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We present galaxy-galaxy lensing measurements using a sample of low surface brightness galaxies (LSBGs) drawn from the Dark Energy Survey Year 3 (Y3) data as lenses. LSBGs are diffuse galaxies with a surface brightness dimmer than the ambient night sky. These dark-matter-dominated objects are intriguing due to potentially unusual formation channels that lead to their diffuse stellar component. Given the faintness of LSBGs, using standard observational techniques to characterize their total masses proves challenging. Weak gravitational lensing, which is less sensitive to the stellar component of galaxies, could be a promising avenue to estimate the masses of LSBGs. Our LSBG sample consists of 23,790 galaxies separated into red and blue color types at $g-i\ge 0.60$ and $g-i< 0.60$, respectively. Combined with the DES Y3 shear catalog, we measure the tangential shear around these LSBGs and find signal-to-noise ratios of 6.67 for the red sample, 2.17 for the blue sample, and 5.30 for the full sample. We use the clustering redshifts method to obtain redshift distributions for the red and blue LSBG samples. Assuming all red LSBGs are satellites, we fit a simple model to the measurements and estimate the host halo mass of these LSBGs to be $\log(M_{\rm host}/M_{\odot}) = 12.98 ^{+0.10}_{-0.11}$. We place a 95% upper bound on the subhalo mass at $\log(M_{\rm sub}/M_{\odot})

We present cosmological constraints from the sample of Type Ia supernovae (SNe Ia) discovered and measured during the full 5 yr of the Dark Energy Survey (DES) SN program. In contrast to most previous cosmological samples, in which SNe are classified based on their spectra, we classify the DES SNe using a machine learning algorithm applied to their light curves in four photometric bands. Spectroscopic redshifts are acquired from a dedicated follow-up survey of the host galaxies. After accounting for the likelihood of each SN being an SN Ia, we find 1635 DES SNe in the redshift range 0.10 < z < 1.13 that pass quality selection criteria sufficient to constrain cosmological parameters. This quintuples the number of high-quality z > 0.5 SNe compared to the previous leading compilation of Pantheon+ and results in the tightest cosmological constraints achieved by any SN data set to date. To derive cosmological constraints, we combine the DES SN data with a high-quality external low-redshift sample consisting of 194 SNe Ia spanning 0.025 < z < 0.10. Using SN data alone and including systematic uncertainties, we find Ω _M = 0.352 ± 0.017 in flat ΛCDM. SN data alone now require acceleration ( q _0 < 0 in ΛCDM) with over 5 σ confidence. We find $({{\rm{\Omega }}}_{{\rm{M}}},w)=({0.264}_{-0.096}^{+0.074},-{0.80}_{-0.16}^{+0.14})$ in flat w CDM. For flat w _0 w _a CDM, we find $({{\rm{\Omega }}}_{{\rm{M}}},{w}_{0},{w}_{a})=({0.495}_{-0.043}^{+0.033},-{0.36}_{-0.30}^{+0.36},-{8.8}_{-4.5}^{+3.7})$ , consistent with a constant equation of state to within ∼2 σ . Including Planck cosmic microwave background, Sloan Digital Sky Survey baryon acoustic oscillation, and DES 3 × 2pt data gives (Ω _M , w ) = (0.321 ± 0.007, −0.941 ± 0.026). In all cases, dark energy is consistent with a cosmological constant to within ∼2 σ . Systematic errors on cosmological parameters are subdominant compared to statistical errors; these results thus pave the way for future photometrically classified SN analyses.

We present a joint cosmic shear analysis of the Dark Energy Survey (DES Y3) and the Kilo-Degree Survey (KiDS-1000) in a collaborative effort between the two survey teams. We find consistent cosmological parameter constraints between DES Y3 and KiDS-1000 which, when combined in a joint-survey analysis, constrain the parameter $S_8 = \sigma_8 \sqrt{\Omega_{\rm m}/0.3}$ with a mean value of $0.790^{+0.018}_{-0.014}$. The mean marginal is lower than the maximum a posteriori estimate, $S_8=0.801$, owing to skewness in the marginal distribution and projection effects in the multi-dimensional parameter space. Our results are consistent with $S_8$ constraints from observations of the cosmic microwave background by Planck, with agreement at the $1.7\sigma$ level. We use a Hybrid analysis pipeline, defined from a mock survey study quantifying the impact of the different analysis choices originally adopted by each survey team. We review intrinsic alignment models, baryon feedback mitigation strategies, priors, samplers and models of the non-linear matter power spectrum. Supplementary information: you can download the chains here or create your own chains with CosmoSIS here.

