Una perspectiva sobre el modelado procedural basado en análisis estructurales

[EN] With the rise of available computing capabilities, structural analysis has recently become a key tool for building assessment usually managed by art historians, curators, and other specialist related to the study and preservation of ancient buildings. On the other hand, the flourishing field of procedural modeling has provided some exciting breakthroughs for the recreation of lost buildings and urban structures. However, there is a surprising lack of literature to enable the production of procedural-based buildings taking into account structural analysis, which has proven to be a crucial element for the recreation of faithful masonry structures. In order to perform an in-depth study of the advances in this type of analysis for cultural heritage buildings, we performed a study focused on procedural modeling that make use of structural analysis methods, especially in its application to historic masonry buildings such as churches and cathedrals. Moreover, with the aim of improving the knowledge about structural analysis of procedurally-recreated historical buildings, we have taken a geometric structure, added a set of procedural walls structured in masonry bricks, and studied its behavior in a generic, freely-available simulation tool, thus showing the feasibility of its analysis with non-specialized tools. This not only has allowed us to understand and learn how the different parameter values of a masonry structure can affect the results of the simulation, but also has proven that this kind of simulations can be easily integrated in an off-the-shelf procedural modeling tool, enabling this kind of analysis for a wide variety of historical studies, or restoration and preservation actions.[ES] Con el creciente aumento de las capacidades computacionales, el análisis estructural se ha convertido en una herramienta clave para la evaluación del estudio y conservación de edificios antiguos por parte de los historiadores del arte, curadores y otros especialistas. Por otro lado, el floreciente campo del modelado procedural ha proporcionado avances interesantes para la reconstrucción de edificios y estructuras urbanas no accesibles. Sin embargo, hay una sorprendente falta de métodos que permiten la generación deedificios procedurales, teniendo en cuenta el análisis estructural, los cuales handemostrado ser un elemento crucial para la concepciónde estructuras de mampostería. Con el fin de realizar un estudio en profundidad de los avances en este tipo de análisis para edificios del patrimonio cultural, se realizó un estudio centrado en elroldelmodelado proceduralque realizanmétodos de análisis estructural, especialmente en su aplicación a los edificios históricos de albañilería, tales como iglesias y catedrales. Por otra parte, con el objetivo de mejorar el conocimiento sobre el análisis estructural de los edificios históricos concebidosproceduralmente, hemos tomado una estructura geométrica de un atrículo, añadidoun conjunto de paredesproceduralesestructuradasen ladrillos, y estudiado su comportamiento conuna herramienta de simulación de pública disponibilidad.Con esto sedemuestra la viabilidad de su análisis con herramientas no especializadas. Esto no sólo nos ha permitido entender y aprender cómo los diferentes valores de los parámetros de una estructura de mampostería pueden afectar los resultados de la simulación, sino tambiénque este tipo de simulaciones se puede integrar fácilmente en una herramienta de modelado proceduralal alcance de todo público, lo que permite acercar este tipo de análisis a una amplia variedad de estudios históricos o acciones de restauración y conservación.This work was partially funded by the TIN2014-52211-C2-2-R project from Ministerio de Economia y Competividad, Spain.Fita, JL.; Besuievsky, G.; Patow, G. (2017). A perspective on procedural modeling based on structural analysis. Virtual Archaeology Review. 8(16):44-50. https://doi.org/10.4995/var.2017.5765SWORD445081

Understanding climate change impacts on biome and plant distributions in the Andes: Challenges and opportunities

