11,343 research outputs found
An L1 image transform for edge-preserving smoothing and scene-level intrinsic decomposition
Identifying sparse salient structures from dense pixels is a longstanding problem in visual computing. Solutions to this problem can benefit both image manipulation and understanding. In this paper, we introduce an image transform based on the L1 norm for piecewise image flattening. This transform can effectively preserve and sharpen salient edges and contours while eliminating insignificant details, producing a nearly piecewise constant image with sparse structures. A variant of this image transform can perform edge-preserving smoothing more effectively than existing state-of-the-art algorithms. We further present a new method for complex scene-level intrinsic image decomposition. Our method relies on the above image transform to suppress surface shading variations, and perform probabilistic reflectance clustering on the flattened image instead of the original input image to achieve higher accuracy. Extensive testing on the Intrinsic-Images-in-the-Wild database indicates our method can perform significantly better than existing techniques both visually and numerically. The obtained intrinsic images have been successfully used in two applications, surface retexturing and 3D object compositing in photographs.postprin
Polycyclic Aromatic Hydrocarbons and Polychlorinated Biphenyl Contamination in DaTong City, China
CP Asymmetry in Charged Higgs Decays in MSSM
We discuss and compare the charge-parity (CP) asymmetry in the charged Higgs
boson decays H -> \bar{u}_i d_j for the second and third generation quarks in
the minimal supersymmetric standard model. As part of the analysis, we derive
some general analytical formulas for the imaginary parts of two-point and
three-point scalar one-loop integrals and use them for calculating vectorial
and tensorial type integrals needed for the problem under consideration. We
find that, even though each decay mode has a potential to yield a CP asymmetry
larger than 10%, further analysis based on the number of required charged Higgs
events at colliders favors the \bar{t}b, \bar{c}b, and \bar{c}s channels, whose
asymmetry could reach 10-15% in certain parts of the parameter space.Comment: 25 pages, 9 figures. Discussion about charged Higgs observability
added, typos corrected, accepted for publication in PR
Local effects of climate change over the Alpine region: A study with a high resolution regional climate model with a surrogate climate change scenario
We discuss a surrogate climate change (SCC) simulation over the Alpine region with a high resolution regional climate model (RegCM3) using a fine scale subâgrid land surface representation. Multiâyear simulations are completed with an imposed illustrative 3K warming on the forcing large scale meteorological conditions and on the sea surface temperatures in the interior domain. The corresponding relative humidity is kept constant, which results in an increase of atmospheric moisture. We find that in the winter season precipitation increases consistently with the SCC approach, with a significant dependence on topographical elevation. Other components of the surface energy and water budgets also show a marked elevation dependency, mostly tied to changes in snow cover. In summer, contrary to what might be expected from the SCC forcing, precipitation decreases over the Alpine mountain chain. This is due to a local surfaceâatmosphere feedback mechanism involving reduced snow cover and soil moisture at the beginning of summer. Our results suggest that over the Alps during summer local feedbacks related to the surface energy and water budgets are important factors in determining the precipitation response to global warming. This result might extend to other midâlatitude mountainous areas
Validation of a High-Resolution Regional Climate Model for the Alpine Region and Effects of a Subgrid-Scale Topography and Land Use Representation
n/
The Impact of Word, Multiple Word, and Sentence Input on Virtual Keyboard Decoding Performance
Entering text on non-desktop computing devices is often done
via an onscreen virtual keyboard. Input on such keyboards
normally consists of a sequence of noisy tap events that specify
some amount of text, most commonly a single word. But
is single word-at-a-time entry the best choice? This paper
compares user performance and recognition accuracy of wordat-
a-time, phrase-at-a-time, and sentence-at-a-time text entry
on a smartwatch keyboard. We evaluate the impact of differing
amounts of input in both text copy and free composition tasks.
We found providing input of an entire sentence significantly
improved entry rates from 26wpm to 32wpm while keeping
character error rates below 4%. In offline experiments with
more processing power and memory, sentence input was recognized
with a much lower 2.0% error rate. Our findings suggest
virtual keyboards can enhance performance by encouraging
users to provide more input per recognition event.This work was supported by Google Faculty awards (K.V. and
P.O.K.
Infrared response of ordered polarons in layered perovskites
We report on the infrared absorption spectra of three oxides where charged
superlattices have been recently observed in diffraction experiments. In
LaSrNiO, polaron localization is found to suppress the
low-energy conductivity through the opening of a gap and to split the
- vibrational manifold of the oxygen octahedra. Similar effects
are detected in SrLaMnO and in LaNiO, with
peculiar differences related to the type of charge ordering.Comment: File latex, 11 p. + 3 Figures, to appear on Phys. Rev. B (Rapid
Commun.), 1 Oct. 1996. The figures will be faxed upon request.
E-mail:[email protected] Fax: +39-6-446315
Exploring user-generated content related to vegetarian customers in restaurants: an analysis of online reviews
The purpose of this research is to explore and evaluate factors that impact the dining experience of vegetarian consumers within a range of vegetarian-friendly restaurants. To explore the factors and understand consumer experience, this study analyzes a vast number of user-generated contents of vegetarian consumers which have become vital sources of consumer experience information. This study utilizes machine learning techniques and traditional methods to examine 54,299 TripAdvisor reviews of approximately 1,008 vegetarian-friendly restaurants in London. The study identifies 20 topics that represent a holistic opinion influencing the dining experience of vegetarian customers. The results suggest that âfriendly staffâ is the most popular topic, and has the highest topic percentage. The results of regression analyses reveal that six topics have a significant impact on restaurant ratings, while thirteen topics have negative impacts. Restaurant managers who pay close attention to vegetarian aspects may utilize the findings of this paper to better satisfy vegetarian consumer demands and formulate appropriate training courses
Ages and Masses of 0.64 million Red Giant Branch stars from the LAMOST Galactic Spectroscopic Survey
We present a catalog of stellar age and mass estimates for a sample of
640\,986 red giant branch (RGB) stars of the Galactic disk from the LAMOST
Galactic Spectroscopic Survey (DR4). The RGB stars are distinguished from the
red clump stars utilizing period spacing derived from the spectra with a
machine learning method based on kernel principal component analysis (KPCA).
Cross-validation suggests our method is capable of distinguishing RC from RGB
stars with only 2 per cent contamination rate for stars with signal-to-noise
ratio (SNR) higher than 50. The age and mass of these RGB stars are determined
from their LAMOST spectra with KPCA method by taking the LAMOST -
giant stars having asteroseismic parameters and the LAMOST-TGAS sub-giant stars
based on isochrones as training sets. Examinations suggest that the age and
mass estimates of our RGB sample stars with SNR 30 have a median error of
30 per cent and 10 per cent, respectively. Stellar ages are found to exhibit
positive vertical and negative radial gradients across the disk, and the age
structure of the disk is strongly flared across the whole disk of
\,kpc. The data set demonstrates good correlations among stellar age,
[Fe/H] and [/Fe]. There are two separate sequences in the [Fe/H] --
[/Fe] plane: a high-- sequence with stars older than
\,8\,Gyr and a low-- sequence composed of stars with ages
covering the whole range of possible ages of stars. We also examine relations
between age and kinematic parameters derived from the Gaia DR2 parallax and
proper motions. Both the median value and dispersion of the orbital
eccentricity are found to increase with age. The vertical angular momentum is
found to fairly smoothly decrease with age from 2 to 12\,Gyr, with a rate of
about 50\,kpc\,km\,s\,Gyr. A full table of the catalog is
public available online.Comment: 16 pages, 22 figures,accepted by MNRA
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