我们提出了一种有效的神经邻域搜索（N2S），以解决取货和交付问题（PDPS）。具体而言，我们设计了强大的综合注意力，可以使香草自我注意力综合有关路线解决方案的各种特征。我们还利用了两个自定义的解码器，它们会自动学习执行拾取节点对的删除和重新插入以应对优先限制。此外，利用多样性增强方案以进一步改善性能。我们的N2是通用的，并且对两个规范PDP变体进行了广泛的实验表明，它可以在现有神经方法之间产生最新的结果。此外，它甚至超过了众所周知的LKH3求解器在更受限的PDP变体上。我们针对N2S的实施可在线获得。

The growing literature of Federated Learning (FL) has recently inspired Federated Reinforcement Learning (FRL) to encourage multiple agents to federatively build a better decision-making policy without sharing raw trajectories. Despite its promising applications, existing works on FRL fail to I) provide theoretical analysis on its convergence, and II) account for random system failures and adversarial attacks. Towards this end, we propose the first FRL framework the convergence of which is guaranteed and tolerant to less than half of the participating agents being random system failures or adversarial attackers. We prove that the sample efficiency of the proposed framework is guaranteed to improve with the number of agents and is able to account for such potential failures or attacks. All theoretical results are empirically verified on various RL benchmark tasks.

最近，变压器已成为解决车辆路由问题（VRP）的盛行深度建筑。但是，它在学习VRP的学习改进模型方面的有效性较小，因为其位置编码（PE）方法不适合表示VRP解决方案。本文介绍了一种新颖的双重协作变压器（DACT），以分别学习节点和位置特征的嵌入，而不是像现有的那样将它们融合在一起，以避免潜在的噪音和不相容的相关性。此外，位置特征通过新型的循环位置编码（CPE）方法嵌入，以使变压器有效捕获VRP溶液（即环状序列）的圆形性和对称性。我们使用近端政策优化训练DACT，并设计一种课程学习策略，以提高样本效率。我们应用DACT来解决旅行推销员问题（TSP）和电容的车辆路由问题（CVRP）。结果表明，我们的DACT优于现有的基于变压器的改进模型，并且在合成和基准实例上分别在不同问题大小上表现出更好的概括性能。

域泛化旨在通过来自有限数量的培训环境的数据表现良好。尽管这项任务提出了提案算法，但理论上和经验仍然非常具有挑战性的评估其表现。分类匹配算法，如（条件）域对抗网络[Ganin等，2016，Long等人，2018]是流行的，享受经验的成功，但缺乏正式的保证。其他诸如不变风险最小化（IRM）的方法需要一定大量的大量培训环境 - 在虚假的特征空间的维度中，即使在[Rosenfeld等人是否提出的简单数据模型， 2021]。在该模型的变种下，我们表明，ERM和IRM都不能以$ O（d_s）$环境概括。然后，我们提出了一种迭代特征匹配算法，其保证具有高概率，以产生推广在仅看到$ O（\ log d_s）$环境之后推广的预测器。我们的结果为在具体的非竞争数据模型下，广泛使用的分销匹配算法系列提供了第一理论理由。

In this paper, a semantic communication framework for image transmission is developed. In the investigated framework, a set of servers cooperatively transmit images to a set of users utilizing semantic communication techniques. To evaluate the performance of studied semantic communication system, a multimodal metric is proposed to measure the correlation between the extracted semantic information and the original image. To meet the ISS requirement of each user, each server must jointly determine the semantic information to be transmitted and the resource blocks (RBs) used for semantic information transmission. We formulate this problem as an optimization problem aiming to minimize each server's transmission latency while reaching the ISS requirement. To solve this problem, a value decomposition based entropy-maximized multi-agent reinforcement learning (RL) is proposed, which enables servers to coordinate for training and execute RB allocation in a distributed manner to approach to a globally optimal performance with less training iterations. Compared to traditional multi-agent RL, the proposed RL improves the valuable action exploration of servers and the probability of finding a globally optimal RB allocation policy based on local observation. Simulation results show that the proposed algorithm can reduce the transmission delay by up to 16.1% compared to traditional multi-agent RL.

Decentralized bilevel optimization has received increasing attention recently due to its foundational role in many emerging multi-agent learning paradigms (e.g., multi-agent meta-learning and multi-agent reinforcement learning) over peer-to-peer edge networks. However, to work with the limited computation and communication capabilities of edge networks, a major challenge in developing decentralized bilevel optimization techniques is to lower sample and communication complexities. This motivates us to develop a new decentralized bilevel optimization called DIAMOND (decentralized single-timescale stochastic approximation with momentum and gradient-tracking). The contributions of this paper are as follows: i) our DIAMOND algorithm adopts a single-loop structure rather than following the natural double-loop structure of bilevel optimization, which offers low computation and implementation complexity; ii) compared to existing approaches, the DIAMOND algorithm does not require any full gradient evaluations, which further reduces both sample and computational complexities; iii) through a careful integration of momentum information and gradient tracking techniques, we show that the DIAMOND algorithm enjoys $\mathcal{O}(\epsilon^{-3/2})$ in sample and communication complexities for achieving an $\epsilon$-stationary solution, both of which are independent of the dataset sizes and significantly outperform existing works. Extensive experiments also verify our theoretical findings.