Aim: Climate change is expected to impact mountain biodiversity by shifting species ranges and the biomes they shape. The extent and regional variation in these impacts are still poorly understood, particularly in the highly biodiverse Andes. Regional syntheses of climate change impacts on vegetation are pivotal to identify and guide research priorities. Here we review current data, knowledge and uncertainties in past, present and future climate change impacts on vegetation in the Andes. Location: Andes. Taxon: Plants. Methods: We (i) conducted a literature review on Andean vegetation responses to past and contemporary climatic change, (ii) analysed future climate projections for different elevations and slope orientations at 19 Andean locations using an ensemble of model outputs from the Coupled Model Intercomparison Project 5, and (iii) calculated changes in the suitable climate envelope area of Andean biomes and compared these results to studies that used species distribution models. Results: Future climatic changes (2040–2070) are projected to be stronger at high-elevation areas in the tropical Andes (up to 4°C under RCP 8.5), while in the temperate Andes temperature increases are projected to be up to 2°C. Under this worst-case scenario, temperate deciduous forests and the grasslands/steppes from the Central and Southern Andes are predicted to show the greatest losses of suitable climatic space (30% and 17%–23%, respectively). The high vulnerability of these biomes contrasts with the low attention from researchers modelling Andean species distributions. Critical knowledge gaps include a lack of an Andean wide plant checklist, insufficient density of weather stations at high-elevation areas, a lack of high-resolution climatologies that accommodates the Andes' complex topography and climatic processes, insufficient data to model demographic and ecological processes, and low use of palaeo data for distribution modelling. Main conclusions: Climate change is likely to profoundly affect the extent and composition of Andean biomes. Temperate Andean biomes in particular are susceptible to substantial area contractions. There are, however, considerable challenges and uncertainties in modelling species and biome responses and a pressing need for a region-wide approach to address knowledge gaps and improve understanding and monitoring of climate change impacts in these globally important biomes.publishedVersio

Numerical study of intense cyclogenesis events in the Mediterranean basin

S'han estudiat diverses ciclogènesis mediterrànies mitjançant el model atmosfèric MM5,la inversió de vorticitat potencial per peces i la tècnica de la separació de factors. Elsresultats mostren com a agents per a una ciclogènesi intensa: anomalia a nivells alts;confrontació de masses d'aire càlides i fredes a nivells baixos, desenvolupament baroclí;processos diabàtics; el mar; efectes topogràfics; baixa tèrmica; fluxes de calor superficials i les condicions atmosfèriques de l'entorn.S'ha verificat el comportament quasi-tropical dels medicans, com a mescla de la interaciómar-aire i l'existència d'una anomalia de nivells alts, amb una evolució diferent a la delshuracans. S'ha observat l'impacte en les simulacions de medicanes d'assimilar informacióde satèl·lit i de descàrregues elèctriques. S'han desenvolupat millores o nous usos d'algunestècniques emprades: quantificació energètica de la modificació derivada de la inversióde vorticitat potencial, l'ús lagrangià de la separació de factors, modificacions a parts delMM5

Gestió banc de temps

Aquest document, correspon a la memòria del Treball de Fi de Carrera (TFC), hi trobareu tota la documentació realitzada per a l'anàlisi, implementació i el disseny d'una aplicació informàtica basada en la gestió d'un banc de temps, desenvolupat utilitzant tecnologia Java JEE5.Este documento, corresponde a la memoria del Trabajo de Fin de Carrera (TFC), en él encontraréis toda la documentación realizada para el análisis, implementación y el diseño de una aplicación informática basada en la gestión de un banco de tiempo, desarrollado utilizando tecnología Java JEE5.This final degree project paper explains the analysis, implementation and design of a software application based on the management of a Time-based currency, developed using Java technology JEE5

Temporal evolution of ancient buildings

Nowadays, the improvement in Computer Graphics has benefited fields such as Cultural Heritage, where the main efforts have focused on the digital preservation of historic buildings or urban structures. In this thesis, we have developed a technique to procedurally model ancient stone buildings combined with structural simulation and we have demonstrated its viability based on non-specialized tools designed for cultural heritage users. On the other hand, some historical events involving natural phenomena, such as earthquakes, determined the evolution of the city urban infrastructure. In this thesis, we present a low-cost tool that allows the reproduction of an earthquake on old stone buildings. Furthermore, in this thesis, we have also designed a virtual reality pipeline compatible with low-cost smart-phones that allows the recreation of historical eventsAvui dia, les millores en Gràfics per Computador ha beneficiat camps com el Patrimoni Cultural, on els esforços principals s’han centrat en la preservació digital d’edificis històrics o estructures urbanes. En aquesta tesi hem desenvolupat una tècnica per modelar de manera procedural edificis antics, combinant-la amb simulació estructural, i hem demostrat la seva viabilitat basada en eines no especialitzades dissenyades per a usuaris de patrimoni cultural. D’altra banda, alguns esdeveniments històrics relacionats amb fenòmens naturals, com terratrèmols, van determinar l’evolució urbana d’una ciutat. En aquesta tesi presentem una eina de baix cost que permet la reproducció d’un terratrèmol en edificis antics. A més a més, en aquesta tesi hem dissenyat un sistema de realitat virtual adequat i compatible amb telèfons intel·ligents de baix cost que permet la recreació d’esdeveniments històric

