Adequate strategizing of agents behaviors is essential to solving cooperative MARL problems. One intuitively beneficial yet uncommon method in this domain is predicting agents future behaviors and planning accordingly. Leveraging this point, we propose a two-level hierarchical architecture that combines a novel information-theoretic objective with a trajectory prediction model to learn a strategy. To this end, we introduce a latent policy that learns two types of latent strategies: individual $z_A$, and relational $z_R$ using a modified Graph Attention Network module to extract interaction features. We encourage each agent to behave according to the strategy by conditioning its local $Q$ functions on $z_A$, and we further equip agents with a shared $Q$ function that conditions on $z_R$. Additionally, we introduce two regularizers to allow predicted trajectories to be accurate and rewarding. Empirical results on Google Research Football (GRF) and StarCraft (SC) II micromanagement tasks show that our method establishes a new state of the art being, to the best of our knowledge, the first MARL algorithm to solve all super hard SC II scenarios as well as the GRF full game with a win rate higher than $95\%$, thus outperforming all existing methods. Videos and brief overview of the methods and results are available at: https://sites.google.com/view/hier-strats-marl/home.
translated by 谷歌翻译
In intensively managed forests in Europe, where forests are divided into stands of small size and may show heterogeneity within stands, a high spatial resolution (10 - 20 meters) is arguably needed to capture the differences in canopy height. In this work, we developed a deep learning model based on multi-stream remote sensing measurements to create a high-resolution canopy height map over the "Landes de Gascogne" forest in France, a large maritime pine plantation of 13,000 km$^2$ with flat terrain and intensive management. This area is characterized by even-aged and mono-specific stands, of a typical length of a few hundred meters, harvested every 35 to 50 years. Our deep learning U-Net model uses multi-band images from Sentinel-1 and Sentinel-2 with composite time averages as input to predict tree height derived from GEDI waveforms. The evaluation is performed with external validation data from forest inventory plots and a stereo 3D reconstruction model based on Skysat imagery available at specific locations. We trained seven different U-net models based on a combination of Sentinel-1 and Sentinel-2 bands to evaluate the importance of each instrument in the dominant height retrieval. The model outputs allow us to generate a 10 m resolution canopy height map of the whole "Landes de Gascogne" forest area for 2020 with a mean absolute error of 2.02 m on the Test dataset. The best predictions were obtained using all available satellite layers from Sentinel-1 and Sentinel-2 but using only one satellite source also provided good predictions. For all validation datasets in coniferous forests, our model showed better metrics than previous canopy height models available in the same region.
translated by 谷歌翻译
Unsupervised object discovery aims to localize objects in images, while removing the dependence on annotations required by most deep learning-based methods. To address this problem, we propose a fully unsupervised, bottom-up approach, for multiple objects discovery. The proposed approach is a two-stage framework. First, instances of object parts are segmented by using the intra-image similarity between self-supervised local features. The second step merges and filters the object parts to form complete object instances. The latter is performed by two CNN models that capture semantic information on objects from the entire dataset. We demonstrate that the pseudo-labels generated by our method provide a better precision-recall trade-off than existing single and multiple objects discovery methods. In particular, we provide state-of-the-art results for both unsupervised class-agnostic object detection and unsupervised image segmentation.
translated by 谷歌翻译
Survival analysis is the branch of statistics that studies the relation between the characteristics of living entities and their respective survival times, taking into account the partial information held by censored cases. A good analysis can, for example, determine whether one medical treatment for a group of patients is better than another. With the rise of machine learning, survival analysis can be modeled as learning a function that maps studied patients to their survival times. To succeed with that, there are three crucial issues to be tackled. First, some patient data is censored: we do not know the true survival times for all patients. Second, data is scarce, which led past research to treat different illness types as domains in a multi-task setup. Third, there is the need for adaptation to new or extremely rare illness types, where little or no labels are available. In contrast to previous multi-task setups, we want to investigate how to efficiently adapt to a new survival target domain from multiple survival source domains. For this, we introduce a new survival metric and the corresponding discrepancy measure between survival distributions. These allow us to define domain adaptation for survival analysis while incorporating censored data, which would otherwise have to be dropped. Our experiments on two cancer data sets reveal a superb performance on target domains, a better treatment recommendation, and a weight matrix with a plausible explanation.
translated by 谷歌翻译
Large language models (LLMs) have been shown to be able to perform new tasks based on a few demonstrations or natural language instructions. While these capabilities have led to widespread adoption, most LLMs are developed by resource-rich organizations and are frequently kept from the public. As a step towards democratizing this powerful technology, we present BLOOM, a 176B-parameter open-access language model designed and built thanks to a collaboration of hundreds of researchers. BLOOM is a decoder-only Transformer language model that was trained on the ROOTS corpus, a dataset comprising hundreds of sources in 46 natural and 13 programming languages (59 in total). We find that BLOOM achieves competitive performance on a wide variety of benchmarks, with stronger results after undergoing multitask prompted finetuning. To facilitate future research and applications using LLMs, we publicly release our models and code under the Responsible AI License.
