可靠地预测围绕自动赛车的参赛者车辆的动议对于有效和表现计划至关重要。尽管高度表现力，但深度神经网络是黑盒模型，使其在安全至关重要的应用（例如自动驾驶）中具有挑战性。在本文中，我们介绍了一种结构化的方式，以预测具有深神网络的对立赛车的运动。最终可能的输出轨迹集受到限制。因此，可以给出有关预测的质量保证。我们通过将模型与基于LSTM的编码器架构一起评估模型来报告该模型的性能，这些架构是从高保真硬件中获取的数据中获得的。拟议的方法的表现优于预测准确性的基线，但仍能履行质量保证。因此，该模型的强大现实应用已被证明。介绍的模型被部署在慕尼黑技术大学的Indy Automous Challenge 2021中。本研究中使用的代码可作为开放源软件提供，网址为www.github.com/tumftm/mixnet。

Humans form mental images of 3D scenes to support counterfactual imagination, planning, and motor control. Our abilities to predict the appearance and affordance of the scene from previously unobserved viewpoints aid us in performing manipulation tasks (e.g., 6-DoF kitting) with a level of ease that is currently out of reach for existing robot learning frameworks. In this work, we aim to build artificial systems that can analogously plan actions on top of imagined images. To this end, we introduce Mental Imagery for Robotic Affordances (MIRA), an action reasoning framework that optimizes actions with novel-view synthesis and affordance prediction in the loop. Given a set of 2D RGB images, MIRA builds a consistent 3D scene representation, through which we synthesize novel orthographic views amenable to pixel-wise affordances prediction for action optimization. We illustrate how this optimization process enables us to generalize to unseen out-of-plane rotations for 6-DoF robotic manipulation tasks given a limited number of demonstrations, paving the way toward machines that autonomously learn to understand the world around them for planning actions.

Computational fluid dynamics (CFD) is a valuable asset for patient-specific cardiovascular-disease diagnosis and prognosis, but its high computational demands hamper its adoption in practice. Machine-learning methods that estimate blood flow in individual patients could accelerate or replace CFD simulation to overcome these limitations. In this work, we consider the estimation of vector-valued quantities on the wall of three-dimensional geometric artery models. We employ group-equivariant graph convolution in an end-to-end SE(3)-equivariant neural network that operates directly on triangular surface meshes and makes efficient use of training data. We run experiments on a large dataset of synthetic coronary arteries and find that our method estimates directional wall shear stress (WSS) with an approximation error of 7.6% and normalised mean absolute error (NMAE) of 0.4% while up to two orders of magnitude faster than CFD. Furthermore, we show that our method is powerful enough to accurately predict transient, vector-valued WSS over the cardiac cycle while conditioned on a range of different inflow boundary conditions. These results demonstrate the potential of our proposed method as a plugin replacement for CFD in the personalised prediction of hemodynamic vector and scalar fields.

Cross-lingual transfer learning without labeled target language data or parallel text has been surprisingly effective in zero-shot cross-lingual classification, question answering, unsupervised machine translation, etc. However, some recent publications have claimed that domain mismatch prevents cross-lingual transfer, and their results show that unsupervised bilingual lexicon induction (UBLI) and unsupervised neural machine translation (UNMT) do not work well when the underlying monolingual corpora come from different domains (e.g., French text from Wikipedia but English text from UN proceedings). In this work, we show that a simple initialization regimen can overcome much of the effect of domain mismatch in cross-lingual transfer. We pre-train word and contextual embeddings on the concatenated domain-mismatched corpora, and use these as initializations for three tasks: MUSE UBLI, UN Parallel UNMT, and the SemEval 2017 cross-lingual word similarity task. In all cases, our results challenge the conclusions of prior work by showing that proper initialization can recover a large portion of the losses incurred by domain mismatch.

Learning image representations using synthetic data allows training neural networks without some of the concerns associated with real images, such as privacy and bias. Existing work focuses on a handful of curated generative processes which require expert knowledge to design, making it hard to scale up. To overcome this, we propose training with a large dataset of twenty-one thousand programs, each one generating a diverse set of synthetic images. These programs are short code snippets, which are easy to modify and fast to execute using OpenGL. The proposed dataset can be used for both supervised and unsupervised representation learning, and reduces the gap between pre-training with real and procedurally generated images by 38%.

