4,962 research outputs found

    Automated sunspot detection and the evolution of sunspot magnetic fields during solar cycle 23

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    The automated detection of solar features is a technique which is relatively underused but if we are to keep up with the flow of data from spacecraft such as the recently launched Solar Dynamics Observatory, then such techniques will be very valuable to the solar community. Automated detection techniques allow us to examine a large set of data in a consistent way and in relatively short periods of time allowing for improved statistics to be carried out on any results obtained. This is particularly useful in the field of sunspot study as catalogues can be built with sunspots detected and tracked without any human intervention and this provides us with a detailed account of how various sunspot properties evolve over time. This article details the use of the Sunspot Tracking And Recognition Algorithm (STARA) to create a sunspot catalogue. This catalogue is then used to analyse the magnetic fields in sunspot umbrae from 1996-2010, taking in the whole of solar cycle 23.Comment: Submitted to the proceedings of IAU Symposium 273 : The Physics of Sun and Star Spot

    Mathematical morphology and applications in automated sunspot detection

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    This presentation discusses the mathematical morphology and applications in automated sunspot detection

    Interview: Tony Reekie

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    In 2015, Tony Reekie stood down as Director of Imaginate, Scotland’s national art-form development organisation for theatre for young audiences. Tony had programmed the annual Imaginate Festival of performing arts for children and young people since 2000, bringing companies from around the world to Edinburgh each May to share their work. Prior to joining Imaginate in 1996, Tony worked with a host of well-known Scottish theatre companies, including 7:84, TAG and Visible Fictions. In this interview, he reflects on the changes he’s observed within children’s theatre over the past two decades. He discusses taboos, funding, art for babies, nationhood and theatre as a political act, presenting Scotland as a site of distinctive practices and aesthetic modalities.Publisher PD

    Measurements of the Muon Content of UHECR Air Showers with the Pierre Auger Observatory

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    The Pierre Auger Observatory, recently completed, has been operational since 2004. As a hybrid experiment, it allows for a wide range of measurements of UHECR-induced extensive air showers (EAS), including measurements of the EAS particle content on ground which is sensitive to high-energy hadronic interactions. We present the results of several independent measurements of the EAS muon content on ground in Auger data at a primary energy of 10 EeV. We discuss implications on high-energy hadronic interaction models and cosmic ray composition.Comment: 6 pages, 5 figures; proceedings of ISVHECRI 2008 - XV International Symposium on Very High Energy Cosmic Ray Interaction

    The rate of cosmic ray showers at large zenith angles: a step towards the detection of ultra-high energy neutrinos by the Pierre Auger Observatory

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    It is anticipated that the Pierre Auger Observatory can be used to detect cosmic neutrinos of >10^19 eV that arrive at very large zenith angles. However showers created by neutrino interactions close to the detector must be picked out against a background of similar events initiated by cosmic ray nuclei. As a step towards understanding this background, we have made the first detailed analysis of air showers recorded at Haverah Park (an array which used similar detectors to those planned for the Auger Observatory) with zenith angles above 60 degs. We find that the differential shower rate from 60 degs to 80 degs. can be predicted accurately when we adopt the known primary energy spectrum above 10^17 eV and assume the QGSJET model and proton primaries. Details of the calculation are given.Comment: 22 pages, 12 figures, to appear in Astroparticle Physic

    The influence of social and symbolic cues on observers' gaze behaviour

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    Research has shown that social and symbolic cues presented in isolation and at fixation have strong effects on observers, but it is unclear how cues compare when they are presented away from fixation and embedded in natural scenes. We here compare the effects of two types of social cue (gaze and pointing gestures) and one type of symbolic cue (arrow signs) on eye movements of observers under two viewing conditions (free viewing vs. a memory task). The results suggest that social cues are looked at more quickly, for longer and more frequently than the symbolic arrow cues. An analysis of saccades initiated from the cue suggests that the pointing cue leads to stronger cueing than the gaze and the arrow cue. While the task had only a weak influence on gaze orienting to the cues, stronger cue following was found for free viewing compared to the memory task

    Simulation of Ultra-High Energy Photon Propagation in the Geomagnetic Field

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    The identification of primary photons or specifying stringent limits on the photon flux is of major importance for understanding the origin of ultra-high energy (UHE) cosmic rays. We present a new Monte Carlo program allowing detailed studies of conversion and cascading of UHE photons in the geomagnetic field. The program named PRESHOWER can be used both as an independent tool or together with a shower simulation code. With the stand-alone version of the code it is possible to investigate various properties of the particle cascade induced by UHE photons interacting in the Earth's magnetic field before entering the Earth's atmosphere. Combining this program with an extensive air shower simulation code such as CORSIKA offers the possibility of investigating signatures of photon-initiated showers. In particular, features can be studied that help to discern such showers from the ones induced by hadrons. As an illustration, calculations for the conditions of the southern part of the Pierre Auger Observatory are presented.Comment: 41 pages, 9 figures, added references in introduction, corrected energy in row 1 of Table 3, extended caption of Table

    A review of Websites and Mobile Applications for People with Autism Spectrum Disorders: Towards Shared Guidelines

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    Many studies show the effective positive impact of using computer technologies to support the lives of users with autism spectrum disorders (ASD), for simplifying interaction with other people, for organising daily activities, for improving relation with family and friends. Despite that, only a restricted part of the current websites is accessible for people with ASD. In this paper, we discuss a set of guidelines that should be followed by designers while developing websites or mobile applications for users with ASD. We review many of the existing websites and applications in order to check which comply with all, or parts of these guidelines. We finally highlight current common limitations and address new challenging research directions. \ua9 ICST Institute for Computer Sciences, Social Informatics and Telecommunications Engineering 2017
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