Low-surface-brightness galaxies (LSBGs) are excellent probes of quenching and other environmental processes near massive galaxies. We study an extensive sample of LSBGs near massive hosts in the local universe that are distributed across a diverse range of environments. The LSBGs with surface-brightness ${\mu }_{\mathrm{eff},{g}}\gt 24.2\,\mathrm{mag}\,{\mathrm{arcsec}}^{-2}$ are drawn from the Dark Energy Survey Year 3 catalog while the hosts with masses $9.0\lt \mathrm{log}({{ \mathcal M }}_{\star }/{M}_{\odot })\lt 11.0$ comparable to the Milky Way and the Large Magellanic Cloud are selected from the z0MGS sample. We study the projected radial density profiles of LSBGs as a function of their color and surface brightness around hosts in both the rich Fornax–Eridanus cluster environment and the low-density field. We detect an overdensity with respect to the background density, out to 2.5 times the virial radius for both hosts in the cluster environment and the isolated field galaxies. When the LSBG sample is split by g − i color or surface brightness μ _eff, _g , we find the LSBGs closer to their hosts are significantly redder and brighter, like their high-surface-brightness counterparts. The LSBGs form a clear “red sequence” in both the cluster and isolated environments that is visible beyond the virial radius of the hosts. This suggests preprocessing of infalling LSBGs and a quenched backsplash population around both host samples. More so, the relative prominence of the “blue cloud” feature implies that preprocessing is ongoing near the isolated hosts compared to the cluster environment where the LSBGs are already well processed.

We present the full Hubble diagram of photometrically classified Type Ia supernovae (SNe Ia) from the Dark Energy Survey supernova program (DES-SN). DES-SN discovered more than 20,000 SN candidates and obtained spectroscopic redshifts of 7000 host galaxies. Based on the light-curve quality, we select 1635 photometrically identified SNe Ia with spectroscopic redshift 0.10 < z < 1.13, which is the largest sample of supernovae from any single survey and increases the number of known z > 0.5 supernovae by a factor of 5. In a companion paper, we present cosmological results of the DES-SN sample combined with 194 spectroscopically classified SNe Ia at low redshift as an anchor for cosmological fits. Here we present extensive modeling of this combined sample and validate the entire analysis pipeline used to derive distances. We show that the statistical and systematic uncertainties on cosmological parameters are ${\sigma }_{{{\rm{\Omega }}}_{M},\mathrm{stat}+\mathrm{sys}}^{{\rm{\Lambda }}\mathrm{CDM}}=$ 0.017 in a flat ΛCDM model, and $({\sigma }_{{{\rm{\Omega }}}_{M}},{\sigma }_{w}{)}_{\mathrm{stat}+\mathrm{sys}}^{w\mathrm{CDM}}$ = (0.082, 0.152) in a flat w CDM model. Combining the DES SN data with the highly complementary cosmic microwave background measurements by Planck Collaboration reduces by a factor of 4 uncertainties on cosmological parameters. In all cases, statistical uncertainties dominate over systematics. We show that uncertainties due to photometric classification make up less than 10% of the total systematic uncertainty budget. This result sets the stage for the next generation of SN cosmology surveys such as the Vera C. Rubin Observatory's Legacy Survey of Space and Time.

We present griz photometric light curves for the full 5 yr of the Dark Energy Survey Supernova (DES-SN) program, obtained with both forced point-spread function photometry on difference images ( DiffImg ) performed during survey operations, and scene modelling photometry (SMP) on search images processed after the survey. This release contains 31,636 DiffImg and 19,706 high-quality SMP light curves, the latter of which contain 1635 photometrically classified SNe that pass cosmology quality cuts. This sample spans the largest redshift ( z ) range ever covered by a single SN survey (0.1 < z < 1.13) and is the largest single sample from a single instrument of SNe ever used for cosmological constraints. We describe in detail the improvements made to obtain the final DES-SN photometry and provide a comparison to what was used in the 3 yr DES-SN spectroscopically confirmed Type Ia SN sample. We also include a comparative analysis of the performance of the SMP photometry with respect to the real-time DiffImg forced photometry and find that SMP photometry is more precise, more accurate, and less sensitive to the host-galaxy surface brightness anomaly. The public release of the light curves and ancillary data can be found at http://github.com/des-science/DES-SN5YR and doi:10.5281/zenodo.12720777.

