Camera and lidar are important sensor modalities for robotics in general and self-driving cars in particular. The sensors provide complementary information offering an opportunity for tight sensor-fusion. Surprisingly, lidar-only methods outperform fusion methods on the main benchmark datasets, suggesting a gap in the literature. In this work, we propose PointPainting: a sequential fusion method to fill this gap. PointPainting works by projecting lidar points into the output of an image-only semantic segmentation network and appending the class scores to each point. The appended (painted) point cloud can then be fed to any lidaronly method. Experiments show large improvements on three different state-of-the art methods, Point-RCNN, Vox-elNet and PointPillars on the KITTI and nuScenes datasets. The painted version of PointRCNN represents a new state of the art on the KITTI leaderboard for the bird's-eye view detection task. In ablation, we study how the effects of Painting depends on the quality and format of the semantic segmentation output, and demonstrate how latency can be minimized through pipelining.

Robust detection and tracking of objects is crucial for the deployment of autonomous vehicle technology. Image based benchmark datasets have driven development in computer vision tasks such as object detection, tracking and segmentation of agents in the environment. Most autonomous vehicles, however, carry a combination of cameras and range sensors such as lidar and radar. As machine learning based methods for detection and tracking become more prevalent, there is a need to train and evaluate such methods on datasets containing range sensor data along with images. In this work we present nuTonomy scenes (nuScenes), the first dataset to carry the full autonomous vehicle sensor suite: 6 cameras, 5 radars and 1 lidar, all with full 360 degree field of view. nuScenes comprises 1000 scenes, each 20s long and fully annotated with 3D bounding boxes for 23 classes and 8 attributes. It has 7x as many annotations and 100x as many images as the pioneering KITTI dataset. We define novel 3D detection and tracking metrics. We also provide careful dataset analysis as well as baselines for lidar and image based detection and tracking. Data, development kit and more information are available online 1 .

Object detection in point clouds is an important aspect of many robotics applications such as autonomous driving. In this paper we consider the problem of encoding a point cloud into a format appropriate for a downstream detection pipeline. Recent literature suggests two types of encoders; fixed encoders tend to be fast but sacrifice accuracy, while encoders that are learned from data are more accurate, but slower. In this work we propose PointPillars, a novel encoder which utilizes PointNets to learn a representation of point clouds organized in vertical columns (pillars). While the encoded features can be used with any standard 2D convolutional detection architecture, we further propose a lean downstream network. Extensive experimentation shows that PointPillars outperforms previous encoders with respect to both speed and accuracy by a large margin. Despite only using lidar, our full detection pipeline significantly outperforms the state of the art, even among fusion methods, with respect to both the 3D and bird's eye view KITTI benchmarks. This detection performance is achieved while running at 62 Hz: a 2 -4 fold runtime improvement. A faster version of our method matches the state of the art at 105 Hz. These benchmarks suggest that PointPillars is an appropriate encoding for object detection in point clouds.

In recent years, there has been a surge of interest in research on automatic mental health detection (MHD) from social media data leveraging advances in natural language processing and machine learning techniques. While significant progress has been achieved in this interdisciplinary research area, the vast majority of work has treated MHD as a binary classification task. The multiclass classification setup is, however, essential if we are to uncover the subtle differences among the statistical patterns of language use associated with particular mental health conditions. Here, we report on experiments aimed at predicting six conditions (anxiety, attention deficit hyperactivity disorder, bipolar disorder, post-traumatic stress disorder, depression, and psychological stress) from Reddit social media posts. We explore and compare the performance of hybrid and ensemble models leveraging transformer-based architectures (BERT and RoBERTa) and BiLSTM neural networks trained on within-text distributions of a diverse set of linguistic features. This set encompasses measures of syntactic complexity, lexical sophistication and diversity, readability, and register-specific ngram frequencies, as well as sentiment and emotion lexicons. In addition, we conduct feature ablation experiments to investigate which types of features are most indicative of particular mental health conditions.

In recent years, there has been increased interest in building predictive models that harness natural language processing and machine learning techniques to detect emotions from various text sources, including social media posts, micro-blogs or news articles. Yet, deployment of such models in real-world sentiment and emotion applications faces challenges, in particular poor out-of-domain generalizability. This is likely due to domain-specific differences (e.g., topics, communicative goals, and annotation schemes) that make transfer between different models of emotion recognition difficult. In this work we propose approaches for text-based emotion detection that leverage transformer models (BERT and RoBERTa) in combination with Bidirectional Long Short-Term Memory (BiLSTM) networks trained on a comprehensive set of psycholinguistic features. First, we evaluate the performance of our models within-domain on two benchmark datasets: GoEmotion and ISEAR. Second, we conduct transfer learning experiments on six datasets from the Unified Emotion Dataset to evaluate their out-of-domain robustness. We find that the proposed hybrid models improve the ability to generalize to out-of-distribution data compared to a standard transformer-based approach. Moreover, we observe that these models perform competitively on in-domain data.

