Advancements in reinforcement learning (RL) have inspired new directions in intelligent automation of network defense. However, many of these advancements have either outpaced their application to network security or have not considered the challenges associated with implementing them in the real-world. To understand these problems, this work evaluates several RL approaches implemented in the second edition of the CAGE Challenge, a public competition to build an autonomous network defender agent in a high-fidelity network simulator. Our approaches all build on the Proximal Policy Optimization (PPO) family of algorithms, and include hierarchical RL, action masking, custom training, and ensemble RL. We find that the ensemble RL technique performs strongest, outperforming our other models and taking second place in the competition. To understand applicability to real environments we evaluate each method's ability to generalize to unseen networks and against an unknown attack strategy. In unseen environments, all of our approaches perform worse, with degradation varied based on the type of environmental change. Against an unknown attacker strategy, we found that our models had reduced overall performance even though the new strategy was less efficient than the ones our models trained on. Together, these results highlight promising research directions for autonomous network defense in the real world.

Despite the central role that melody plays in music perception, it remains an open challenge in music information retrieval to reliably detect the notes of the melody present in an arbitrary music recording. A key challenge in melody transcription is building methods which can handle broad audio containing any number of instrument ensembles and musical styles - existing strategies work well for some melody instruments or styles but not all. To confront this challenge, we leverage representations from Jukebox (Dhariwal et al. 2020), a generative model of broad music audio, thereby improving performance on melody transcription by $20$% relative to conventional spectrogram features. Another obstacle in melody transcription is a lack of training data - we derive a new dataset containing $50$ hours of melody transcriptions from crowdsourced annotations of broad music. The combination of generative pre-training and a new dataset for this task results in $77$% stronger performance on melody transcription relative to the strongest available baseline. By pairing our new melody transcription approach with solutions for beat detection, key estimation, and chord recognition, we build Sheet Sage, a system capable of transcribing human-readable lead sheets directly from music audio. Audio examples can be found at https://chrisdonahue.com/sheetsage and code at https://github.com/chrisdonahue/sheetsage .

Artificial intelligence methods including deep neural networks (DNN) can provide rapid molecular classification of tumors from routine histology with accuracy that matches or exceeds human pathologists. Discerning how neural networks make their predictions remains a significant challenge, but explainability tools help provide insights into what models have learned when corresponding histologic features are poorly defined. Here, we present a method for improving explainability of DNN models using synthetic histology generated by a conditional generative adversarial network (cGAN). We show that cGANs generate high-quality synthetic histology images that can be leveraged for explaining DNN models trained to classify molecularly-subtyped tumors, exposing histologic features associated with molecular state. Fine-tuning synthetic histology through class and layer blending illustrates nuanced morphologic differences between tumor subtypes. Finally, we demonstrate the use of synthetic histology for augmenting pathologist-in-training education, showing that these intuitive visualizations can reinforce and improve understanding of histologic manifestations of tumor biology.

有一段漫长的历史，努力与我们周围的实体和空间探索音乐元素，例如Musique Concr \'Ete和Ambient Music。在计算机音乐和数字艺术的背景下，还设计了集中在周围物体和物理空间上的互动体验。近年来，随着设备的开发和普及，在扩展现实中设计了越来越多的作品，以创造这种音乐体验。在本文中，我们描述了MR4MR，这是一项声音安装工作，使用户可以在混合现实的背景下体验与周围空间相互作用产生的旋律（MR）。用户使用HoloLens，用户可以撞击周围环境中真实对象的虚拟对象。然后，通过遵循物体发出的声音并使用音乐生成机器学习模型进行随机变化并逐渐改变旋律的声音，用户可以感觉到其环境旋律“转世”。

人通常通过按音乐形式组织元素来表达音乐思想来创作音乐。但是，对于基于神经网络的音乐生成，由于缺乏音乐形式的标签数据，很难这样做。在本文中，我们开发了Meloform，该系统是使用专家系统和神经网络以音乐形式生成旋律的系统。具体而言，1）我们设计了一个专家系统，可以通过开发从图案到短语的音乐元素到并根据预授予的音乐形式进行重复和变化的部分来生成旋律； 2）考虑到产生的旋律缺乏音乐丰富性，我们设计了一个基于变压器的改进模型，以改善旋律而不改变其音乐形式。 Meloform享有专家系统和通过神经模型的音乐丰富性学习的精确音乐形式控制的优势。主观和客观的实验评估都表明，MeloForm以97.79％的精度生成具有精确的音乐形式控制的旋律，并且在主观评估评分方面的表现优于基线系统0.75、0.50、0.50、0.86和0.89，其结构，主题，丰富性和整体质量和整体质量无需主观评估，而没有主观评估。任何标记的音乐形式数据。此外，Meloform可以支持各种形式，例如诗歌和合唱形式，隆多形式，变异形式，奏鸣曲形式，等等。

