无似然方法是对可以模拟的隐式模型执行推断的必不可少的工具，但相应的可能性是棘手的。但是，常见的无可能方法不能很好地扩展到大量模型参数。一种有前途的无可能推理的有前途的方法涉及通过仅根据据信为低维成分提供信息的摘要统计数据来估计低维边缘后期，然后在某种程度上结合了低维近似值。在本文中，我们证明，对于看似直观的汇总统计选择，这种低维近似值在实践中可能是差的。我们描述了一个理想化的低维汇总统计量，原则上适用于边际估计。但是，在实践中很难直接近似理想的选择。因此，我们提出了一种替代的边际估计方法，该方法更容易实施和自动化。考虑到初始选择的低维摘要统计量可能仅对边缘后验位置有用，新方法通过使用所有摘要统计数据来确保全局可识别性来提高性能，从而提高性能使用低维摘要统计量进行精确的低维近似。我们表明，该方法的后部可以分别基于低维和完整的摘要统计数据将其表示为后验分布的对数库。在几个示例中说明了我们方法的良好性能。

Deep learning classifiers provide the most accurate means of automatically diagnosing diabetic retinopathy (DR) based on optical coherence tomography (OCT) and its angiography (OCTA). The power of these models is attributable in part to the inclusion of hidden layers that provide the complexity required to achieve a desired task. However, hidden layers also render algorithm outputs difficult to interpret. Here we introduce a novel biomarker activation map (BAM) framework based on generative adversarial learning that allows clinicians to verify and understand classifiers decision-making. A data set including 456 macular scans were graded as non-referable or referable DR based on current clinical standards. A DR classifier that was used to evaluate our BAM was first trained based on this data set. The BAM generation framework was designed by combing two U-shaped generators to provide meaningful interpretability to this classifier. The main generator was trained to take referable scans as input and produce an output that would be classified by the classifier as non-referable. The BAM is then constructed as the difference image between the output and input of the main generator. To ensure that the BAM only highlights classifier-utilized biomarkers an assistant generator was trained to do the opposite, producing scans that would be classified as referable by the classifier from non-referable scans. The generated BAMs highlighted known pathologic features including nonperfusion area and retinal fluid. A fully interpretable classifier based on these highlights could help clinicians better utilize and verify automated DR diagnosis.

With the progress of sensor technology in wearables, the collection and analysis of PPG signals are gaining more interest. Using Machine Learning, the cardiac rhythm corresponding to PPG signals can be used to predict different tasks such as activity recognition, sleep stage detection, or more general health status. However, supervised learning is often limited by the amount of available labeled data, which is typically expensive to obtain. To address this problem, we propose a Self-Supervised Learning (SSL) method with a pretext task of signal reconstruction to learn an informative generalized PPG representation. The performance of the proposed SSL framework is compared with two fully supervised baselines. The results show that in a very limited label data setting (10 samples per class or less), using SSL is beneficial, and a simple classifier trained on SSL-learned representations outperforms fully supervised deep neural networks. However, the results reveal that the SSL-learned representations are too focused on encoding the subjects. Unfortunately, there is high inter-subject variability in the SSL-learned representations, which makes working with this data more challenging when labeled data is scarce. The high inter-subject variability suggests that there is still room for improvements in learning representations. In general, the results suggest that SSL may pave the way for the broader use of machine learning models on PPG data in label-scarce regimes.

Many current approaches to machine learning in particle physics use generic architectures that require large numbers of parameters and disregard underlying physics principles, limiting their applicability as scientific modeling tools. In this work, we present a machine learning architecture that uses a set of inputs maximally reduced with respect to the full 6-dimensional Lorentz symmetry, and is fully permutation-equivariant throughout. We study the application of this network architecture to the standard task of top quark tagging and show that the resulting network outperforms all existing competitors despite much lower model complexity. In addition, we present a Lorentz-covariant variant of the same network applied to a 4-momentum regression task.

To analyze this characteristic of vulnerability, we developed an automated deep learning method for detecting microvessels in intravascular optical coherence tomography (IVOCT) images. A total of 8,403 IVOCT image frames from 85 lesions and 37 normal segments were analyzed. Manual annotation was done using a dedicated software (OCTOPUS) previously developed by our group. Data augmentation in the polar (r,{\theta}) domain was applied to raw IVOCT images to ensure that microvessels appear at all possible angles. Pre-processing methods included guidewire/shadow detection, lumen segmentation, pixel shifting, and noise reduction. DeepLab v3+ was used to segment microvessel candidates. A bounding box on each candidate was classified as either microvessel or non-microvessel using a shallow convolutional neural network. For better classification, we used data augmentation (i.e., angle rotation) on bounding boxes with a microvessel during network training. Data augmentation and pre-processing steps improved microvessel segmentation performance significantly, yielding a method with Dice of 0.71+/-0.10 and pixel-wise sensitivity/specificity of 87.7+/-6.6%/99.8+/-0.1%. The network for classifying microvessels from candidates performed exceptionally well, with sensitivity of 99.5+/-0.3%, specificity of 98.8+/-1.0%, and accuracy of 99.1+/-0.5%. The classification step eliminated the majority of residual false positives, and the Dice coefficient increased from 0.71 to 0.73. In addition, our method produced 698 image frames with microvessels present, compared to 730 from manual analysis, representing a 4.4% difference. When compared to the manual method, the automated method improved microvessel continuity, implying improved segmentation performance. The method will be useful for research purposes as well as potential future treatment planning.

