2,993 research outputs found
Assessing the spatial structure of population variables in England and Wales
Areas within England and Wales have population profiles that make them distinct from other locales; some areas have lower unemployment rates than others, while, in some places, there is a greater mix of ethnic groups than elsewhere. Thus, the degree of difference between areas differs geographically and between population subāgroups. Being able to measure change in these differences is crucial in assessing whether the population has become more or less similar over time. The spatial distribution of the population by, for example, ethnicity or employment status can be characterised and the resulting measures show how the population is geographically organised, and how this changes through time. For example, spatial concentrations of the population by age may be less obvious locally (e.g. within a town or city) or regionally (e.g. the north west of England) than by housing tenure. This paper makes two key contributions: (i) it introduces methods for the analysis of spatial distributions of population subāgroups and (ii) enhances our understanding of the characteristics of population subāgroups in England and Wales and how they have changed over time. Based on Census data for Output Areas, the analysis uses the index of dissimilarity, Moran's I autocorrelation coefficient and the variogram to measure (spatial) variation in variables representing population subāgroups by age, ethnic group, housing tenure, car or van ownership, qualifications, employment, limiting long term illness and National Statistics Socioāeconomic Classification. The analysis shows that, between 2001 and 2011, unevenness in most population subāgroups reduced and the populations in individual Census zones across England and Wales became more similar. Neighbouring Census zones also became more similar (more āclusteredā). The findings suggest that there were decreased differences both within and between regions for many population variables between 2001 and 2011
Towards the improvement of self-service systems via emotional virtual agents
Affective computing and emotional agents have been found to have a positive effect on human-computer interactions. In order to develop an acceptable emotional agent for use in a self-service interaction, two stages of research were identified and carried out; the first to determine which facial expressions are present in such an interaction and the second to determine which emotional agent behaviours are perceived as appropriate during a problematic self-service shopping task. In the first stage, facial expressions associated with negative affect were found to occur during self-service shopping interactions, indicating that facial expression detection is suitable for detecting negative affective states during self-service interactions. In the second stage, user perceptions of the emotional facial expressions displayed by an emotional agent during a problematic self-service interaction were gathered. Overall, the expression of disgust was found to be perceived as inappropriate while emotionally neutral behaviour was perceived as appropriate, however gender differences suggested that females perceived surprise as inappropriate. Results suggest that agents should change their behaviour and appearance based on user characteristics such as gender
Parallel-propagating Fluctuations at Proton-kinetic Scales in the Solar Wind are Dominated by Kinetic Instabilities
We use magnetic helicity to characterise solar wind fluctuations at
proton-kinetic scales from Wind observations. For the first time, we separate
the contributions to helicity from fluctuations propagating at angles
quasi-parallel and oblique to the local mean magnetic field, . We
find that the helicity of quasi-parallel fluctuations is consistent with
Alfv\'en-ion cyclotron and fast magnetosonic-whistler modes driven by proton
temperature anisotropy instabilities and the presence of a relative drift
between -particles and protons. We also find that the helicity of
oblique fluctuations has little dependence on proton temperature anisotropy and
is consistent with fluctuations from the anisotropic turbulent cascade. Our
results show that parallel-propagating fluctuations at proton-kinetic scales in
the solar wind are dominated by proton temperature anisotropy instabilities and
not the turbulent cascade. We also provide evidence that the behaviour of
fluctuations at these scales is independent of the origin and macroscopic
properties of the solar wind.Comment: Accepted for publication in ApJL. 6 Pages, 3 figures, 1 tabl
An Infrasonic Missing Fundamental Rises at 18.5Hz