In the field of antibody engineering, an essential task is to design a novel antibody whose paratopes bind to a specific antigen with correct epitopes. Understanding antibody structure and its paratope can facilitate a mechanistic understanding of its function. Therefore, antibody structure prediction from its sequence alone has always been a highly valuable problem for de novo antibody design. AlphaFold2, a breakthrough in the field of structural biology, provides a solution to predict protein structure based on protein sequences and computationally expensive coevolutionary multiple sequence alignments (MSAs). However, the computational efficiency and undesirable prediction accuracy of antibodies, especially on the complementarity-determining regions (CDRs) of antibodies limit their applications in the industrially high-throughput drug design. To learn an informative representation of antibodies, we employed a deep antibody language model (ALM) on curated sequences from the observed antibody space database via a transformer model. We also developed a novel model named xTrimoABFold to predict antibody structure from antibody sequence based on the pretrained ALM as well as efficient evoformers and structural modules. The model was trained end-to-end on the antibody structures in PDB by minimizing the ensemble loss of domain-specific focal loss on CDR and the frame-aligned point loss. xTrimoABFold outperforms AlphaFold2 and other protein language model based SOTAs, e.g., OmegaFold, HelixFold-Single, and IgFold with a large significant margin (30+\% improvement on RMSD) while performing 151 times faster than AlphaFold2. To the best of our knowledge, xTrimoABFold achieved state-of-the-art antibody structure prediction. Its improvement in both accuracy and efficiency makes it a valuable tool for de novo antibody design and could make further improvements in immuno-theory.

While large pre-trained models have transformed the field of natural language processing (NLP), the high training cost and low cross-lingual availability of such models prevent the new advances from being equally shared by users across all languages, especially the less spoken ones. To promote equal opportunities for all language speakers in NLP research and to reduce energy consumption for sustainability, this study proposes an effective and energy-efficient framework GreenPLM that uses bilingual lexicons to directly translate language models of one language into other languages at (almost) no additional cost. We validate this approach in 18 languages and show that this framework is comparable to, if not better than, other heuristics trained with high cost. In addition, when given a low computational cost (2.5\%), the framework outperforms the original monolingual language models in six out of seven tested languages. We release language models in 50 languages translated from English and the source code here.

Covid-19-Pandemic继续在社交媒体上提出各种讨论或辩论的主题。为了探索大流行对人们生活的影响，了解公众对与大流行有关的实体（例如药物，疫苗）对社交媒体的关注和态度至关重要。但是，对现有命名实体识别（NER）或目标情感分析（TSA）数据集培训的模型具有有限的理解与COVID相关的社交媒体文本的能力有限，因为这些数据集并未从医学角度设计或注释。本文释放了Mets-COV，这是一种包含医疗实体的数据集和与COVID相关的推文中的目标情感。 Mets-COV包含10,000条带有7种实体的推文，包括4种医疗实体类型（疾病，药物，症状和疫苗）和3种通用实体类型（人，位置和组织）。为了进一步调查推文用户对特定实体的态度，选择了4种类型的实体（人，组织，药物和疫苗），并用用户情感注释，从而产生了具有9,101个实体（5,278个推文）的目标情感数据集。据我们所知，METS-COV是第一个收集与COVID相关推文的医疗实体和相应情感的数据集。我们通过广泛的实验对经典机器学习模型和最先进的深度学习模型进行基准测试。结果表明，该数据集在NER和TSA任务方面都有大量改进的空间。 METS-COV是开发更好的医学社交媒体工具并促进计算社会科学研究的重要资源，尤其是在流行病学方面。我们的数据，注释准则，基准模型和源代码公开可用（https://github.com/ylab-open/mets-cov），以确保可重复性。

美国的意识形态分裂在日常交流中变得越来越突出。因此，关于政治两极分化的许多研究，包括最近采取计算观点的许多努力。通过检测文本语料库中的政治偏见，可以尝试描述和辨别该文本的两极分性。从直觉上讲，命名的实体（即，用作名词的名词和短语）和文本中的标签经常带有有关政治观点的信息。例如，使用“支持选择”一词的人可能是自由的，而使用“亲生生命”一词的人可能是保守的。在本文中，我们试图揭示社交媒体文本数据中的政治极性，并通过将极性得分分配给实体和标签来量化这些极性。尽管这个想法很简单，但很难以可信赖的定量方式进行这种推论。关键挑战包括少数已知标签，连续的政治观点，以及在嵌入单词媒介中的极性得分和极性中性语义含义的保存。为了克服这些挑战，我们提出了极性感知的嵌入多任务学习（PEM）模型。该模型包括（1）自制的上下文保护任务，（2）基于注意力的推文级别的极性推导任务，以及（3）对抗性学习任务，可促进嵌入式的极性维度及其语义之间的独立性方面。我们的实验结果表明，我们的PEM模型可以成功学习极性感知的嵌入。我们检查了各种应用，从而证明了PEM模型的有效性。我们还讨论了我们的工作的重要局限性，并在将PEM模型应用于现实世界情景时的压力谨慎。