在全球范围内消除语言障碍的目标的驱动下,机器翻译已巩固自己是当今人工智能研究的关键重点。但是,这样的努力围绕着一小部分语言结合在一起,留下了绝大多数低资源的语言。在确保安全,高质量的结果的同时,在牢记道德考虑的同时,打破200个语言障碍需要什么?没有留下的语言,我们首先通过与母语人士的探索性访谈来解决对低资源语言翻译支持的必要性来应对这一挑战。然后,我们创建了旨在缩小低资源和高资源语言之间的性能差距的数据集和模型。更具体地说,我们开发了一种有条件的计算模型,基于专家的稀疏混合物,该模型经过针对针对低资源语言量身定制的新颖有效的数据挖掘技术培训的。我们提出了多次建筑和培训改进,以抵消数千个任务的培训。至关重要的是,我们使用人类翻译的基准,Flores-200评估了40,000多种不同的翻译方向的性能,并将人类评估与新型毒性基准相结合,涵盖Flores-200的所有语言,以评估翻译安全性。我们的模型相对于先前的最新技术,实现了44%BLEU的改善,为实现通用翻译系统奠定了重要的基础。最后,我们开源此工作中描述的所有贡献,可在https://github.com/facebookresearch/fairseq/tree/nllb上访问。
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深度学习(DL)模型为各种医学成像基准挑战提供了最先进的性能,包括脑肿瘤细分(BRATS)挑战。然而,局灶性病理多隔室分割(例如,肿瘤和病变子区)的任务特别具有挑战性,并且潜在的错误阻碍DL模型转化为临床工作流程。量化不确定形式的DL模型预测的可靠性,可以实现最不确定的地区的临床审查,从而建立信任并铺平临床翻译。最近,已经引入了许多不确定性估计方法,用于DL医学图像分割任务。开发指标评估和比较不确定性措施的表现将有助于最终用户制定更明智的决策。在本研究中,我们探索并评估在Brats 2019-2020任务期间开发的公制,以对不确定量化量化(Qu-Brats),并旨在评估和排列脑肿瘤多隔室分割的不确定性估计。该公制(1)奖励不确定性估计,对正确断言产生高置信度,以及在不正确的断言处分配低置信水平的估计数,(2)惩罚导致更高百分比的无关正确断言百分比的不确定性措施。我们进一步基准测试由14个独立参与的Qu-Brats 2020的分割不确定性,所有这些都参与了主要的Brats细分任务。总体而言,我们的研究结果证实了不确定性估计提供了分割算法的重要性和互补价值,因此突出了医学图像分析中不确定性量化的需求。我们的评估代码在HTTPS://github.com/ragmeh11/qu-brats公开提供。
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串联连接的机器人是希望在大规模灾害中的搜索和救援等限制空间中执行任务的候选人。这种机器人通常是韧带,我们假设肢体的添加可以改善移动性。然而,在设计和控制这种装置方面的挑战在于以提高移动性的方式协调高维冗余模块。在这里,我们开发了一个控制串联连接的多腿机器人的一般框架。具体地,我们结合了两种方法来构建一般的形状控制方案,其可以为各种机器人形态的有效运动提供自变形(“Gaits”)的基线模式。首先,我们从维度降低和生物步态分类方案中获取灵感,以产生身体变形和脚提升/降低的循环模式,其促进了任意基板接触图案的产生。其次,我们使用几何力学方法来促进识别这些起伏的最佳相位,以最大化速度和/或稳定性。我们的方案允许在扁平摩擦地形上的多腿机器人机车上的有效Gaits开发有多种数量的四肢(4,6,16,甚至0四肢)和身体致动能力(包括在Limbless设备上的侧壁Gaits)。通过适当协调身体波动和腿部放置,我们的框架结合了Limbless机器人(模块化)和腿机器人(移动性)的优势。我们预计我们的框架可以提供一般的控制方案,以便快速部署一般的多腿机器人,铺平往达在现实条件下遍历复杂环境的机器的方式。
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我们提供匹配的Under $ \ sigma ^ 2 / \ log(d / n)$的匹配的上下界限为最低$ \ ell_1 $ -norm插值器,a.k.a.基础追踪。我们的结果紧紧达到可忽略的术语,而且是第一个暗示噪声最小范围内插值的渐近一致性,因为各向同性特征和稀疏的地面真理。我们的工作对最低$ \ ell_2 $ -norm插值的“良性接收”进行了补充文献,其中才能在特征有效地低维时实现渐近一致性。
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拟合网络模型到神经活动是神经科学的重要工具。一种流行的方法是利用概率经常性尖刺网络来模拟大脑区域,其参数最大化记录的活动的可能性。虽然这是广泛使用的,但我们表明所得模型不会产生现实的神经活动。要纠正此功能,我们建议使用测量模拟和录制活动之间的异化的术语来增加日志可能性。这种不相似性通过神经科学常用的概要统计来定义,并且优化是有效的,因为它依赖于通过随机模拟的尖峰列车的背部传播。理论上我们分析了这种方法,并经验展示它产生更现实的活动统计数据。我们发现它可以改善其他拟合算法,用于尖刺网络模型,如GLM(广义线性模型),通常不依赖于反向传播。这种新的拟合算法还使得能够考虑难以苛刻的隐藏神经元,并且我们表明在尝试从尖峰录制中推断网络连接时可能是至关重要的。
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In this paper, we present a framework for learning quadruped navigation by integrating central pattern generators (CPGs), i.e. systems of coupled oscillators, into the deep reinforcement learning (DRL) framework. Through both exteroceptive and proprioceptive sensing, the agent learns to modulate the intrinsic oscillator setpoints (amplitude and frequency) and coordinate rhythmic behavior among different oscillators to track velocity commands while avoiding collisions with the environment. We compare different neural network architectures (i.e. memory-free and memory-enabled) which learn implicit interoscillator couplings, as well as varying the strength of the explicit coupling weights in the oscillator dynamics equations. We train our policies in simulation and perform a sim-to-real transfer to the Unitree Go1 quadruped, where we observe robust navigation in a variety of scenarios. Our results show that both memory-enabled policy representations and explicit interoscillator couplings are beneficial for a successful sim-to-real transfer for navigation tasks. Video results can be found at https://youtu.be/O_LX1oLZOe0.