Projected change in characteristics of near surface temperature inversions for southeast Australia

International audienceAir pollution has significant impacts on human health. Temperature inversions, especially near surface temperature inversions, can amplify air pollution by preventing convective movements and trapping pollutants close to the ground, thus decreasing air quality and increasing health issues. This effect of temperature inversions implies that trends in their frequency, strength and duration can have important implications for air quality. In this study, we evaluate the ability of three reanalysis-driven high-resolution regional climate model (RCM) simulations to represent near surface inversions at 9 sounding sites in southeast Australia. Then we use outputs of 12 historical and future RCM simulations (each with three time periods: 1990-2009, 2020-2039, and 2060-2079) from the NSW/ACT (New South Wales/Australian Capital Territory) Regional Climate Modelling (NARCliM) project to investigate changes in near surface temperature inversions. The results show that there is a substantial increase in the strength of near surface temperature inversions over southeast Australia which suggests that future inversions may intensify poor air quality events. Near surface inversions and their future changes have clear seasonal and diurnal variations. The largest differences between simulations are associated with the driving GCMs, suggesting that the large-scale circulation plays a dominant role in near surface inversion strengths

Precipitation bias correction of very high resolution regional climate models

Regional climate models are prone to biases in precipitation that are problematic for use in impact models such as hydrology models. A large number of methods have already been proposed aimed at correcting various moments of the rainfall distribution. They all require that the model produce the same or a higher number of rain days than the observational data sets, which are usually gridded data sets. Models have traditionally met this condition because their spatial resolution was coarser than the observational grids. But recent climate simulations use higher resolution and the models are likely to systematically produce fewer rain days than the gridded observations.In this study, model outputs from a simulation at 2 km resolution are compared with gridded and in situ observational data sets to determine whether the new scenario calls for revised methodologies. The gridded observations are found to be inadequate to correct the high-resolution model at daily timescales, because they are subjected to too frequent low intensity precipitation due to spatial averaging. A histogram equalisation bias correction method was adapted to the use of station, alleviating the problems associated with relative low-resolution observational grids. The wet-day frequency condition might not be satisfied for extremely dry biases, but the proposed approach substantially increases the applicability of bias correction to high-resolution models. The method is efficient at bias correcting both seasonal and daily characteristic of precipitation, providing more accurate information that is crucial for impact assessment studies

The first multi-model ensemble of regional climate simulations at kilometer-scale resolution, Part I: Evaluation of precipitation

Here we present the first multi-model ensemble of climate simulations at kilometer-scale horizontal resolution over a decade long period. A total of 22 simulations, performed by 21 European research groups are analyzed. Six different regional climate models (RCMs) are represented in the ensemble. The simulations are compared against available high-resolution precipitation observations and coarse resolution (12 km) RCMs with parameterized convection. The model simulations and observations are compared with respect to mean precipitation, precipitation intensity and frequency, and heavy precipitation on daily and hourly timescales in different seasons.The results show that kilometer-scale models produce more realistic representation of precipitation than the coarse resolution RCMs. The most significant improvements are found for heavy precipitation and precipitation frequency on both daily and hourly time scales in the summer season. In general, kilometer-scale models tend to produce more intense precipitation and reduced wet-hour frequency compared to coarse resolution models. Although differences between the model simulations at the kilometer-scale and observations exist, it is evident that they are superior to the coarse-resolution RCMs in the simulation of precipitation in the present-day climate, and thus offer a promising way forward for investigations of climate and climate change at local to regional scales.</p