许多数据挖掘任务依靠图来模拟个人(节点)之间的关系结构。由于关系数据通常很敏感,因此迫切需要评估图形数据中的隐私风险。对数据分析模型的著名隐私攻击是模型反转攻击,该攻击旨在推断培训数据集中的敏感数据并引起极大的隐私问题。尽管它在类似网格的域中取得了成功,但直接应用模型反转攻击(例如图形)导致攻击性能差。这主要是由于未能考虑图的唯一属性。为了弥合这一差距,我们对模型反转攻击对图神经网络(GNNS)进行了系统研究,这是本文中最新的图形分析工具之一。首先,在攻击者可以完全访问目标GNN模型的白色框设置中,我们提出GraphMi来推断私人训练图数据。具体而言,在GraphMi中,提出了一个投影梯度模块来应对图边的离散性并保持图形特征的稀疏性和平滑度。图形自动编码器模块用于有效利用边缘推理的图形拓扑,节点属性和目标模型参数。随机采样模块最终可以采样离散边缘。此外,在攻击者只能查询GNN API并接收分类结果的硬标签黑框设置中,我们根据梯度估计和增强学习(RL-GraphMI)提出了两种方法。我们的实验结果表明,此类防御措施没有足够的有效性,并要求对隐私攻击进行更先进的防御能力。
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联合学习(FL)容易受到模型中毒攻击的影响,在该攻击中,恶意客户通过将操纵模型更新发送到服务器来破坏全局模型。现有的防御措施主要依靠拜占庭式抗体方法,即使某些客户是恶意的,旨在学习准确的全球模型。但是,在实践中,他们只能抵抗少数恶意客户。如何与大量恶意客户抗衡模型中毒攻击仍然是一个公开挑战。我们的fldetector通过检测恶意客户来应对这一挑战。 FLDETECTOR旨在检测和删除大多数恶意客户,以便拜占庭式的fl方法可以使用其余客户学习准确的全球模型。我们的主要观察结果是,在模型中毒攻击中,在多次迭代中的客户更新的模型更新是不一致的。因此,FLDetector通过检查其模型更高的一致性来检测恶意客户端。大致来说,服务器根据其历史模型更新使用Cauchy Mean Valie Therorem和L-BFG预测客户端的模型更新在多个迭代中不一致。我们在三个基准数据集上进行的广泛实验表明,FLDETECTOR可以准确检测到多种最新模型中毒攻击中的恶意客户。在删除了被检测到的恶意客户端后,现有的拜占庭式FL方法可以学习准确的全球模型。
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尽管近期图形神经网络(GNN)进展,但解释了GNN的预测仍然具有挑战性。现有的解释方法主要专注于后性后解释,其中采用另一种解释模型提供培训的GNN的解释。后HOC方法未能揭示GNN的原始推理过程的事实引发了建立GNN与内置解释性的需求。在这项工作中,我们提出了原型图形神经网络(Protgnn),其将原型学习与GNNS相结合,并提供了对GNN的解释的新视角。在Protgnn中,解释自然地从基于案例的推理过程衍生,并且实际在分类期间使用。通过将输入与潜伏空间中的一些学习原型的输入进行比较来获得ProtGnn的预测。此外,为了更好地解释性和更高的效率,结合了一种新颖的条件子图采样模块,以指示输入图的哪个部分与ProtGnn +中的每个原型最相似。最后,我们在各种数据集中评估我们的方法并进行具体的案例研究。广泛的结果表明,Protgnn和Protgnn +可以提供固有的解释性,同时实现与非可解释对方的准确性有关的准确性。
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在这项工作中,我们向图形神经网络(GNN)提出了第一个后门攻击。具体而言,我们向GNN提出一个\ emph {子画面的后门攻击},用于图表分类。在我们的后门攻击中,一旦预定义的子图注入测试图,GNN分类器就预测测试图的攻击者所选择的目标标签。我们在三个真实世界图数据集上的经验结果表明,我们的后门攻击对GNN的预测准确性的影响很小,对清洁测试图进行了很小影响。此外,我们概括了基于随机的平滑的认证防御来防御我们的后门攻击。我们的经验结果表明,在某些情况下,防御是有效的,但在其他情况下无效,突出了我们的后门攻击的新防御的需求。
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与标准动态范围(SDR)视频相比,高动态范围(HDR)视频可以代表更大的亮度和色彩范围,并且正迅速成为行业标准。与传统SDR视频相比,HDR视频具有更具挑战性的捕获,传输和显示要求。凭借其更大的深度,高级的电流传输功能以及更广泛的颜色范围,因此需要专门设计用于预测HDR视频质量的视频质量算法。为此,我们介绍了HDR视频的首次公开发布的大规模主观研究。我们研究扭曲的影响,例如压缩和混叠对HDR视频质量的影响。我们还通过在黑暗实验室环境和更明亮的客厅环境中进行研究来研究环境照明对HDR视频感知质量的影响。总共有66名受试者参加了这项研究,并收集了20,000多个意见分数,这使得这成为有史以来最大的HDR视频质量研究。我们预计,该数据集将成为研究人员为HDR视频开发更好的感知质量模型的宝贵资源。
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Masked image modeling (MIM) performs strongly in pre-training large vision Transformers (ViTs). However, small models that are critical for real-world applications cannot or only marginally benefit from this pre-training approach. In this paper, we explore distillation techniques to transfer the success of large MIM-based pre-trained models to smaller ones. We systematically study different options in the distillation framework, including distilling targets, losses, input, network regularization, sequential distillation, etc, revealing that: 1) Distilling token relations is more effective than CLS token- and feature-based distillation; 2) An intermediate layer of the teacher network as target perform better than that using the last layer