•Over 20% of energy poverty cases increase with monthly studies.•Monthly variation is independent of dwellings’ technical characteristics.•Users’ behaviour pattern does not affect monthly tendencies.
...Energy poverty has been addressed as a global problem. Many studies have been conducted, and several indicators have been established to detect energy poverty. However, most analyses have been performed at a yearly level without considering the differences throughout the year. This study performed a sensitivity analysis to determine these differences using the 2 M indicator in 36,230,400 case studies in the south of Spain, which is a warm zone with great energy poverty, as well as vulnerable to climate change effects. The results showed that monthly assessment could increase energy poverty situations in the months with greater climate severity, compared to yearly assessment. That increase in winter and summer months raised energy poverty cases over 20 %, with these months being those with greater vulnerability due to cold and heat waves, respectively. The results also showed that variations were independent of both the technical characteristics of the dwelling and the use of HVAC systems. Energy poverty cases were reduced only in the summer months with the adaptive approach, which considers thermal adaptation. The use of the 2 M indicator in monthly scales can detect vulnerable family units that cannot be detected by yearly studies, so monthly scales are crucial for governments to adopt energy poverty policies and strategies.
•Performing monthly analyses of energy poverty to find critical months.•A total of 6528 cases are used to assess energy poverty.•Applying adaptive setpoints to reduce energy poverty.
The reduction of ...energy poverty is among the main current challenges. One of the recent approaches is based on the reduction of the energy consumption through the climate adaptability of users. This research analyses the possibility of using adaptive setpoint temperatures to reduce the risk of energy poverty. A total of 6528 cases are considered in the south of Spain in 2015 and 2016 with actual data of temperature, hourly prices from the Voluntary Price for the Small Consumer, and the mean household incomes in both years. The energy consumption and expense are compared to both the static setpoints established by the Spanish Technical Building Code and the adaptive setpoints based on EN 16798-1:2019. In the annual calculation, by using both static and adaptive setpoints, the results show that the situation of energy poverty would only affect the family units belonging to the first decile of incomes. However, a monthly analysis identifies that the coldest or warmest months influence more deciles: for example, January 2015 affected until decile 8. The results also show that adaptive setpoints could reduce the risk of energy poverty in most cases, being more significant in Categories II and III from EN 16798-1:2019, in which this risk is reduced in all months of the year and in all deciles. This study aims to throw light on the use of HVAC systems according to the adaptation of users to reduce monthly the risk of energy poverty.
Eoandromeda octobrachiata is a poorly understood Ediacaran organism, with spiral octoradial arms, found in South Australia and South China. The informal Nilpena member of the Rawnsley Quartzite, ...Flinders Ranges in South Australia preserves more than 200 specimens of Eoandromeda. Here we use the novel application of rotational geometric morphometrics together with palaeoenvironmental information to provide a better insight into their palaeobiology and ecology, and to address conflicting hypotheses regarding mode of life and taxonomic affinity. We find that Eoandromeda probably had a radially symmetrical shape in life, was cone shaped and had a high relief off the microbial mat. Analysis of the symmetric and asymmetric shape components showed that they deform strongly in the direction of palaeocurrent, therefore they are thought to be made of a flexible material. Almost all specimens are compressed flat. Specimens that appear to have not fully collapsed support the idea that Eoandromeda was probably cone shaped and suggest that they possibly collapsed spirally. Our shape analysis, along with observed morphological features, support a benthic rather than pelagic mode of life. Morphological and ecological inconsistencies do not fully support the hypothesis of a Ctenophora taxonomic affinity.
