时空表示学习对于视频自我监督的表示至关重要。最近的方法主要使用对比学习和借口任务。然而，这些方法通过在潜在空间中的特征相似性判断所学习表示的中间状态的同时通过潜伏空间中的特征相似性来学习表示，这限制了整体性能。在这项工作中，考虑到采样实例的相似性作为中级状态，我们提出了一种新的借口任务 - 时空 - 时间重叠速率（Stor）预测。它源于观察到，人类能够区分空间和时间在视频中的重叠率。此任务鼓励模型区分两个生成的样本的存储来学习表示。此外，我们采用了联合优化，将借口任务与对比学习相结合，以进一步增强时空表示学习。我们还研究了所提出的计划中每个组分的相互影响。广泛的实验表明，我们的拟议Stor任务可以赞成对比学习和借口任务。联合优化方案可以显着提高视频理解中的时空表示。代码可在https://github.com/katou2/cstp上获得。

作为计算机视觉的基本任务，图像相似性检索正面临大规模数据和图像复制攻击的挑战。本文介绍了由Facebook AI组织的图像相似性挑战（ISC）2021的匹配轨道的第3个解决方案。我们提出了一种组合全局描述符和本地描述符的多分支检索方法来覆盖所有攻击案例。具体而言，我们尝试了许多策略来优化全局描述符，包括丰富的数据增强，具有单个变压器模型的自我监督学习，覆盖检测预处理。此外，我们介绍了稳健的SIFT功能和GPU Faiss，用于局部检索，弥补了全球检索的缺点。最后，knn匹配算法用于判断匹配和合并分数。我们展示了我们的方法的一些消融实验，揭示了全球和局部特征的互补优势。

深度神经网络容易受到对抗的例子，这可以通过添加微妙的扰动来欺骗深层模型。虽然现有的攻击已经取得了有希望的结果，但它仍然在黑盒设置下留下长途来产生可转移的对抗性示例。为此，本文提出提高对抗示例的可转移性，并将双阶段特征级扰动应用于现有模型，以隐式创建一组不同的模型。然后在迭代期间由纵向集合融合这些模型。该方法被称为双级网络侵蚀（DSNE）。我们对非残留和残余网络进行全面的实验，并获得更多可转移的对抗实例，其计算成本类似于最先进的方法。特别地，对于残余网络，通过将残余块信息偏置到跳过连接，可以显着改善对抗性示例的可转移性。我们的工作为神经网络的建筑脆弱性提供了新的见解，并对神经网络的稳健性带来了新的挑战。

非法车辆停车是世界上主要城市面临的常见城市问题，因为它导致空气污染和交通事故。政府高度依赖于积极的人类努力，以检测非法停车活动。然而，这种方法对于覆盖一个大城市来说，这一方法非常无效，因为警方必须巡逻整个城市道路。 Mobikike的大规模和高质量的共享自行车轨迹为我们提供了一个独特的机会，可以设计无处不在的非法停车检测方法，因为大多数非法停车处发生在路边，对自行车用户产生重大影响。检测结果可以指导巡逻计划，即将巡逻警察发送到具有更高的非法停车风险的地区，进一步提高巡逻效率。灵感来自这个想法，在建议的框架中采用了三个主要组件：1）〜{\ em轨迹预处理}，它过滤了异常GPS点，执行Map-匹配，并构建轨迹索引; 2）〜{\ em非法停车检测}，模拟正常轨迹，从评估轨迹提取特征，并利用基于试验的方法来发现非法停车事件; 3）〜{\ em巡逻计划}，它利用检测结果作为参考上下文，并将调度任务作为一种多智能体增强学习问题来指导巡逻警察。最后，提出了广泛的实验以验证非法停车检测的有效性，以及巡逻效率的提高。

对象攻击是对象检测的现实世界中可行的。然而，大多数以前的作品都试图学习应用于对象的本地“补丁”到愚蠢的探测器，这在斜视视角变得较低。为了解决这个问题，我们提出了致密的提案攻击（DPA）来学习探测器的单件，物理和针对性的对抗性伪装。伪装是一体的，因为它们是作为一个物体的整体生成的，因为当在任意观点和不同的照明条件下拍摄时，它们保持对抗性，并且由于它们可能导致探测器被定义为特定目标类别的检测器。为了使生成的伪装在物理世界中稳健，我们介绍了改造的组合来模拟物理现象。此外，为了改善攻击，DPA同时攻击固定建议中的所有分类。此外，我们使用Unity Simulation Engine构建虚拟3D场景，以公平地和可重复地评估不同的物理攻击。广泛的实验表明，DPA优于最先进的方法，并且对于任何物体而言，它是通用的，并且对现实世界的广泛性良好，对安全关键的计算机视觉系统构成潜在的威胁。