when the depth of the student mismatches that of the teacher; 3) Weak regularization is preferred; etc. With these findings, we achieve significant fine-tuning accuracy improvements over the scratch MIM pre-training on ImageNet-1K classification, using all the ViT-Tiny, ViT-Small, and ViT-base models, with +4.2%/+2.4%/+1.4% gains, respectively. Our TinyMIM model of base size achieves 52.2 mIoU in AE20K semantic segmentation, which is +4.1 higher than the MAE baseline. Our TinyMIM model of tiny size achieves 79.6% top-1 accuracy on ImageNet-1K image classification, which sets a new record for small vision models of the same size and computation budget. This strong performance suggests an alternative way for developing small vision Transformer models, that is, by exploring better training methods rather than introducing inductive biases into architectures as in most previous works. Code is available at https://github.com/OliverRensu/TinyMIM.
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In this paper, we propose a robust 3D detector, named Cross Modal Transformer (CMT), for end-to-end 3D multi-modal detection. Without explicit view transformation, CMT takes the image and point clouds tokens as inputs and directly outputs accurate 3D bounding boxes. The spatial alignment of multi-modal tokens is performed implicitly, by encoding the 3D points into multi-modal features. The core design of CMT is quite simple while its performance is impressive. CMT obtains 73.0% NDS on nuScenes benchmark. Moreover, CMT has a strong robustness even if the LiDAR is missing. Code will be released at https://github.com/junjie18/CMT.
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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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Automatic music generation with artificial intelligence typically requires a large amount of data which is hard to obtain for many less common genres and musical instruments. To tackle this issue, we present ongoing work and preliminary findings on the possibility for deep models to transfer knowledge from language to music, by finetuning large language models pre-trained on a massive text corpus on only hundreds of MIDI files of drum performances. We show that by doing so, one of the largest, state-of-the-art models (GPT3) is capable of generating reasonable drum grooves, while models that are not pre-trained (Transformer) shows no such ability beyond naive repetition. Evaluating generated music is a challenging task, more so is evaluating drum grooves with little precedence in literature. Hence, we propose a tailored structural evaluation method and analyze drum grooves produced by GPT3 compared to those played by human professionals, exposing the strengths and weaknesses of such generation by language-to-music transfer. Our findings suggest that language-to-music transfer learning with large language models is viable and promising.
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