13 research outputs found
SmooSeg: Smoothness Prior for Unsupervised Semantic Segmentation
Unsupervised semantic segmentation is a challenging task that segments images
into semantic groups without manual annotation. Prior works have primarily
focused on leveraging prior knowledge of semantic consistency or priori
concepts from self-supervised learning methods, which often overlook the
coherence property of image segments. In this paper, we demonstrate that the
smoothness prior, asserting that close features in a metric space share the
same semantics, can significantly simplify segmentation by casting unsupervised
semantic segmentation as an energy minimization problem. Under this paradigm,
we propose a novel approach called SmooSeg that harnesses self-supervised
learning methods to model the closeness relationships among observations as
smoothness signals. To effectively discover coherent semantic segments, we
introduce a novel smoothness loss that promotes piecewise smoothness within
segments while preserving discontinuities across different segments.
Additionally, to further enhance segmentation quality, we design an asymmetric
teacher-student style predictor that generates smoothly updated pseudo labels,
facilitating an optimal fit between observations and labeling outputs. Thanks
to the rich supervision cues of the smoothness prior, our SmooSeg significantly
outperforms STEGO in terms of pixel accuracy on three datasets: COCOStuff
(+14.9%), Cityscapes (+13.0%), and Potsdam-3 (+5.7%).Comment: Accepted by NeurIPS 2023. Code available:
https://github.com/mc-lan/SmooSe
MIMO Is All You Need : A Strong Multi-In-Multi-Out Baseline for Video Prediction
The mainstream of the existing approaches for video prediction builds up
their models based on a Single-In-Single-Out (SISO) architecture, which takes
the current frame as input to predict the next frame in a recursive manner.
This way often leads to severe performance degradation when they try to
extrapolate a longer period of future, thus limiting the practical use of the
prediction model. Alternatively, a Multi-In-Multi-Out (MIMO) architecture that
outputs all the future frames at one shot naturally breaks the recursive manner
and therefore prevents error accumulation. However, only a few MIMO models for
video prediction are proposed and they only achieve inferior performance due to
the date. The real strength of the MIMO model in this area is not well noticed
and is largely under-explored. Motivated by that, we conduct a comprehensive
investigation in this paper to thoroughly exploit how far a simple MIMO
architecture can go. Surprisingly, our empirical studies reveal that a simple
MIMO model can outperform the state-of-the-art work with a large margin much
more than expected, especially in dealing with longterm error accumulation.
After exploring a number of ways and designs, we propose a new MIMO
architecture based on extending the pure Transformer with local spatio-temporal
blocks and a new multi-output decoder, namely MIMO-VP, to establish a new
standard in video prediction. We evaluate our model in four highly competitive
benchmarks (Moving MNIST, Human3.6M, Weather, KITTI). Extensive experiments
show that our model wins 1st place on all the benchmarks with remarkable
performance gains and surpasses the best SISO model in all aspects including
efficiency, quantity, and quality. We believe our model can serve as a new
baseline to facilitate the future research of video prediction tasks. The code
will be released
Dual functions for the ssDNA-binding protein RPA in meiotic recombination.
Meiotic recombination permits exchange of genetic material between homologous chromosomes. The replication protein A (RPA) complex, the predominant ssDNA-binding complex, is required for nearly all aspects of DNA metabolism, but its role in mammalian meiotic recombination remains unknown due to the embryonic lethality of RPA mutant mice. RPA is a heterotrimer of RPA1, RPA2, and RPA3. We find that loss of RPA1, the largest subunit, leads to disappearance of RPA2 and RPA3, resulting in the absence of the RPA complex. Using an inducible germline-specific inactivation strategy, we find that loss of RPA completely abrogates loading of RAD51/DMC1 recombinases to programmed meiotic DNA double strand breaks, thus blocking strand invasion required for chromosome pairing and synapsis. Surprisingly, loading of MEIOB, SPATA22, and ATR to DNA double strand breaks is RPA-independent and does not promote RAD51/DMC1 recruitment in the absence of RPA. Finally, inactivation of RPA reduces crossover formation. Our results demonstrate that RPA plays two distinct roles in meiotic recombination: an essential role in recombinase recruitment at early stages and an important role in promoting crossover formation at later stages
CEPC Technical Design Report -- Accelerator