Redshift measurements, primarily obtained from host galaxies, are essential for inferring cosmological parameters from type Ia supernovae (SNe Ia). Matching SNe to host galaxies using images is nontrivial, resulting in a subset of SNe with mismatched hosts and thus incorrect redshifts. We evaluate the host galaxy mismatch rate and resulting biases on cosmological parameters from simulations modeled after the Dark Energy Survey 5 Yr (DES-SN5YR) photometric sample. For both DES-SN5YR data and simulations, we employ the directional light radius method for host galaxy matching. In our SN Ia simulations, we find that 1.7% of SNe are matched to the wrong host galaxy, with redshift differences between the true and matched hosts of up to 0.6. Using our analysis pipeline, we determine the shift in the dark energy equation of state parameter (Δ w ) due to including SNe with incorrect host galaxy matches. For SN Ia–only simulations, we find Δ w = 0.0013 ± 0.0026 with constraints from the cosmic microwave background. Including core-collapse SNe and peculiar SNe Ia in the simulation, we find that Δ w ranges from 0.0009 to 0.0032, depending on the photometric classifier used. This bias is an order of magnitude smaller than the expected total uncertainty on w from the DES-SN5YR sample of ∼0.03. We conclude that the bias on w from host galaxy mismatch is much smaller than the uncertainties expected from the DES-SN5YR sample, but we encourage further studies to reduce this bias through better host-matching algorithms or selection cuts.

We report results from a systematic wide-area search for faint dwarf galaxies at heliocentric distances from 0.3 to 2 Mpc using the full 6 yr of data from the Dark Energy Survey (DES). Unlike previous searches over the DES data, this search specifically targeted a field population of faint galaxies located beyond the Milky Way virial radius. We derive our detection efficiency for faint, resolved dwarf galaxies in the Local Volume with a set of synthetic galaxies and expect our search to be complete to M _V ∼ (−7, −10) mag for galaxies at D = (0.3, 2.0) Mpc. We find no new field dwarfs in the DES footprint, but we report the discovery of one high-significance candidate dwarf galaxy at a distance of ${2.2}_{-0.12}^{+0.05}\,\mathrm{Mpc}$ , a potential satellite of the Local Volume galaxy NGC 55, separated by 47′ (physical separation as small as 30 kpc). We estimate this dwarf galaxy to have an absolute V -band magnitude of $-{8.0}_{-0.3}^{+0.5}\,\mathrm{mag}$ and an azimuthally averaged physical half-light radius of ${2.2}_{-0.4}^{+0.5}\,\mathrm{kpc}$ , making this one of the lowest surface brightness galaxies ever found with $\mu =32.3\,\mathrm{mag}\,{\mathrm{arcsec}}^{-2}$ . This is the largest, most diffuse galaxy known at this luminosity, suggesting possible tidal interactions with its host.

We address the problem of optimally identifying all kilonovae detected via gravitational-wave emission in the upcoming LIGO/Virgo/KAGRA observing run, O4, which is expected to be sensitive to a factor of ∼7 more binary neutron star (BNS) alerts than previously. Electromagnetic follow-up of all but the brightest of these new events will require >1 m telescopes, for which limited time is available. We present an optimized observing strategy for the DECam during O4. We base our study on simulations of gravitational-wave events expected for O4 and wide-prior kilonova simulations. We derive the detectabilities of events for realistic observing conditions. We optimize our strategy for confirming a kilonova while minimizing telescope time. For a wide range of kilonova parameters, corresponding to a fainter kilonova compared to GW170817/AT 2017gfo, we find that, with this optimal strategy, the discovery probability for electromagnetic counterparts with the DECam is ∼80% at the nominal BNS gravitational-wave detection limit for O4 (190 Mpc), which corresponds to an ∼30% improvement compared to the strategy adopted during the previous observing run. For more distant events (∼330 Mpc), we reach an ∼60% probability of detection, a factor of ∼2 increase. For a brighter kilonova model dominated by the blue component that reproduces the observations of GW170817/AT 2017gfo, we find that we can reach ∼90% probability of detection out to 330 Mpc, representing an increase of ∼20%, while also reducing the total telescope time required to follow up events by ∼20%.

