10,285 research outputs found
Predictive Inference for Spatio-temporal Precipitation Data and Its Extremes
Modelling of precipitation and its extremes is important for urban and
agriculture planning purposes. We present a method for producing spatial
predictions and measures of uncertainty for spatio-temporal data that is
heavy-tailed and subject to substaintial skewness which often arise in
measurements of many environmental processes, and we apply the method to
precipitation data in south-west Western Australia. A generalised hyperbolic
Bayesian hierarchical model is constructed for the intensity, frequency and
duration of daily precipitation, including the extremes. Unlike models based on
extreme value theory, which only model maxima of finite-sized blocks or
exceedances above a large threshold, the proposed model uses all the data
available efficiently, and hence not only fits the extremes but also models the
entire rainfall distribution. It captures spatial and temporal clustering, as
well as spatially and temporally varying volatility and skewness. The model
assumes that the regional precipitation is driven by a latent process
characterised by geographical and climatological covariates. Effects not fully
described by the covariates are captured by spatial and temporal structure in
the hierarchies. Inference is provided by MCMC using a Metropolis-Hastings
algorithm and spatial interpolation method, which provide a natural approach
for estimating uncertainty. Similarly both spatial and temporal predictions
with uncertainty can be produced with the model.Comment: Under review at Journal of the American Statistical Association. 27
pages, 10 figure
Approximation learning methods of Harmonic Mappings in relation to Hardy Spaces
A new Hardy space Hardy space approach of Dirichlet type problem based on
Tikhonov regularization and Reproducing Hilbert kernel space is discussed in
this paper, which turns out to be a typical extremal problem located on the
upper upper-high complex plane. If considering this in the Hardy space, the
optimization operator of this problem will be highly simplified and an
efficient algorithm is possible. This is mainly realized by the help of
reproducing properties of the functions in the Hardy space of upper-high
complex plane, and the detail algorithm is proposed. Moreover, harmonic
mappings, which is a significant geometric transformation, are commonly used in
many applications such as image processing, since it describes the energy
minimization mappings between individual manifolds. Particularly, when we focus
on the planer mappings between two Euclid planer regions, the harmonic mappings
are exist and unique, which is guaranteed solidly by the existence of harmonic
function. This property is attractive and simulation results are shown in this
paper to ensure the capability of applications such as planer shape distortion
and surface registration.Comment: 2016 3rd International Conference on Informative and Cybernetics for
Computational Social Systems (ICCSS
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An exploratory study of imagining sounds and āhearingā music in autism
Individuals with autism spectrum disorder (ASD) reportedly possess preserved or superior music-processing skills compared to their typically developing counterparts. We examined auditory imagery and earworms (tunes that get āstuckā in the head) in adults with ASD and controls. Both groups completed a short earworm questionnaire together with the Bucknell Auditory Imagery Scale. Results showed poorer auditory imagery in the ASD group for all types of auditory imagery. However, the ASD group did not report fewer earworms than matched controls. These data suggest a possible basis in poor auditory imagery for poor prosody in ASD, but also highlight a separability between auditory imagery and control of musical memories. The separability is present in the ASD group but not in typically developing individuals
Creating Simplified 3D Models with High Quality Textures
This paper presents an extension to the KinectFusion algorithm which allows
creating simplified 3D models with high quality RGB textures. This is achieved
through (i) creating model textures using images from an HD RGB camera that is
calibrated with Kinect depth camera, (ii) using a modified scheme to update
model textures in an asymmetrical colour volume that contains a higher number
of voxels than that of the geometry volume, (iii) simplifying dense polygon
mesh model using quadric-based mesh decimation algorithm, and (iv) creating and
mapping 2D textures to every polygon in the output 3D model. The proposed
method is implemented in real-time by means of GPU parallel processing.
Visualization via ray casting of both geometry and colour volumes provides
users with a real-time feedback of the currently scanned 3D model. Experimental
results show that the proposed method is capable of keeping the model texture
quality even for a heavily decimated model and that, when reconstructing small
objects, photorealistic RGB textures can still be reconstructed.Comment: 2015 International Conference on Digital Image Computing: Techniques
and Applications (DICTA), Page 1 -
GaAs-based subwavelength grating on an AlOx layer for a vertical-cavity surface-emitting laser
Ā© 2020 Optical Society of America. Users may use, reuse, and build upon the article, or use the article for text or data mining, so long as such uses are for non-commercial purposes and appropriate attribution is maintained. All other rights are reserved.A GaAs-based subwavelength grating on a thick (ā¼3/4*Ī» at 1300 nm) AlOx layer is designed, fabricated, and characterized. The AlOx layer as a low-index medium is oxidized from a 640-nm Al0.9Ga0.1As layer. The layer contraction of the Al0.9Ga0.1As layer after wet oxidation to AlOx is 4.9%. We fabricated GaAs-based subwavelength gratings on the AlOx layer showing a high reflectivity of 90% in the 1300-nm wavelength range, consistent with the simulation results. Such GaAs-based subwavelength gratings can be used as high-contrast grating mirrors for narrow-linewidth VCSELs, improving the mechanical stability and simplifying the device fabrication
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