Asymmetrical distance structures (quasimetrics) are ubiquitous in our lives and are gaining more attention in machine learning applications. Imposing such quasimetric structures in model representations has been shown to improve many tasks, including reinforcement learning (RL) and causal relation learning. In this work, we present four desirable properties in such quasimetric models, and show how prior works fail at them. We propose Interval Quasimetric Embedding (IQE), which is designed to satisfy all four criteria. On three quasimetric learning experiments, IQEs show strong approximation and generalization abilities, leading to better performance and improved efficiency over prior methods. Project Page: https://www.tongzhouwang.info/interval_quasimetric_embedding Quasimetric Learning Code Package: https://www.github.com/quasimetric-learning/torch-quasimetric

Federated Learning (FL) is a scheme for collaboratively training Deep Neural Networks (DNNs) with multiple data sources from different clients. Instead of sharing the data, each client trains the model locally, resulting in improved privacy. However, recently so-called targeted poisoning attacks have been proposed that allow individual clients to inject a backdoor into the trained model. Existing defenses against these backdoor attacks either rely on techniques like Differential Privacy to mitigate the backdoor, or analyze the weights of the individual models and apply outlier detection methods that restricts these defenses to certain data distributions. However, adding noise to the models' parameters or excluding benign outliers might also reduce the accuracy of the collaboratively trained model. Additionally, allowing the server to inspect the clients' models creates a privacy risk due to existing knowledge extraction methods. We propose CrowdGuard, a model filtering defense, that mitigates backdoor attacks by leveraging the clients' data to analyze the individual models before the aggregation. To prevent data leaks, the server sends the individual models to secure enclaves, running in client-located Trusted Execution Environments. To effectively distinguish benign and poisoned models, even if the data of different clients are not independently and identically distributed (non-IID), we introduce a novel metric called HLBIM to analyze the outputs of the DNN's hidden layers. We show that the applied significance-based detection algorithm combined can effectively detect poisoned models, even in non-IID scenarios. We show in our extensive evaluation that CrowdGuard can effectively mitigate targeted poisoning attacks and achieve in various scenarios a True-Positive-Rate of 100% and a True-Negative-Rate of 100%.

我们介绍了一种新的图像取证方法：将物理折射物（我们称为图腾）放入场景中，以保护该场景拍摄的任何照片。图腾弯曲并重定向光线，因此在单个图像中提供了多个（尽管扭曲）的多个（尽管扭曲）。防守者可以使用这些扭曲的图腾像素来检测是否已操纵图像。我们的方法通过估计场景中的位置并使用其已知的几何和材料特性来估算其位置，从而使光线通过图腾的光线不十障。为了验证图腾保护的图像，我们从图腾视点重建的场景与场景的外观从相机的角度来检测到不一致之处。这样的方法使对抗性操纵任务更加困难，因为对手必须以几何一致的方式对图腾和图像像素进行修改，而又不知道图腾的物理特性。与先前的基于学习的方法不同，我们的方法不需要在特定操作的数据集上进行培训，而是使用场景和相机的物理属性来解决取证问题。

针对变压器的神经体系结构搜索（NAS）已用于创建针对某些延迟约束的最新模型。在这项工作中，我们提出了更大，更快的速度，这是一种新颖的量化参数共享NAS，它为8位整数（INT8）量化变压器的架构。我们的结果表明，我们的方法能够产生胜过当前最新技术的BERT模型，即Autotinybert，我们测试了所有潜伏期目标，达到了2.68％的准确性增益。此外，尽管我们技术发现的模型的参数数量比float32的参数数量更大，但由于其参数为INT8，但它们的内存足迹大大较小。

有限混合物建模是聚类领域的一种流行方法，并且在很大程度上是由于其软聚类成员资格概率所致。但是，EM算法是适合有限混合模型的最常见算法，是许多问题的受害者。我们解决了使用有限混合模型的困扰聚类的这些问题，包括在高维情况下与局部最大值和算法速度问题相对应的解决方案的收敛。这是通过开发两种新型算法来完成的，这些算法结合了数据矩阵的光谱分解和非参数bootstrap采样方案。模拟显示了我们的算法的有效性，不仅证明了它们的灵活性，而且还证明了与其他（自举）聚类算法相比，它们避免了与局部墨西哥相对应的溶液的能力。我们的新型算法通常具有更一致的收敛标准，并且在适合有限混合模型的其他自举算法中，速度显着提高。