthogonal Pseudo-Polyhedra (OPP): the Compact Union of Disjoint Boxes. This model is an improved version of the Ordered Union of Disjoint Boxes model. Our model has many desirable ...
    • Desarrollo de una aplicación CAE para el diseño de circuitos de ventilación 

      Ayala Vallespí, M. Dolors; Pla García, Núria; Soto Riera, Antoni; Vigo Anglada, Marc; Vila Marta, Sebastià (1999-07)
      External research report
      Open Access
      En este trabajo se presenta una aplicacion CAE para el diseno de circuitos de ventilacion. En ella se han desarrollado aspectos de diseno del modelo, de la interaccion con el usuario y de simulacion del comportamiento ...
    • Determination of shape and sphericity of silicon quantum dots imaged by EFTEM-tomography 

      Ayala Vallespí, M. Dolors; Hiller, Daniel; Gutsch, Sebastian; López Vidrier, Julián; Zacharias, Margit; Estradé Albiol, Sònia; Peiró Martínez, Francesca; Cruz-Matías, Irving (2017-11-06)
      Article
      Open Access
      The shape of size-controlled silicon nanocrystals (Si NCs) embedded in SiO2 is investigated by tomographic energy-filtered transmission electron microscopy (EFTEM). The sphericity of the quantum dots is determined by ...
    • Domain extension for the extreme vertices model (EVM) and set membership classification 

      Aguilera, Antonio; Ayala Vallespí, M. Dolors (1997-12)
      External research report
      Open Access
      In a previous work, orthogonal polyhedra were proposed as geometric bounds in Constructice Solid Geometry (CSG). CSG primitives were approximated by orthogonal polyhedra, and the orthogonal bound of the object was obtained ...
    • Efficient algorithms for boundary extraction of 2D and 3D orthogonal pseudomanifolds 

      Vigo Anglada, Marc; Pla García, Núria; Ayala Vallespí, M. Dolors; Martínez Bayona, Jonàs (2011)
      External research report
      Open Access
      In this paper we present algorithms to extract the boundary representation of orthogonal polygons and polyhedra, either manifold or pseudomanifold. The algorithms we develop reconstruct not only the polygons of the boundaries ...
    • Efficient algorithms for boundary extraction of 2D and 3D orthogonal pseudomanifolds 

      Vigo Anglada, Marc; Pla García, Núria; Ayala Vallespí, M. Dolors; Martínez Bayona, Jonás (2012)
      Article
      Restricted access - publisher's policy
      In this paper we present algorithms to extract the boundary representation of orthogonal polygons and polyhedra, either manifold or pseudomanifold. The algorithms we develop reconstruct not only the polygons of the boundaries ...
    • Efficient computation of 3D skeletons by extreme vertex encoding 

      Rodríguez Rojas, Jorge Ernesto; Thomas, Federico; Ayala Vallespí, M. Dolors; Ros Giralt, Lluís (2003)
      Article
      Open Access
      Many skeletonisation algorithms for discrete volumes have been proposed. Despite its simplicity, the one given here still has many theoretically favorable properties. Actually, it provides a connected surface skeleton that ...
    • Fast connected component labeling algorithm: a non voxel-based approach 

      Ayala Vallespí, M. Dolors; Rodríguez, J; Aguilera, A (2002-03)
      External research report
      Open Access
      This paper presents a new approach to achieve connected component labeling on both binary images and volumes by using the Extreme Vertices Model (EVM), a representation model for orthogonal polyhedra, applied to digital ...
    • Fast neighborhood operations for images and volume datasets 

      Rodríguez Rojas, Jorge Ernesto; Ayala Vallespí, M. Dolors (2003-02)
      External research report
      Open Access
      This paper presents a new approach to carry out erosion, dilation and connected component labeling. We use the Extreme Vertices Model (EVM), an orthogonal polyhedra representation, to describe binary images and ...
    • Faster ASV decomposition for orthogonal polyhedra using the Extreme Vertices Model (EVM) 

      Aguilera Ramírez, Fernando Antonio; Ayala Vallespí, M. Dolors (2000-01)
      External research report
      Open Access
      The alternating sum of volumes (ASV) decomposition is a widely used technique for converting a B-Rep into a CSG model. The obtained CSG tree has convex primitives at its leaf nodes, while the contents of its internal ...