Desenvolupament i implentació numèrica del criteri de Hoek i Brown en un codi d'elements finits per aplicacions en geotècnia. Aplicació a un cas real d'excavació subterrània

El treball consisteix en el desenvolupament, en llenguatge Fortran, d'un algoritme numèric elastoplàstic corresponen a la versió generalitzada (2002) del criteri de trencament de Hoek i Brown; validar-lo com a llei constitutiva; implementar-lo en un codi d'elements finits (PlaxisV8) i modelar un cas real d'excavació (Túnel de Bracons

AN ORDINARY UNDERSTANDING OF HUMAN BEINGS

In this article I elucidate the term ‘human being’ by specifyingconcepts associated to it with intention of  emphasizing the primacy of one concept in particular. This is Wittgenstein’s concept of  an ordinaryhuman being as it is used in the Philosophical Investigations (2009). It is arguedthatthis notion islogically primitive,that is to say,a basic elementinour conceptualrepertoirethat can serveusasa preliminarysourceforanalyzingdiverseaspectsof this individual. The idea is to outlinehere a conceptual framework wherein this individual can be studied

Evidence for a developing gap in a 10 Myr old protoplanetary disk

We have developed a self-consistent model of the disk around the nearby 10 Myr old star TW Hya which matches the observed spectral energy distribution and 7mm images of the disk. The model requires a significant dust size evolution and a partially-evacuated inner disk region, as predicted by theories of planet formation. The outer disk, which extends to at least 140 AU in radius, is very optically thick at IR wavelengths and quite massive ~0.06 Msun for the relatively advanced age of this T Tauri star. This implies long viscous and dust evolution timescales, although dust must have grown to sizes of order ~1cm to explain the sub-mm and mm spectral slopes. In contrast, the negligible near-infrared excess emission of this system requires that the disk be optically thin inside ~4 AU.This inner region cannot be completely evacuated; we need ~0.5 lunar mass of ~1 micron particles remaining to produce the observed 10 micron silicate emission. Our model requires a distinct transition in disk properties at ~4 AU, separating the inner and outer disk. The inner edge of the optically-thick outer disk must be heated almost frontally by the star to account for the excess flux at mid-IR wavelengths. We speculate that this truncation of the outer disk may be the signpost of a developing gap due to the effects of a growing protoplanet; the gap is still presumably evolving because material still resides in it, as indicated by the silicate emission, the molecular hydrogen emission, and by the continued accretion onto the central star (albeit at a much lower rate than typical of younger T Tauri stars). TW Hya thus may become the Rosetta stone for our understanding of the evolution and dissipation of protoplanetary disks.Comment: 23 pages including 5 figures, Accepted by AP

High-cadence, High-resolution Spectroscopic Observations of Herbig Stars HD 98922 and V1295 Aquila

Recent observational work has indicated that mechanisms for accretion and outflow in Herbig Ae/Be star-disk systems may differ from magnetospheric accretion (MA) as it is thought to occur in T Tauri star-disk systems. In this work, we assess the temporal evolution of spectral lines probing accretion and mass loss in Herbig Ae/Be systems and test for consistency with the MA paradigm. For two Herbig Ae/Be stars, HD 98922 (B9e) and V1295 Aql (A2e), we have gathered multi-epoch (~years) and high-cadence (~minutes) high-resolution optical spectra to probe a wide range of kinematic processes. Employing a line equivalent width evolution correlation metric introduced here, we identify species co-evolving (indicative of common line origin) via novel visualization. We interferometrically constrain often problematically degenerate parameters, inclination and inner disk radius, allowing us to focus on the structure of the wind, magnetosphere, and inner gaseous disk in radiative transfer models. Over all timescales sampled, the strongest variability occurs within the blueshifted absorption components of the Balmer series lines; the strength of variability increases with the cadence of the observations. Finally, high-resolution spectra allow us to probe substructure within the Balmer series' blueshifted absorption components: we observe static, low-velocity features and time-evolving features at higher velocities. Overall, we find the observed line morphologies and variability are inconsistent with a scaled-up T Tauri MA scenario. We suggest that as magnetic field structure and strength change dramatically with increasing stellar mass from T Tauri to Herbig Ae/Be stars, so too may accretion and outflow processes.Comment: 34 pages, 52 figures, published in the Ap

