arXiv subjects

James Lewis

Publications and source records attributed to James Lewis.

5 recordsLinked to original sources

arXiv2019

Immersive VR as a Tool to Enhance Relaxation for Undergraduate Students with the Aim of Reducing Anxiety - A Pilot Study

Despite extensive use in related domains, Virtual Reality (VR) for generalised anxiety disorder (GAD) has received little previous attention. We report upon a VR environment created for the Oculus Rift and Unreal Engine 4 (UE4) to investigate the potential of a VR simulation to be used as an anxiety management tool. We introduce the broad topic of GAD and related publications on the application of VR to this, and similar, mental health conditions. We then describe the development of a real time simulation tool, based upon the passive VR experience of a tranquil, rural alpine scene experienced from a seated position with head tracking. Evaluation focused upon qualitative feedback on the application. Testing was carried out over the period of two weeks on a sample group of eleven students studying at Nottingham Trent University. All participants were asked to complete the Depression, Anxiety and Stress Scale - 21 Items (DASS21) at the beginning and at the end of the study order to assess their profile, and hence suitability to comment upon the software. Qualitative feedback was very encouraging, with all participants reporting that they believed the experience helped and that they would consider utilising it if it was available. Additionally, a psychologist was asked to test the application to provide a specialist opinion on whether it would be appropriate for use as an anxiety management tool. The results highlight several areas for improvement but are positive overall in terms of its potential as a therapeutic tool.

cs.HC↗

arXiv2018

Gaia-ESO Survey: INTRIGOSS - A new library of High Resolution Synthetic Spectra

We present a high resolution synthetic spectral library, INTRIGOSS, designed for studying FGK stars. The library is based on atmosphere models computed with specified individual element abundances via ATLAS12 code. Normalized SPectra (NSP) and surface Flux SPectra (FSP), in the 4830-5400 A, wavelength range, were computed with the SPECTRUM code. INTRIGOSS uses the solar composition by Grevesse et al. 2007 and four [alpha/Fe] abundance ratios and consists of 15,232 spectra. The synthetic spectra are computed with astrophysical gf-values derived by comparing synthetic predictions with a very high SNR solar spectrum and the UVES-U580 spectra of five cool giants. The validity of the NSPs is assessed by using the UVES-U580 spectra of 2212 stars observed in the framework of the Gaia-ESO Survey and characterized by homogeneous and accurate atmospheric parameter values and by detailed chemical compositions. The greater accuracy of NSPs with respect to spectra from the AMBRE, GES_Grid, PHOENIX, C14, and B17 synthetic spectral libraries is demonstrated by evaluating the consistency of the predictions of the different libraries for the UVES-U580 sample stars. The validity of the FSPs is checked by comparing their prediction with both observed spectral energy distribution and spectral indices. The comparison of FSPs with SEDs derived from ELODIE, INDO--U.S., and MILES libraries indicates that the former reproduce the observed flux distributions within a few percent and without any systematic trend. The good agreement between observational and synthetic Lick/SDSS indices shows that the predicted blanketing of FSPs well reproduces the observed one, thus confirming the reliability of INTRIGOSS FSPs.

astro-ph.SR↗

arXiv2017

The Business of Height Pairings

In algebraic geometry there is the notion of a height pairing of algebraic cycles, which lies at the confluence of arithmetic, Hodge theory and topology. After explaining a motivating example situation, we introduce new directions in this subject.

math.AG↗

arXiv2012

Normal functions, Picard-Fuchs equations, and elliptic fibrations on K3 surfaces

Using Gauss-Manin derivatives of normal functions, we arrive at some remarkable results on the non-triviality of the transcendental regulator for $K_m$ of a very general projective algebraic manifold. Our strongest results are for the transcendental regulator for $K_1$ of a very general $K3$ surface. We also construct an explicit family of $K_1$ cycles on $H \oplus E_8 \oplus E_8$-polarized $K3$ surfaces, and show they are indecomposable by a direct evaluation of the real regulator. Critical use is made of natural elliptic fibrations, hypersurface normal forms, and an explicit parametrization by modular functions.

math.AG↗

arXiv2004

The Abel-Jacobi map for higher Chow groups

We construct a map between Bloch's higher Chow groups and Deligne homology for smooth, complex quasiprojective varieties on the level of complexes. For complex projective varieties this results in a formula which generalizes at the same time the classical Griffiths Abel-Jacobi map and the Borel/Beilinson/Goncharov regulator type maps.

math.AG↗