Estimating the structure of directed acyclic graphs (DAGs) of features (variables) plays a vital role in revealing the latent data generation process and providing causal insights in various applications. Although there have been many studies on structure learning with various types of data, the structure learning on the dynamic graph has not been explored yet, and thus we study the learning problem of node feature generation mechanism on such ubiquitous dynamic graph data. In a dynamic graph, we propose to simultaneously estimate contemporaneous relationships and time-lagged interaction relationships between the node features. These two kinds of relationships form a DAG, which could effectively characterize the feature generation process in a concise way. To learn such a DAG, we cast the learning problem as a continuous score-based optimization problem, which consists of a differentiable score function to measure the validity of the learned DAGs and a smooth acyclicity constraint to ensure the acyclicity of the learned DAGs. These two components are translated into an unconstraint augmented Lagrangian objective which could be minimized by mature continuous optimization techniques. The resulting algorithm, named GraphNOTEARS, outperforms baselines on simulated data across a wide range of settings that may encounter in real-world applications. We also apply the proposed approach on two dynamic graphs constructed from the real-world Yelp dataset, demonstrating our method could learn the connections between node features, which conforms with the domain knowledge.
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大多数图形神经网络(GNN)通过学习输入图和标签之间的相关性来预测看不见的图的标签。但是,通过对具有严重偏见的训练图进行图形分类调查,我们发现GNN始终倾向于探索伪造的相关性以做出决定,即使因果关系始终存在。这意味着在此类偏见的数据集中接受培训的现有GNN将遭受概括能力差。通过在因果观点中分析此问题,我们发现从偏见图中解开和去偏置因果和偏见的潜在变量对于偏见至关重要。在此鼓舞下,我们提出了一个普遍的分解GNN框架,分别学习因果子结构和偏见子结构。特别是,我们设计了一个参数化的边蒙版生成器,以将输入图明确分为因果和偏置子图。然后,分别由因果/偏见感知损失函数监督的两个GNN模块进行培训,以编码因果关系和偏置子图表中的相应表示。通过分离的表示,我们合成了反事实无偏的训练样本,以进一步脱离因果变量和偏见变量。此外,为了更好地基于严重的偏见问题,我们构建了三个新的图形数据集,这些数据集具有可控的偏置度,并且更容易可视化和解释。实验结果很好地表明,我们的方法比现有基线实现了优越的概括性能。此外,由于学习的边缘面膜,该拟议的模型具有吸引人的解释性和可转让性。代码和数据可在以下网址获得:https://github.com/googlebaba/disc。
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逐渐射击的语义分割(IFSS)目标以逐步扩展模型的能力逐渐扩大了仅由几个样本监督的新图像。但是,在旧课程中学到的特征可能会大大漂移,从而导致灾难性遗忘。此外,很少有针对新课程的像素级细分样本会导致每个学习课程中臭名昭著的过度拟合问题。在本文中,我们明确表示基于类别的语义分割的知识作为类别嵌入和超级类嵌入,前者描述了独家的语义属性,而后者则表示超级类知识作为类共享语义属性。为了解决IFSS问题,我们提出了EHNET,即从两个方面嵌入自适应更高和超级级表示网络。首先,我们提出了一种嵌入自适应的策略,以避免特征漂移,该策略通过超级班级表示保持旧知识,并使用类似课程的方案自适应地更新类别嵌入类别,以涉及在各个会话中学习的新课程。其次,为了抵制很少有培训样本引起的过度拟合问题,通过将所有类别嵌入以进行初始化并与新班级的类别保持一致以进行增强,从而学习了超级班级的嵌入,从而使学会知识有助于学习新知识,从而减轻了绩效绩效的绩效,依赖培训数据量表。值得注意的是,这两种设计为具有足够语义和有限偏见的类提供了表示能力,从而可以执行需要高语义依赖性的分割任务。 Pascal-5i和可可数据集的实验表明,EHNET具有显着优势的新最先进的性能。
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由少量镜头组成的全景环形镜头(PAL)在全景周围具有巨大潜力,该镜头围绕着移动和可穿戴设备的传感任务,因为其尺寸很小,并且视野很大(FOV)。然而,由于缺乏畸变校正的镜头,小体积PAL的图像质量仅限于光学极限。在本文中,我们提出了一个环形计算成像(ACI)框架,以打破轻质PAL设计的光学限制。为了促进基于学习的图像恢复,我们引入了基于波浪的模拟管道,用于全景成像,并通过多个数据分布来应对合成间隙。提出的管道可以轻松地适应具有设计参数的任何PAL,并且适用于宽松的设计。此外,我们考虑了全景成像和物理知识学习的物理先验,我们设计了物理知情的图像恢复网络(PI2RNET)。在数据集级别,我们创建了Divpano数据集,其广泛的实验表明,我们提出的网络在空间变化的降级下在全景图像恢复中设置了新的最新技术。此外,对只有3个球形镜头的简单PAL上提议的ACI的评估揭示了高质量全景成像与紧凑设计之间的微妙平衡。据我们所知,我们是第一个探索PAL中计算成像(CI)的人。代码和数据集将在https://github.com/zju-jiangqi/aci-pi2rnet上公开提供。
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建议图表神经网络(GNNS)在不考虑训练和测试图之间的不可知分布的情况下,诱导GNN的泛化能力退化在分布外(OOD)设置。这种退化的根本原因是大多数GNN是基于I.I.D假设开发的。在这种设置中,GNN倾向于利用在培训中存在的微妙统计相关性用于预测,即使它是杂散的相关性。然而,这种杂散的相关性可能在测试环境中改变,导致GNN的失败。因此,消除了杂散相关的影响对于稳定的GNN来说是至关重要的。为此,我们提出了一个普遍的因果代表框架,称为稳定凝球。主要思想是首先从图数据中提取高级表示,并诉诸因因果推理的显着能力,以帮助模型摆脱虚假相关性。特别是,我们利用图形池化层以提取基于子图的表示作为高级表示。此外,我们提出了一种因果变量区别,以纠正偏置训练分布。因此,GNN将更多地集中在稳定的相关性上。对合成和现实世界ood图数据集的广泛实验良好地验证了所提出的框架的有效性,灵活性和可解释性。
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现代物体检测网络追求一般物体检测数据集的更高精度,同时计算负担也随着精度的提高而越来越多。然而,推理时间和精度对于需要是实时的对象检测系统至关重要。没有额外的计算成本,有必要研究精度改进。在这项工作中,提出了两种模块以提高零成本的检测精度,这是一般对象检测网络的FPN和检测头改进。我们采用规模注意机制,以有效地保险熔断多级功能映射,参数较少,称为SA-FPN模块。考虑到分类头和回归头的相关性,我们使用顺序头取代广泛使用的并联头部,称为SEQ-Head模块。为了评估有效性,我们将这两个模块应用于一些现代最先进的对象检测网络,包括基于锚和无锚。 Coco DataSet上的实验结果表明,具有两个模块的网络可以将原始网络超越1.1 AP和0.8 AP,分别为锚的锚和无锚网络的零成本。代码将在https://git.io/jtfgl提供。
