从单眼RGB图像中重建3D手网络，由于其在AR/VR领域的巨大潜在应用，引起了人们的注意力越来越多。大多数最先进的方法试图以匿名方式解决此任务。具体而言，即使在连续录制会话中用户没有变化的实际应用程序中实际上可用，因此忽略了该主题的身份。在本文中，我们提出了一个身份感知的手网格估计模型，该模型可以结合由受试者的内在形状参数表示的身份信息。我们通过将提出的身份感知模型与匿名对待主题的基线进行比较来证明身份信息的重要性。此外，为了处理未见测试对象的用例，我们提出了一条新型的个性化管道来校准固有的形状参数，仅使用该受试者的少数未标记的RGB图像。在两个大型公共数据集上进行的实验验证了我们提出的方法的最先进性能。

最近，视觉变压器及其变体在人类和多视图人类姿势估计中均起着越来越重要的作用。将图像补丁视为令牌，变形金刚可以对整个图像中的全局依赖项进行建模或其他视图中的图像。但是，全球关注在计算上是昂贵的。结果，很难将这些基于变压器的方法扩展到高分辨率特征和许多视图。在本文中，我们提出了代币螺旋的姿势变压器（PPT）进行2D人姿势估计，该姿势估计可以找到粗糙的人掩模，并且只能在选定的令牌内进行自我注意。此外，我们将PPT扩展到多视图人类姿势估计。我们建立在PPT的基础上，提出了一种新的跨视图融合策略，称为人类区域融合，该策略将所有人类前景像素视为相应的候选者。可可和MPII的实验结果表明，我们的PPT可以在减少计算的同时匹配以前的姿势变压器方法的准确性。此外，对人类360万和滑雪姿势的实验表明，我们的多视图PPT可以有效地从多个视图中融合线索并获得新的最新结果。

图像注册广泛用于医学图像分析中，以提供两个图像之间的空间对应关系。最近提出了利用卷积神经网络（CNN）的基于学习的方法来解决图像注册问题。基于学习的方法往往比基于传统优化的方法快得多，但是从复杂的CNN方法中获得的准确性提高是适度的。在这里，我们介绍了一个新的基于深神经的图像注册框架，名为\ textbf {mirnf}，该框架代表通过通过神经字段实现的连续函数的对应映射。 MIRNF输出的变形矢量或速度向量给定3D坐标为输入。为了确保映射是差异的，使用神经ODE求解器集成了MiRNF的速度矢量输出，以得出两个图像之间的对应关系。此外，我们提出了一个混合坐标采样器以及级联的体系结构，以实现高相似性映射性能和低距离变形场。我们对两个3D MR脑扫描数据集进行了实验，这表明我们提出的框架提供了最新的注册性能，同时保持了可比的优化时间。

差异图像注册是医学图像分析中的至关重要任务。最近基于学习的图像注册方法利用卷积神经网络（CNN）学习图像对之间的空间转换并达到快速推理速度。但是，这些方法通常需要大量的培训数据来提高其概括能力。在测试时间内，基于学习的方法可能无法提供良好的注册结果，这很可能是因为培训数据集的模型过于拟合。在本文中，我们提出了连续速度场（NEVF）的神经表示，以描述两个图像之间的变形。具体而言，该神经速度场为空间中的每个点分配了一个速度向量，该速度在对复杂变形场进行建模时具有更高的灵活性。此外，我们提出了一种简单的稀疏抽样策略，以减少差异注册的记忆消耗。提出的NEVF还可以与预先训练的基于学习的模型合并，该模型的预测变形被视为优化的初始状态。在两个大规模3D MR脑扫描数据集上进行的广泛实验表明，我们提出的方法的表现优于最先进的注册方法。

估计每个视图中的2D人类姿势通常是校准多视图3D姿势估计的第一步。但是，2D姿势探测器的性能遭受挑战性的情况，例如闭塞和斜视角。为了解决这些挑战，以前的作品从eMipolar几何中的不同视图之间导出点对点对应关系，并利用对应关系来合并预测热插拔或特征表示。除了后预测合并/校准之外，我们引入了用于多视图3D姿势估计的变压器框架，其目的地通过将来自不同视图的信息集成信息来直接改善单个2D预测器。灵感来自先前的多模态变压器，我们设计一个统一的变压器体系结构，命名为输送，从当前视图和邻近视图中保险。此外，我们提出了eMipolar字段的概念来将3D位置信息编码到变压器模型中。由Epipolar字段引导的3D位置编码提供了一种有效的方式来编码不同视图的像素之间的对应关系。人类3.6M和滑雪姿势的实验表明，与其他融合方法相比，我们的方法更有效，并且具有一致的改进。具体而言，我们在256 x 256分辨率上只有5米参数达到人类3.6米的25.8毫米MPJPE。

Consensus clustering aggregates partitions in order to find a better fit by reconciling clustering results from different sources/executions. In practice, there exist noise and outliers in clustering task, which, however, may significantly degrade the performance. To address this issue, we propose a novel algorithm -- robust consensus clustering that can find common ground truth among experts' opinions, which tends to be minimally affected by the bias caused by the outliers. In particular, we formalize the robust consensus clustering problem as a constraint optimization problem, and then derive an effective algorithm upon alternating direction method of multipliers (ADMM) with rigorous convergence guarantee. Our method outperforms the baselines on benchmarks. We apply the proposed method to the real-world advertising campaign segmentation and forecasting tasks using the proposed consensus clustering results based on the similarity computed via Kolmogorov-Smirnov Statistics. The accurate clustering result is helpful for building the advertiser profiles so as to perform the forecasting.

