胸部X射线（CXR）图像中的肺结节检测是肺癌的早期筛查。基于深度学习的计算机辅助诊断（CAD）系统可以支持放射线医生在CXR中进行结节筛选。但是，它需要具有高质量注释的大规模和多样化的医学数据，以训练这种强大而准确的CAD。为了减轻此类数据集的有限可用性，为了增加数据增强而提出了肺结核合成方法。然而，以前的方法缺乏产生结节的能力，这些结节与检测器所需的大小属性相关。为了解决这个问题，我们在本文中介绍了一种新颖的肺结综合框架，该框架分别将结节属性分为三个主要方面，包括形状，大小和纹理。基于GAN的形状生成器首先通过产生各种形状掩模来建模结节形状。然后，以下大小调制可以对像素级粒度中生成的结节形状的直径进行定量控制。一条粗到细门的卷积卷积纹理发生器最终合成了以调制形状掩模为条件的视觉上合理的结节纹理。此外，我们建议通过控制数据增强的分离结节属性来合成结节CXR图像，以便更好地补偿检测任务中容易错过的结节。我们的实验证明了所提出的肺结构合成框架的图像质量，多样性和可控性的增强。我们还验证了数据增强对大大改善结节检测性能的有效性。

我们考虑临床应用异常定位问题。虽然深入学习推动了最近的医学成像进展，但许多临床挑战都没有完全解决，限制了其更广泛的使用。虽然最近的方法报告了高的诊断准确性，但医生因普遍缺乏算法决策和解释性而涉及诊断决策的这些算法，这是关注这些算法。解决这个问题的一种潜在方法是进一步培训这些模型，以便除了分类它们之外，除了分类。然而，准确地进行这一临床专家需要大量的疾病定位注释，这是对大多数应用程序来实现昂贵的任务。在这项工作中，我们通过一种新的注意力弱监督算法来解决这些问题，该弱势监督算法包括分层关注挖掘框架，可以以整体方式统一激活和基于梯度的视觉关注。我们的关键算法创新包括明确序号注意约束的设计，实现了以弱监督的方式实现了原则的模型培训，同时还通过本地化线索促进了产生视觉关注驱动的模型解释。在两个大型胸部X射线数据集（NIH Chescx-Ray14和Chexpert）上，我们展示了对现有技术的显着本地化性能，同时也实现了竞争的分类性能。我们的代码可在https://github.com/oyxhust/ham上找到。

病变检测是乳房X线照相术的计算机辅助诊断方案中的一个基本问题。如果培训数据在图像风格和质量方面，深度学习技术的进步对这项任务产生了显着的进展。特别地，图像样式的多样性可能主要归因于供应商因子。然而，尽可能多的供应商收集来自供应商的非常昂贵，并且有时对于实验室规模研究是不切实际的。因此，为了进一步将深度学习模型的泛化能力扩展到具有有限资源有限的各种供应商，开发了一种新的对比学习方案。具体地，骨干网络首先具有多种式和多视图无监督的自学习方案，用于将不变功能嵌入到各种供应商样式中。之后，用特定的监督学习重新校准骨干网络与病变检测的下游任务。所提出的方法是用来自四个供应商的乳房X线照片和一个看不见的公共数据集进行评估。实验结果表明，我们的方法可以有效地改善观察和看不见的域的检测性能，并且优于许多最先进的（SOTA）泛化方法。

Panoptic Part Segmentation (PPS) unifies panoptic segmentation and part segmentation into one task. Previous works utilize separated approaches to handle thing, stuff, and part predictions without shared computation and task association. We aim to unify these tasks at the architectural level, designing the first end-to-end unified framework named Panoptic-PartFormer. Moreover, we find the previous metric PartPQ biases to PQ. To handle both issues, we make the following contributions: Firstly, we design a meta-architecture that decouples part feature and things/stuff feature, respectively. We model things, stuff, and parts as object queries and directly learn to optimize all three forms of prediction as a unified mask prediction and classification problem. We term our model as Panoptic-PartFormer. Secondly, we propose a new metric Part-Whole Quality (PWQ) to better measure such task from both pixel-region and part-whole perspectives. It can also decouple the error for part segmentation and panoptic segmentation. Thirdly, inspired by Mask2Former, based on our meta-architecture, we propose Panoptic-PartFormer++ and design a new part-whole cross attention scheme to further boost part segmentation qualities. We design a new part-whole interaction method using masked cross attention. Finally, the extensive ablation studies and analysis demonstrate the effectiveness of both Panoptic-PartFormer and Panoptic-PartFormer++. Compared with previous Panoptic-PartFormer, our Panoptic-PartFormer++ achieves 2% PartPQ and 3% PWQ improvements on the Cityscapes PPS dataset and 5% PartPQ on the Pascal Context PPS dataset. On both datasets, Panoptic-PartFormer++ achieves new state-of-the-art results with a significant cost drop of 70% on GFlops and 50% on parameters. Our models can serve as a strong baseline and aid future research in PPS. Code will be available.

