3,622 research outputs found
Deep Adaptive Attention for Joint Facial Action Unit Detection and Face Alignment
Facial action unit (AU) detection and face alignment are two highly
correlated tasks since facial landmarks can provide precise AU locations to
facilitate the extraction of meaningful local features for AU detection. Most
existing AU detection works often treat face alignment as a preprocessing and
handle the two tasks independently. In this paper, we propose a novel
end-to-end deep learning framework for joint AU detection and face alignment,
which has not been explored before. In particular, multi-scale shared features
are learned firstly, and high-level features of face alignment are fed into AU
detection. Moreover, to extract precise local features, we propose an adaptive
attention learning module to refine the attention map of each AU adaptively.
Finally, the assembled local features are integrated with face alignment
features and global features for AU detection. Experiments on BP4D and DISFA
benchmarks demonstrate that our framework significantly outperforms the
state-of-the-art methods for AU detection.Comment: This paper has been accepted by ECCV 201
Angle Domain Signal Processing-Aided Channel Estimation for Indoor 60-GHz TDD/FDD Massive MIMO Systems
Polarization evolution accompanying the very early sharp decline of GRB X-ray afterglows
In the synchrotron radiation model, the polarization property depends on both
the configuration of the magnetic field and the geometry of the visible
emitting region. Some peculiar behaviors in the X-ray afterglows of {\it Swift}
gamma-ray bursts (GRBs), such as energetic flares and the plateau followed by a
sharp drop, might by highly linearly-polarized because the outflows powering
these behaviors may be Poynting-flux dominated. Furthermore, the broken-down of
the symmetry of the visible emitting region may be hiding in current X-ray data
and will give rise to interesting polarization signatures. In this work we
focus on the polarization accompanying the very early sharp decline of GRB
X-ray afterglows. We show that strong polarization evolution is possible in
both the high latitude emission model and the dying central engine model which
are used to interpret this sharp X-ray decline. It is thus not easy to
efficiently probe the physical origin of the very early X-ray sharp decline
with future polarimetry. Strong polarization evolution is also possible in the
decline phase of X-ray flares and in the shallow decline phase of X-ray light
curves characterized by chromatic X-ray VS. Optical breaks. An {\it XRT}-like
detector but with polarization capability on board a {\em Swift}-like satellite
would be suitable to test our predictions.Comment: 9 pages including 4 figures. Accepted for publication in MNRAS, typos
correcte
Formation of coupled three-dimensional GeSi quantum dot crystals
Coupled three-dimensional GeSi quantum dot crystals (QDCs) are realized by multilayer growth of quantum dots (QDs) on patterned SOI (001) substrates. Photoluminescence spectra of these QDCs show non-phonon (NP) recombination and its transverse-optical (TO) phonon replica of excitons in QDs. With increasing excitation power, peak energies of both the NP and TO peaks remain nearly constant and the width of the TO peak decreases. These anomalous features of the PL peaks are attributed to miniband formation due to strong coupling of the holes and the emergence of quasioptical phonon modes due to periodic scatters in ordered GeSi QDs
Neurologic Abnormalities in Workers of a 1-Bromopropane Factory
We reported recently that 1-bromopropane (1-BP; n-propylbromide, CAS Registry no. 106-94-5), an alternative to ozone-depleting solvents, is neurotoxic and exhibits reproductive toxicity in rats. The four most recent case reports suggested possible neurotoxicity of 1-BP in workers. The aim of the present study was to establish the neurologic effects of 1-BP in workers and examine the relationship with exposure levels. We surveyed 27 female workers in a 1-BP production factory and compared 23 of them with 23 age-matched workers in a beer factory as controls. The workers were interviewed and examined by neurologic, electrophysiologic, hematologic, biochemical, neurobehavioral, and postural sway tests. 1-BP exposure levels were estimated with passive samplers. Tests with a tuning fork showed diminished vibration sensation of the foot in 15 workers exposed to 1-BP but in none of the controls. 