我们提出了一个新的灵敏度分析模型，该模型结合了Copulas和在未观察到的混杂状态下的因果推断的标准化。我们将新模型称为$ \ rho $ -gnf（$ \ rho $ - graphical正常化流），其中$ \ rho {\ in} [ - 1，+1] $是一个有界灵敏度参数，表示后门非 - 由于未观察到的混杂而引起的因果关系，使用研究最丰富且广泛流行的高斯副群建模。具体而言，$ \ rho $ -gnf使我们能够估计和分析前门因果效应或平均因果效应（ACE）作为$ \ rho $的函数。我们将其称为$ \ rho_ {curve} $。 $ \ rho_ {curve} $使我们能够指定无王牌所需的混杂力量。我们将其称为$ \ rho_ {value} $。此外，$ \ rho_ {curve} $还使我们能够为$ \ rho $ values的间隔提供ACE的界限。我们说明了$ \ rho $ -gnf的好处，并通过对我们的经验王牌界限的实验比其他流行的王牌范围更狭窄。

关于自适应梯度方法等自适应梯度方法等训练动力的知之甚少。在本文中，我们阐明了这些算法在全批处理和足够大的批处理设置中的行为。具体而言，我们从经验上证明，在全批训练中，预处理的Hessian的最大特征值通常在某个数值下平衡 - 梯度下降算法的稳定性阈值。对于带有步长$ \ eta $和$ \ beta_1 = 0.9 $的Adam，此稳定性阈值为$ 38/\ eta $。在Minibatch培训期间发生了类似的影响，尤其是随着批处理大小的增长。然而，即使自适应方法在``稳定性的自适应边缘''（AEOS）上训练，但它们在该制度中的行为与EOS的非自适应方法的行为有很大不同。 EOS处的非自适应算法被阻止进入损失景观的高曲率区域，而AEOS的自适应梯度方法可以继续前进到高外观区域，同时适应预先调节器以补偿。我们的发现可以成为社区对深度学习中适应性梯度方法的未来理解的基础。

6-DOF的视觉定位系统利用植根于3D几何形状的原则方法来对图像进行准确的摄像头姿势估计图。当前的技术使用层次管道并学到了2D功能提取器来提高可扩展性并提高性能。但是，尽管典型召回@0.25m类型的指标获得了，但由于其“最差”性能领域，这些系统仍然对实际应用（如自动驾驶汽车）的实用性有限 - 在某种程度上提供不足的召回率的位置。在这里，我们研究了使用“位置特定配置”的实用性，其中将地图分割为多个位置，每个位置都有自己的配置，用于调节姿势估计步骤，在这种情况下，在多摄像机系统中选择摄像机。在福特AV基准数据集上，我们证明了与使用现成管道相比，我们证明了最大的最差案例定位性能 - 最小化数据集的百分比，该数据集的百分比降低了一定的误差耐受性，并提高了整体定位性能。我们提出的方法尤其适用于自动驾驶汽车部署的众群体模型，在该模型中，AV机队定期穿越已知的路线。

我们呈现NESF，一种用于单独从构成的RGB图像中生成3D语义场的方法。代替经典的3D表示，我们的方法在最近的基础上建立了隐式神经场景表示的工作，其中3D结构被点亮功能捕获。我们利用这种方法来恢复3D密度领域，我们然后在其中培训由构成的2D语义地图监督的3D语义分段模型。尽管仅在2D信号上培训，我们的方法能够从新颖的相机姿势生成3D一致的语义地图，并且可以在任意3D点查询。值得注意的是，NESF与产生密度场的任何方法兼容，并且随着密度场的质量改善，其精度可提高。我们的实证分析在复杂的实际呈现的合成场景中向竞争性2D和3D语义分割基线表现出可比的质量。我们的方法是第一个提供真正密集的3D场景分段，需要仅需要2D监督培训，并且不需要任何关于新颖场景的推论的语义输入。我们鼓励读者访问项目网站。

计算机愿景中的经典问题是推断从几个可用于以交互式速率渲染新颖视图的图像的3D场景表示。以前的工作侧重于重建预定定义的3D表示，例如，纹理网格或隐式表示，例如隐式表示。辐射字段，并且通常需要输入图像，具有精确的相机姿势和每个新颖场景的长处理时间。在这项工作中，我们提出了场景表示变换器（SRT），一种方法，该方法处理新的区域的构成或未铺设的RGB图像，Infers Infers“设置 - 潜在场景表示”，并合成新颖的视图，全部在一个前馈中经过。为了计算场景表示，我们提出了视觉变压器的概括到图像组，实现全局信息集成，从而实现3D推理。一个有效的解码器变压器通过参加场景表示来参加光场以呈现新颖的视图。通过最大限度地减少新型视图重建错误，学习是通过最终到底的。我们表明，此方法在PSNR和Synthetic DataSets上的速度方面优于最近的基线，包括为纸张创建的新数据集。此外，我们展示了使用街景图像支持现实世界户外环境的交互式可视化和语义分割。