Rankings are widely collected in various real-life scenarios, leading to the leakage of personal information such as users' preferences on videos or news. To protect rankings, existing works mainly develop privacy protection on a single ranking within a set of ranking or pairwise comparisons of a ranking under the $\epsilon$-differential privacy. This paper proposes a novel notion called $\epsilon$-ranking differential privacy for protecting ranks. We establish the connection between the Mallows model (Mallows, 1957) and the proposed $\epsilon$-ranking differential privacy. This allows us to develop a multistage ranking algorithm to generate synthetic rankings while satisfying the developed $\epsilon$-ranking differential privacy. Theoretical results regarding the utility of synthetic rankings in the downstream tasks, including the inference attack and the personalized ranking tasks, are established. For the inference attack, we quantify how $\epsilon$ affects the estimation of the true ranking based on synthetic rankings. For the personalized ranking task, we consider varying privacy preferences among users and quantify how their privacy preferences affect the consistency in estimating the optimal ranking function. Extensive numerical experiments are carried out to verify the theoretical results and demonstrate the effectiveness of the proposed synthetic ranking algorithm.

In this work, we focus on instance-level open vocabulary segmentation, intending to expand a segmenter for instance-wise novel categories without mask annotations. We investigate a simple yet effective framework with the help of image captions, focusing on exploiting thousands of object nouns in captions to discover instances of novel classes. Rather than adopting pretrained caption models or using massive caption datasets with complex pipelines, we propose an end-to-end solution from two aspects: caption grounding and caption generation. In particular, we devise a joint Caption Grounding and Generation (CGG) framework based on a Mask Transformer baseline. The framework has a novel grounding loss that performs explicit and implicit multi-modal feature alignments. We further design a lightweight caption generation head to allow for additional caption supervision. We find that grounding and generation complement each other, significantly enhancing the segmentation performance for novel categories. We conduct extensive experiments on the COCO dataset with two settings: Open Vocabulary Instance Segmentation (OVIS) and Open Set Panoptic Segmentation (OSPS). The results demonstrate the superiority of our CGG framework over previous OVIS methods, achieving a large improvement of 6.8% mAP on novel classes without extra caption data. Our method also achieves over 15% PQ improvements for novel classes on the OSPS benchmark under various settings.

Temporal sentence grounding (TSG) aims to identify the temporal boundary of a specific segment from an untrimmed video by a sentence query. All existing works first utilize a sparse sampling strategy to extract a fixed number of video frames and then conduct multi-modal interactions with query sentence for reasoning. However, we argue that these methods have overlooked two indispensable issues: 1) Boundary-bias: The annotated target segment generally refers to two specific frames as corresponding start and end timestamps. The video downsampling process may lose these two frames and take the adjacent irrelevant frames as new boundaries. 2) Reasoning-bias: Such incorrect new boundary frames also lead to the reasoning bias during frame-query interaction, reducing the generalization ability of model. To alleviate above limitations, in this paper, we propose a novel Siamese Sampling and Reasoning Network (SSRN) for TSG, which introduces a siamese sampling mechanism to generate additional contextual frames to enrich and refine the new boundaries. Specifically, a reasoning strategy is developed to learn the inter-relationship among these frames and generate soft labels on boundaries for more accurate frame-query reasoning. Such mechanism is also able to supplement the absent consecutive visual semantics to the sampled sparse frames for fine-grained activity understanding. Extensive experiments demonstrate the effectiveness of SSRN on three challenging datasets.

Brain midline shift (MLS) is one of the most critical factors to be considered for clinical diagnosis and treatment decision-making for intracranial hemorrhage. Existing computational methods on MLS quantification not only require intensive labeling in millimeter-level measurement but also suffer from poor performance due to their dependence on specific landmarks or simplified anatomical assumptions. In this paper, we propose a novel semi-supervised framework to accurately measure the scale of MLS from head CT scans. We formulate the MLS measurement task as a deformation estimation problem and solve it using a few MLS slices with sparse labels. Meanwhile, with the help of diffusion models, we are able to use a great number of unlabeled MLS data and 2793 non-MLS cases for representation learning and regularization. The extracted representation reflects how the image is different from a non-MLS image and regularization serves an important role in the sparse-to-dense refinement of the deformation field. Our experiment on a real clinical brain hemorrhage dataset has achieved state-of-the-art performance and can generate interpretable deformation fields.

It is crucial to evaluate the quality and determine the optimal number of clusters in cluster analysis. In this paper, the multi-granularity characterization of the data set is carried out to obtain the hyper-balls. The cluster internal evaluation index based on hyper-balls(HCVI) is defined. Moreover, a general method for determining the optimal number of clusters based on HCVI is proposed. The proposed methods can evaluate the clustering results produced by the several classic methods and determine the optimal cluster number for data sets containing noises and clusters with arbitrary shapes. The experimental results on synthetic and real data sets indicate that the new index outperforms existing ones.

Normalizing flow is a class of deep generative models for efficient sampling and density estimation. In practice, the flow often appears as a chain of invertible neural network blocks; to facilitate training, existing works have regularized flow trajectories and designed special network architectures. The current paper develops a neural ODE flow network inspired by the Jordan-Kinderleherer-Otto (JKO) scheme, which allows efficient block-wise training of the residual blocks and avoids inner loops of score matching or variational learning. As the JKO scheme unfolds the dynamic of gradient flow, the proposed model naturally stacks residual network blocks one-by-one, reducing the memory load and difficulty of performing end-to-end training of deep flow networks. We also develop adaptive time reparameterization of the flow network with a progressive refinement of the trajectory in probability space, which improves the model training efficiency and accuracy in practice. Using numerical experiments with synthetic and real data, we show that the proposed JKO-iFlow model achieves similar or better performance in generating new samples compared with existing flow and diffusion models at a significantly reduced computational and memory cost.