In computational advertising, a challenging problem is how to recommend the bid for advertisers to achieve the best return on investment (ROI) given budget constraint. This paper presents a bid recommendation scenario that discovers the concavity changes in click prediction curves. The recommended bid is derived based on the turning point from significant increase (i.e. concave downward) to slow increase (convex upward). Parametric learning based method is applied by solving the corresponding constraint optimization problem. Empirical studies on real-world advertising scenarios clearly demonstrate the performance gains for business metrics (including revenue increase, click increase and advertiser ROI increase).

In cost-per-click (CPC) or cost-per-impression (CPM) advertising campaigns, advertisers always run the risk of spending the budget without getting enough conversions. Moreover, the bidding on advertising inventory has few connections with propensity one that can reach to target cost-per-acquisition (tCPA) goals. To address this problem, this paper presents a bid optimization scenario to achieve the desired tCPA goals for advertisers. In particular, we build the optimization engine to make a decision by solving the rigorously formalized constrained optimization problem, which leverages the bid landscape model learned from rich historical auction data using non-parametric learning. The proposed model can naturally recommend the bid that meets the advertisers' expectations by making inference over advertisers' historical auction behaviors, which essentially deals with the data challenges commonly faced by bid landscape modeling: incomplete logs in auctions, and uncertainty due to the variation and fluctuations in advertising bidding behaviors. The bid optimization model outperforms the baseline methods on real-world campaigns, and has been applied into a wide range of scenarios for performance improvement and revenue liftup.

We propose a new neural network design paradigm Reversible Column Network (RevCol). The main body of RevCol is composed of multiple copies of subnetworks, named columns respectively, between which multi-level reversible connections are employed. Such architectural scheme attributes RevCol very different behavior from conventional networks: during forward propagation, features in RevCol are learned to be gradually disentangled when passing through each column, whose total information is maintained rather than compressed or discarded as other network does. Our experiments suggest that CNN-style RevCol models can achieve very competitive performances on multiple computer vision tasks such as image classification, object detection and semantic segmentation, especially with large parameter budget and large dataset. For example, after ImageNet-22K pre-training, RevCol-XL obtains 88.2% ImageNet-1K accuracy. Given more pre-training data, our largest model RevCol-H reaches 90.0% on ImageNet-1K, 63.8% APbox on COCO detection minival set, 61.0% mIoU on ADE20k segmentation. To our knowledge, it is the best COCO detection and ADE20k segmentation result among pure (static) CNN models. Moreover, as a general macro architecture fashion, RevCol can also be introduced into transformers or other neural networks, which is demonstrated to improve the performances in both computer vision and NLP tasks. We release code and models at https://github.com/megvii-research/RevCol

We address the theoretical and practical problems related to the trajectory generation and tracking control of tail-sitter UAVs. Theoretically, we focus on the differential flatness property with full exploitation of actual UAV aerodynamic models, which lays a foundation for generating dynamically feasible trajectory and achieving high-performance tracking control. We have found that a tail-sitter is differentially flat with accurate aerodynamic models within the entire flight envelope, by specifying coordinate flight condition and choosing the vehicle position as the flat output. This fundamental property allows us to fully exploit the high-fidelity aerodynamic models in the trajectory planning and tracking control to achieve accurate tail-sitter flights. Particularly, an optimization-based trajectory planner for tail-sitters is proposed to design high-quality, smooth trajectories with consideration of kinodynamic constraints, singularity-free constraints and actuator saturation. The planned trajectory of flat output is transformed to state trajectory in real-time with consideration of wind in environments. To track the state trajectory, a global, singularity-free, and minimally-parameterized on-manifold MPC is developed, which fully leverages the accurate aerodynamic model to achieve high-accuracy trajectory tracking within the whole flight envelope. The effectiveness of the proposed framework is demonstrated through extensive real-world experiments in both indoor and outdoor field tests, including agile SE(3) flight through consecutive narrow windows requiring specific attitude and with speed up to 10m/s, typical tail-sitter maneuvers (transition, level flight and loiter) with speed up to 20m/s, and extremely aggressive aerobatic maneuvers (Wingover, Loop, Vertical Eight and Cuban Eight) with acceleration up to 2.5g.