Risk Maps of Lassa Fever in West Africa

Previous studies on the eco-epidemiology of Lassa fever in Guinea, West Africa, have shown that the reservoir is two to three times more infected by Lassa virus in the rainy season than in the dry season. None of the intrinsic variables of the murine population, such as abundance or reproduction, was able to explain this seasonal variation in prevalence. We therefore here investigate the importance of extrinsic environmental variables, partly influenced by the idea that in the case of nephropathia epidemica in Europe contamination of the environment, and therefore survival of the pathogen outside the host, appears to be an important factor in this disease's epidemiology. We therefore made an extensive review of the literature, gathering information about the geographical location of sites where Lassa fever has been certainly identified. Environmental data for these sites (rainfall, temperature, vegetation and altitude) were gathered from a variety of sources, both satellites and ground-based meteorological stations. Several statistical treatments were applied to produce Lassa ‘risk maps’. These maps all indicate a strong influence of rainfall, and a lesser influence of temperature in defining high risk areas. The area of greatest risk is located between Guinea and Cameroon

Despliegue automático de infraestructura en la nube para el procesado de imágenes

Hoy en día la electricidad llega hasta los lugares más remotos del mundo, para ello son necesarios cientos de miles de postes eléctricos. Estos postes eléctricos permanecen a la intemperie 365 días al año, con lo que deben recibir un mantenimiento de forma periódica. Al tratarse de estructuras de grandes envergaduras tener que ir revisándolos de uno en uno es un proceso poco eficiente, ya que además se deben recorrer grandes distancias. En este caso el cliente es la empresa encargada del mantenimiento de los postes eléctricos de Pamplona, que quiere una mejora en el rendimiento del diagnóstico de los postes. Para solucionar este problema, se propone utilizar drones para la inspección de los postes eléctricos. Mediante un dron se puede fotografiar un poste en cuestión de minutos para ser analizado más tarde mediante inteligencia artificial. Una vez tomadas las fotos se procesan mediante inteligencia artificial usando redes neuronales para identificar las fotos en las que aparece un poste eléctrico. El procesado se realizará en la nube evitando que los operarios necesiten una infraestructura. Una vez procesadas, los operarios encargados de la revisión de los postes podrán acceder a un repositorio en la nube donde estarán las imágenes procesadas y podrán utilizarlas para evaluar los postes. El procesado de imágenes se hará en AWS (Amazon Web Services), para gestionar la carga y rendimiento del servicio encargado de la detección de imágenes se utilizará Kubernetes, mediante Amazon EKS (Elastic Kubernetes Service). Mientras que las imágenes se almacenarán en Amazon S3 (Simple Storage Service). El objetivo es definir la configuración necesaria para poder desplegar la infraestructura necesaria en AWS de forma automática, creando un entorno para el correcto procesado de las imágenes, utilizando infraestructura como código automatizando el aprovisionamiento de la infraestructura.Graduado o Graduada en Ingeniería Informática por la Universidad Pública de NavarraInformatika Ingeniaritzako Graduatua Nafarroako Unibertsitate Publikoa

A Spatially Resolved Inner Hole in the Disk around GM Aurigae

We present 0.3 arcsec resolution observations of the disk around GM Aurigae with the Submillimeter Array (SMA) at a wavelength of 860 um and with the Plateau de Bure Interferometer at a wavelength of 1.3 mm. These observations probe the distribution of disk material on spatial scales commensurate with the size of the inner hole predicted by models of the spectral energy distribution. The data clearly indicate a sharp decrease in millimeter optical depth at the disk center, consistent with a deficit of material at distances less than ~20 AU from the star. We refine the accretion disk model of Calvet et al. (2005) based on the unresolved spectral energy distribution (SED) and demonstrate that it reproduces well the spatially resolved millimeter continuum data at both available wavelengths. We also present complementary SMA observations of CO J=3-2 and J=2-1 emission from the disk at 2" resolution. The observed CO morphology is consistent with the continuum model prediction, with two significant deviations: (1) the emission displays a larger CO J=3-2/J=2-1 line ratio than predicted, which may indicate additional heating of gas in the upper disk layers; and (2) the position angle of the kinematic rotation pattern differs by 11 +/- 2 degrees from that measured at smaller scales from the dust continuum, which may indicate the presence of a warp. We note that photoevaporation, grain growth, and binarity are unlikely mechanisms for inducing the observed sharp decrease in opacity or surface density at the disk center. The inner hole plausibly results from the dynamical influence of a planet on the disk material. Warping induced by a planet could also potentially explain the difference in position angle between the continuum and CO data sets.Comment: 12 pages, 6 figures, accepted for publication in Ap