International audienceThe Circular Electron Positron Collider (CEPC) is a large scientific project initiated and hosted by China, fostered through extensive collaboration with international partners. The complex comprises four accelerators: a 30 GeV Linac, a 1.1 GeV Damping Ring, a Booster capable of achieving energies up to 180 GeV, and a Collider operating at varying energy modes (Z, W, H, and ttbar). The Linac and Damping Ring are situated on the surface, while the Booster and Collider are housed in a 100 km circumference underground tunnel, strategically accommodating future expansion with provisions for a Super Proton Proton Collider (SPPC). The CEPC primarily serves as a Higgs factory. In its baseline design with synchrotron radiation (SR) power of 30 MW per beam, it can achieve a luminosity of 5e34 /cm^2/s^1, resulting in an integrated luminosity of 13 /ab for two interaction points over a decade, producing 2.6 million Higgs bosons. Increasing the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons, facilitating precise measurements of Higgs coupling at sub-percent levels, exceeding the precision expected from the HL-LHC by an order of magnitude. This Technical Design Report (TDR) follows the Preliminary Conceptual Design Report (Pre-CDR, 2015) and the Conceptual Design Report (CDR, 2018), comprehensively detailing the machine's layout and performance, physical design and analysis, technical systems design, R&D and prototyping efforts, and associated civil engineering aspects. Additionally, it includes a cost estimate and a preliminary construction timeline, establishing a framework for forthcoming engineering design phase and site selection procedures. Construction is anticipated to begin around 2027-2028, pending government approval, with an estimated duration of 8 years. The commencement of experiments could potentially initiate in the mid-2030s
CEPC Technical Design Report -- Accelerator
International audienceThe Circular Electron Positron Collider (CEPC) is a large scientific project initiated and hosted by China, fostered through extensive collaboration with international partners. The complex comprises four accelerators: a 30 GeV Linac, a 1.1 GeV Damping Ring, a Booster capable of achieving energies up to 180 GeV, and a Collider operating at varying energy modes (Z, W, H, and ttbar). The Linac and Damping Ring are situated on the surface, while the Booster and Collider are housed in a 100 km circumference underground tunnel, strategically accommodating future expansion with provisions for a Super Proton Proton Collider (SPPC). The CEPC primarily serves as a Higgs factory. In its baseline design with synchrotron radiation (SR) power of 30 MW per beam, it can achieve a luminosity of 5e34 /cm^2/s^1, resulting in an integrated luminosity of 13 /ab for two interaction points over a decade, producing 2.6 million Higgs bosons. Increasing the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons, facilitating precise measurements of Higgs coupling at sub-percent levels, exceeding the precision expected from the HL-LHC by an order of magnitude. This Technical Design Report (TDR) follows the Preliminary Conceptual Design Report (Pre-CDR, 2015) and the Conceptual Design Report (CDR, 2018), comprehensively detailing the machine's layout and performance, physical design and analysis, technical systems design, R&D and prototyping efforts, and associated civil engineering aspects. Additionally, it includes a cost estimate and a preliminary construction timeline, establishing a framework for forthcoming engineering design phase and site selection procedures. Construction is anticipated to begin around 2027-2028, pending government approval, with an estimated duration of 8 years. The commencement of experiments could potentially initiate in the mid-2030s
CEPC Technical Design Report -- Accelerator
International audienceThe Circular Electron Positron Collider (CEPC) is a large scientific project initiated and hosted by China, fostered through extensive collaboration with international partners. The complex comprises four accelerators: a 30 GeV Linac, a 1.1 GeV Damping Ring, a Booster capable of achieving energies up to 180 GeV, and a Collider operating at varying energy modes (Z, W, H, and ttbar). The Linac and Damping Ring are situated on the surface, while the Booster and Collider are housed in a 100 km circumference underground tunnel, strategically accommodating future expansion with provisions for a Super Proton Proton Collider (SPPC). The CEPC primarily serves as a Higgs factory. In its baseline design with synchrotron radiation (SR) power of 30 MW per beam, it can achieve a luminosity of 5e34 /cm^2/s^1, resulting in an integrated luminosity of 13 /ab for two interaction points over a decade, producing 2.6 million Higgs bosons. Increasing the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons, facilitating precise measurements of Higgs coupling at sub-percent levels, exceeding the precision expected from the HL-LHC by an order of magnitude. This Technical Design Report (TDR) follows the Preliminary Conceptual Design Report (Pre-CDR, 2015) and the Conceptual Design Report (CDR, 2018), comprehensively detailing the machine's layout and performance, physical design and analysis, technical systems design, R&D and prototyping efforts, and associated civil engineering aspects. Additionally, it includes a cost estimate and a preliminary construction timeline, establishing a framework for forthcoming engineering design phase and site selection procedures. Construction is anticipated to begin around 2027-2028, pending government approval, with an estimated duration of 8 years. The commencement of experiments could potentially initiate in the mid-2030s