Mesh projection between parametric surfaces

  This paper presents a new algorithm to map a given mesh over a source surface onto a target surface. This projection is determined by means of a least-squares approximation of a transformation defined between the loops of boundary nodes of the cap surfaces in the parametric spaces. Once the new mesh is obtained on the parametric space of the target surface, it is mapped to the target surface according to its parameterization. Therefore, in contrast with the usual techniques, the developed algorithm does not require solving any root finding problem to ensure that the projected nodes are on the target surface. Finally, this projection algorithm is extended to three-dimensional cases and included in a sweep meshing tool in order to generate the inner layers of elements in the physical space

A new least-squares approximation of affine mappings for sweep algorithms

This paper presents a new algorithm to generate hexahedral meshes in extrusion geometries. Several algorithms have been devised to generate hexahedral meshes by projecting the cap surfaces along a sweep path. In all of these algorithms the crucial step is the placement of the inner layer of nodes. That is, the projection of the source surface mesh along the sweep path. From the computational point of view, sweep methods based on a least-squares approximation of an affine mapping are the fastest alternative to compute these projections. Several functionals have been introduced to perform the least-squares approximation. However, for very simple and typical geometrical configurations they may generate low-quality projected meshes. For instance, they may induce skewness and flattening effects on the projected discretizations. In addition, for these configurations the minimization of these functionals may lead to a set of normal equations with singular system matrix. In this work we analyze previously defined functionals. Based on this analysis we propose a new functional and show that its minimization overcomes these drawbacks. Finally, we present several examples to assess the properties of the proposed functional

Application of a cellular automata model to the metropolitan area of Barcelona

Cellular Automata (CA) models are among the most popular models for simulating land use change/growth in urban areas around the world and have experienced a significant development over the last twenty years. These models have their origins on the efforts of devising mathematical rules for biological systems and for evolution developed by mathematicians von Neumann and Stanislaw Ulam in the 1940s. Two main features made CA interesting for urban studies, to which they were introduced by Waldo Tobler in the early 1970s. First, their intrinsic spatiality, which is suitable for the simulation of a variety of geographic phenomena. Second, the possibility of simulating complex patterns of, for example, land use starting from a simple conceptual framework that includes the definition of a cell space, a neighborhood, and a finite set of transition rules applied to a finite set of cell states. These models have been developed for different urban contexts and are mainly based on the use of regular cells derived from remote sensing imagery. This is a simplification in the representation of urban areas: on the one hand, regular cells do not represent common urban form and, on the other hand, they do not held information of any type other than land use, obtained from automatic classification. These issues suggested the consideration of irregular cells linked to reliable information, that is, census blocks. Census blocks are drawn considering the form of urban areas and they are the most reliable source of data on a wide variety of subjects, being a natural choice for the design of CA cells. We present in this paper an application of a CA model to simulate urban change in the Metropolitan Area of Barcelona, in a prospective analysis of 20 years. The model uses irregular cells designed considering census blocks. We describe the main features of the model and the calibration process, as well as the simulation results. We also discuss some new features that are the core of our current research on CA.Peer ReviewedPostprint (published version

Identificación de la estructura urbana del Algarve (Portugal) mediante el valor de interacción

Muchos estudios tienen como referencia la ciudad, analizándola y comparándola desde diferentes perspectivas y para multitud de finalidades. La división administrativa, propia de cada territorio, sirve generalmente de unidad de partida, sin cuestionar el ámbito que abarcan las ciudades reales, su área de influencia, su estructura interna... lo cual dificulta la comparación entre realidades urbanas de distintos territorios, acentuándose cuando se trata de diferentes países. Aunque la metodología desarrollada a partir del Valor de Interacción permite delimitar la estructura urbana mediante las relaciones funcionales que se establecen entre el mercado de trabajo y el de residencia, la necesidad de obtener la escala local o urbana exige disponer de la matriz de movilidad obligada por trabajo para unidades administrativas pequeñas (el ámbito local). En el caso de Portugal los municipios, concelhos, son muy extensos y aunque existe una división inframunicipal, la freguesia, el Censo sólo registra los desplazamientos entre freguesia de residencia y concelho de trabajo. Así, este trabajo propone identificar el sistema urbano del distrito de Faro de Portugal a partir de las freguesias, estimando para ello los flujos originados por la movilidad obligada por trabajo entre estas entidades inframunicipales.Peer Reviewe

Interstitial pulmonary fibrosis with and without associated collagen vascular diseases: results of a two year follow up

Background: Interstitial pulmonary fibrosis is a disease with a highly variable clinical course. To ascertain if an inadequate selection of patients might explain part of this variability, two different groups of patients with interstitial pulmonary fibrosis, those with the 'lone' form of the disease (LIPF) and those with associated collagen vascular disorders (AIPF), were studied separately. Methods: Twenty consecutive patients (nine with LIPF and 11 with AIPF) were included. Their clinical and radiographic findings and results of pulmonary function tests, gallium-67 lung scanning, and cellular analysis of bronchoalveolar lavage fluid were compared at diagnosis. Moreover, the evolution of LIPF and AIPF was contrasted after a follow up of two years, both groups having received a similar treatment regimen of corticosteroids. Results: At enrollment, patients with LIPF and AIPF were of similar age, and had similar symptoms and derangement of lung function, but patients with LIPF presented with finger clubbing, more obvious radiographic abnormalities, and a greater percentage of eosinophils in bronchoalveolar lavage fluid. Two years later, patients with LIPF had significantly decreased FVC, FEV1, TLC, TLCO, and PaO2. By contrast, lung function remained unaltered in patients with AIPF. Similarly, when the percentage change from entry to the study was compared, patients with LIPF showed a significant decrease in FVC, FEV1, and PaO2. Conclusions: Unlike the patients with AIPF, those with LIPF showed a deterioration in lung function and developed further restrictive impairment and poorer gas exchange. This has implications in their clinical management

