在本文中，我们介绍了CTC 2021的概述，这是针对母语人士的中文文本校正任务。我们详细描述了任务定义以及培训和评估的数据。我们还总结了该任务参与者调查的方法。我们希望为此任务收集和注释的数据集可以促进并加快该研究领域的未来发展。因此，伪培训数据，金标准验证数据和整个排行榜可在https://destwang.github.io/ctc2021-explorer/上在线公开获取。

基于AI的蛋白质结构预测管道（例如AlphaFold2）已达到了几乎实验的准确性。这些高级管道主要依赖于多个序列比对（MSA）和模板作为输入来从同源序列中学习共进化信息。但是，从蛋白质数据库中搜索MSA和模板很耗时，通常需要数十分钟。因此，我们尝试通过仅使用蛋白质的主要序列来探索快速蛋白质结构预测的极限。提出了Helixfold单一的形式将大规模蛋白质语言模型与AlphaFold2的优质几何学习能力相结合。我们提出的方法，Helixfold单个，首先预先培训是一种大规模蛋白质语言模型（PLM），使用了数以千计的主要序列利用自我监督的学习范式，将用作MSA和模板的替代方法共同进化信息。然后，通过将预训练的PLM和AlphaFold2的必需组件组合在一起，我们获得了一个端到端可区分模型，以仅从主要序列预测原子的3D坐标。 Helixfold-Single在数据集CASP14和Cameo中得到了验证，通过基于MSA的方法，具有大型同源家庭的基于MSA的方法，从而实现了竞争精度。此外，与主流管道进行蛋白质结构预测相比，Helixfold单个的时间比主流管道的时间少得多，这表明其在需要许多预测的任务中的潜力。 HelixFold-Single的守则可在https://github.com/paddlepaddle/paddlehelix/tree/dev/dev/pprotein_folding/helixfold-single上获得，我们还在https://paddlehelix.baidu.com上提供稳定的Web服务。 /app/drug/protein-single/prevast。

多语言预训练的语言模型在跨语言任务上表现出了令人印象深刻的表现。它极大地促进了自然语言处理在低资源语言上的应用。但是，当前的多语言模型仍然有些语言表现不佳。在本文中，我们提出了Cino（中国少数族裔训练的语言模型），这是一种用于中国少数语言的多语言预训练的语言模型。它涵盖了标准的中文，Yue中文和其他六种少数民族语言。为了评估多语言模型在少数族裔语言上的跨语性能力，我们从Wikipedia和新闻网站收集文档，并构建两个文本分类数据集，WCM（Wiki-Chinese-Minority）和CMNEWS（中国最少的新闻）。我们表明，Cino在各种分类任务上的表现明显优于基准。Cino模型和数据集可在http://cino.hfl-rc.com上公开获得。

Knowledge graph embedding (KGE) models learn the representation of entities and relations in knowledge graphs. Distance-based methods show promising performance on link prediction task, which predicts the result by the distance between two entity representations. However, most of these methods represent the head entity and tail entity separately, which limits the model capacity. We propose two novel distance-based methods named InterHT and InterHT+ that allow the head and tail entities to interact better and get better entity representation. Experimental results show that our proposed method achieves the best results on ogbl-wikikg2 dataset.

Reinforcement learning (RL) is one of the most important branches of AI. Due to its capacity for self-adaption and decision-making in dynamic environments, reinforcement learning has been widely applied in multiple areas, such as healthcare, data markets, autonomous driving, and robotics. However, some of these applications and systems have been shown to be vulnerable to security or privacy attacks, resulting in unreliable or unstable services. A large number of studies have focused on these security and privacy problems in reinforcement learning. However, few surveys have provided a systematic review and comparison of existing problems and state-of-the-art solutions to keep up with the pace of emerging threats. Accordingly, we herein present such a comprehensive review to explain and summarize the challenges associated with security and privacy in reinforcement learning from a new perspective, namely that of the Markov Decision Process (MDP). In this survey, we first introduce the key concepts related to this area. Next, we cover the security and privacy issues linked to the state, action, environment, and reward function of the MDP process, respectively. We further highlight the special characteristics of security and privacy methodologies related to reinforcement learning. Finally, we discuss the possible future research directions within this area.

青光眼是一种严重的盲目疾病，迫切需要自动检测方法来减轻眼科医生的稀缺性。许多作品提出采用深度学习方法，涉及视盘和杯中的分割以进行青光眼检测，其中分割过程通常仅被视为上游子任务。在青光眼评估中，底底图像与分割面具之间的关系很少探索。我们提出了一种基于细分的信息提取和融合方法来实现青光眼检测任务，该方法利用了分割掩模的稳健性，而无需忽略原始底底图像中的丰富信息。私有数据集和公共数据集的实验结果表明，我们提出的方法的表现优于所有仅利用底面图像或口罩的模型。

对于视网膜图像匹配（RIM），我们提出了SuperRetina，这是第一个具有可训练的键盘检测器和描述符的端到端方法。 SuperRetina以一种新颖的半监督方式接受了训练。一小部分（近100张）图像未完全标记，并用于监督网络以检测血管树上的关键点。为了攻击手动标记的不完整性，我们提出了进行性逐步扩展，以丰富每个训练时期的关键点标签。通过利用基于关键的改进的三重态损失作为描述损失，超级逆局以完全输入图像大小产生高度歧视性描述符。在多个现实世界数据集上进行了广泛的实验证明了超级丽菌的生存能力。即使手动标记被自动标记取代，因此使训练过程完全免费手动通道，超级retina也可以与多个强大的基线进行比较，以进行两个RIM任务，即图像注册和身份验证。 SuperRetina将是开源。

点云的语义分割，旨在为每个点分配语义类别，对3D场景的理解至关重要。尽管近年来取得了重大进展，但大多数现有方法仍然遭受对象级别的错误分类或边界级别的歧义。在本文中，我们通过深入探索被称为Geosegnet的点云的几何形状来提出一个强大的语义分割网络。我们的Geosegnet由一个基于多几何的编码器和边界引导的解码器组成。在编码器中，我们从多几何的角度开发了一个新的残差几何模块，以提取对象级特征。在解码器中，我们引入了一个对比边界学习模块，以增强边界点的几何表示。从几何编码器模型中受益，我们的GEOSEGNET可以在使两个或多个对象的相交（边界）清晰地确定对象的分割。从总体分割精度和对象边界清除方面，实验显示了我们方法对竞争对手的明显改善。代码可在https://github.com/chen-yuiyui/geosegnet上找到。

Planning is one of the main approaches used to improve agents' working efficiency by making plans beforehand. However, during planning, agents face the risk of having their private information leaked. This paper proposes a novel strong privacy-preserving planning approach for logistic-like problems. This approach outperforms existing approaches by addressing two challenges: 1) simultaneously achieving strong privacy, completeness and efficiency, and 2) addressing communication constraints. These two challenges are prevalent in many real-world applications including logistics in military environments and packet routing in networks. To tackle these two challenges, our approach adopts the differential privacy technique, which can both guarantee strong privacy and control communication overhead. To the best of our knowledge, this paper is the first to apply differential privacy to the field of multi-agent planning as a means of preserving the privacy of agents for logistic-like problems. We theoretically prove the strong privacy and completeness of our approach and empirically demonstrate its efficiency. We also theoretically analyze the communication overhead of our approach and illustrate how differential privacy can be used to control it.

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.