320 research outputs found
CrossData: Leveraging Text-Data Connections for Authoring Data Documents
Data documents play a central role in recording, presenting, and
disseminating data. Despite the proliferation of applications and systems
designed to support the analysis, visualization, and communication of data,
writing data documents remains a laborious process, requiring a constant
back-and-forth between data processing and writing tools. Interviews with eight
professionals revealed that their workflows contained numerous tedious,
repetitive, and error-prone operations. The key issue that we identified is the
lack of persistent connection between text and data. Thus, we developed
CrossData, a prototype that treats text-data connections as persistent,
interactive, first-class objects. By automatically identifying, establishing,
and leveraging text-data connections, CrossData enables rich interactions to
assist in the authoring of data documents. An expert evaluation with eight
users demonstrated the usefulness of CrossData, showing that it not only
reduced the manual effort in writing data documents but also opened new
possibilities to bridge the gap between data exploration and writing
1-[(1,3-Dithiolan-2-yl)methyl]-6-methyl-8-nitro-1,2,3,5,6,7-hexahydroimidazo[1,2-c]pyrimidine
In the title compound, C11H18N4O2S2, the dithiolane ring displays an envelope conformation, the tetrahydropyrimidine ring has a conformation that is between half-chair and screw-boat, and the imidazole ring is essentially planar (r.m.s. deviation = 0.0017 Å). No significant directional intermolecular interactions are present in the structure
A novel approach for estimation of above-ground biomass of sugar beet based on wavelength selection and optimized support vector machine
Timely diagnosis of sugar beet above-ground biomass (AGB) is critical for the prediction of yield and optimal precision crop management. This study established an optimal quantitative prediction model of AGB of sugar beet by using hyperspectral data. Three experiment campaigns in 2014, 2015 and 2018 were conducted to collect ground-based hyperspectral data at three different growth stages, across different sites, for different cultivars and nitrogen (N) application rates. A competitive adaptive reweighted sampling (CARS) algorithm was applied to select the most sensitive wavelengths to AGB. This was followed by developing a novel modified differential evolution grey wolf optimization algorithm (MDE-GWO) by introducing differential evolution algorithm (DE) and dynamic non-linear convergence factor to grey wolf optimization algorithm (GWO) to optimize the parameters c and gamma of a support vector machine (SVM) model for the prediction of AGB. The prediction performance of SVM models under the three GWO, DE-GWO and MDE-GWO optimization methods for CARS selected wavelengths and whole spectral data was examined. Results showed that CARS resulted in a huge wavelength reduction of 97.4% for the rapid growth stage of leaf cluster, 97.2% for the sugar growth stage and 97.4% for the sugar accumulation stage. Models resulted after CARS wavelength selection were found to be more accurate than models developed using the entire spectral data. The best prediction accuracy was achieved after the MDE-GWO optimization of SVM model parameters for the prediction of AGB in sugar beet, independent of growing stage, years, sites and cultivars. The best coefficient of determination (R-2), root mean square error (RMSE) and residual prediction deviation (RPD) ranged, respectively, from 0.74 to 0.80, 46.17 to 65.68 g/m(2) and 1.42 to 1.97 for the rapid growth stage of leaf cluster, 0.78 to 0.80, 30.16 to 37.03 g/m(2) and 1.69 to 2.03 for the sugar growth stage, and 0.69 to 0.74, 40.17 to 104.08 g/m(2) and 1.61 to 1.95 for the sugar accumulation stage. It can be concluded that the methodology proposed can be implemented for the prediction of AGB of sugar beet using proximal hyperspectral sensors under a wide range of environmental conditions
1-[(1,3-Dithiolan-2-yl)methyl]-8-nitro-6-propyl-1,2,3,5,6,7-hexahydroimidazo[1,2-c]pyrimidine
In the title compound, C13H22N4O2S2, the six-membered ring displays a half-chair conformation. The olefin amine unit is close to being coplanar with the imidazolidine ring (r.m.s. deviation = 0.059 Å). The dithiolane ring adopts a twisted conformation. In the crystal, molecules are linked by weak C—H⋯O interactions
Calibration of metallicity of LAMOST M dwarf stars Using FGK+M wide binaries
Estimating precise metallicity of M dwarfs is a well-known difficult problem
due to their complex spectra. In this work, we empirically calibrate the
metallicity using wide binaries with a F, G, or K dwarf and a M dwarf
companion. With 1308 FGK+M wide binaries well observed by LAMOST, we calibrated
M dwarf's [Fe/H] by using the Stellar LAbel Machine (SLAM) model, a data-driven
method based on support vector regression (SVR). The [Fe/H] labels of the
training data are from FGK companions in range of [-1,0.5] dex. The Teffs are
selected from Li et al. (2021), spanning [3100,4400] K. The uncertainties in
SLAM estimates of [Fe/H] and Teff are ~0.15 dex and ~40 K, respectively, at