1-BP factory workers showed significantly longer distal latency in the tibial nerve than did the controls but no significant changes in motor nerve conduction velocity. Workers also displayed lower values in sensory nerve conduction velocity in the sural nerve, backward recalled digits, Benton visual memory test scores, pursuit aiming test scores, and five items of the Profile of Mood States (POMS) test (tension, depression, anxiety, fatigue, and confusion) compared with controls matched for age and education. Workers hired after May 1999, who were exposed to 1-BP only (workers hired before 1999 could have also been exposed to 2-BP), showed similar changes in vibration sense, distal latency, Benton test scores, and depression and fatigue in the POMS test. Time-weighted average exposure levels in the workers were 0.34–49.19 ppm. Exposure to 1-BP could adversely affect peripheral nerves or/and the central nervous system
Nanoscale probing of asymmetric magnetization reversal in perpendicularly exchange biased Pt/Co/Pt/IrMn multilayers
Asymmetric magnetization reversal in perpendicularly exchange biased Pt/Co/Pt/IrMn multilayers was studied in nanometer scale by non-contact magnetic force microscopy with variable highly localized bipolar magnetic fields of the MFM tip. The hysteresis process of domain nucleation and pinned domain wall motion has been triggered and mapped simultaneously through MFM. Unstable magnetization reversal of submicron domains has been directly observed as well as exchange bias induced asymmetry in the depinning fields for domain wall motion. The current results demonstrated a possible way to locally mapping and manipulating novel magnetic nano-structures such as vortices and Skyrmions
Landau Theory of the Phase Transitions in Half Doped Manganites: Interplay of Magnetic, Charge and Structural Orders
The order parameters of the magnetic, charge and structural orders at
half-doped manganites are identified. A corresponding Landau theory of the
phase transitions is formulated. Many structural and thermodynamical behaviors
are accounted for and clarified within the framework. In particular, the theory
provides a unified picture for the scenario of the phase transitions and their
nature with respect to the variation of the tolerance factor of the manganites.
It also accounts for the origin of the incommensurate nature of the orbital
order and its subsequently accompanying antiferromagnetic order.Comment: 4 pages, 3 eps figures, Revtex, Phys. Rev. B61, 200
Optimization of lipase production by Staphylococcus sp. Lp12
A bacterial strain isolated from an oil contaminated soil, identified as Staphylococcus sp. Lp12 was screened for lipase activity on tributyrin agar and spirit blue agar medium. Maximum lipase production was observed at 48 h of growth (3.5 Eu/ml). Peptone was found to be as an ideal nitrogen source for production at a concentration of 1.0% (4.25 Eu/ml). Addition of any nitrogen source other than peptone to the medium resulted in a significant reduction of enzyme production. Lower lipase production was noted when an inorganic nitrogen source was used as the sole nitrogen source. Starch was used as a major carbon source for optimum production of lipase (4.25 Eu/ml) at a concentration of 1.5%. Of the natural oils, olive oil was able to induce more lipase (4.25 Eu/ml) rather than the oils like groundnut, coconut, castor oils. Basal medium containing tween 80 enhanced lipase production to a significant level. The pH 8 and temperature 45°C were found to be ideal pH and temperature for optimum production of lipase by this strain
Excesses in the Cosmic Ray Spectrum and Possible Interpretations
The data collected by ATIC, PPB-BETS, FERMI-LAT and HESS all indicate that
there is an electron/positron excess in the cosmic ray energy spectrum above
100 GeV, although different instrumental teams do not agree on the
detailed spectral shape. PAMELA also reported a clear excess feature of the
positron fraction above several GeV, but no excess in anti-protons. Here we
review the observational status and theoretical models of this interesting
observational feature. We pay special attention to various physical
interpretations proposed in the literature, including modified supernova
remnant models for the background, new astrophysical sources, and new
physics (the dark matter models). We suggest that although most models can make
a case to interpret the data, with the current observational constraints the
dark matter interpretations, especially those invoking annihilation, require
much more exotic assumptions than some astrophysical interpretations. Future
observations may present some ``smoking-gun'' observational tests to
differentiate among different models and to identify the correct interpretation
to the phenomenon.Comment: 48 pages, including 10 figures and 1 tabel. Invited review to be
published in IJMP
- …