Abstract
We present a detailed abundance analysis of the three brightest member stars at the top of the giant branch of the ultrafaint dwarf (UFD) galaxy Grus II. All stars exhibit a higher than ...expected Mg/Ca ratio compared to metal-poor stars in other UFD galaxies and in the Milky Way (MW) halo. Nucleosynthesis in high-mass (
20
M
⊙
) core-collapse supernovae has been shown to create this signature. The abundances of this small sample (three) stars suggests the chemical enrichment of Grus II could have occurred through substantial high-mass stellar evolution, and is consistent with the framework of a top-heavy initial mass function. However, with only three stars it cannot be ruled out that the abundance pattern is the result of a stochastic chemical enrichment at early times in the galaxy. The most metal-rich of the three stars also possesses a small enhancement in rapid neutron-capture (
r
-process) elements. The abundance pattern of the
r
-process elements in this star matches the scaled
r
-process pattern of the solar system and
r
-process enhanced stars in other dwarf galaxies and in the MW halo, hinting at a common origin for these elements across a range of environments. All current proposed astrophysical sites of
r
-process element production are associated with high-mass stars, thus the possible top-heavy initial mass function of Grus II would increase the likelihood of any of these events occurring. The time delay between the
α
and
r
-process element enrichment of the galaxy favors a neutron star merger as the origin of the
r
-process elements in Grus II.
ABSTRACT
We present a sample of 19 583 ultracool dwarf candidates brighter than z ≤23 selected from the Dark Energy Survey DR2 coadd data matched to VHS DR6, VIKING DR5, and AllWISE covering ∼ 480 ...deg2. The ultracool candidates were first pre-selected based on their (i–z), (z–Y), and (Y–J) colours. They were further classified using a method that compares their optical, near-infrared, and mid-infrared colours against templates of M, L, and T dwarfs. 14 099 objects are presented as new L and T candidates and the remaining objects are from the literature, including 5342 candidates from our previous work. Using this new and deeper sample of ultracool dwarf candidates we also present: 20 new candidate members to nearby young moving groups and associations, variable candidate sources and four new wide binary systems composed of two ultracool dwarfs. Finally, we also show the spectra of 12 new ultracool dwarfs discovered by our group and presented here for the first time. These spectroscopically confirmed objects are a sanity check of our selection of ultracool dwarfs and photometric classification method.
ABSTRACT
Strongly lensed quadruply imaged quasars (quads) are extraordinary objects. They are very rare in the sky and yet they provide unique information about a wide range of topics, including the ...expansion history and the composition of the Universe, the distribution of stars and dark matter in galaxies, the host galaxies of quasars, and the stellar initial mass function. Finding them in astronomical images is a classic ‘needle in a haystack’ problem, as they are outnumbered by other (contaminant) sources by many orders of magnitude. To solve this problem, we develop state-of-the-art deep learning methods and train them on realistic simulated quads based on real images of galaxies taken from the Dark Energy Survey, with realistic source and deflector models, including the chromatic effects of microlensing. The performance of the best methods on a mixture of simulated and real objects is excellent, yielding area under the receiver operating curve in the range of 0.86–0.89. Recall is close to 100 per cent down to total magnitude i ∼ 21 indicating high completeness, while precision declines from 85 per cent to 70 per cent in the range i ∼ 17–21. The methods are extremely fast: training on 2 million samples takes 20 h on a GPU machine, and 108 multiband cut-outs can be evaluated per GPU-hour. The speed and performance of the method pave the way to apply it to large samples of astronomical sources, bypassing the need for photometric pre-selection that is likely to be a major cause of incompleteness in current samples of known quads.
We present a catalog of 4195 optically confirmed Sunyaev-Zel'dovich (SZ) selected galaxy clusters detected with signal-to-noise ratio >4 in 13,211 deg2 of sky surveyed by the Atacama Cosmology ...Telescope (ACT). Cluster candidates were selected by applying a multifrequency matched filter to 98 and 150 GHz maps constructed from ACT observations obtained from 2008 to 2018 and confirmed using deep, wide-area optical surveys. The clusters span the redshift range 0.04 < z < 1.91 (median z = 0.52). The catalog contains 222 z > 1 clusters, and a total of 868 systems are new discoveries. Assuming an SZ signal versus mass-scaling relation calibrated from X-ray observations, the sample has a 90% completeness mass limit of M500c > 3.8 × 1014 M , evaluated at z = 0.5, for clusters detected at signal-to-noise ratio >5 in maps filtered at an angular scale of 2 4. The survey has a large overlap with deep optical weak-lensing surveys that are being used to calibrate the SZ signal mass-scaling relation, such as the Dark Energy Survey (4566 deg2), the Hyper Suprime-Cam Subaru Strategic Program (469 deg2), and the Kilo Degree Survey (825 deg2). We highlight some noteworthy objects in the sample, including potentially projected systems, clusters with strong lensing features, clusters with active central galaxies or star formation, and systems of multiple clusters that may be physically associated. The cluster catalog will be a useful resource for future cosmological analyses and studying the evolution of the intracluster medium and galaxies in massive clusters over the past 10 Gyr.
