Asteroseismic parameters allow us to measure the basic stellar properties of field giants observed far across the Galaxy. Most of such determinations are, up to now, based on simple scaling relations involving the large frequency separation, ∆ν, and the frequency of maximum power, ν max . In this work, we implement ∆ν and the period spacing, ∆P , computed along detailed grids of stellar evolutionary tracks, into stellar isochrones and hence in a Bayesian method of parameter estimation. Tests with synthetic data reveal that masses and ages can be determined with typical precision of 5 and 19 per cent, respectively, provided precise seismic parameters are available. Adding independent information on the stellar luminosity, these values can decrease down to 3 and 10 per cent respectively. The application of these methods to NGC 6819 giants produces a mean age in agreement with those derived from isochrone fitting, and no evidence of systematic differences between RGB and RC stars. The age dispersion of NGC 6819 stars, however, is larger than expected, with at least part of the spread ascribable to stars that underwent mass-transfer events.

We use asteroseismic data from the Kepler satellite to determine fundamental stellar properties of the 66 main-sequence targets observed for at least one full year by the mission. We distributed tens of individual oscillation frequencies extracted from the time series of each star among seven modelling teams who applied different methods to determine radii, masses, and ages for all stars in the sample. Comparisons among the different results reveal a good level of agreement in all stellar properties, which is remarkable considering the variety of codes, input physics and analysis methods employed by the different teams. Average uncertainties are of the order of ∼2% in radius, ∼4% in mass, and ∼10% in age, making this the best-characterised sample of main-sequence stars available to date. Our predicted initial abundances and mixing-length parameters are checked against inferences from chemical enrichment laws ∆Y /∆Z and predictions from 3D atmospheric simulations. We test the accuracy of the determined stellar properties by comparing them to the Sun, angular diameter measurements, Gaia parallaxes, and binary evolution, finding excellent agreement in all cases and further confirming the robustness of asteroseismically-determined physical parameters of stars when individual frequencies of oscillation are available. Baptised as the Kepler dwarfs LEGACY sample, these stars are the solar-like oscillators with the best asteroseismic properties available for at least another decade. All data used in this analysis and the resulting stellar parameters are made publicly available for the community.

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Large-scale analyses of stellar samples comprised of cool, solar-like oscillators now commonly utilize the so-called asteroseismic scaling relations to estimate fundamental stellar properties. In this paper we present a test of the scaling relation for the global asteroseismic parameter ν max , the frequency at which a solar-like oscillator presents its strongest observed pulsation amplitude. The classic relation assumes that this characteristic frequency scales with a particular combination of surface gravity and effective temperature that also describes the dependence of the cut-off frequency for acoustic waves in an isothermal atmosphere, i.e., ν max ∝ gT −1/2 eff . We test how well the oscillations of cool main-sequence and sub-giant stars adhere to this relation, using a sample of asteroseismic targets observed by the NASA Kepler Mission. Our results, which come from a grid-based analysis, rule out departures from the classic gT −1/2 eff scaling dependence at the level of ≃ 1.5 percent over the full ≃ 1560 K range in T eff that we tested. There is some uncertainty over the absolute calibration of the scaling. However, any variation with T eff is evidently small, with limits similar to those above.

With the appearance of innovative virtual reality (VR) technologies, the need to create immersive content arose. Although there are already some non-immersive solutions to address immersive audio-visual content, there are no solutions that allow the creation of immersive multisensory content. This work proposes a novel architecture for a collaborative immersive tool that allows the creation of multisensory VR experiences in real-time, thus promoting the expeditious development, adoption, and use of immersive systems and enabling the building of custom-solutions that can be used in an intuitive manner to support organizations' business initiatives. To validate the presented proposal, two approaches for the authoring tools (Desktop interface and Immersive interface) were subjected to a set of tests and evaluations consisting of a usability study that demonstrated not only the participants' acceptance of the authoring tool but also the importance of using immersive interfaces for the creation of such VR experiences.

For this span range (70-90 m), as recent studies have proven, 1 the spanby-span construction also ensures important advantages such as continuity of the deck and a significant optimization of material consumption (in particular that of prestressing steel) because the construction stage may be almost neutral to the deck design.Until the last few years, bridges with 70 to 90 m span were typically constructed by precast solutions, metallic solutions or cantilever method. 2

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We present the first detections by the NASA K2 Mission of oscillations in solar-type stars, using short-cadence data collected during K2 Campaign 1 (C1). We understand the asteroseismic detection thresholds for C1-like levels of photometric performance, and we can detect oscillations in subgiants having dominant oscillation frequencies around 1000 µHz. Changes to the operation of the fine-guidance sensors are expected to give significant improvements in the high-frequency performance from C3 onwards. A reduction in the excess highfrequency noise by a factor of two-and-a-half in amplitude would bring mainsequence stars with dominant oscillation frequencies as high as ≃ 2500 µHz into play as potential asteroseismic targets for K2.