We present a detailed chemical abundance analysis of the brightest star in the ultrafaint dwarf (UFD) galaxy candidate Cetus II from high-resolution Magellan/MIKE spectra. For this star, DES J011740.53-173053, abundances or upper limits of 18 elements from carbon to europium are derived. Its chemical abundances generally follow those of other UFD galaxy stars, with a slight enhancement of the α -elements (Mg, Si, and Ca) and low neutron-capture element (Sr, Ba, and Eu) abundances supporting the classification of Cetus II as a likely UFD. The star exhibits lower Sc, Ti, and V abundances than Milky Way (MW) halo stars with similar metallicity. This signature is consistent with yields from a supernova originating from a star with a mass of ∼11.2 M _⊙ . In addition, the star has a potassium abundance of [K/Fe] = 0.81, which is somewhat higher than the K abundances of MW halo stars with similar metallicity, a signature that is also present in a number of UFD galaxies. A comparison including globular clusters and stellar stream stars suggests that high K is a specific characteristic of some UFD galaxy stars and can thus be used to help classify objects as UFD galaxies.

We report the methods of and initial scientific inferences from the extraction of precision photometric information for the >800 trans-Neptunian objects (TNOs) discovered in the images of the Dark Energy Survey (DES). Scene-modeling photometry is used to obtain shot-noise-limited flux measures for each exposure of each TNO, with background sources subtracted. Comparison of double-source fits to the pixel data with single-source fits are used to identify and characterize two binary TNO systems. A Markov Chain Monte Carlo method samples the joint likelihood of the intrinsic colors of each source as well as the amplitude of its flux variation, given the time series of multiband flux measurements and their uncertainties. A catalog of these colors and light-curve amplitudes A is included with this publication. We show how to assign a likelihood to the distribution q ( A ) of light-curve amplitudes in any subpopulation. Using this method, we find decisive evidence (i.e., evidence ratio

We perform a search for galaxy–galaxy strong lens systems using a convolutional neural network (CNN) applied to imaging data from the first public data release of the DECam Local Volume Exploration Survey, which contains ∼520 million astronomical sources covering ∼4000 deg ^2 of the southern sky to a 5 σ point–source depth of g = 24.3, r = 23.9, i = 23.3, and z = 22.8 mag. Following the methodology of similar searches using Dark Energy Camera data, we apply color and magnitude cuts to select a catalog of ∼11 million extended astronomical sources. After scoring with our CNN, the highest-scoring 50,000 images were visually inspected and assigned a score on a scale from 0 (not a lens) to 3 (very probable lens). We present a list of 581 strong lens candidates, 562 of which are previously unreported. We categorize our candidates using their human-assigned scores, resulting in 55 Grade A candidates, 149 Grade B candidates, and 377 Grade C candidates. We additionally highlight eight potential quadruply lensed quasars from this sample. Due to the location of our search footprint in the northern Galactic cap ( b > 10 deg) and southern celestial hemisphere (decl. < 0 deg), our candidate list has little overlap with other existing ground-based searches. Where our search footprint does overlap with other searches, we find a significant number of high-quality candidates that were previously unidentified, indicating a degree of orthogonality in our methodology. We report properties of our candidates including apparent magnitude and Einstein radius estimated from the image separation.

We combine photometry of Eris from a 6 month campaign on the Palomar 60 inch telescope in 2015, a 1 month Hubble Space Telescope WFC3 campaign in 2018, and Dark Energy Survey data spanning 2013–2018 to determine a light curve of definitive period 15.771 ± 0.008 days (1 σ formal uncertainties), with nearly sinusoidal shape and peak-to-peak flux variation of 3%. This is consistent at part-per-thousand precision with the P = 15.785 90 ± 0.00005 day sidereal period of Dysnomia’s orbit around Eris, strengthening the recent detection of synchronous rotation of Eris by Szakáts et al. with independent data. Photometry from Gaia are consistent with the same light curve. We detect a slope of 0.05 ± 0.01 mag per degree of Eris’s brightness with respect to illumination phase averaged across g , V , and r bands, intermediate between Pluto’s and Charon’s values. Variations of 0.3 mag are detected in Dysnomia’s brightness, plausibly consistent with a double-peaked light curve at the synchronous period. The synchronous rotation of Eris is consistent with simple tidal models initiated with a giant-impact origin of the binary, but is difficult to reconcile with gravitational capture of Dysnomia by Eris. The high albedo contrast between Eris and Dysnomia remains unexplained in the giant-impact scenario.

