检测小物体是阻碍对象检测开发的主要障碍之一。通用对象检测器的性能在微小的对象检测任务上往往会大大恶化。在本文中，我们指出的是，基于锚的检测器中的先验盒或无锚检测器中的点是微小对象的优化。我们的主要观察结果是，当前基于锚的或无锚的标签分配范例将引起许多离群的微小地面真实样本，从而导致检测器对小物体的关注较少。为此，我们提出了一个基于高斯接受场的标签分配（RFLA）策略，以进行微小的对象检测。具体而言，RFLA首先利用了特征接受场遵循高斯分布的先前信息。然后，提出了一个新的接受场距离（RFD），而不是通过IOU或中心采样策略分配样品，以直接测量高斯接受场和地面真相之间的相似性。考虑到基于阈值的和中心的采样策略偏向大物体，我们进一步设计了基于RFD的层次标签分配（HLA）模块，以实现微小对象的平衡学习。四个数据集上的广泛实验证明了所提出的方法的有效性。尤其是，我们的方法在AI-TOD数据集上以4.0 AP点优于最先进的竞争对手。代码可从https://github.com/chasel-tsui/mmdet-rfla获得

航空图像中的微小对象检测（TOD）是具有挑战性的，因为一个小物体只包含几个像素。最先进的对象探测器由于缺乏判别特征的监督而无法为微小对象提供令人满意的结果。我们的主要观察结果是，联合度量（IOU）及其扩展的相交对微小物体的位置偏差非常敏感，这在基于锚固的探测器中使用时会大大恶化标签分配的质量。为了解决这个问题，我们提出了一种新的评估度量标准，称为标准化的Wasserstein距离（NWD）和一个新的基于排名的分配（RKA）策略，以进行微小对象检测。提出的NWD-RKA策略可以轻松地嵌入到各种基于锚的探测器中，以取代标准的基于阈值的检测器，从而大大改善了标签分配并为网络培训提供了足够的监督信息。在四个数据集中测试，NWD-RKA可以始终如一地提高微小的对象检测性能。此外，在空中图像（AI-TOD）数据集中观察到显着的嘈杂标签，我们有动力将其重新标记并释放AI-TOD-V2及其相应的基准。在AI-TOD-V2中，丢失的注释和位置错误问题得到了大大减轻，从而促进了更可靠的培训和验证过程。将NWD-RKA嵌入探测器中，检测性能比AI-TOD-V2上的最先进竞争对手提高了4.3个AP点。数据集，代码和更多可视化可在以下网址提供：https：//chasel-tsui.g​​ithub.io/ai/ai-tod-v2/

检测微小的物体是一个非常具有挑战性的问题，因为一个小物体只包含几个像素的大小。我们证明，由于缺乏外观信息，最新的检测器不会对微小物体产生令人满意的结果。我们的主要观察结果是，基于联合（IOU）的相交（例如IOU本身及其扩展）对微小物体的位置偏差非常敏感，并且在基于锚固的检测器中使用时会大大恶化检测性能。为了减轻这一点，我们提出了使用Wasserstein距离进行微小对象检测的新评估度量。具体而言，我们首先将边界框建模为2D高斯分布，然后提出一个新的公制称为标准化的瓦斯汀距离（NWD），以通过相应的高斯分布来计算它们之间的相似性。提出的NWD度量可以轻松地嵌入分配中，非最大抑制作用以及任何基于锚固的检测器的损耗函数，以替换常用的IOU度量。我们在新的数据集上评估了我们的度量，以用于微小对象检测（AI-TOD），其中平均对象大小比现有对象检测数据集小得多。广泛的实验表明，在配备NWD指标时，我们的方法的性能比标准的微调基线高6.7 AP点，并且比最先进的竞争对手高6.0 AP点。代码可在以下网址提供：https：//github.com/jwwangchn/nwd。

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.

This paper focuses on designing efficient models with low parameters and FLOPs for dense predictions. Even though CNN-based lightweight methods have achieved stunning results after years of research, trading-off model accuracy and constrained resources still need further improvements. This work rethinks the essential unity of efficient Inverted Residual Block in MobileNetv2 and effective Transformer in ViT, inductively abstracting a general concept of Meta-Mobile Block, and we argue that the specific instantiation is very important to model performance though sharing the same framework. Motivated by this phenomenon, we deduce a simple yet efficient modern \textbf{I}nverted \textbf{R}esidual \textbf{M}obile \textbf{B}lock (iRMB) for mobile applications, which absorbs CNN-like efficiency to model short-distance dependency and Transformer-like dynamic modeling capability to learn long-distance interactions. Furthermore, we design a ResNet-like 4-phase \textbf{E}fficient \textbf{MO}del (EMO) based only on a series of iRMBs for dense applications. Massive experiments on ImageNet-1K, COCO2017, and ADE20K benchmarks demonstrate the superiority of our EMO over state-of-the-art methods, \eg, our EMO-1M/2M/5M achieve 71.5, 75.1, and 78.4 Top-1 that surpass \textbf{SoTA} CNN-/Transformer-based models, while trading-off the model accuracy and efficiency well.

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.

Benefiting from the intrinsic supervision information exploitation capability, contrastive learning has achieved promising performance in the field of deep graph clustering recently. However, we observe that two drawbacks of the positive and negative sample construction mechanisms limit the performance of existing algorithms from further improvement. 1) The quality of positive samples heavily depends on the carefully designed data augmentations, while inappropriate data augmentations would easily lead to the semantic drift and indiscriminative positive samples. 2) The constructed negative samples are not reliable for ignoring important clustering information. To solve these problems, we propose a Cluster-guided Contrastive deep Graph Clustering network (CCGC) by mining the intrinsic supervision information in the high-confidence clustering results. Specifically, instead of conducting complex node or edge perturbation, we construct two views of the graph by designing special Siamese encoders whose weights are not shared between the sibling sub-networks. Then, guided by the high-confidence clustering information, we carefully select and construct the positive samples from the same high-confidence cluster in two views. Moreover, to construct semantic meaningful negative sample pairs, we regard the centers of different high-confidence clusters as negative samples, thus improving the discriminative capability and reliability of the constructed sample pairs. Lastly, we design an objective function to pull close the samples from the same cluster while pushing away those from other clusters by maximizing and minimizing the cross-view cosine similarity between positive and negative samples. Extensive experimental results on six datasets demonstrate the effectiveness of CCGC compared with the existing state-of-the-art algorithms.