378 research outputs found
Joint-Modal Label Denoising for Weakly-Supervised Audio-Visual Video Parsing
This paper focuses on the weakly-supervised audio-visual video parsing task,
which aims to recognize all events belonging to each modality and localize
their temporal boundaries. This task is challenging because only overall labels
indicating the video events are provided for training. However, an event might
be labeled but not appear in one of the modalities, which results in a
modality-specific noisy label problem. In this work, we propose a training
strategy to identify and remove modality-specific noisy labels dynamically. It
is motivated by two key observations: 1) networks tend to learn clean samples
first; and 2) a labeled event would appear in at least one modality.
Specifically, we sort the losses of all instances within a mini-batch
individually in each modality, and then select noisy samples according to the
relationships between intra-modal and inter-modal losses. Besides, we also
propose a simple but valid noise ratio estimation method by calculating the
proportion of instances whose confidence is below a preset threshold. Our
method makes large improvements over the previous state of the arts (e.g. from
60.0\% to 63.8\% in segment-level visual metric), which demonstrates the
effectiveness of our approach. Code and trained models are publicly available
at \url{https://github.com/MCG-NJU/JoMoLD}.Comment: Accepted by ECCV 202
One-Fe versus Two-Fe Brillouin Zone of Fe-Based Superconductors: Creation of the Electron Pockets via Translational Symmetry Breaking
We investigate the physical effects of translational symmetry breaking in
Fe-based high-temperature superconductors due to alternating anion positions.
In the representative parent compounds, including the newly discovered
Fe-vacancy-ordered , an unusual change of orbital
character is found across the one-Fe Brillouin zone upon unfolding the
first-principles band structure and Fermi surfaces, suggesting that covering a
larger one-Fe Brillouin zone is necessary in experiments. Most significantly,
the electron pockets (critical to the magnetism and superconductivity) are
found only created with the broken symmetry, advocating strongly its full
inclusion in future studies, particularly on the debated nodal structures of
the superconducting order parameter.Comment: Accepted by Physical Review Letters. Updated in Figure 2 and
supplementary informatio
Existence of positive solutions for singular p-Laplacian Hadamard fractional differential equations with the derivative term contained in the nonlinear term
In this paper, based on the properties of Green function and the eigenvalue of a corresponding linear operator, the existence of positive solutions is investigated by spectral analysis for a infinite-points singular p-Laplacian Hadamard fractional differential equation boundary value problem, and an example is given to demonstrate the validity of our main results
Network modelling reveals the mechanism underlying colitis-associated colon cancer and identifies novel combinatorial anti-cancer targets
The connection between inflammation and tumourigenesis has been well established. However, the detailed molecular mechanism underlying inflammation-associated tumourigenesis remains unknown because this process involves a complex interplay between immune microenvironments and epithelial cells. To obtain a more systematic understanding of inflammation-associated tumourigenesis as well as to identify novel therapeutic approaches, we constructed a knowledge-based network describing the development of colitis-associated colon cancer (CAC) by integrating the extracellular microenvironment and intracellular signalling pathways. Dynamic simulations of the CAC network revealed a core network module, including P53, MDM2, and AKT, that may govern the malignant transformation of colon epithelial cells in a pro-tumor inflammatory microenvironment. Furthermore, in silico mutation studies and experimental validations led to a novel finding that concurrently targeting ceramide and PI3K/AKT pathway by chemical probes or marketed drugs achieves synergistic anti-cancer effects. Overall, our network model can guide further mechanistic studies on CAC and provide new insights into the design of combinatorial cancer therapies in a rational manner
On-chip three-dimensional high-Q microcavities fabricated by femtosecond laser direct writing
We report on the fabrication of three-dimensional (3D) high-Q whispering
gallery microcavities on a fused silica chip by femtosecond laser
microfabriction, enabled by the 3D nature of femtosecond laser direct writing.
The processing mainly consists of formation of freestanding microdisks by
femtosecond laser direct writing and subsequent wet chemical etching. CO2 laser
annealing is followed to smooth the microcavity surface. Microcavities with
arbitrary tilting angle, lateral and vertical positioning are demonstrated, and
the quality (Q)-factor of a typical microcavity is measured to be up to
1.07x10^6, which is currently limited by the low spatial resolution of motion
stage used during the laser patterning and can be improved with motion stages
of higher resolutions.Comment: 17 pages, 3 figure
- …