The Missing Fundamental (MF) phenomenon is an auditory processing artifact which arises from the perception of a harmonically-structured complex sound in the absence of the complex soundās fundamental frequency (f0). Constructive interference occurring between constituent waveforms of the harmonic series may elicit a perceptible tone at the f0ās pitch. A related illusion, known as binaural auditory beats (BAB), may also generate nonexistent perceptible pitches through a shared mechanism. A harmonic series suggesting to an infrasonic f0 (1/f) noise and broken MF conditions. This data suggests that an infrasonic MF tone is generated, despite the normally imperceptible nature of the sound. The computational phenomenon reported here may also occur throughout the cortex, where it could influence or induce different conscious states. The practical implications of altering cortical activity is relevant in understanding processing disorders such as Attention Deficit Hyperactivity Disorder and Schizophrenia
The Role of Proton-Cyclotron Resonance as a Dissipation Mechanism in Solar Wind Turbulence: A Statistical Study at Ion-Kinetic Scales
We use magnetic field and ion moment data from the MFI and SWE instruments
onboard the Wind spacecraft to study the nature of solar wind turbulence at
ion-kinetic scales. We analyze the spectral properties of magnetic field
fluctuations between 0.1 and 5.5 Hz over 2012 using an automated routine,
computing high-resolution 92 s power and magnetic helicity spectra. To ensure
the spectral features are physical, we make the first in-flight measurement of
the MFI `noise-floor' using tail-lobe crossings of the Earth's magnetosphere
during early 2004. We utilize Taylor's hypothesis to Doppler-shift into the
spacecraft frequency frame, finding that the spectral break observed at these
frequencies is best associated with the proton-cyclotron resonance scale,
, compared to the proton inertial length and proton gyroscale
. This agreement is strongest when we consider periods where
, and is consistent with a spectral break at for
and for . We also find that
the coherent magnetic helicity signature observed at these frequencies is
bounded at low frequencies by and its absolute value reaches a maximum
at . These results hold in both slow and fast wind streams, but with a
better correlation in the more Alfv\'enic fast wind where the helicity
signature is strongest. We conclude that these findings are consistent with
proton-cyclotron resonance as an important mechanism for dissipation of
turbulent energy in the solar wind, occurring at least half the time in our
selected interval. However, we do not rule out additional mechanisms.Comment: 16 pages, 11 figures. Accepted for publication in The Astrophysical
Journal. Please contact authors to obtain WIND MFI 'noise-floor' for use in
other studie
Literacy: A Continuously Evolving Concept
Angelo P. Giardino, Robert Sanborn, William V. Flores and E. Christopher Lloyd discuss the latest issue of the Journal of Family Strengths
Narrow heavy-hole cyclotron resonances split by the cubic Rashba spin-orbit interaction in strained germanium quantum wells
The spin-orbit interaction was found to split the cyclotron resonance of heavy holes confined in high-mobility, compressively strained germanium quantum wells. The interference between coherent spin-split cyclotron resonances was tracked on picosecond time scales using terahertz time-domain spectroscopy. Analysis in the time domain, or using a time-frequency decomposition based on the Gabor-Morlet wavelet, was necessary when the difference between cyclotron frequencies was comparable to the linewidth. The cubic Rashba spin-orbit coefficient Ī² was determined via two methods: (i) the magnetic-field dependence of the cyclotron frequencies, and (ii) the spin-resolved subband densities. An enhanced Ī² and spin polarization was created by tailoring the strain to enhance the spin-orbit interaction. The amplitude modulation of the narrow, interfering cyclotron resonances is a signature of spin coherences persisting for more than 10 ps
Engineering robust polar chiral clathrate crystals
This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ Royal Society of Chemistry 2013.The R-(+)-enantiomeric form of Dianin's compound and the S-(+)-enantiomeric form of its direct thiachroman analogue both obtained chromatographically employing a cellulose tris(3,5-dimethylphenylcarbamate) column, are shown to undergo supramolecular assembly to form a polar clathrate lattice which is stable even in the absence of a consolidating guest component
Deep GALEX UV Survey of the Kepler Field. I. Point Source Catalog
We report observations of a deep near-ultraviolet (NUV) survey of the Kepler field made in 2012 with the Galaxy Evolution Explorer (GALEX) Complete All-Sky UV Survey Extension (CAUSE). The GALEX-CAUSE Kepler survey (GCK) covers 104 square degrees of the Kepler field and reaches a limiting magnitude of NUV ~ 22.6 at 3Ļ. Analysis of the GCK survey has yielded a catalog of 669,928 NUV sources, of which 475,164 are cross-matched with stars in the Kepler Input Catalog. Approximately 327 of 451 confirmed exoplanet host stars and 2614 of 4696 candidate exoplanet host stars identified by Kepler have NUV photometry in the GCK survey. The GCK catalog should enable the identification and characterization of UV-excess stars in the Kepler field (young solar-type and low-mass stars, chromospherically active binaries, white dwarfs, horizontal branch stars, etc.), and elucidation of various astrophysics problems related to the stars and planetary systems in the Kepler field
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