计算机辅助诊断（CAD）系统可以为皮肤病的临床诊断提供参考。卷积神经网络（CNN）不仅可以提取视觉元素，例如颜色和形状，而且还可以提取语义特征。因此，他们在皮肤镜检查图像的许多任务中取得了重大改进。皮肤镜检查的成像没有主要方向，表明数据集中有大量的皮肤病变靶旋转。然而，CNN缺乏抗旋转能力，这必然会影响CNN的特征提取能力。我们提出了一个旋转平均值（RM）网络，以从皮肤镜图像中提取旋转不变性特征。在RM中，每组旋转的特征地图对应于一组重量共享卷积输出，并使用MeanOut操作融合以获取最终特征图。通过理论推导，提出的RM网络是旋转等值的，并且在全球平均池（GAP）操作之后，可以提取旋转不变的特征。提取的旋转不变特征可以更好地代表皮肤镜图像的分类和检索任务中的原始数据。提出的RM是一般操作，它不会改变网络结构或增加任何参数，并且可以灵活地嵌入CNN的任何部分。大量实验是在皮肤镜检查图像数据集上进行的。结果表明，我们的方法优于其他抗旋转方法，并在皮肤镜检查图像分类和检索任务方面取得了重大改进，表明在皮肤镜图像领域旋转不变性的潜力。

Label smoothing is a regularization technique widely used in supervised learning to improve the generalization of models on various tasks, such as image classification and machine translation. However, the effectiveness of label smoothing in multi-hop question answering (MHQA) has yet to be well studied. In this paper, we systematically analyze the role of label smoothing on various modules of MHQA and propose F1 smoothing, a novel label smoothing technique specifically designed for machine reading comprehension (MRC) tasks. We evaluate our method on the HotpotQA dataset and demonstrate its superiority over several strong baselines, including models that utilize complex attention mechanisms. Our results suggest that label smoothing can be effective in MHQA, but the choice of smoothing strategy can significantly affect performance.

游戏理论到目前为止在各个领域都发现了许多应用，包括经济学，工业，法学和人工智能，每个玩家都只关心自己对非合作或合作方式的兴趣，但对其他玩家没有明显的恶意。但是，在许多实际应用中，例如扑克，国际象棋，逃避者追求，毒品拦截，海岸警卫队，网络安全和国防，球员通常都具有对抗性立场，也就是说，每个球员的自私行动不可避免地或故意造成损失或对其他球员造成严重破坏。沿着这条线，本文对在对抗性游戏中广泛使用的三种主要游戏模型（即零和零正常形式和广泛形式游戏，stackelberg（Security）游戏，零和差异游戏）提供了系统的调查。观点，包括游戏模型的基本知识，（近似）平衡概念，问题分类，研究前沿，（近似）最佳策略寻求技术，普遍的算法和实际应用。最后，还讨论了有关对抗性游戏的有希望的未来研究方向。

提出了一种基于深度学习的模型减少（DeepMR）用于简化化学动力学的方法，并使用高温自动点火，完全搅拌反应器（PSR）和一维自由传播的正庚烷/空气混合物的一致性。减少机制被建模为布尔空间的优化问题，其中布尔向量，与物种对应的每个条目表示减少的机制。优化目标是最小化给定考虑到一组预选的基准量的误差的机制尺寸。 DeepMR的关键思想是使用深度神经网络（DNN）来制定优化问题中的目标函数。为了有效地探索高维布尔空间，实现了一种迭代的DNN辅助数据采样和DNN训练过程。结果表明，DNN辅助显着提高了采样效率，仅为10 ^ {34}美元的样本中选择了10 ^ 5美元的样品，以实现足够的准确性。结果证明了DNN识别关键物种的能力，合理预测机制性能降低。训练有素的DNN通过解决反向优化问题，保证了最佳减少的机制。通过比较点火延迟时间，Laminar火焰速度，PSR的温度，得到的骨骼机制具有更少的物种（45种），但与通过路径通量分析（PFA）方法获得的骨骼机制（56种）相同的精度水平。另外，如果仅考虑大气，近化学计量条件（0.6和1.2之间的等效比），则骨骼机构可以进一步减少到28种。 DeepMR提供了一种进行模型减少的创新方法，并演示了燃烧区域中数据驱动方法的巨大潜力。

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.

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.

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.

Given the increasingly intricate forms of partial differential equations (PDEs) in physics and related fields, computationally solving PDEs without analytic solutions inevitably suffers from the trade-off between accuracy and efficiency. Recent advances in neural operators, a kind of mesh-independent neural-network-based PDE solvers, have suggested the dawn of overcoming this challenge. In this emerging direction, Koopman neural operator (KNO) is a representative demonstration and outperforms other state-of-the-art alternatives in terms of accuracy and efficiency. Here we present KoopmanLab, a self-contained and user-friendly PyTorch module of the Koopman neural operator family for solving partial differential equations. Beyond the original version of KNO, we develop multiple new variants of KNO based on different neural network architectures to improve the general applicability of our module. These variants are validated by mesh-independent and long-term prediction experiments implemented on representative PDEs (e.g., the Navier-Stokes equation and the Bateman-Burgers equation) and ERA5 (i.e., one of the largest high-resolution data sets of global-scale climate fields). These demonstrations suggest the potential of KoopmanLab to be considered in diverse applications of partial differential equations.

A recent study has shown a phenomenon called neural collapse in that the within-class means of features and the classifier weight vectors converge to the vertices of a simplex equiangular tight frame at the terminal phase of training for classification. In this paper, we explore the corresponding structures of the last-layer feature centers and classifiers in semantic segmentation. Based on our empirical and theoretical analysis, we point out that semantic segmentation naturally brings contextual correlation and imbalanced distribution among classes, which breaks the equiangular and maximally separated structure of neural collapse for both feature centers and classifiers. However, such a symmetric structure is beneficial to discrimination for the minor classes. To preserve these advantages, we introduce a regularizer on feature centers to encourage the network to learn features closer to the appealing structure in imbalanced semantic segmentation. Experimental results show that our method can bring significant improvements on both 2D and 3D semantic segmentation benchmarks. Moreover, our method ranks 1st and sets a new record (+6.8% mIoU) on the ScanNet200 test leaderboard. Code will be available at https://github.com/dvlab-research/Imbalanced-Learning.

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.