4,481 research outputs found
Evidence for the influence of the mere-exposure effect on voting in the Eurovision Song Contest
The mere exposure, or familiarity, effect is the tendency for people to feel more positive about stimuli to which they have previously been exposed. The Eurovision Song Contest is a two-stage event, in which some contestants in the final will be more familiar to viewers than others. Thus, viewers’ voting is likely to be influenced by this effect. Previous work attempting to demonstrate this effect in this context has been unable to control for contestant quality. The current study, which used a novel procedure to analyse the way in which contestant countries distributed their points (a function of how viewers voted in those countries) between 2008 and 2011, showed that contestants did better if they previously appeared in a semifinal that was seen by voters. This is evidence that the mere exposure effect, alongside previously studied factors such as cultural and geographical closeness, influences the way viewers vote in the Eurovision
Planetary Stability Zones in Hierarchical Triple Star Systems
A symplectic integrator algorithm suitable for hierarchical triple systems is
formulated and tested. The positions of the stars are followed in hierarchical
Jacobi coordinates, whilst the planets are referenced purely to their primary.
The algorithm is fast, accurate and easily generalised to incorporate
collisions. There are five distinct cases -- circumtriple orbits, circumbinary
orbits and circumstellar orbits around each of the stars in the hierarchical
triple -- which require a different formulation of the symplectic integration
algorithm. As an application, a survey of the stability zones for planets in
hierarchical triples is presented, with the case of a single planet orbiting
the inner binary considered in detail. Fits to the inner and outer edges of the
stability zone are computed. Considering the hierarchical triple as two
decoupled binary systems, the earlier work of Holman & Wiegert on binaries is
shown to be applicable to triples, except in the cases of high eccentricities
and close or massive stars. Application to triple stars with good data in the
multiple star catalogue suggests that more than 50 per cent are unable to
support circumbinary planets, as the stable zone is almost non-existent.Comment: 16 pages, MNRAS, in pres
Evolution of the L1 halo family in the radial solar sail CRTBP
We present a detailed investigation of the dramatic changes that occur in the
halo family when radiation pressure is introduced into the
Sun-Earth circular restricted three-body problem (CRTBP). This
photo-gravitational CRTBP can be used to model the motion of a solar sail
orientated perpendicular to the Sun-line. The problem is then parameterized by
the sail lightness number, the ratio of solar radiation pressure acceleration
to solar gravitational acceleration. Using boundary-value problem numerical
continuation methods and the AUTO software package (Doedel et al. 1991) the
families can be fully mapped out as the parameter is increased.
Interestingly, the emergence of a branch point in the retrograde satellite
family around the Earth at acts to split the halo family
into two new families. As radiation pressure is further increased one of these
new families subsequently merges with another non-planar family at
, resulting in a third new family. The linear stability of
the families changes rapidly at low values of , with several small
regions of neutral stability appearing and disappearing. By using existing
methods within AUTO to continue branch points and period-doubling bifurcations,
and deriving a new boundary-value problem formulation to continue the folds and
Krein collisions, we track bifurcations and changes in the linear stability of
the families in the parameter and provide a comprehensive overview of
the halo family in the presence of radiation pressure. The results demonstrate
that even at small values of there is significant difference to the
classical CRTBP, providing opportunity for novel solar sail trajectories.
Further, we also find that the branch points between families in the solar sail
CRTBP provide a simple means of generating certain families in the classical
case.Comment: 31 pages, 17 figures, accepted by Celestial Mechanics and Dynamical
Astronom
(DH) Noise and Signal scaling factors in Digital Holography in week illumination: relationship with Shot Noise
We have performed off axis heterodyne holography with very weak illumination
by recording holograms of the object with and without object illumination in
the same acquisition run. We have experimentally studied, how the reconstructed
image signal (with illumination) and noise background (without) scale with the
holographic acquisition and reconstruction parameters that are the number of
frames, and the number of pixels of the reconstruction spatial filter. The
first parameter is related to the frequency bandwidth of detection in time, the
second one to the bandwidth in space. The signal to background ratio varies
roughly like the inverse of the bandwidth in time and space. We have also
compared the noise background with the theoretical shot noise background
calculated by Monte Carlo simulation. The experimental and Monte Carlo noise
background agree very well together
Phase-resolved heterodyne holographic vibrometry with a strobe local oscillator
We report a demonstration of phase-resolved vibrometry, in which out-of-plane
sinusoidal motion is assessed by heterodyne holography. In heterodyne
holography, the beam in the reference channel is an optical local oscillator
(LO). It is frequency-shifted with respect to the illumination beam to enable
frequency conversion within the sensor bandwidth. The proposed scheme
introduces a strobe LO, where the reference beam is frequency-shifted and
modulated in amplitude, to alleviate the issue of phase retrieval. The strobe
LO is both tuned around the first optical modulation side band at the vibration
frequency, and modulated in amplitude to freeze selected mechanical vibration
states sequentially. The phase map of the vibration can then be derived from
the demodulation of successive vibration states
Social conformity and autism spectrum disorder : a child-friendly take on a classic study
Perhaps surprisingly, given the importance of conformity as a theoretical construct in social psychology and the profound implications autism has for social function, little research has been done on whether autism is associated with the propensity to conform to a social majority. This study is a modern, child-friendly implementation of the classic Asch conformity studies. The performance of 15 children with autism was compared to that of 15 typically developing children on a line judgement task. Children were matched for age, gender and numeracy and literacy ability. In each trial, the child had to say which of three lines a comparison line matched in length. On some trials, children were misled as to what most people thought the answer was. Children with autism were much less likely to conform in the misleading condition than typically developing children. This finding was replicated using a continuous measure of autism traits, the Autism Quotient questionnaire, which showed that autism traits negatively correlated with likelihood to conform in the typically developing group. This study demonstrates the resistance of children with autism to social pressure
Holographic microscopy reconstruction in both object and image half spaces with undistorted 3D grid
We propose an holographic microscopy reconstruction method, which propagates
the hologram, in the object half space, in the vicinity of the object. The
calibration yields reconstructions with an undistorted reconstruction grid i.e.
with orthogonal , and axis and constant pixels pitch. The method is
validated with an USAF target imaged by a 60 microscope objective,
whose holograms are recorded and reconstructed for different USAF locations
along the longitudinal axis: -75 to +75 m. Since the reconstruction
numerical phase mask, the reference phase curvature and MO form an afocal
device, the reconstruction can be interpreted as occurring equivalently in the
object or in image half space
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