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Localizing anatomical landmarks are important tasks in medical image analysis. However, the landmarks to be localized often lack prominent visual features. Their locations are elusive and easily confused with the background, and thus precise localization highly depends on the context formed by their surrounding areas. In addition, the required precision is usually higher than segmentation and object detection tasks. Therefore, localization has its unique challenges different from segmentation or detection. In this paper, we propose a zoom-in attentive network (ZIAN) for anatomical landmark localization in ocular images. First, a coarse-to-fine, or "zoom-in" strategy is utilized to learn the contextualized features in different scales. Then, an attentive fusion module is adopted to aggregate multi-scale features, which consists of 1) a co-attention network with a multiple regions-of-interest (ROIs) scheme that learns complementary features from the multiple ROIs, 2) an attention-based fusion module which integrates the multi-ROIs features and non-ROI features. We evaluated ZIAN on two open challenge tasks, i.e., the fovea localization in fundus images and scleral spur localization in AS-OCT images. Experiments show that ZIAN achieves promising performances and outperforms state-of-the-art localization methods. The source code and trained models of ZIAN are available at https://github.com/leixiaofeng-astar/OMIA9-ZIAN.
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当前,借助监督学习方法,基于深度学习的视觉检查已取得了非常成功的成功。但是,在实际的工业场景中,缺陷样本的稀缺性,注释的成本以及缺乏缺陷的先验知识可能会使基于监督的方法无效。近年来,无监督的异常定位算法已在工业检查任务中广泛使用。本文旨在通过深入学习在工业图像中无视无视的异常定位中的最新成就来帮助该领域的研究人员。该调查回顾了120多个重要出版物,其中涵盖了异常定位的各个方面,主要涵盖了所审查方法的各种概念,挑战,分类法,基准数据集和定量性能比较。在审查迄今为止的成就时,本文提供了一些未来研究方向的详细预测和分析。这篇综述为对工业异常本地化感兴趣的研究人员提供了详细的技术信息,并希望将其应用于其他领域的异常本质。
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With the rapid development of artificial intelligence (AI) in medical image processing, deep learning in color fundus photography (CFP) analysis is also evolving. Although there are some open-source, labeled datasets of CFPs in the ophthalmology community, large-scale datasets for screening only have labels of disease categories, and datasets with annotations of fundus structures are usually small in size. In addition, labeling standards are not uniform across datasets, and there is no clear information on the acquisition device. Here we release a multi-annotation, multi-quality, and multi-device color fundus image dataset for glaucoma analysis on an original challenge -- Retinal Fundus Glaucoma Challenge 2nd Edition (REFUGE2). The REFUGE2 dataset contains 2000 color fundus images with annotations of glaucoma classification, optic disc/cup segmentation, as well as fovea localization. Meanwhile, the REFUGE2 challenge sets three sub-tasks of automatic glaucoma diagnosis and fundus structure analysis and provides an online evaluation framework. Based on the characteristics of multi-device and multi-quality data, some methods with strong generalizations are provided in the challenge to make the predictions more robust. This shows that REFUGE2 brings attention to the characteristics of real-world multi-domain data, bridging the gap between scientific research and clinical application.
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自动放射学报告生成在诊所至关重要,可以缓解来自繁重的工作量的经验丰富的放射科医师,并提醒缺乏误诊或错过诊断的缺乏经验的放射科学家。现有方法主要将放射学报告生成作为图像标题任务,采用编码器解码器框架。但是,在医学领域,这种纯数据驱动方法遭受以下问题:1)视觉和文本偏差问题; 2)缺乏专家知识。在本文中,我们提出了一种知识增强的放射学报告生成方法,介绍了两种类型的医学知识:1)一般知识,这是输入的独立知识,并为报告生成提供了广泛的知识; 2)特定知识,其输入依赖并为报告生成提供了细粒度的知识。为了充分利用一般和具体知识,我们还提出了一种知识增强的多主题注意机制。通过利用一般知识和特定知识来利用放射线图像的视觉特征,所提出的模型可以提高所生成的报告的质量。两种公共数据集IU-X射线和模拟CXR的实验结果表明,所提出的知识增强方法优于基于最先进的图像标题的方法。消融研究还表明,一般和具体知识都可以有助于提高放射学报告生成的表现。
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