translated by 谷歌翻译
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.
translated by 谷歌翻译
大多数人工智能(AI)研究都集中在高收入国家,其中成像数据,IT基础设施和临床专业知识丰富。但是,在需要医学成像的有限资源环境中取得了较慢的进步。例如,在撒哈拉以南非洲,由于获得产前筛查的机会有限,围产期死亡率的率很高。在这些国家,可以实施AI模型,以帮助临床医生获得胎儿超声平面以诊断胎儿异常。到目前为止,已经提出了深度学习模型来识别标准的胎儿平面,但是没有证据表明它们能够概括获得高端超声设备和数据的中心。这项工作研究了不同的策略,以减少在高资源临床中心训练并转移到新的低资源中心的胎儿平面分类模型的域转移效果。为此,首先在丹麦的一个新中心对1,008例患者的新中心进行评估,接受了1,008名患者的新中心,后来对五个非洲中心(埃及,阿尔及利亚,乌干达,加纳和马拉维进行了相同的表现),首先在丹麦的一个新中心进行评估。 )每个患者有25名。结果表明,转移学习方法可以是将小型非洲样本与发达国家现有的大规模数据库相结合的解决方案。特别是,该模型可以通过将召回率提高到0.92 \ pm 0.04 $,同时又可以维持高精度。该框架显示了在临床中心构建可概括的新AI模型的希望,该模型在具有挑战性和异质条件下获得的数据有限,并呼吁进行进一步的研究,以开发用于资源较少的国家 /地区的AI可用性的新解决方案。
translated by 谷歌翻译
优化组合结构是许多现实世界中的核心,例如生命科学中遇到的问题。例如,抗体设计中涉及的关键步骤之一是在蛋白质序列中找到氨基酸的排列,以改善其与病原体的结合。由于极大的搜索空间和非线性目标,很难对抗体进行组合优化。即使对于适度的抗体设计问题,蛋白质的序列长度为11,我们也面临着超过2.05 x 10^14结构的搜索。应用传统的增强学习算法,例如Q-学习算法来组合优化,导致性能差。我们提出了结构化Q学习(SQL),这是Q学习的扩展,该Q学习结合了结构性先验,以进行组合优化。使用分子对接模拟器,我们证明了SQL可以找到高结合能序列,并在八个具有挑战性的抗体设计任务上对基准的表现良好,包括设计SARS-COV的抗体。
translated by 谷歌翻译
牙齿分割是牙科修复体中的一个重要主题,这对于牙冠的产生,诊断和治疗计划至关重要。在牙科字段中,输入数据的可变性很高,没有公开可用的3D牙科拱门数据集。尽管最近对3D数据的深度学习体系结构提供的领域有所改善,但仍然存在一些问题,例如正确识别拱门中缺失的牙齿。我们建议将光谱聚类用作自我探测信号,以将3D拱门分割的联合训练神经网络进行分割。我们的方法是通过观察到的,即K-均值聚类提供了捕获与人类感知相关的边缘线的线索。主要思想是通过将未标记的3D拱门分解为仅依靠几何信息的细分市场来自动生成训练数据。然后,使用关节损失对网络进行训练,该联合损失结合了注释输入的监督损失和无标签输入的自制损失。我们收集的数据有多种拱门,包括牙齿缺失的拱门。我们的实验结果表明,在使用半监督学习时,对完全监督的最先进的meshsegnet进行了改善。最后,我们贡献代码和数据集。
translated by 谷歌翻译
在视频中,人类的行为是三维(3D)信号。这些视频研究了人类行为的时空知识。使用3D卷积神经网络(CNN)研究了有希望的能力。 3D CNN尚未在静止照片中为其建立良好的二维(2D)等效物获得高输出。董事会3D卷积记忆和时空融合面部训练难以防止3D CNN完成非凡的评估。在本文中,我们实施了混合深度学习体系结构,该体系结构结合了Stip和3D CNN功能,以有效地增强3D视频的性能。实施后,在每个时空融合圈中进行训练的较详细和更深的图表。训练模型在处理模型的复杂评估后进一步增强了结果。视频分类模型在此实现模型中使用。引入了使用深度学习的多媒体数据分类的智能3D网络协议,以进一步了解人类努力中的时空关联。在实施结果时,著名的数据集(即UCF101)评估了提出的混合技术的性能。结果击败了提出的混合技术,该混合动力技术基本上超过了最初的3D CNN。将结果与文献的最新框架进行比较,以识别UCF101的行动识别,准确度为95%。
translated by 谷歌翻译