快速梯度标志攻击系列是用于生成对抗示例的流行方法。然而，基于快速梯度签名系列的大多数方法不能平衡由于基本标志结构的局限性而平衡的无法区分和可转换性。为了解决这个问题，我们提出了一种方法，称为ADAM迭代快速梯度Tanh方法（AI-FGTM），以产生具有高可转换性的无法区分的对抗性示例。此外，还施加较小的核和动态步长，以产生对攻击成功率的进一步提高攻击示例。在想象中兼容的数据集上的广泛实验表明，我们的方法在没有额外运行的时间和资源的情况下，我们的方法产生更加难以区分的对抗性示例并实现更高的攻击成功率。我们最佳的转移攻击Ni-Ti-Di-Aitm可以欺骗六种经典的防御模型，平均成功率为89.3％，三种先进的防御模型，平均成功率为82.7％，其高于国家基于艺术梯度的攻击。此外，我们的方法还可以减少近20％的平均扰动。我们预计我们的方法将作为一种新的基线，用于产生具有更好的转移性和无法区分的对抗性实例。

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.

Knowledge graphs (KG) have served as the key component of various natural language processing applications. Commonsense knowledge graphs (CKG) are a special type of KG, where entities and relations are composed of free-form text. However, previous works in KG completion and CKG completion suffer from long-tail relations and newly-added relations which do not have many know triples for training. In light of this, few-shot KG completion (FKGC), which requires the strengths of graph representation learning and few-shot learning, has been proposed to challenge the problem of limited annotated data. In this paper, we comprehensively survey previous attempts on such tasks in the form of a series of methods and applications. Specifically, we first introduce FKGC challenges, commonly used KGs, and CKGs. Then we systematically categorize and summarize existing works in terms of the type of KGs and the methods. Finally, we present applications of FKGC models on prediction tasks in different areas and share our thoughts on future research directions of FKGC.

Few Shot Instance Segmentation (FSIS) requires models to detect and segment novel classes with limited several support examples. In this work, we explore a simple yet unified solution for FSIS as well as its incremental variants, and introduce a new framework named Reference Twice (RefT) to fully explore the relationship between support/query features based on a Transformer-like framework. Our key insights are two folds: Firstly, with the aid of support masks, we can generate dynamic class centers more appropriately to re-weight query features. Secondly, we find that support object queries have already encoded key factors after base training. In this way, the query features can be enhanced twice from two aspects, i.e., feature-level and instance-level. In particular, we firstly design a mask-based dynamic weighting module to enhance support features and then propose to link object queries for better calibration via cross-attention. After the above steps, the novel classes can be improved significantly over our strong baseline. Additionally, our new framework can be easily extended to incremental FSIS with minor modification. When benchmarking results on the COCO dataset for FSIS, gFSIS, and iFSIS settings, our method achieves a competitive performance compared to existing approaches across different shots, e.g., we boost nAP by noticeable +8.2/+9.4 over the current state-of-the-art FSIS method for 10/30-shot. We further demonstrate the superiority of our approach on Few Shot Object Detection. Code and model will be available.

Graph Neural Networks (GNNs) have shown satisfying performance on various graph learning tasks. To achieve better fitting capability, most GNNs are with a large number of parameters, which makes these GNNs computationally expensive. Therefore, it is difficult to deploy them onto edge devices with scarce computational resources, e.g., mobile phones and wearable smart devices. Knowledge Distillation (KD) is a common solution to compress GNNs, where a light-weighted model (i.e., the student model) is encouraged to mimic the behavior of a computationally expensive GNN (i.e., the teacher GNN model). Nevertheless, most existing GNN-based KD methods lack fairness consideration. As a consequence, the student model usually inherits and even exaggerates the bias from the teacher GNN. To handle such a problem, we take initial steps towards fair knowledge distillation for GNNs. Specifically, we first formulate a novel problem of fair knowledge distillation for GNN-based teacher-student frameworks. Then we propose a principled framework named RELIANT to mitigate the bias exhibited by the student model. Notably, the design of RELIANT is decoupled from any specific teacher and student model structures, and thus can be easily adapted to various GNN-based KD frameworks. We perform extensive experiments on multiple real-world datasets, which corroborates that RELIANT achieves less biased GNN knowledge distillation while maintaining high prediction utility.