104 research outputs found
Improving Generative Model-based Unfolding with Schr\"{o}dinger Bridges
Machine learning-based unfolding has enabled unbinned and high-dimensional
differential cross section measurements. Two main approaches have emerged in
this research area: one based on discriminative models and one based on
generative models. The main advantage of discriminative models is that they
learn a small correction to a starting simulation while generative models scale
better to regions of phase space with little data. We propose to use
Schroedinger Bridges and diffusion models to create SBUnfold, an unfolding
approach that combines the strengths of both discriminative and generative
models. The key feature of SBUnfold is that its generative model maps one set
of events into another without having to go through a known probability density
as is the case for normalizing flows and standard diffusion models. We show
that SBUnfold achieves excellent performance compared to state of the art
methods on a synthetic Z+jets dataset.Comment: 9 pages, 5 figure
Identity-Guided Collaborative Learning for Cloth-Changing Person Reidentification
Cloth-changing person reidentification (ReID) is a newly emerging research
topic that is aimed at addressing the issues of large feature variations due to
cloth-changing and pedestrian view/pose changes. Although significant progress
has been achieved by introducing extra information (e.g., human contour
sketching information, human body keypoints, and 3D human information),
cloth-changing person ReID is still challenging due to impressionable
pedestrian representations. Moreover, human semantic information and pedestrian
identity information are not fully explored. To solve these issues, we propose
a novel identity-guided collaborative learning scheme (IGCL) for cloth-changing
person ReID, where the human semantic is fully utilized and the identity is
unchangeable to guide collaborative learning. First, we design a novel clothing
attention degradation stream to reasonably reduce the interference caused by
clothing information where clothing attention and mid-level collaborative
learning are employed. Second, we propose a human semantic attention and body
jigsaw stream to highlight the human semantic information and simulate
different poses of the same identity. In this way, the extraction features not
only focus on human semantic information that is unrelated to the background
but also are suitable for pedestrian pose variations. Moreover, a pedestrian
identity enhancement stream is further proposed to enhance the identity
importance and extract more favorable identity robust features. Most
importantly, all these streams are jointly explored in an end-to-end unified
framework, and the identity is utilized to guide the optimization. Extensive
experiments on five public clothing person ReID datasets demonstrate that the
proposed IGCL significantly outperforms SOTA methods and that the extracted
feature is more robust, discriminative, and clothing-irrelevant
Knowledge-Aware Prompt Tuning for Generalizable Vision-Language Models
Pre-trained vision-language models, e.g., CLIP, working with manually
designed prompts have demonstrated great capacity of transfer learning.
Recently, learnable prompts achieve state-of-the-art performance, which however
are prone to overfit to seen classes, failing to generalize to unseen classes.
In this paper, we propose a Knowledge-Aware Prompt Tuning (KAPT) framework for
vision-language models. Our approach takes inspiration from human intelligence
in which external knowledge is usually incorporated into recognizing novel
categories of objects. Specifically, we design two complementary types of
knowledge-aware prompts for the text encoder to leverage the distinctive
characteristics of category-related external knowledge. The discrete prompt
extracts the key information from descriptions of an object category, and the
learned continuous prompt captures overall contexts. We further design an
adaptation head for the visual encoder to aggregate salient attentive visual
cues, which establishes discriminative and task-aware visual representations.
We conduct extensive experiments on 11 widely-used benchmark datasets and the
results verify the effectiveness in few-shot image classification, especially
in generalizing to unseen categories. Compared with the state-of-the-art CoCoOp
method, KAPT exhibits favorable performance and achieves an absolute gain of
3.22% on new classes and 2.57% in terms of harmonic mean.Comment: Accepted by ICCV 202
Contrast-augmented Diffusion Model with Fine-grained Sequence Alignment for Markup-to-Image Generation
The recently rising markup-to-image generation poses greater challenges as
compared to natural image generation, due to its low tolerance for errors as
well as the complex sequence and context correlations between markup and
rendered image. This paper proposes a novel model named "Contrast-augmented
Diffusion Model with Fine-grained Sequence Alignment" (FSA-CDM), which
introduces contrastive positive/negative samples into the diffusion model to
boost performance for markup-to-image generation. Technically, we design a
fine-grained cross-modal alignment module to well explore the sequence
similarity between the two modalities for learning robust feature
representations. To improve the generalization ability, we propose a
contrast-augmented diffusion model to explicitly explore positive and negative
samples by maximizing a novel contrastive variational objective, which is
mathematically inferred to provide a tighter bound for the model's
optimization. Moreover, the context-aware cross attention module is developed
to capture the contextual information within markup language during the
denoising process, yielding better noise prediction results. Extensive
experiments are conducted on four benchmark datasets from different domains,
and the experimental results demonstrate the effectiveness of the proposed
components in FSA-CDM, significantly exceeding state-of-the-art performance by
about 2%-12% DTW improvements. The code will be released at
https://github.com/zgj77/FSACDM.Comment: Accepted to ACM MM 2023. The code will be released at
https://github.com/zgj77/FSACD
Greenhouse gas emissions from municipal wastewater treatment facilities in China from 2006 to 2019
Wastewater treatment plants (WWTPs) alleviate water pollution but also induce resource consumption and environmental impacts especially greenhouse gas (GHG) emissions. Mitigating GHG emissions of WWTPs can contribute to achieving carbon neutrality in China. But there is still a lack of a high-resolution and time-series GHG emission inventories of WWTPs in China. In this study, we construct a firm-level emission inventory of WWTPs for CH4, N2O and CO2 emissions from different wastewater treatment processes, energy consumption and effluent discharge for the time-period from 2006 to 2019. We aim to develop a transparent, verifiable and comparable WWTP GHG emission inventory to support GHG mitigation of WWTPs in China
Reassortant between Human-Like H3N2 and Avian H5 Subtype Influenza A Viruses in Pigs: A Potential Public Health Risk
Human-like H3N2 influenza viruses have repeatedly been transmitted to domestic pigs in different regions of the world, but it is still uncertain whether any of these variants could become established in pig populations. The fact that different subtypes of influenza viruses have been detected in pigs makes them an ideal candidate for the genesis of a possible reassortant virus with both human and avian origins. However, the determination of whether pigs can act as a “mixing vessel” for a possible future pandemic virus is still pending an answer. This prompted us to gather the epidemiological information and investigate the genetic evolution of swine influenza viruses in Jilin, China.Nasopharyngeal swabs were collected from pigs with respiratory illness in Jilin province, China from July 2007 to October 2008. All samples were screened for influenza A viruses. Three H3N2 swine influenza virus isolates were analyzed genetically and phylogenetically.Influenza surveillance of pigs in Jilin province, China revealed that H3N2 influenza viruses were regularly detected from domestic pigs during 2007 to 2008. Phylogenetic analysis revealed that two distinguishable groups of H3N2 influenza viruses were present in pigs: the wholly contemporary human-like H3N2 viruses (represented by the Moscow/10/99-like sublineage) and double-reassortant viruses containing genes from contemporary human H3N2 viruses and avian H5 viruses, both co-circulating in pig populations.The present study reports for the first time the coexistence of wholly human-like H3N2 viruses and double-reassortant viruses that have emerged in pigs in Jilin, China. It provides updated information on the role of pigs in interspecies transmission and genetic reassortment of influenza viruses
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