720 research outputs found
Intense ultraviolet emission from needle-like WO3 nanostructures synthesized by noncatalytic thermal evaporation
Photoluminescence measurements showed that needle-like tungsten oxide nanostructures synthesized at 590°C to 750°C by the thermal evaporation of WO3 nanopowders without the use of a catalyst had an intense near-ultraviolet (NUV) emission band that was different from that of the tungsten oxide nanostructures obtained in other temperature ranges. The intense NUV emission might be due to the localized states associated with oxygen vacancies and surface states
Programmable spectral shaping to improve the measurement precision of frequency comb mode-resolved spectral interferometric ranging
Comb-mode resolved spectral domain interferometry (CORE-SDI), which is
capable of measuring length of kilometers or more with precision on the order
of nanometers, is considered to be a promising technology for next-generation
length standards, replacing laser displacement interferometers. In this study,
we aim to improve the measurement precision of CORE-SDI using programmable
spectral shaping. We report the generation of effectively broad and symmetric
light sources through the programmable spectral shaping. The light source used
here was generated by the spectrally-broadened electro-optic comb with a
repetition rate of 17.5 GHz. Through the programmable spectral shaping, the
optical spectrum was flattened within 1 dB, resulting in a square-shaped
optical spectrum. As a result, the 3-dB spectral width was extended from 1.15
THz to 6.7 THz. We performed a comparison between the measurement results of
various spectrum shapes. We confirmed an improvement in the measurement
precision from 69 nm to 6 nm, which was also corroborated by numerical
simulations. We believe that this study on enhancing the measurement precision
of CORE-SDI through the proposed spectral shaping will make a significant
contribution to reducing the measurement uncertainty of future CORE-SDI
systems, thereby advancing the development of next-generation length standards.Comment: 22 pages, 10 figure
Public-Good Nature of Environmental Conflicts : Individual and Collective Litigations
In environmental conflicts where private citizens sue a
polluter, a private citizens participation in the fight for
environmental damages is characterized by the public good
nature. We examine how the introduction of collective litigation
and asymmetric reimbursement rule affects each citizen's choice
between free-riding and participation in the collective litigation.
Following a Stackelberg model, we assume that citizens move
first and the firm follows, while each citizen has to state his
environmental damages to the court in the process. Important
findings are as follows: First, in the individual litigation, the
hungriest citizen who most highly values environmental damages
is the only one to participate. Second, in the collective litigation,
all citizens participate, provided the total damages of the
citizens' group are sufficiently larger than the damages of the
hungriest citizen. Third, under certain conditions, introduction of
the asymmetric reimbursement rule enhances the possibility that
all citizens participate in the collective litigation
Emerging respiratory infections threatening public health in the Asia-Pacific region: a position paper of the Asian Pacific Society of Respirology
In past decades, we have seen several epidemics of
respiratory infections from newly emerging viruses,
most of which originated in animals. These emerging
infections, including severe acute respiratory syndrome
coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV) and the pandemic
influenza A(H1N1) and avian influenza (AI) viruses,
have seriously threatened global health and the economy. In particular, MERS-CoV and AI A(H7N9) are still
causing infections in several areas, and some clustering
of cases of A(H5N1) and A(H7N9) may imply future possible pandemics. Additionally, given the inappropriate
use of antibiotics and international travel, the spread of
carbapenem-resistant Gram-negative bacteria is also a
significant concern. These infections with epidemic or
pandemic potential present a persistent threat to public
health and a huge burden on healthcare services in the
Asia-Pacific region. Therefore, to enable efficient infection prevention and control, more effective international surveillance and collaboration systems, in the
context of the ‘One Health’ approach, are necessary
Multi-task Learning for Real-time Autonomous Driving Leveraging Task-adaptive Attention Generator
Real-time processing is crucial in autonomous driving systems due to the
imperative of instantaneous decision-making and rapid response. In real-world
scenarios, autonomous vehicles are continuously tasked with interpreting their
surroundings, analyzing intricate sensor data, and making decisions within
split seconds to ensure safety through numerous computer vision tasks. In this
paper, we present a new real-time multi-task network adept at three vital
autonomous driving tasks: monocular 3D object detection, semantic segmentation,
and dense depth estimation. To counter the challenge of negative transfer,
which is the prevalent issue in multi-task learning, we introduce a
task-adaptive attention generator. This generator is designed to automatically
discern interrelations across the three tasks and arrange the task-sharing
pattern, all while leveraging the efficiency of the hard-parameter sharing
approach. To the best of our knowledge, the proposed model is pioneering in its
capability to concurrently handle multiple tasks, notably 3D object detection,
while maintaining real-time processing speeds. Our rigorously optimized
network, when tested on the Cityscapes-3D datasets, consistently outperforms
various baseline models. Moreover, an in-depth ablation study substantiates the
efficacy of the methodologies integrated into our framework.Comment: Accepted at ICRA 202
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