126 research outputs found
TMR: Text-to-Motion Retrieval Using Contrastive 3D Human Motion Synthesis
In this paper, we present TMR, a simple yet effective approach for text to 3D
human motion retrieval. While previous work has only treated retrieval as a
proxy evaluation metric, we tackle it as a standalone task. Our method extends
the state-of-the-art text-to-motion synthesis model TEMOS, and incorporates a
contrastive loss to better structure the cross-modal latent space. We show that
maintaining the motion generation loss, along with the contrastive training, is
crucial to obtain good performance. We introduce a benchmark for evaluation and
provide an in-depth analysis by reporting results on several protocols. Our
extensive experiments on the KIT-ML and HumanML3D datasets show that TMR
outperforms the prior work by a significant margin, for example reducing the
median rank from 54 to 19. Finally, we showcase the potential of our approach
on moment retrieval. Our code and models are publicly available.Comment: arXiv preprint, project page: https://mathis.petrovich.fr/tmr
SINC: Spatial Composition of 3D Human Motions for Simultaneous Action Generation
Our goal is to synthesize 3D human motions given textual inputs describing
simultaneous actions, for example 'waving hand' while 'walking' at the same
time. We refer to generating such simultaneous movements as performing 'spatial
compositions'. In contrast to temporal compositions that seek to transition
from one action to another, spatial compositing requires understanding which
body parts are involved in which action, to be able to move them
simultaneously. Motivated by the observation that the correspondence between
actions and body parts is encoded in powerful language models, we extract this
knowledge by prompting GPT-3 with text such as "what are the body parts
involved in the action ?", while also providing the parts list and
few-shot examples. Given this action-part mapping, we combine body parts from
two motions together and establish the first automated method to spatially
compose two actions. However, training data with compositional actions is
always limited by the combinatorics. Hence, we further create synthetic data
with this approach, and use it to train a new state-of-the-art text-to-motion
generation model, called SINC ("SImultaneous actioN Compositions for 3D human
motions"). In our experiments, that training with such GPT-guided synthetic
data improves spatial composition generation over baselines. Our code is
publicly available at https://sinc.is.tue.mpg.de/.Comment: ICCV 2023 Camera Read
NEID Reveals that The Young Warm Neptune TOI-2076 b Has a Low Obliquity
TOI-2076 b is a sub-Neptune-sized planet () that transits a young () bright
() K-dwarf hosting a system of three transiting planets. Using
spectroscopic observations with the NEID spectrograph on the WIYN 3.5 m
Telescope, we model the Rossiter-McLaughlin effect of TOI-2076 b, and derive a
sky-projected obliquity of . Using the size of
the star (), and the stellar rotation period
( days), we estimate a true obliquity of
( at 95% confidence),
demonstrating that TOI-2076 b is on a well-aligned orbit. Simultaneous
diffuser-assisted photometry from the 3.5 m Telescope at Apache Point
Observatory rules out flares during the transit. TOI-2076 b joins a small but
growing sample of young planets in compact multi-planet systems with
well-aligned orbits, and is the fourth planet with an age Myr in
a multi-transiting system with an obliquity measurement. The low obliquity of
TOI-2076 b and the presence of transit timing variations in the system suggest
the TOI-2076 system likely formed via convergent disk migration in an initially
well-aligned disk.Comment: Submitted to ApJL, 13 pages, 4 figures, 3 table
Light meson spectroscopy from Dalitz plot analyses of ηc decays to η0 K+K− , η0 π + π − , and ηπ + π − produced in two-photon interactions
We study the processes γγ→ηc→η′K+K−, η′π+π−, and ηπ+π− using a data sample of 519  fb−1 recorded with the BABAR detector operating at the SLAC PEP-II asymmetric-energy e+e− collider at center-of-mass energies at and near the Υ(nS) (n=2, 3, 4) resonances. This is the first observation of the decay ηc→η′K+K− and we measure the branching fraction Γ(ηc→η′K+K−)/(Γ(ηc→η′π+π−)=0.644±0.039stat±0.032sys. Significant interference is observed between γγ→ηc→ηπ+π− and the nonresonant two-photon process γγ→ηπ+π−. A Dalitz plot analysis is performed of ηc decays to η′K+K−, η′π+π−, and ηπ+π−. Combined with our previous analysis of ηc→K¯Kπ, we measure the K∗0(1430) parameters and the ratio between its η′K and πK couplings. The decay ηc→η′π+π− is dominated by the f0(2100) resonance, also observed in J/ψ radiative decays. A new a0(1700)→ηπ resonance is observed in the ηc→ηπ+π− channel. We also compare ηc decays to η and η′ final states in association with scalar mesons as they relate to the identification of the scalar glueball.publishedVersio
