视频变压器在主要视频识别基准上取得了令人印象深刻的结果,但它们遭受了高计算成本。在本文中,我们呈现Stts,一个令牌选择框架,动态地在输入视频样本上调节的时间和空间尺寸的几个信息令牌。具体而言,我们将令牌选择作为一个排名问题,估计每个令牌通过轻量级选择网络的重要性,并且只有顶级分数的人将用于下游评估。在时间维度中,我们将最相关的帧保持对识别作用类别的帧,而在空间维度中,我们确定特征映射中最辨别的区域,而不会影响大多数视频变换器中以分层方式使用的空间上下文。由于令牌选择的决定是不可差异的,因此我们采用了一个扰动最大的可分辨率Top-K运算符,用于最终培训。我们对动力学-400进行广泛的实验,最近推出的视频变压器骨架MVIT。我们的框架实现了类似的结果,同时需要计算20%。我们还表明我们的方法与其他变压器架构兼容。
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我们研究了视觉变压器的培训,用于半监督图像分类。变形金刚最近在众多监督的学习任务中表现出令人印象深刻的表现。令人惊讶的是,我们发现视觉变形金刚在半监督的想象中心设置上表现不佳。相比之下,卷积神经网络(CNNS)实现了小标记数据制度的卓越结果。进一步调查揭示了原因是CNN具有强大的空间归纳偏差。灵感来自这一观察,我们介绍了一个联合半监督学习框架,半统一,其中包含变压器分支,卷积分支和精心设计的融合模块,用于分支之间的知识共享。卷积分支在有限监督数据上培训,并生成伪标签,以监督变压器分支对未标记数据的培训。关于Imagenet的广泛实验表明,半统一达到75.5 \%的前1个精度,优于最先进的。此外,我们显示Semifirmer是一般框架,与大多数现代变压器和卷积神经结构兼容。
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自我关注学习成对相互作用以模型远程依赖性,从而产生了对视频动作识别的巨大改进。在本文中,我们寻求更深入地了解视频中的时间建模的自我关注。我们首先表明通过扁平所有像素通过扁平化的时空信息的缠结建模是次优的,未明确捕获帧之间的时间关系。为此,我们介绍了全球暂时关注(GTA),以脱钩的方式在空间关注之上进行全球时间关注。我们在像素和语义类似地区上应用GTA,以捕获不同水平的空间粒度的时间关系。与计算特定于实例的注意矩阵的传统自我关注不同,GTA直接学习全局注意矩阵,该矩阵旨在编码遍布不同样本的时间结构。我们进一步增强了GTA的跨通道多头方式,以利用通道交互以获得更好的时间建模。对2D和3D网络的广泛实验表明,我们的方法一致地增强了时间建模,并在三个视频动作识别数据集中提供最先进的性能。
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Open software supply chain attacks, once successful, can exact heavy costs in mission-critical applications. As open-source ecosystems for deep learning flourish and become increasingly universal, they present attackers previously unexplored avenues to code-inject malicious backdoors in deep neural network models. This paper proposes Flareon, a small, stealthy, seemingly harmless code modification that specifically targets the data augmentation pipeline with motion-based triggers. Flareon neither alters ground-truth labels, nor modifies the training loss objective, nor does it assume prior knowledge of the victim model architecture, training data, and training hyperparameters. Yet, it has a surprisingly large ramification on training -- models trained under Flareon learn powerful target-conditional (or "any2any") backdoors. The resulting models can exhibit high attack success rates for any target choices and better clean accuracies than backdoor attacks that not only seize greater control, but also assume more restrictive attack capabilities. We also demonstrate the effectiveness of Flareon against recent defenses. Flareon is fully open-source and available online to the deep learning community: https://github.com/lafeat/flareon.
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Monitoring changes inside a reservoir in real time is crucial for the success of CO2 injection and long-term storage. Machine learning (ML) is well-suited for real-time CO2 monitoring because of its computational efficiency. However, most existing applications of ML yield only one prediction (i.e., the expectation) for a given input, which may not properly reflect the distribution of the testing data, if it has a shift with respect to that of the training data. The Simultaneous Quantile Regression (SQR) method can estimate the entire conditional distribution of the target variable of a neural network via pinball loss. Here, we incorporate this technique into seismic inversion for purposes of CO2 monitoring. The uncertainty map is then calculated pixel by pixel from a particular prediction interval around the median. We also propose a novel data-augmentation method by sampling the uncertainty to further improve prediction accuracy. The developed methodology is tested on synthetic Kimberlina data, which are created by the Department of Energy and based on a CO2 capture and sequestration (CCS) project in California. The results prove that the proposed network can estimate the subsurface velocity rapidly and with sufficient resolution. Furthermore, the computed uncertainty quantifies the prediction accuracy. The method remains robust even if the testing data are distorted due to problems in the field data acquisition. Another test demonstrates the effectiveness of the developed data-augmentation method in increasing the spatial resolution of the estimated velocity field and in reducing the prediction error.