Wavelength-dependent atmospheric effects impact photometric supernova flux measurements for ground-based observations. We present corrections on supernova flux measurements from the Dark Energy Survey Supernova Program’s 5YR sample (DES-SN5YR) for differential chromatic refraction (DCR) and wavelength-dependent seeing, and we show their impact on the cosmological parameters w and Ω _m . We use g − i colors of Type Ia supernovae to quantify astrometric offsets caused by DCR and simulate point-spread functions (PSFs) using the GalSIM package to predict the shapes of the PSFs with DCR and wavelength-dependent seeing. We calculate the magnitude corrections and apply them to the magnitudes computed by the DES-SN5YR photometric pipeline. We find that for the DES-SN5YR analysis, not accounting for the astrometric offsets and changes in the PSF shape cause an average bias of +0.2 mmag and −0.3 mmag, respectively, with standard deviations of 0.7 mmag and 2.7 mmag across all DES observing bands ( griz ) throughout all redshifts. When the DCR and seeing effects are not accounted for, we find that w and Ω _m are lower by less than 0.004 ± 0.02 and 0.001 ± 0.01, respectively, with 0.02 and 0.01 being the 1 σ statistical uncertainties. Although we find that these biases do not limit the constraints of the DES-SN5YR sample, future surveys with much higher statistics, lower systematics, and especially those that observe in the u band will require these corrections as wavelength-dependent atmospheric effects are larger at shorter wavelengths. We also discuss limitations of our method and how they can be better accounted for in future surveys.

The ultra-faint dwarf galaxy Reticulum II (Ret II) exhibits a unique chemical evolution history, with ${72}_{-12}^{+10}$ % of its stars strongly enhanced in r -process elements. We present deep Hubble Space Telescope photometry of Ret II and analyze its star formation history. As in other ultra-faint dwarfs, the color–magnitude diagram is best fit by a model consisting of two bursts of star formation. If we assume that the bursts were instantaneous, then the older burst occurred around the epoch of reionization, forming ∼80% of the stars in the galaxy, while the remainder of the stars formed ∼3 Gyr later. When the bursts are allowed to have nonzero durations, we obtain slightly better fits. The best-fitting model in this case consists of two bursts beginning before reionization, with approximately half the stars formed in a short (100 Myr) burst and the other half in a more extended period lasting 2.6 Gyr. Considering the full set of viable star formation history models, we find that 28% of the stars formed within 500 ± 200 Myr of the onset of star formation. The combination of the star formation history and the prevalence of r -process-enhanced stars demonstrates that the r -process elements in Ret II must have been synthesized early in its initial star-forming phase. We therefore constrain the delay time between the formation of the first stars in Ret II and the r -process nucleosynthesis to be less than 500 Myr. This measurement rules out an r -process source with a delay time of several Gyr or more, such as GW170817.

Gravitationally lensed supernovae (LSNe) are important probes of cosmic expansion, but they remain rare and difficult to find. Current cosmic surveys likely contain 5–10 LSNe in total while next-generation experiments are expected to contain several hundred to a few thousand of these systems. We search for these systems in observed Dark Energy Survey (DES) five year SN fields—10 3 sq. deg. regions of sky imaged in the griz bands approximately every six nights over five years. To perform the search, we utilize the DeepZipper approach: a multi-branch deep learning architecture trained on image-level simulations of LSNe that simultaneously learns spatial and temporal relationships from time series of images. We find that our method obtains an LSN recall of 61.13% and a false-positive rate of 0.02% on the DES SN field data. DeepZipper selected 2245 candidates from a magnitude-limited ( m _i < 22.5) catalog of 3,459,186 systems. We employ human visual inspection to review systems selected by the network and find three candidate LSNe in the DES SN fields.

