181,354 research outputs found
Learning Latent Super-Events to Detect Multiple Activities in Videos
In this paper, we introduce the concept of learning latent super-events from
activity videos, and present how it benefits activity detection in continuous
videos. We define a super-event as a set of multiple events occurring together
in videos with a particular temporal organization; it is the opposite concept
of sub-events. Real-world videos contain multiple activities and are rarely
segmented (e.g., surveillance videos), and learning latent super-events allows
the model to capture how the events are temporally related in videos. We design
temporal structure filters that enable the model to focus on particular
sub-intervals of the videos, and use them together with a soft attention
mechanism to learn representations of latent super-events. Super-event
representations are combined with per-frame or per-segment CNNs to provide
frame-level annotations. Our approach is designed to be fully differentiable,
enabling end-to-end learning of latent super-event representations jointly with
the activity detector using them. Our experiments with multiple public video
datasets confirm that the proposed concept of latent super-event learning
significantly benefits activity detection, advancing the state-of-the-arts.Comment: CVPR 201
Isolation and characterisation of 2-Tert-butyl-8-hydroxyquinoline as a crystalline solid and its blue fluorescent Li complex
Copyright © 2014 Poopathy Kathirgamanathan et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.2-Tert-butyl-8-hydroxyquinoline (2-TB-8-hq) has been isolated as a crystalline solid and its X-ray structure elucidated, resolving three decades of controversy, since it was previously wrongly reported as yellow oil by some other workers. An improved synthetic method has been developed which increases the yield from 20% to 60%. The lithium complex of 2-TB-8-hq is blue emitting and the HOMO and LUMO levels are lowered by 0.86 eV and 0.74 eV, respectively, compared with the parent lithium 8-hydroxyquinolinolate (Li 8-hq)
Completing NLO QCD Corrections for Tree Level Non-Leptonic Delta F = 1 Decays Beyond the Standard Model
In various extensions of the Standard Model (SM) tree level non-leptonic
decays of hadrons receive contributions from new heavy gauge bosons and
scalars. Prominent examples are the right-handed W' bosons in left-right
symmetric models and charged Higgs (H^\pm) particles in models with extended
scalar sector like two Higgs doublet models and supersymmetric models. Even in
the case of decays with four different quark flavours involved, to which
penguin operators cannot contribute, twenty linearly independent operators,
instead of two in the SM, have to be considered. Anticipating the important
role of such decays at the LHCb, KEKB and Super-B in Rome and having in mind
future improved lattice computations, we complete the existing NLO QCD formulae
for these processes by calculating O(alpha_s) corrections to matching
conditions for the Wilson coefficients of all contributing operators in the
NDR-\bar{MS} scheme. This allows to reduce certain unphysical scale and
renormalization scheme dependences in the existing NLO calculations. Our
results can also be applied to models with tree-level heavy neutral gauge boson
and scalar exchanges in Delta F = 1 transitions and constitute an important
part of NLO analyses of those non-leptonic decays to which also penguin
operators contribute.Comment: 24 pages, 6 figure
Periodic letter strokes within a word affect fixation disparity during reading
We investigated the way in which binocular coordination in reading is affected by the spatial structure of text. Vergence eye movements were measured (EyeLink II) in 32 observers while they read 120 single German sentences (Potsdam Sentence Corpus) silently for comprehension. The similarity in shape between the neighboring strokes of component letters, as measured by the first peak in the horizontal auto-correlation of the images of the words, was found to be associated with (i) a smaller minimum fixation disparity (i.e. vergence error) during fixation; (ii) a longer time to reach this minimum disparity and (iii) a longer overall fixation duration. The results were obtained only for binocular reading: no effects of auto-correlation could be observed for monocular reading. The findings help to explain the longer reading times reported for words and fonts with high auto-correlation and may also begin to provide a causal link between poor binocular control and reading difficulties. © ARVO
THE ROLE OF PREVIOUS ANTERIOR CRUCIATE LIGAMENT INJURY ON THE VARIABILITY OF JOINT KINEMATICS AND COORDINATION DURING A MATCH SPECIFIC LAND-CUT TASK
This study compared the movement and coordination variability of the previously injured leg of ACL injured subjects (ACLr, n=9), against their non-injured leg and a control (nACL, n=9) leg. The variability of lower limb joint angles and couplings were calculated during a land-cut task (n=20). The previously injured leg had less variability than the noninjured leg in the knee rotation–knee abd-adduction coupling, and more variability than the nACL leg in frontal and transverse knee joint angles and hip rotation–knee abdadduction coupling. Reduced coordination variability could produce a more repetitive loading pattern linked to cartilage degeneration. Increased movement and coordination variability may stem from proprioceptive deficits on the previously injured leg and decrease the ability to adapt to perturbations
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