1,879 research outputs found
Towards Adversarially Robust Continual Learning
Recent studies show that models trained by continual learning can achieve the
comparable performances as the standard supervised learning and the learning
flexibility of continual learning models enables their wide applications in the
real world. Deep learning models, however, are shown to be vulnerable to
adversarial attacks. Though there are many studies on the model robustness in
the context of standard supervised learning, protecting continual learning from
adversarial attacks has not yet been investigated. To fill in this research
gap, we are the first to study adversarial robustness in continual learning and
propose a novel method called \textbf{T}ask-\textbf{A}ware \textbf{B}oundary
\textbf{A}ugmentation (TABA) to boost the robustness of continual learning
models. With extensive experiments on CIFAR-10 and CIFAR-100, we show the
efficacy of adversarial training and TABA in defending adversarial attacks.Comment: ICASSP 202
Theoretical study of the open-flavor tetraquark in the process
Recently, the LHCb Collaboration has measured the processes
and , where the
and invariant mass distributions show the significant
signals of two new open-flavor tetraquark states and
, as the two of the isospin triplet. In this work, we
have investigated the process by taking into
account the intermediate nucleon resonance and the tetraquark state
, which could be dynamically generated by the
interactions of the and the pseoduscalar mesons-octet
baryons, respectively. Our results show that a clear peak of the open-flavor
tetraquark may appear in the invariant mass
distribution of the process , which could be tested
by future experiments.Comment: 9 pages, 11 figures, 1 tabl
The Glauber model and flow analysis with Pb-Pb collisions at =2.76 TeV
This work presents data analysis on Pb-Pb collisions at =2.76 TeV with centrality . We present introduction and
Monte-Carlo simulation results of the Glauber model, which shed light on the
initial geometric configuration of heavy ion collisions. Three-dimensional
correlation function is plotted, and Fourier decomposition is carried out in
order to obtain elliptic flow. Based on the assumption that non-flow effect is
less prominent in long-range area, we separate it from the second Fourier
decomposition of two-particle correlation function by making polynomial curve
fitting.Comment: 10 pages,8 figures, revisions are made, accepted by ICAPM 2022
Conference Proceeding
Global divergent trends of algal blooms detected by satellite during 1982–2018
Algal blooms (ABs) in inland lakes have caused adverse ecological effects, and health impairment of animals and humans. We used archived Landsat images to examine ABs in lakes (>1 km2) around the globe over a 37-year time span (1982–2018). Out of the 176032 lakes with area >1 km2 detected globally, 863 were impacted by ABs, 708 had sufficiently long records to define a trend, and 66% exhibited increasing trends in frequency ratio (FRQR, ratio of the number of ABs events observed in a year in a given lake to the number of available Landsat images for that lake) or area ratio (AR, ratio of annual maximum area covered by ABs observed in a lake to the surface area of that lake), while 34% showed a decreasing trend. Across North America, an intensification of ABs severity was observed for FRQR (p<.01) and AR (p <.01) before 1999, followed by a decrease in ABs FRQR (p <.01) and AR (p <.05) after the 2000s. The strongest intensification of ABs was observed in Asia, followed by South America, Africa, and Europe. No clear trend was detected for the Oceania. Across climatic zones, the contributions of anthropogenic factors to ABs intensification (16.5% for fertilizer, 19.4% for gross domestic product, and 18.7% for population) were slightly stronger than climatic drivers (10.1% for temperature, 11.7% for wind speed, 16.8% for pressure, and for 11.6% for rainfall). Collectively, these divergent trends indicate that consideration of anthropogenic factors as well as climate change should be at the forefront of management policies aimed at reducing the severity and frequency of ABs in inland waters
Polarity in ZnO nanowires: A critical issue for piezotronic and piezoelectric devices
The polar and piezoelectric nature of the wurtzite structure of ZnO nanowires with a high aspect ratio at nanoscale dimensions is of high interest for piezotronic and piezoelectric devices, but a number of issues related to polarity are still open and deserve a particular attention. In this context, chemical bath deposition offers a unique opportunity to select the O- or Zn-polarity of the resultant nanowires and is further compatible with the fabrication processes of flexible devices. The control and use of the polarity in ZnO nanowires grown by chemical bath deposition opens a new way to greatly enhance the performance of the related piezotronic and piezoelectric devices. However, polarity as an additional tunable parameter should be considered with care because it has a strong influence on many processes and properties. The present review is intended to report the most important consequences related to the polarity in ZnO nanowires for piezotronic and piezoelectric devices. After introducing the basic principles involving crystal polarity in ZnO, a special emphasis is placed on the effects of polarity on the nucleation and growth mechanisms of ZnO nanowires using chemical bath deposition, defect incorporation and doping, electrical contacts and device properties
Study of in decay
Using a sample of decays collected with
the BESIII detector, partial wave analyses of the decay are performed within the invariant mass region below 1.6 . The
covariant tensor amplitude method is used in both mass independent and mass
dependent approaches. Both analysis approaches exhibit dominant pseudoscalar
and axial vector components, and show good consistency for the other individual
components. Furthermore, the mass dependent analysis reveals that the
invariant mass spectrum for the pseudoscalar
component can be well described with two isoscalar resonant states, , the with a mass of
and a width of ,
and the with a mass of
and a width of .
The first and second uncertainties are statistical and systematic,
respectively. Alternate models for the pseudoscalar component are also tested,
but the description of the invariant mass spectrum
deteriorates significantly.Comment: 20 pages, 6 figures, 6 table
Amplitude analysis and branching fraction measurement of the decay \boldmath
The singly Cabibbo-suppressed decay
is observed, using a data set corresponding to an integrated luminosity of 6.32
recorded by the BESIII detector at the centre-of-mass energies
between 4.178 and 4.226 GeV. The first amplitude analysis of reveals the sub-structures in this decay and
determines the fractions and relative phases of different intermediate
processes. The dominant intermediate process is , with
a fit fraction of . With the
detection efficiency based on our amplitude analysis, the absolute branching
fraction for is measured to be
Observation of the and evidence for a new vector charmonium-like state in
Cross sections for the process
at center-of-mass energies from to GeV are measured using data
samples with a total integrated luminosity of 21.2 fb collected by the
BESIII detector operating at the BEPCII storage ring. The state is
observed in the energy dependence of the cross section for the first time with a statistical significance of
26.0. In addition, an enhancement around GeV, called the
, is seen with a statistical significance of 4.2. There is no
clear structure around GeV. Using a fit with a coherent sum of three
Breit-Wigner functions, we determine the mass and width of the state
to be MeV/ and MeV,
respectively, and the mass and width of the state to be MeV/ and MeV, respectively,
where the first uncertainties are statistical and the second are systematic. In
addition, the average Born cross section ratio of to is measured to be
, or if
three-body phase space is considered.Comment: Update draft based the comments from PRD refere
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