Las cubiertas son la parte más vulnerable de un edificio porque que están expuestas continuamente a las acciones climáticas externas y a su constante variabilidad, ya sea en lo relacionado con la lluvia, nieve, viento, temperatura, agentes biológicos o radiación solar. Por esta razón, dado su gran exposición a todos estos factores, los fallos que pudieran existir en una pequeña área de cubierta son, en la mayoría situaciones, más serios que en otros lugares, dado la velocidad de avance que tienen, así como su repercusión en la habitabilidad. Hace algunos años, una investigación realizada en Australia (en el estado de Victoria) determinó que las cubiertas son el segundo elemento de construcción más afectado por el número de fallos en ese país. En España, las cubiertas son también el segundo capítulo de obra más afectado por patologías, según un estudio de investigación sobre reclamaciones de usuarios. Para averiguar qué irregularidades y mala praxis constructiva se comete durante la ejecución (especialmente filtraciones y humedades, se ha querido analizar cuáles son los fallos más frecuentes en la instalación en obra de la impermeabilización. Para proceder a estudiar los fallos durante la ejecución ha sido necesario recurrir a algún tipo de fuente escrita que pudiera contener esta información. Hay que tener en cuenta que las constructoras en España, salvo casos muy excepcionales, no llevan un registro por escrito de cada una de las deficiencias de puesta en obra o de los incumplimientos normativos que acontezcan. Por tanto, hay que recurrir a las anotaciones que hace la dirección facultativa en el ‘libro de órdenes y visitas’. La investigación llevada a cabo se ha realizado en obras de la provincia de Badajoz, todas de tipo residencial entre 2012 y 2018, sobre las que se ha constatado cuáles son los fallos más frecuentes, haciendo un estudio comparativo entre las promociones que eran de viviendas unifamiliares y las que eran de viviendas en bloque. De esta manera, se pudo constatar que había 10 tipos de fallos que se daban en más del 30% de las ocasiones estudiadas. Especialmente reseñables son los fallos denominados ‘La altura de coronación de la impermeabilización es menor a lo que indica el CTE’ y ‘La cota del umbral está por debajo del nivel de protección de la cubierta’ que tuvieron una presencia superior al 75% de los casos. Abstract The roofs are the most vulnerable part of the building because they are continually exposed to external climatic actions and their constant variability, whether related to rain, snow, wind, temperature, biological agents or solar radiation. For this reason, given their great exposure to all these factors, the faults that may exist in a small cover area are, in most situations, more serious than in other places given the speed of progress they have, as well as their impact on habitability. A few years ago, an investigation carried out in Australia (in the state of Victoria) determined that the roofs are the second building element most affected by the number of failures in that country. In Spain, the covers are also the second chapter of work most affected by pathologies, according to a research study on user complaints. To find out what irregularities and constructive malpractice are committed during the execution (especially filtrations and dampness, it has been wanted to analyze specifically are the most frequent failures in the installation in waterproofing work. To proceed to study the errors during the execution it has been necessary to resort to some type of written source that may contain this information. It must be borne in mind that construction companies in Spain, except for very exceptional cases, do not keep a written record of each of the deficiencies in the implementation or the regulatory breaches that occur. Therefore, the annotations made by the optional address in the "book of orders and visits" must be repeated. The investigation carried out has been carried out in works of the province of Badajoz, all of residential type between 2012 and 2018, on which frequent failures have been found, making a comparative study between the promotions that were of single-family homes and those of block houses. In this way, it was found that there were 10 types of failures that occurred in more than 30% of the studied occasions. Especially noteworthy are the failures called 'The crowning height of the waterproofing is less than what the CTE indicates' and 'The threshold level is below the level of protection of the roof' that had a presence greater than 75% of the cases.

El objetivo de este trabajo es analizar la eficiencia del mantenimiento en un hospital localizado en la provincia de Madrid (España), con 198 camas instaladas y una superficie útil de 23.300 m2 , construido en 2007. Para ello, se estudiaron las siguientes instalaciones: aire acondicionado, agua caliente sanitaria, frio industrial, baja tensión, fontanería, saneamiento, gases medicinales, aire comprimido, protección contra incendios y ascensores. Se comprobó que se utilizaban 2 estrategias de mantenimiento: preventivo y correctivo, que supusieron el 42% y 58% de las incidencias resueltas. El 92,73% de los partes se cierran antes de que transcurran 16 horas, el tiempo medio transcurrido es 45,6 horas en el caso de mantenimiento correctivo y 4,3 horas para el mantenimiento preventivo. El tiempo medio dedicado a la resolución de una incidencia fue de 1,6 horas. Abstract The objective of this work is to analyze the efficiency of maintenance in a hospital located in the province of Madrid (Spain), with 198 beds installed and a useful area of 23,300 m2, built in 2007. For this, the following facilities were studied: air conditioning, domestic hot water, industrial cold, low voltage, plumbing, sanitation, medical gases, compressed air, fire protection and elevators. It was found that 2 maintenance strategies were used: preventive and corrective, which accounted for 42% and 58% of the incidents resolved. 92.73% of the parts are closed before 16 hours have elapsed, the average elapsed time is 45.6 hours in the case of corrective maintenance and 4.3 hours for preventive maintenance. The average time dedicated to the resolution of an incidence was 1.6 hours.

