To date, little attention has been given to multi-view 3D human mesh estimation, despite real-life applicability (e.g., motion capture, sport analysis) and robustness to single-view ambiguities. Existing solutions typically suffer from poor generalization performance to new settings, largely due to the limited diversity of image-mesh pairs in multi-view training data. To address this shortcoming, people have explored the use of synthetic images. But besides the usual impact of visual gap between rendered and target data, synthetic-data-driven multi-view estimators also suffer from overfitting to the camera viewpoint distribution sampled during training which usually differs from real-world distributions. Tackling both challenges, we propose a novel simulation-based training pipeline for multi-view human mesh recovery, which (a) relies on intermediate 2D representations which are more robust to synthetic-to-real domain gap; (b) leverages learnable calibration and triangulation to adapt to more diversified camera setups; and (c) progressively aggregates multi-view information in a canonical 3D space to remove ambiguities in 2D representations. Through extensive benchmarking, we demonstrate the superiority of the proposed solution especially for unseen in-the-wild scenarios.
translated by 谷歌翻译
The interplay between quantum physics and machine learning gives rise to the emergent frontier of quantum machine learning, where advanced quantum learning models may outperform their classical counterparts in solving certain challenging problems. However, quantum learning systems are vulnerable to adversarial attacks: adding tiny carefully-crafted perturbations on legitimate input samples can cause misclassifications. To address this issue, we propose a general scheme to protect quantum learning systems from adversarial attacks by randomly encoding the legitimate data samples through unitary or quantum error correction encoders. In particular, we rigorously prove that both global and local random unitary encoders lead to exponentially vanishing gradients (i.e. barren plateaus) for any variational quantum circuits that aim to add adversarial perturbations, independent of the input data and the inner structures of adversarial circuits and quantum classifiers. In addition, we prove a rigorous bound on the vulnerability of quantum classifiers under local unitary adversarial attacks. We show that random black-box quantum error correction encoders can protect quantum classifiers against local adversarial noises and their robustness increases as we concatenate error correction codes. To quantify the robustness enhancement, we adapt quantum differential privacy as a measure of the prediction stability for quantum classifiers. Our results establish versatile defense strategies for quantum classifiers against adversarial perturbations, which provide valuable guidance to enhance the reliability and security for both near-term and future quantum learning technologies.
translated by 谷歌翻译
Long short-term memory (LSTM) is a type of powerful deep neural network that has been widely used in many sequence analysis and modeling applications. However, the large model size problem of LSTM networks make their practical deployment still very challenging, especially for the video recognition tasks that require high-dimensional input data. Aiming to overcome this limitation and fully unlock the potentials of LSTM models, in this paper we propose to perform algorithm and hardware co-design towards high-performance energy-efficient LSTM networks. At algorithm level, we propose to develop fully decomposed hierarchical Tucker (FDHT) structure-based LSTM, namely FDHT-LSTM, which enjoys ultra-low model complexity while still achieving high accuracy. In order to fully reap such attractive algorithmic benefit, we further develop the corresponding customized hardware architecture to support the efficient execution of the proposed FDHT-LSTM model. With the delicate design of memory access scheme, the complicated matrix transformation can be efficiently supported by the underlying hardware without any access conflict in an on-the-fly way. Our evaluation results show that both the proposed ultra-compact FDHT-LSTM models and the corresponding hardware accelerator achieve very high performance. Compared with the state-of-the-art compressed LSTM models, FDHT-LSTM enjoys both order-of-magnitude reduction in model size and significant accuracy improvement across different video recognition datasets. Meanwhile, compared with the state-of-the-art tensor decomposed model-oriented hardware TIE, our proposed FDHT-LSTM architecture achieves better performance in throughput, area efficiency and energy efficiency, respectively on LSTM-Youtube workload. For LSTM-UCF workload, our proposed design also outperforms TIE with higher throughput, higher energy efficiency and comparable area efficiency.