Search for rare or forbidden decays of the D0 meson
We present a search for nine lepton-number-violating and three lepton-flavor-violating neutral charm decays of the type D0→h'−h−ℓ'+ℓ+ and D0→h'−h+ℓ'±ℓ∓, where h and h′ represent a K or π meson and ℓ and ℓ′ an electron or muon. The analysis is based on 468 fb−1 of e+e− annihilation data collected at or close to the Υ(4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory. No significant signal is observed for any of the twelve modes, and we establish 90% confidence level upper limits on the branching fractions in the range (1.0–30.6)×10−7. The limits are between 1 and 3 orders of magnitude more stringent than previous measurements.publishedVersio
Measurements of the absolute branching fractions of B± →k±Xc c
A study of the two-body decays B±→Xc¯cK±, where Xc¯c refers to one charmonium state, is reported by the BABAR Collaboration using a data sample of 424 fb−1. The absolute determination of branching fractions for these decays are significantly improved compared to previous BABAR measurements. Evidence is found for the decay B+→X(3872)K+ at the 3σ level. The absolute branching fraction B[B+→X(3872)K+]=[2.1±0.6(stat)±0.3(syst)]×10−4 is measured for the first time. It follows that B[X(3872)→J/ψπ+π−]=(4.1±1.3)%, supporting the hypothesis of a molecular component for this resonance.publishedVersio
An ultrahot Neptune in the Neptune desert
About 1 out of 200 Sun-like stars has a planet with an orbital period shorter than one day: an ultrashort-period planet. All of the previously known ultrashort-period planets are either hot Jupiters, with sizes above 10 Earth radii (R⊕), or apparently rocky planets smaller than 2 R⊕. Such lack of planets of intermediate size (the ‘hot Neptune desert’) has been interpreted as the inability of low-mass planets to retain any hydrogen/helium (H/He) envelope in the face of strong stellar irradiation. Here we report the discovery of an ultrashort-period planet with a radius of 4.6 R⊕ and a mass of 29 M⊕, firmly in the hot Neptune desert. Data from the Transiting Exoplanet Survey Satellite revealed transits of the bright Sun-like star LTT 9779 every 0.79 days. The planet’s mean density is similar to that of Neptune, and according to thermal evolution models, it has a H/He-rich envelope constituting 9.0^(+2.7)_(−2.9)% of the total mass. With an equilibrium temperature around 2,000 K, it is unclear how this ‘ultrahot Neptune’ managed to retain such an envelope. Follow-up observations of the planet’s atmosphere to better understand its origin and physical nature will be facilitated by the star’s brightness (V_(mag) = 9.8)
The global burden of injury: Incidence, mortality, disability-adjusted life years and time trends from the global burden of disease study 2013
Background The Global Burden of Diseases (GBD), Injuries, and Risk Factors study used the disabilityadjusted life year (DALY) to quantify the burden of diseases, injuries, and risk factors. This paper provides an overview of injury estimates from the 2013 update of GBD, with detailed information on incidence, mortality, DALYs and rates of change from 1990 to 2013 for 26 causes of injury, globally, by region and by country. Methods Injury mortality was estimated using the extensive GBD mortality database, corrections for illdefined cause of death and the cause of death ensemble modelling tool. Morbidity estimation was based on inpatient and outpatient data sets, 26 cause-of-injury and 47 nature-of-injury categories, and seven follow-up studies with patient-reported long-term outcome measures. Results In 2013, 973 million (uncertainty interval (UI) 942 to 993) people sustained injuries that warranted some type of healthcare and 4.8 million (UI 4.5 to 5.1) people died from injuries. Between 1990 and 2013 the global age-standardised injury DALY rate decreased by 31% (UI 26% to 35%). The rate of decline in DALY rates was significant for 22 cause-of-injury categories, including all the major injuries. Conclusions Injuries continue to be an important cause of morbidity and mortality in the developed and developing world. The decline in rates for almost all injuries is so prominent that it warrants a general statement that the world is becoming a safer place to live in. However, the patterns vary widely by cause, age, sex, region and time and there are still large improvements that need to be made
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