The objective of the analysis presented is to compare the environmental impact of different solutions of roofs according to the CO2 emissions they release into the atmosphere (in kg/m2), as well as the generation of waste (in kg/m2), from the nature of their different constituent layers. For this purpose, waste has been grouped under two criteria: waste per placement and waste per packaging. The analysed roofs are all with a slope of less than 5% (i.e. flat roofs); in order to be more specific, the typologies that were inverted type have been chosen (which means that the insulation was arranged over the waterproofing), given that they are the most commonly used. In addition, only variants with the waterproofing layer consisting of a PVC membrane and three different types of roofs were compared: non-trafficable flat roof finished with gravel (Type A), garden flat roof (Type B) and walkable flat roof with fixed tile flooring (Type C). To make this comparison, the BEDEC database of Instituto de Tecnología de la Construcción (ITEC) has been used and the characterisation of the constituent layers has been carried out according with the LER codes (European Waste List). In addition, life cycle analysis techniques have been used according to the UNE-EN-ISO-14040:2006 and UNE-EN-ISO-14044:2006 standards. It was verified that the least efficient roof with the highest environmental impact values corresponds to Type C. Resumen El análisis que se presenta tiene como finalidad comparar el impacto ambiental de diferentes soluciones de cubiertas según las emisiones de CO2 que vierten a la atmósfera (en kg/m2), así como de la generación de residuos (en kg/m2) a partir de la naturaleza de sus distintas capas constituyentes; esta generación de residuos se ha agrupado bajo dos criterios: residuos por colocación y residuos por embalaje. Las cubiertas analizadas son todas de unidades constructivas con una pendiente inferior al 5% (es decir, cubiertas planas); para concretar más, se han escogido las tipologías que fueran de tipo invertido (lo que conlleva que el aislamiento estuviera dispuesto sobre la impermeabilización), dado que son las más utilizadas. Además, solo se compararon las variantes que tuvieran la capa impermeabilizante constituida por una membrana de PVC y en tres modalidades diferentes de cobertura: cubierta plana no transitable acabada en grava (Tipo A), cubierta plana ajardinada (Tipo B) y cubierta plana transitable con solado fijo de baldosas (Tipo C). Para hacer esta comparativa se ha utilizado la base de datos BEDEC del Instituto de Tecnología de la Construcción (ITEC) y la caracterización de las capas constituyentes se ha realizado según los códigos LER (Lista Europea de Residuos); de igual modo, se han utilizado las técnicas del análisis del ciclo de vida según las normas UNE-EN-ISO-14040:2006 y UNE-EN-ISO-14044:2006. De manera global, la cubierta menos eficiente y con mayores valores de impacto ambiental, corresponde con la Tipo C.