translated by 谷歌翻译
Recently, a surge of high-quality 3D-aware GANs have been proposed, which leverage the generative power of neural rendering. It is natural to associate 3D GANs with GAN inversion methods to project a real image into the generator's latent space, allowing free-view consistent synthesis and editing, referred as 3D GAN inversion. Although with the facial prior preserved in pre-trained 3D GANs, reconstructing a 3D portrait with only one monocular image is still an ill-pose problem. The straightforward application of 2D GAN inversion methods focuses on texture similarity only while ignoring the correctness of 3D geometry shapes. It may raise geometry collapse effects, especially when reconstructing a side face under an extreme pose. Besides, the synthetic results in novel views are prone to be blurry. In this work, we propose a novel method to promote 3D GAN inversion by introducing facial symmetry prior. We design a pipeline and constraints to make full use of the pseudo auxiliary view obtained via image flipping, which helps obtain a robust and reasonable geometry shape during the inversion process. To enhance texture fidelity in unobserved viewpoints, pseudo labels from depth-guided 3D warping can provide extra supervision. We design constraints aimed at filtering out conflict areas for optimization in asymmetric situations. Comprehensive quantitative and qualitative evaluations on image reconstruction and editing demonstrate the superiority of our method.
translated by 谷歌翻译
Three-phase PWM voltage-source rectifier (VSR) systems have been widely used in various energy conversion systems, where current sensors are the key component for state monitoring and system control. The current sensor faults may bring hidden danger or damage to the whole system; therefore, this paper proposed a random forest (RF) and current fault texture feature-based method for current sensor fault diagnosis in three-phase PWM VSR systems. First, the three-phase alternating currents (ACs) of the three-phase PWM VSR are collected to extract the current fault texture features, and no additional hardware sensors are needed to avoid causing additional unstable factors. Then, the current fault texture features are adopted to train the random forest current sensor fault detection and diagnosis (CSFDD) classifier, which is a data-driven CSFDD classifier. Finally, the effectiveness of the proposed method is verified by simulation experiments. The result shows that the current sensor faults can be detected and located successfully and that it can effectively provide fault locations for maintenance personnel to keep the stable operation of the whole system.
translated by 谷歌翻译
Controller design for bipedal walking on dynamic rigid surfaces (DRSes), which are rigid surfaces moving in the inertial frame (e.g., ships and airplanes), remains largely uninvestigated. This paper introduces a hierarchical control approach that achieves stable underactuated bipedal robot walking on a horizontally oscillating DRS. The highest layer of our approach is a real-time motion planner that generates desired global behaviors (i.e., the center of mass trajectories and footstep locations) by stabilizing a reduced-order robot model. One key novelty of this layer is the derivation of the reduced-order model by analytically extending the angular momentum based linear inverted pendulum (ALIP) model from stationary to horizontally moving surfaces. The other novelty is the development of a discrete-time foot-placement controller that exponentially stabilizes the hybrid, linear, time-varying ALIP model. The middle layer of the proposed approach is a walking pattern generator that translates the desired global behaviors into the robot's full-body reference trajectories for all directly actuated degrees of freedom. The lowest layer is an input-output linearizing controller that exponentially tracks those full-body reference trajectories based on the full-order, hybrid, nonlinear robot dynamics. Simulations of planar underactuated bipedal walking on a swaying DRS confirm that the proposed framework ensures the walking stability under different DRS motions and gait types.