We present the analysis underpinning the measurement of cosmological parameters from 207 spectroscopically classified SNe Ia from the first 3 years of the Dark Energy Survey Supernova Program ...(DES-SN), spanning a redshift range of 0.017 < z < 0.849. We combine the DES-SN sample with an external sample of 122 low-redshift (z < 0.1) SNe Ia, resulting in a "DES-SN3YR" sample of 329 SNe Ia. Our cosmological analyses are blinded: after combining our DES-SN3YR distances with constraints from the Cosmic Microwave Background, our uncertainties in the measurement of the dark energy equation-of-state parameter, w, are 0.042 (stat) and 0.059 (stat+syst) at 68% confidence. We provide a detailed systematic uncertainty budget, which has nearly equal contributions from photometric calibration, astrophysical bias corrections, and instrumental bias corrections. We also include several new sources of systematic uncertainty. While our sample is less than one-third the size of the Pantheon sample, our constraints on w are only larger by 1.4×, showing the impact of the DES-SN Ia light-curve quality. We find that the traditional stretch and color standardization parameters of the DES-SNe Ia are in agreement with earlier SN Ia samples such as Pan-STARRS1 and the Supernova Legacy Survey. However, we find smaller intrinsic scatter about the Hubble diagram (0.077 mag). Interestingly, we find no evidence for a Hubble residual step (0.007 0.018 mag) as a function of host-galaxy mass for the DES subset, in 2.4 tension with previous measurements. We also present novel validation methods of our sample using simulated SNe Ia inserted in DECam images and using large catalog-level simulations to test for biases in our analysis pipelines.
Adaptive thermal comfort has gained momentum within the scientific community as a cost effective and affordable way of maintaining acceptable levels of comfort in dwellings while abating energy ...expenditure. At the moment two international standards, namely the European EN16798-1 and the American ASHRAE55-2010 shape the understanding of adaptive comfort around the world. However, in recent years concerns have raised about whether they can accurately represent comfort conditions considering the cultural and societal background of different countries, and whether adaptive thermal comfort will be still feasible in future scenarios of climate change. Considering these challenges, this study presents an algorithm which can model different adaptive comfort models; additionally, it can be implemented into energy simulation engines and therefore used to predict energy consumption under different climates, building typologies, and dynamic comfort conditions. This contribution presents the development of the aforementioned algorithm, called ACCIS (Adaptive-Comfort-Control-Implementation Script), originally written in EnergyPlus Runtime Language (ERL) and later nested in a Python package called ACCIM (Adaptive-Comfort-Control-Implemented Model)”, its main characteristics, and also the implementation into two cases studies: The thermal comfort in social dwellings in Spain and Japan considering present and future climate change scenarios namely Representative Concentration Pathways (RCP) 2.6, 4.5 and 8.5 for years 2050, 2080 and 2100. The results show that the predicted energy consumption of low-income families is strongly influenced by the adaptive comfort model chosen to model their thermal routine and suggest that international standards should be put under revision to consider the local particularities of dwellers in subsidized housing projects. The results of this research can be useful to devise public policies aimed at abating energy cost for low-income dwellers that benefit from social housing programs, particularly in the light of the increment of energy costs for heating and cooling associated with climate change..
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