在人工智能和音乐领域中，从歌词中产生旋律是一项有趣而又具有挑战性的任务。但是，保持输入歌词和生成旋律之间的一致性的困难限制了以前作品的发电质量。在我们的建议中，我们演示了我们提出的可解释的歌词到循环的生成系统，该系统可以与用户互动以了解生成过程并重新创建所需的歌曲。为了提高与歌词匹配的旋律生成的可靠性，相互利用以增强歌词和生成的旋律之间的一致性。利用Gumbel-Softmax来解决通过生成对抗网络（GAN）生成离散音乐属性的非差异性问题。此外，发电机的预测概率输出用于推荐音乐属性。与我们的歌词到旋律生成系统互动，用户可以收听生成的AI歌曲，并通过从推荐的音乐属性中选择来重新创建新歌。

语言模型既展示了定量的改进，又展示了新的定性功能，随着规模的增加。尽管它们具有潜在的变革性影响，但这些新能力的特征却很差。为了为未来的研究提供信息，为破坏性的新模型能力做准备，并改善社会有害的效果，至关重要的是，我们必须了解目前和近乎未来的能力和语言模型的局限性。为了应对这一挑战，我们介绍了超越模仿游戏基准（Big Bench）。 Big Bench目前由204个任务组成，由132家机构的442位作者贡献。任务主题是多样的，从语言学，儿童发展，数学，常识性推理，生物学，物理学，社会偏见，软件开发等等。 Big-Bench专注于被认为超出当前语言模型的功能的任务。我们评估了OpenAI的GPT型号，Google内部密集变压器体系结构和大型基础上的开关稀疏变压器的行为，跨越了数百万到数十亿个参数。此外，一个人类专家评估者团队执行了所有任务，以提供强大的基准。研究结果包括：模型性能和校准都随规模改善，但绝对的术语（以及与评估者的性能相比）；在模型类中的性能非常相似，尽管带有稀疏性。逐渐和预测的任务通常涉及大量知识或记忆成分，而在临界规模上表现出“突破性”行为的任务通常涉及多个步骤或组成部分或脆性指标；社交偏见通常会随着含糊不清的环境而随着规模而增加，但这可以通过提示来改善。

开放程序代表全球手术的主要形式。人工智能（AI）有可能优化手术实践并改善患者结果，但努力主要集中在微创技术上。我们的工作通过策划，从YouTube，从YouTube，Open Surgical视频的最大数据集克服了培训AI模型的现有数据限制：1997年从50个国家上传的23个外科手术的视频。使用此数据集，我们开发了一种能够实时了解外科行为，手和工具的多任务AI模型 - 程序流程和外科医生技能的构建块。我们表明我们的模型推广了各种外科类型和环境。说明这种普遍性，我们直接应用了YouTube培训的模型，分析了在学术医疗中心前瞻性收集的开放式手术，并确定了与手动效率相关的外科技能的运动学描述符。我们的开放外科（AVOS）数据集和培训模式的注释视频将可用于进一步发展外科艾。

我们提出了一种生成钢琴音乐的MIDI文件的方法。该方法使用两个网络绘制右手和左手，左手在右手上调节。这样，在和谐之前产生旋律。MIDI以不变量的方式表示，以乐谱，旋律表示，为了调节和谐，通过每个杆的内容被视为弦。最后，基于此和弦表示，随机添加了Notes，以丰富生成的音频。我们的实验表现出对本领域的培训技术的显着改进，用于培训此类数据集，并证明每个新型组件的贡献。

We propose Efficient Neural Architecture Search (ENAS), a fast and inexpensive approach for automatic model design. In ENAS, a controller discovers neural network architectures by searching for an optimal subgraph within a large computational graph. The controller is trained with policy gradient to select a subgraph that maximizes the expected reward on a validation set. Meanwhile the model corresponding to the selected subgraph is trained to minimize a canonical cross entropy loss. Sharing parameters among child models allows ENAS to deliver strong empirical performances, while using much fewer GPUhours than existing automatic model design approaches, and notably, 1000x less expensive than standard Neural Architecture Search. On the Penn Treebank dataset, ENAS discovers a novel architecture that achieves a test perplexity of 55.8, establishing a new state-of-the-art among all methods without post-training processing. On the CIFAR-10 dataset, ENAS finds a novel architecture that achieves 2.89% test error, which is on par with the 2.65% test error of NAS-Net (Zoph et al., 2018).