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网络在许多现实世界应用程序中无处不在(例如,编码信任/不信任关系的社交网络,由时间序列数据引起的相关网络)。尽管许多网络都是签名或指示的,或者两者都在图形神经网络(GNN)上缺少统一的软件包,专门为签名和定向网络设计。在本文中,我们提出了Pytorch几何签名的指示,这是一个填补此空白的软件包。在此过程中,我们还提供了简短的审查调查,以分析签名和定向网络的分析,讨论相关实验中使用的数据,提供提出的方法概述,并通过实验评估实施方法。深度学习框架包括易于使用的GNN模型,合成和现实世界数据,以及针对签名和定向网络的特定任务评估指标和损失功能。作为Pytorch几何形状的扩展库,我们提出的软件由开源版本,详细文档,连续集成,单位测试和代码覆盖范围检查维护。我们的代码可在\ url {https://github.com/sherylhyx/pytorch_geometric_signed_directed}上公开获得。
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我们展示了OpenFWI,是用于地震全波形反演(FWI)的大型开源基准数据集的集合。OpenFWI是地球科学和机器学习界的一流,以促进对基于机器学习的FWI多元化,严谨和可重复的研究。OpenFWI包括多个尺度的数据集,包含不同的域,涵盖各种级别的模型复杂性。除了数据集之外,我们还对每个数据集进行实证研究,具有完全卷积的深度学习模型。OpenFWI已被核心维护,并将通过新数据和实验结果定期更新。我们感谢社区的投入,帮助我们进一步改进OpenFWI。在当前版本,我们在OpenFWI中发布了七个数据集,其中为3D FWI指定了一个,其余的是2D场景。所有数据集和相关信息都可以通过我们的网站访问https://openfwi.github.io/。
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Dataset distillation has emerged as a prominent technique to improve data efficiency when training machine learning models. It encapsulates the knowledge from a large dataset into a smaller synthetic dataset. A model trained on this smaller distilled dataset can attain comparable performance to a model trained on the original training dataset. However, the existing dataset distillation techniques mainly aim at achieving the best trade-off between resource usage efficiency and model utility. The security risks stemming from them have not been explored. This study performs the first backdoor attack against the models trained on the data distilled by dataset distillation models in the image domain. Concretely, we inject triggers into the synthetic data during the distillation procedure rather than during the model training stage, where all previous attacks are performed. We propose two types of backdoor attacks, namely NAIVEATTACK and DOORPING. NAIVEATTACK simply adds triggers to the raw data at the initial distillation phase, while DOORPING iteratively updates the triggers during the entire distillation procedure. We conduct extensive evaluations on multiple datasets, architectures, and dataset distillation techniques. Empirical evaluation shows that NAIVEATTACK achieves decent attack success rate (ASR) scores in some cases, while DOORPING reaches higher ASR scores (close to 1.0) in all cases. Furthermore, we conduct a comprehensive ablation study to analyze the factors that may affect the attack performance. Finally, we evaluate multiple defense mechanisms against our backdoor attacks and show that our attacks can practically circumvent these defense mechanisms.
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Blind image quality assessment (BIQA) remains challenging due to the diversity of distortion and image content variation, which complicate the distortion patterns crossing different scales and aggravate the difficulty of the regression problem for BIQA. However, existing BIQA methods often fail to consider multi-scale distortion patterns and image content, and little research has been done on learning strategies to make the regression model produce better performance. In this paper, we propose a simple yet effective Progressive Multi-Task Image Quality Assessment (PMT-IQA) model, which contains a multi-scale feature extraction module (MS) and a progressive multi-task learning module (PMT), to help the model learn complex distortion patterns and better optimize the regression issue to align with the law of human learning process from easy to hard. To verify the effectiveness of the proposed PMT-IQA model, we conduct experiments on four widely used public datasets, and the experimental results indicate that the performance of PMT-IQA is superior to the comparison approaches, and both MS and PMT modules improve the model's performance.
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The development of social media user stance detection and bot detection methods rely heavily on large-scale and high-quality benchmarks. However, in addition to low annotation quality, existing benchmarks generally have incomplete user relationships, suppressing graph-based account detection research. To address these issues, we propose a Multi-Relational Graph-Based Twitter Account Detection Benchmark (MGTAB), the first standardized graph-based benchmark for account detection. To our knowledge, MGTAB was built based on the largest original data in the field, with over 1.55 million users and 130 million tweets. MGTAB contains 10,199 expert-annotated users and 7 types of relationships, ensuring high-quality annotation and diversified relations. In MGTAB, we extracted the 20 user property features with the greatest information gain and user tweet features as the user features. In addition, we performed a thorough evaluation of MGTAB and other public datasets. Our experiments found that graph-based approaches are generally more effective than feature-based approaches and perform better when introducing multiple relations. By analyzing experiment results, we identify effective approaches for account detection and provide potential future research directions in this field. Our benchmark and standardized evaluation procedures are freely available at: https://github.com/GraphDetec/MGTAB.
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