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Deep spiking neural networks (SNNs) offer the promise of low-power artificial intelligence. However, training deep SNNs from scratch or converting deep artificial neural networks to SNNs without loss of performance has been a challenge. Here we propose an exact mapping from a network with Rectified Linear Units (ReLUs) to an SNN that fires exactly one spike per neuron. For our constructive proof, we assume that an arbitrary multi-layer ReLU network with or without convolutional layers, batch normalization and max pooling layers was trained to high performance on some training set. Furthermore, we assume that we have access to a representative example of input data used during training and to the exact parameters (weights and biases) of the trained ReLU network. The mapping from deep ReLU networks to SNNs causes zero percent drop in accuracy on CIFAR10, CIFAR100 and the ImageNet-like data sets Places365 and PASS. More generally our work shows that an arbitrary deep ReLU network can be replaced by an energy-efficient single-spike neural network without any loss of performance.
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Recently, extensive studies on photonic reinforcement learning to accelerate the process of calculation by exploiting the physical nature of light have been conducted. Previous studies utilized quantum interference of photons to achieve collective decision-making without choice conflicts when solving the competitive multi-armed bandit problem, a fundamental example of reinforcement learning. However, the bandit problem deals with a static environment where the agent's action does not influence the reward probabilities. This study aims to extend the conventional approach to a more general multi-agent reinforcement learning targeting the grid world problem. Unlike the conventional approach, the proposed scheme deals with a dynamic environment where the reward changes because of agents' actions. A successful photonic reinforcement learning scheme requires both a photonic system that contributes to the quality of learning and a suitable algorithm. This study proposes a novel learning algorithm, discontinuous bandit Q-learning, in view of a potential photonic implementation. Here, state-action pairs in the environment are regarded as slot machines in the context of the bandit problem and an updated amount of Q-value is regarded as the reward of the bandit problem. We perform numerical simulations to validate the effectiveness of the bandit algorithm. In addition, we propose a multi-agent architecture in which agents are indirectly connected through quantum interference of light and quantum principles ensure the conflict-free property of state-action pair selections among agents. We demonstrate that multi-agent reinforcement learning can be accelerated owing to conflict avoidance among multiple agents.
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Fingerprints are key tools in climate change detection and attribution (D&A) that are used to determine whether changes in observations are different from internal climate variability (detection), and whether observed changes can be assigned to specific external drivers (attribution). We propose a direct D&A approach based on supervised learning to extract fingerprints that lead to robust predictions under relevant interventions on exogenous variables, i.e., climate drivers other than the target. We employ anchor regression, a distributionally-robust statistical learning method inspired by causal inference that extrapolates well to perturbed data under the interventions considered. The residuals from the prediction achieve either uncorrelatedness or mean independence with the exogenous variables, thus guaranteeing robustness. We define D&A as a unified hypothesis testing framework that relies on the same statistical model but uses different targets and test statistics. In the experiments, we first show that the CO2 forcing can be robustly predicted from temperature spatial patterns under strong interventions on the solar forcing. Second, we illustrate attribution to the greenhouse gases and aerosols while protecting against interventions on the aerosols and CO2 forcing, respectively. Our study shows that incorporating robustness constraints against relevant interventions may significantly benefit detection and attribution of climate change.
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We discuss pattern languages for closed pattern mining and learning of interval data and distributional data. We first introduce pattern languages relying on pairs of intersection-based constraints or pairs of inclusion based constraints, or both, applied to intervals. We discuss the encoding of such interval patterns as itemsets thus allowing to use closed itemsets mining and formal concept analysis programs. We experiment these languages on clustering and supervised learning tasks. Then we show how to extend the approach to address distributional data.
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