Identificación de la estructura urbana del Algarve (Portugal) mediante el valor de interacción

Muchos estudios tienen como referencia la ciudad, analizándola y comparándola desde diferentes perspectivas y para multitud de finalidades. La división administrativa, propia de cada territorio, sirve generalmente de unidad de partida, sin cuestionar el ámbito que abarcan las ciudades reales, su área de influencia, su estructura interna... lo cual dificulta la comparación entre realidades urbanas de distintos territorios, acentuándose cuando se trata de diferentes países. Aunque la metodología desarrollada a partir del Valor de Interacción permite delimitar la estructura urbana mediante las relaciones funcionales que se establecen entre el mercado de trabajo y el de residencia, la necesidad de obtener la escala local o urbana exige disponer de la matriz de movilidad obligada por trabajo para unidades administrativas pequeñas (el ámbito local). En el caso de Portugal los municipios, concelhos, son muy extensos y aunque existe una división inframunicipal, la freguesia, el Censo sólo registra los desplazamientos entre freguesia de residencia y concelho de trabajo. Así, este trabajo propone identificar el sistema urbano del distrito de Faro de Portugal a partir de las freguesias, estimando para ello los flujos originados por la movilidad obligada por trabajo entre estas entidades inframunicipales.Peer Reviewe

Energy efficient object detection for automotive applications with YOLOv3 and approximate hardware

Deep neural networks are the dominant models for perception tasks in the automotive domain, but their high computational complexity makes it difficult to execute them in real time with an acceptable power consumption on general-purpose devices. For this reason, the design of custom ASIC devices for real-time energy-efficient neural network deployment is a hot topic in academia and industry. Low-precision integer arithmetic and approximate computing are two popular optimizations often contemplated for saving hardware resources and power consumption. In this work, we evaluate two approximate computing circuits using different integer precisions in order to study the trade-offs that these techniques offer in terms of energy efficiency and degradation of the neural network outputs. In particular, we apply the approximations to the YOLOv3 object detection network, a popular model for critical applications in the automotive domain. By combining approximate arithmetic circuits with low precision we are able to reduce the power consumption of a MAD unit by over 50% compared to using only quantization.Peer ReviewedPostprint (author's final draft

El paper dels sistemes de gestió en el desenvolupament de competències transversals en els estudiants

S’ha treballat la formació competencial dels estudiants mitjançant la realització d’activitats relacionades amb la implementació de sistemes de gestió (qualitat, medi ambient i seguretat). A l’assignatura “Qualitat i Prevenció” (Grau Química), els alumnes han fet auditories de medi ambient i seguretat als laboratoris de pràctiques de la Facultat de Química. Els alumnes de l’assignatura “Direcció d’operacions en el sector químic” (màster Enginyeria Química) han treballat la implementació del sistemes de gestió mitjançant un joc de rol. Finalment, a “Anàlisi i estimació del risc” (màster Enginyeria Química) s’ha treballat una part concreta del sistema de gestió de la seguretat mitjançant l’anàlisi de risc d’una pràctica de laboratori. Els estudiants han treballat competències relacionades amb l’ètica, capacitat d’expressió oral i escrita, capacitat de diàleg, capacitat de lideratge, gestió de la qualitat, el medi ambient i la seguretat. Els resultats de les actuacions han posat de manifest mancances i problemes als laboratoris i als sistemes de gestió, l’anàlisi del quals ha de permetre millorar la qualitat de les pràctiques i dels ensenyaments. Finalment, les enquestes fetes a alguns dels grups implicats han reflectit un alt grau de satisfacció amb la feina feta i la manera de fer-la

Analysis and prediction of COVID-19 for EU-EFTA-UK and other countries

The present report aims to provide a comprehensive picture of the pandemic situation of COVID-19 in the EU countries, and to be able to foresee the situation in the next coming days. We employ an empirical model, verified with the evolution of the number of confirmed cases in previous countries where the epidemic is close to conclude, including all provinces of China. The model does not pretend to interpret the causes of the evolution of the cases but to permit the evaluation of the quality of control measures made in each state and a short-term prediction of trends. Note, however, that the effects of the measures’ control that start on a given day are not observed until approximately 7-10 days later. The model and predictions are based on two parameters that are daily fitted to available data: a: the velocity at which spreading specific rate slows down; the higher the value, the better the control. K: the final number of expected cumulated cases, which cannot be evaluated at the initial stages because growth is still exponential. We show an individual report with 8 graphs and a table with the short-term predictions for different countries and regions. We are adjusting the model to countries and regions with at least 4 days with more than 100 confirmed cases and a current load over 200 cases. The predicted period of a country depends on the number of datapoints over this 100 cases threshold, and is of 5 days for those that have reported more than 100 cumulated cases for 10 consecutive days or more. For short-term predictions, we assign higher weight to last 3 points in the fittings, so that changes are rapidly captured by the model. The whole methodology employed in the inform is explained in the last pages of this document. In addition to the individual reports, the reader will find an initial dashboard with a brief analysis of the situation in EU-EFTA-UK countries, some summary figures and tables as well as long-term predictions for some of them, when possible. These long-term predictions are evaluated without different weights to datapoints. We also discuss a specific issue every day.These reports are funded by the European Commission (DG CONNECT, LC-01485746) PJC and MC received funding from “la Caixa” Foundation (ID 100010434), under agreement LCF/PR/GN17/50300003; CP, DL, SA, MC, received funding from Ministerio de Ciencia, Innovación y Universidades and FEDER, with the project PGC2018-095456-B-I00Postprint (published version