translated by 谷歌翻译
了解动态场景中的3D运动对于许多视觉应用至关重要。最近的进步主要集中在估计人类等某些特定元素的活动上。在本文中,我们利用神经运动场来估计多视图设置中所有点的运动。由于颜色相似的点和与时变颜色的点的歧义,从动态场景中对动态场景进行建模运动是具有挑战性的。我们建议将估计运动的正规化为可预测。如果已知来自以前的帧的运动,那么在不久的将来的运动应该是可以预测的。因此,我们通过首先调节潜在嵌入的估计运动来引入可预测性正则化,然后通过采用预测网络来在嵌入式上执行可预测性。所提出的框架pref(可预测性正则化字段)比基于最先进的神经运动场的动态场景表示方法在PAR或更好的结果上取得了更好的成绩,同时不需要对场景的先验知识。
translated by 谷歌翻译
持续学习的现有工作(CL)的重点是减轻灾难性遗忘,即学习新任务时过去任务的模型绩效恶化。但是,CL系统的训练效率不足,这限制了CL系统在资源有限的方案下的现实应用。在这项工作中,我们提出了一个名为“稀疏持续学习”(SPARCL)的新颖框架,这是第一个利用稀疏性以使边缘设备上具有成本效益的持续学习的研究。 SPARCL通过三个方面的协同作用来实现训练加速度和准确性保护:体重稀疏性,数据效率和梯度稀疏性。具体而言,我们建议在整个CL过程中学习一个稀疏网络,动态数据删除(DDR),以删除信息较少的培训数据和动态梯度掩盖(DGM),以稀疏梯度更新。他们每个人不仅提高了效率,而且进一步减轻了灾难性的遗忘。 SPARCL始终提高现有最新CL方法(SOTA)CL方法的训练效率最多减少了训练失败,而且令人惊讶的是,SOTA的准确性最多最多提高了1.7%。 SPARCL还优于通过将SOTA稀疏训练方法适应CL设置的效率和准确性获得的竞争基线。我们还评估了SPARCL在真实手机上的有效性,进一步表明了我们方法的实际潜力。
translated by 谷歌翻译
点云完成旨在从部分点云中恢复原始形状信息,引起了人们对3D Vision社区的关注。现有方法通常成功完成标准形状,同时未能生成某些非标准形状的点云的本地细节。为了获得理想的当地细节,全球形状信息的指导至关重要。在这项工作中,我们设计了一种有效的方法来借助类内部形状的原型表示区分标准/非标准形状,可以通过建议的监督形状聚类借口任务来计算,从而导致异构组件W.R.T完成网络。代表性的原型(定义为形状类别的特征质心)可以提供全局形状的指导,该指南被称为软性知识,以多尺度方式通过所需的选择性感知特征融合模块注入下游完成网络。此外,要进行有效的培训,我们考虑了基于困难的采样策略,以鼓励网络更多地关注一些部分点云,而几何信息较少。实验结果表明,我们的方法表现优于其他最新方法,并且具有完成复杂几何形状的强大能力。
translated by 谷歌翻译
知识蒸馏(KD)已广泛发展并增强了各种任务。经典的KD方法将KD损失添加到原始的跨熵(CE)损失中。我们尝试分解KD损失,以探索其与CE损失的关系。令人惊讶的是,我们发现它可以被视为CE损失和额外损失的组合,其形式与CE损失相同。但是,我们注意到额外的损失迫使学生学习教师绝对概率的相对可能性。此外,这两个概率的总和是不同的,因此很难优化。为了解决这个问题,我们修改了配方并提出分布式损失。此外,我们将教师的目标输出作为软目标,提出软损失。结合软损失和分布式损失,我们提出了新的KD损失(NKD)。此外,我们将学生的目标输出稳定,将其视为无需教师的培训的软目标,并提出了无教师的新KD损失(TF-NKD)。我们的方法在CIFAR-100和Imagenet上实现了最先进的性能。例如,以Resnet-34为老师,我们将Imagenet TOP-1的RESNET18的TOP-1精度从69.90%提高到71.96%。在没有教师的培训中,Mobilenet,Resnet-18和Swintransformer-tiny的培训占70.04%,70.76%和81.48%,分别比基线高0.83%,0.86%和0.30%。该代码可在https://github.com/yzd-v/cls_kd上找到。
translated by 谷歌翻译