snri > 100, where snri is the signal-to-noise ratio (SNR) at i-band of M dwarf
spectra. We applied the trained SLAM model to determine the [Fe/H] and Teff for
~630,000 M dwarfs with low-resolution spectra in LAMOST DR9. Compared to other
literature also using FGK+M wide binaries for calibration, our [Fe/H] estimates
show no bias but a scatter of ~ 0.14-0.18 dex. However, the [Fe/H] compared to
APOGEE shows a systematic difference of ~ 0.10-0.15 dex with a scatter of ~
0.15-0.20 dex. While the Teff compared to APOGEE has a bias of 3 K with a
scatter of 62 K, it is systematically higher by 180 K compared to other
calibrations based on the bolometric temperature. Finally, we calculated the
zeta index for 1308 M dwarf secondaries and presents a moderate correlation
between zeta and [Fe/H].Comment: 18 pages, 15 Figure
Discovery of an equal-mass "twin" binary population reaching 1000+ AU separations
We use a homogeneous catalog of 42,000 main-sequence wide binaries identified
by Gaia to measure the mass ratio distribution, p(q), of binaries with primary
masses , mass ratios , and separations
. A well-understood selection function allows us to
constrain p(q) in 35 independent bins of primary mass and separation, with
hundreds to thousands of binaries in each bin. Our investigation reveals a
sharp excess of equal-mass "twin" binaries that is statistically significant
out to separations of 1,000 to 10,000 AU, depending on primary mass. The excess
is narrow: a steep increase in p(q) at , with no significant
excess at . A range of tests confirm the signal is real, not a
data artifact or selection effect. Combining the Gaia constraints with those
from close binaries, we show that the twin excess decreases with increasing
separation, but its width () is constant over . The wide twin population would be difficult to explain if the
components of all wide binaries formed via core fragmentation, which is not
expected to produce strongly correlated component masses. We conjecture that
wide twins formed at closer separations ( AU), likely via
accretion from circumbinary disks, and were subsequently widened by dynamical
interactions in their birth environments. The separation-dependence of the twin
excess then constrains the efficiency of dynamical widening and disruption of
binaries in young clusters. We also constrain p(q) across .
Besides changes in the twin fraction, p(q) is independent of separation at
fixed primary mass over . It is flatter than
expected for random pairings from the IMF but more bottom-heavy for wide
binaries than for binaries with 100 AU.Comment: 24 pages, 17 figures, plus appendices. Accepted to MNRAS. Fig 17 and
Appendix F are new since v
iBall: Augmenting Basketball Videos with Gaze-moderated Embedded Visualizations
We present iBall, a basketball video-watching system that leverages
gaze-moderated embedded visualizations to facilitate game understanding and
engagement of casual fans. Video broadcasting and online video platforms make
watching basketball games increasingly accessible. Yet, for new or casual fans,
watching basketball videos is often confusing due to their limited basketball
knowledge and the lack of accessible, on-demand information to resolve their
confusion. To assist casual fans in watching basketball videos, we compared the
game-watching behaviors of casual and die-hard fans in a formative study and
developed iBall based on the fndings. iBall embeds visualizations into
basketball videos using a computer vision pipeline, and automatically adapts
the visualizations based on the game context and users' gaze, helping casual
fans appreciate basketball games without being overwhelmed. We confrmed the
usefulness, usability, and engagement of iBall in a study with 16 casual fans,
and further collected feedback from 8 die-hard fans.Comment: ACM CHI2
Early Triassic wrinkle structures on land:stressed environments and oases for life
Wrinkle structures in rocks younger than the Permian-Triassic (P-Tr) extinction have been reported repeatedly in marine strata, but rarely mentioned in rocks recording land. Here, three newly studied terrestrial P-Tr boundary rock succession in North China have yielded diverse wrinkle structures. All of these wrinkles are preserved in barely bioturbated shore-shallow lacustrine siliciclastic deposits of the Liujiagou Formation. Conversely, both the lacustrine siliciclastic deposits of the underlying Sunjiagou Formation and the overlying Heshanggou Formation show rich bioturbation, but no wrinkle structures or other microbial-related structures. The occurrence of terrestrial wrinkle structures in the studied sections reflects abnormal hydrochemical and physical environments, presumably associated with the extinction of terrestrial organisms. Only very rare trace fossils occurred in the aftermath of the P-Tr extinction, but most of them were preserved together with the microbial mats. This suggests that microbial mats acted as potential oases for the surviving aquatic animals, as a source of food and oxygen. The new finds suggests that extreme environmental stresses were prevalent both in the sea and on land through most of the Early Triassic
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