Due to the characteristics of the operation of a hospital, their demand for supplies and the need for uninterruptibility, hospital becomes an energy-intensive building. Currently, energy policies of building operation are based on strategies of energy saving and efficiency. In order to carry them out, it is necessary to get information about the consumption profile of the target building and make decisions based on it. The aim of this work is to analyse the different options for contracting an electricity supply for large consumers, such as hospitals, in an attempt to achieve the greatest savings in energy costs. The possibilities of managing the purchase of energy from these large consumers were discussed and analysed. It was concluded that there is a wide range of contracting possibilities beyond the traditional ones (fixed or indexed contract). It also highlighted the need for qualified personnel to assume the responsibility of studying the different modalities of purchase since it will provide an enormous benefit to hospital management. Resumen Debido a las características del funcionamiento de un hospital, su demanda de suministros y la necesidad de ininterrumpibilidad del mismo, el hospital se convierte en un edificio energéticamente intensivo. En la actualidad, las políticas energéticas de explotación de edificio se basan en estrategias de ahorro y eficiencia energética. Para poder llevarlas a cabo, es necesario disponer de la información acerca del perfil de consumo del edificio objetivo y tomar decisiones en base a ello. El objetivo de este trabajo es analizar las diferentes opciones de contratación del suministro eléctrico para grandes consumidores, como hospitales, presenten el mayor ahorro de costes energéticos. Se discutieron y analizaron las posibilidades de gestión de la compra de energía a estos grandes consumidores. Se destacó como principal conclusión el amplio abanico de posibilidades de contratación más allá de los tradicionales (contrato fijo o indexado). Asimismo, se destacó la necesidad de disponer de personal capacitado para asumir la responsabilidad de estudiar las diferentes modalidades de compra puesto que aportará un enorme beneficio a la gestión hospitalaria.

Today, plans to protect historic buildings focus on managing architectural heritage sustainably. Technical teams, such as architects and restorers, use massive data acquisition techniques, so an identification mechanism is required to select geometrical similarity patters to support hypothesis that guarantee historical data. Moreover, computational methods are required to understand the role of organic shapes in historic buildings. This paper first describes an extensive review of the literature and then the algorithms and methods to compare and to detect similar geometrical elements and complex patterns in architecture and archaeology. For this purpose, two key aspects are considered: the metric standpoint and historical-graphical features of the 3D models, i.e., composition, techniques, styles, and historical-graphical documentary sources. Research implies testing several methodological lines to know the similarity degree of complex organic shapes in architectural details through statistical analysis, software to assess point clouds, and complex curve analysis. The results have shown that the three procedures can be compared and that the bases of the pillars of both the Cathedral of Seville and the churches in Carmona, Jerez, and Morón are very similar; however, the base of the pillar of the church in Carmona presents scalability variations.

Modelling uncertainties at small scales, i.e. high $k$ in the power spectrum $P(k)$, due to baryonic feedback, nonlinear structure growth and the fact that galaxies are biased tracers poses a significant obstacle to fully leverage the constraining power of the Euclid wide-field survey. $k$-cut cosmic shear has recently been proposed as a method to optimally remove sensitivity to these scales while preserving usable information. In this paper we generalise the $k$-cut cosmic shear formalism to $3 \times 2$ point statistics and estimate the loss of information for different $k$-cuts in a $3 \times 2$ point analysis of the {\it Euclid} data. Extending the Fisher matrix analysis of Euclid Collaboration: Blanchard et al. (2019), we assess the degradation in constraining power for different $k$-cuts. We find that taking a $k$-cut at $2.6 \ h \ {\rm Mpc} ^{-1}$ yields a dark energy Figure of Merit (FOM) of 1018. This is comparable to taking a weak lensing cut at $\ell = 5000$ and a galaxy clustering and galaxy-galaxy lensing cut at $\ell = 3000$ in a traditional $3 \times 2$ point analysis. We also find that the fraction of the observed galaxies used in the photometric clustering part of the analysis is one of the main drivers of the FOM. Removing $50 \% \ (90 \%)$ of the clustering galaxies decreases the FOM by $19 \% \ (62 \%)$. Given that the FOM depends so heavily on the fraction of galaxies used in the clustering analysis, extensive efforts should be made to handle the real-world systematics present when extending the analysis beyond the luminous red galaxy (LRG) sample. This paper is published on behalf of the Euclid Consortium: http://euclid-ec.org

While at first it can be thought that the auxiliary elements of facades are merely ornamental with little practical function, this study shows that these components of the building envelope have a high impact on the envelope’s functioning and performance. This is carried out through the analysis of all relevant lawsuits filed in Spain over a 10 year period, a data set in which a surprisingly high number of 1033 cases of defects was found to affect external windowsills, exterior wainscots or cornices (the three auxiliary elements considered) was found. Considering the total number of lawsuits, this is an objectively unprecedented study. An analysis is carried out regarding the interrelations between elements, defects, causes, and types of buildings, with the aim of obtaining a sorted classification of the data. This constitutes a useful tool to prevent future problems arising from either the design, execution, or maintenance of facades. These include various issues resulting from humidities, one of the most frequent envelope defects, which are found to significantly affect the auxiliary elements of facades.