Hardware and software improvements of volume splatting

This paper proposes different hardware-based acceleration of the three classical splatting strategies: emph{composite-every-sample}, emph{object-space sheet-buffer} and emph{image-space sheet-buffer}.Preprin

Skeletonless porosimeter simulation

We introduce a new approach to simulate a virtual mercury intrusion porosimetry (MIP) using neither skeleton computing nor seed-growing methods. Most of the existing methods to determine local pore sizes in a porous medium require to compute the skeleton of the pore space. However, the skeleton computation is a very time consuming process. Instead, our approach uses a particular spatial enumeration encoding of the porous media, a set of disjoint boxes, and an algorithm able to determine the set of boxes invaded by the mercury at each iteration without any need of a previous skeleton computation. The algorithm detects all the pores which must be lled for a given mercury intrusion pressure, which is related to a diameter by the Washburn equation. The presented method is able to detect narrow throats and one-dimensional transitions between pores in order to prevent incorrect full uid invasion of the whole sample. The particular encoding used in this work is a new compact version of an existing model, the Ordered Union of Disjoint Boxes (OUDB). Finally, the pore size distribution of the porous medium and the corresponding pore graph can be obtained from the analyzed sample.Postprint (published version

Design of graphical interfaces for biomedical applications

The visualization in biomedical applications includes diverse objects in a wide rank of scale, from molecules and cells to physiological, biomechanical and biophysical parts of the body, their anatomy and properties. The design of intuitive graphical interfaces that allow users to fastly select parameters is a key factor for the usability of visualization applications. Nevertheless, this task is often relegated to a secondary plane in software development. This largely contributes to the fast lapsing of these applications. In this article, we described the design of the library BioMedIGU, a tool conceived to make easier the development of biomedical applications interfaces and reinforces their reusability. An example of its use for the visualization platform HipoVis it is also shown.Postprint (published version

3D pore analysis of sedimentary rocks

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 experimental technique to evaluate the pore space volume and pore size distribution is the Mercury Intrusion Porosimetry (MIP). Computer-based methods use 3D imaging technologies such as Computer Tomography (CT) scanned images to construct and evaluate a 3D virtual representation of the internal pore distribution. In this work, based on a three samples set of sandstone, we apply two numerical (computer-based) methods in order to reconstruct and analyse the internal pore network, and compare it with the results obtained by MIP analysis. The first numerical method performs a virtual simulation of MIP. The second one obtains a graph of pores using a sphere-filling based approach. For all methods, we compute the global porosity and the pore-size distribution. Moreover, with the numerical methods, we obtain the total porosity and a graph representing the pore space that can be visualized with 3D illustration techniques.Postprint (published version

Jardins per a la salut

Facultat de Farmàcia, Universitat de Barcelona. Ensenyament: Grau de Farmàcia. Assignatura: Botànica farmacèutica. Curs: 2014-2015. Coordinadors: Joan Simon, Cèsar Blanché i Maria Bosch.Els materials que aquí es presenten són el recull de les fitxes botàniques de 128 espècies presents en el Jardí Ferran Soldevila de l’Edifici Històric de la UB. Els treballs han estat realitzats manera individual per part dels estudiants dels grups M-3 i T-1 de l’assignatura Botànica Farmacèutica durant els mesos de febrer a maig del curs 2014-15 com a resultat final del Projecte d’Innovació Docent «Jardins per a la salut: aprenentatge servei a Botànica farmacèutica» (codi 2014PID-UB/054). Tots els treballs s’han dut a terme a través de la plataforma de GoogleDocs i han estat tutoritzats pels professors de l’assignatura. L’objectiu principal de l’activitat ha estat fomentar l’aprenentatge autònom i col·laboratiu en Botànica farmacèutica. També s’ha pretès motivar els estudiants a través del retorn de part del seu esforç a la societat a través d’una experiència d’Aprenentatge-Servei, deixant disponible finalment el treball dels estudiants per a poder ser consultable a través d’una Web pública amb la possibilitat de poder-ho fer in-situ en el propi jardí mitjançant codis QR amb un smartphone

Improved virtual porosimeter

Recently, the term BioCAD has appeared to refer to the modeling of biological processes. This work focuses on the analysis of structural properties such as porosity of bioimplants for bone reconstruction. Specifically, we present a method that, using 3D microCT images, simulates the behavior of a porosimeter, i.e. an instrument to measure the porous structure of a sample. After segmentation, we perform an intrusion simulation using the distance map, topological skeleton and connected component labeling of the volume’s porous region, which produces a result comparable to the real porosimeter experiment. This initial method has been modified to take advantage of the properties of the Extreme Vertices Model (EVM), which is a very compact form of volume representation with simple base operations. The output is the same yet the computation is faster.Peer ReviewedPostprint (published version

Improved virtual porosimeter

Recently, the term BioCAD has appeared to refer to the modeling of biological processes. This work focuses on the analysis of structural properties such as porosity of bioimplants for bone reconstruction. Specifically, we present a method that, using 3D microCT images, simulates the behavior of a porosimeter, i.e. an instrument to measure the porous structure of a sample. After segmentation, we perform an intrusion simulation using the distance map, topological skeleton and connected component labeling of the volume’s porous region, which produces a result comparable to the real porosimeter experiment. This initial method has been modified to take advantage of the properties of the Extreme Vertices Model (EVM), which is a very compact form of volume representation with simple base operations. The output is the same yet the computation is faster.Peer Reviewe

Improved virtual porosimeter

Recently, the term BioCAD has appeared to refer to the modeling of biological processes. This work focuses on the analysis of structural properties such as porosity of bioimplants for bone reconstruction. Specifically, we present a method that, using 3D microCT images, simulates the behavior of a porosimeter, i.e. an instrument to measure the porous structure of a sample. After segmentation, we perform an intrusion simulation using the distance map, topological skeleton and connected component labeling of the volume’s porous region, which produces a result comparable to the real porosimeter experiment. This initial method has been modified to take advantage of the properties of the Extreme Vertices Model (EVM), which is a very compact form of volume representation with simple base operations. The output is the same yet the computation is faster.Peer Reviewe

Design of graphical interfaces for biomedical applications

The visualization in biomedical applications includes diverse objects in a wide rank of scale, from molecules and cells to physiological, biomechanical and biophysical parts of the body, their anatomy and properties. The design of intuitive graphical interfaces that allow users to fastly select parameters is a key factor for the usability of visualization applications. Nevertheless, this task is often relegated to a secondary plane in software development. This largely contributes to the fast lapsing of these applications. In this article, we described the design of the library BioMedIGU, a tool conceived to make easier the development of biomedical applications interfaces and reinforces their reusability. An example of its use for the visualization platform HipoVis it is also shown

Hardware and software improvements of volume splatting

This paper proposes different hardware-based acceleration of the three classical splatting strategies: emph{composite-every-sample}, emph{object-space sheet-buffer} and emph{image-space sheet-buffer}