在许多情况下，更简单的模型比更复杂的模型更可取，并且该模型复杂性的控制是机器学习中许多方法的目标，例如正则化，高参数调整和体系结构设计。在深度学习中，很难理解复杂性控制的潜在机制，因为许多传统措施并不适合深度神经网络。在这里，我们开发了几何复杂性的概念，该概念是使用离散的dirichlet能量计算的模型函数变异性的量度。使用理论论据和经验结果的结合，我们表明，许多常见的训练启发式方法，例如参数规范正规化，光谱规范正则化，平稳性正则化，隐式梯度正则化，噪声正则化和参数初始化的选择，都可以控制几何学复杂性，并提供一个统一的框架，以表征深度学习模型的行为。

机器学习潜力是分子模拟的重要工具，但是由于缺乏高质量数据集来训练它们的发展，它们的开发阻碍了它们。我们描述了Spice数据集，这是一种新的量子化学数据集，用于训练与模拟与蛋白质相互作用的药物样的小分子相关的潜在。它包含超过110万个小分子，二聚体，二肽和溶剂化氨基酸的构象。它包括15个元素，带电和未充电的分子以及广泛的共价和非共价相互作用。它提供了在{\ omega} b97m-d3（bj）/def2-tzVPPD理论水平以及其他有用的数量（例如多极矩和键阶）上计算出的力和能量。我们在其上训练一组机器学习潜力，并证明它们可以在化学空间的广泛区域中实现化学精度。它可以作为创建可转移的，准备使用潜在功能用于分子模拟的宝贵资源。

光学计算是一种新兴技术，用于下一代高效人工智能（AI），其速度和效率超高。电磁场模拟对于光子设备和电路的设计，优化和验证至关重要。但是，昂贵的数值模拟显着阻碍了光子电路设计循环中的可扩展性和转环。最近，已经提出了物理信息的神经网络来预测具有预定义参数的部分微分方程（PDE）的单个实例的光场解。它们复杂的PDE公式和缺乏有效的参数化机制限制了其在实际模拟方案中的灵活性和概括。在这项工作中，首次提出了一个被称为Neurolight的物理敏捷神经操作员框架，以学习一个频率域的麦克斯韦PDE家族，以进行超快速的参数光子设备模拟。我们通过几种新技术来平衡神经照明的效率和概括。具体而言，我们将不同的设备离散到统一域中，代表具有紧凑型波的参数PDE，并通过掩盖的源建模编码入射光。我们使用参数效率高的跨形神经块设计模型，并采用基于叠加的增强来进行数据效率学习。通过这些协同方法，神经亮像可以概括为大量的看不见的模拟设置，比数值求解器显示了2个磁性的模拟速度，并且比先前的神经网络模型优于降低54％的预测误差，而降低了约44％的参数。 。我们的代码可在https://github.com/jeremiemelo/neurolight上找到。

大量的研究与逼真的传感器数据的产生有关。激光点云是由复杂的模拟或学习的生成模型生成的。通常利用生成的数据来启用或改善下游感知算法。这些程序来自两个主要问题：首先，如何评估生成数据的现实主义？其次，更现实的数据还会导致更好的感知表现吗？本文解决了问题，并提出了一个新颖的指标，以量化LiDar Point Cloud的现实主义。通过训练代理分类任务，可以从现实世界和合成点云中学到相关功能。在一系列实验中，我们证明了我们的指标的应用来确定生成的LiDAR数据的现实主义，并将我们的度量的现实主义估计与分割模型的性能进行比较。我们确认我们的指标为下游细分性能提供了指示。

给定一个较小的培训数据集和学习算法，要达到目标验证或测试性能需要多少数据？这个问题至关重要，在诸如自动驾驶或医学成像之类的应用中，收集数据昂贵且耗时。高估或低估数据需求会带来大量费用，而预算可以避免。关于神经缩放定律的先前工作表明，幂律函数可以符合验证性能曲线并将其推断为较大的数据集大小。我们发现，这并不能立即转化为估计所需数据集大小以满足目标性能的更困难的下游任务。在这项工作中，我们考虑了一系列的计算机视觉任务，并系统地研究了一个概括功能功能的功能家族，以便更好地估算数据需求。最后，我们表明，结合调整的校正因子并在多个回合中收集会显着提高数据估计器的性能。使用我们的准则，从业人员可以准确估算机器学习系统的数据要求，以节省开发时间和数据采集成本。