226 research outputs found
On the large-scale angular distribution of short-Gamma ray bursts
We investigate the large-scale angular distribution of the short-Gamma ray
bursts (SGRBs) from BATSE experiment, using a new coordinates-free method. The
analyses performed take into account the angular correlations induced by the
non-uniform sky exposure during the experiment, and the uncertainty in the
measured angular coordinates. Comparising the large-scale angular correlations
from the data with those expected from simulations using the exposure function
we find similar features. Additionally, confronting the large-angle
correlations computed from the data with those obtained from simulated maps
produced under the assumption of statistical isotropy we found that they are
incompatible at 95% confidence level. However, such differences are restricted
to the angular scales 36o - 45o, which are likely to be due to the non-uniform
sky exposure. This result strongly suggests that the set of SGRBs from BATSE
are intrinsically isotropic. Moreover, we also investigated a possible
large-angle correlation of these data with the supergalactic plane. No evidence
for such large-scale anisotropy was found.Comment: Accepted for publication in The Astrophysical Journal, 6 pages, 3
figure
A boundary integral equation method in the frequency domain for cracks under transient loading
Acknowledgments The financial support of the German Academic Exchange Service (DAAD), Engineering and Physical Sciences Research Council (EPSRC) and Advanced Research Collaboration (ARC) Programme (funded by the British Council and DAAD) is gratefully acknowledged.Peer reviewedPublisher PD
A Bayesian estimate of the CMB-large-scale structure cross-correlation
Evidences for late-time acceleration of the Universe are provided by multiple
probes, such as Type Ia supernovae, the cosmic microwave background (CMB) and
large-scale structure (LSS). In this work, we focus on the integrated
Sachs--Wolfe (ISW) effect, i.e., secondary CMB fluctuations generated by
evolving gravitational potentials due to the transition between, e.g., the
matter and dark energy (DE) dominated phases. Therefore, assuming a flat
universe, DE properties can be inferred from ISW detections. We present a
Bayesian approach to compute the CMB--LSS cross-correlation signal. The method
is based on the estimate of the likelihood for measuring a combined set
consisting of a CMB temperature and a galaxy contrast maps, provided that we
have some information on the statistical properties of the fluctuations
affecting these maps. The likelihood is estimated by a sampling algorithm,
therefore avoiding the computationally demanding techniques of direct
evaluation in either pixel or harmonic space. As local tracers of the matter
distribution at large scales, we used the Two Micron All Sky Survey (2MASS)
galaxy catalog and, for the CMB temperature fluctuations, the ninth-year data
release of the Wilkinson Microwave Anisotropy Probe (WMAP9). The results show a
dominance of cosmic variance over the weak recovered signal, due mainly to the
shallowness of the catalog used, with systematics associated with the sampling
algorithm playing a secondary role as sources of uncertainty. When combined
with other complementary probes, the method presented in this paper is expected
to be a useful tool to late-time acceleration studies in cosmology.Comment: 21 pages, 15 figures, 4 tables. We extended the previous analyses
including WMAP9 Q, V and W channels, besides the ILC map. Updated to match
accepted ApJ versio
A Fine-Grained Dataset and its Efficient Semantic Segmentation for Unstructured Driving Scenarios
Research in autonomous driving for unstructured environments suffers from a
lack of semantically labeled datasets compared to its urban counterpart. Urban
and unstructured outdoor environments are challenging due to the varying
lighting and weather conditions during a day and across seasons. In this paper,
we introduce TAS500, a novel semantic segmentation dataset for autonomous
driving in unstructured environments. TAS500 offers fine-grained vegetation and
terrain classes to learn drivable surfaces and natural obstacles in outdoor
scenes effectively. We evaluate the performance of modern semantic segmentation
models with an additional focus on their efficiency. Our experiments
demonstrate the advantages of fine-grained semantic classes to improve the
overall prediction accuracy, especially along the class boundaries. The dataset
and pretrained model are available at mucar3.de/icpr2020-tas500.Comment: Accepted at International Conference on Pattern Recognition 2020
(ICPR). For the associated project page, see
https://www.mucar3.de/icpr2020-tas500/index.htm
Games as Systems for Rehabilitation: A Design Strategy for Game-based Exercise Rehabilitation for Parkinson\u27s Disease
Games are of interest for health interventions including but not limited to physical activity and rehabilitation, behavior change, motor-cognitive training, and mood elevation. Despite increased interest in using games to produce positive health outcomes, the development or selection process of games, or their suitability for a target demographic in a context of health and rehabilitation, remains ad-hoc. As a result, game-based interventions lacking application specificity produce variable outcomes that obscure the true treatment effect of game-based therapies. To address this issue, we present a design strategy for game-based rehabilitation that uses a player-centric approach to develop/select games for specific contexts such as for improving functional deficits in patients with Parkinson’s disease. This strategy establishes a relationship between the exercise rehabilitation regimen and gameplay by incorporating the rehabilitation requirements, patient condition, and player affordances, into the game world. In addition, we present guiding questions to support the application of the design strategy for improving the effectiveness of game-based rehabilitations
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