在网络数据中的顶点分类和链接预测等许多问题可以是求象嵌入的曲线图,并且已知许多算法用于构造这种嵌入斑点。但是,难以使用图形来捕获顶点的非二进制关系。这些复杂关系更自然地作为超图。虽然神经图是图形的概括,最先进的图形嵌入技术对于在合理的时间准确地在大型超图上求解预测和分类核对。在本文中,我们介绍了NetVec,这是一种新的多级框架,可用于可扩展的未经监督的超图嵌入,可以使用几分钟内与数百万节点和Hypereed的超图嵌入算法Toproduce嵌入式嵌入式。
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In this paper, we present a novel control architecture for the online adaptation of bipedal locomotion on inclined obstacles. In particular, we introduce a novel, cost-effective, and versatile foot sensor to detect the proximity of the robot's feet to the ground (bump sensor). By employing this sensor, feedback controllers are implemented to reduce the impact forces during the transition of the swing to stance phase or steeping on inclined unseen obstacles. Compared to conventional sensors based on contact reaction force, this sensor detects the distance to the ground or obstacles before the foot touches the obstacle and therefore provides predictive information to anticipate the obstacles. The controller of the proposed bump sensor interacts with another admittance controller to adjust leg length. The walking experiments show successful locomotion on the unseen inclined obstacle without reducing the locomotion speed with a slope angle of 12. Foot position error causes a hard impact with the ground as a consequence of accumulative error caused by links and connections' deflection (which is manufactured by university tools). The proposed framework drastically reduces the feet' impact with the ground.
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The classification of sleep stages plays a crucial role in understanding and diagnosing sleep pathophysiology. Sleep stage scoring relies heavily on visual inspection by an expert that is time consuming and subjective procedure. Recently, deep learning neural network approaches have been leveraged to develop a generalized automated sleep staging and account for shifts in distributions that may be caused by inherent inter/intra-subject variability, heterogeneity across datasets, and different recording environments. However, these networks ignore the connections among brain regions, and disregard the sequential connections between temporally adjacent sleep epochs. To address these issues, this work proposes an adaptive product graph learning-based graph convolutional network, named ProductGraphSleepNet, for learning joint spatio-temporal graphs along with a bidirectional gated recurrent unit and a modified graph attention network to capture the attentive dynamics of sleep stage transitions. Evaluation on two public databases: the Montreal Archive of Sleep Studies (MASS) SS3; and the SleepEDF, which contain full night polysomnography recordings of 62 and 20 healthy subjects, respectively, demonstrates performance comparable to the state-of-the-art (Accuracy: 0.867;0.838, F1-score: 0.818;0.774 and Kappa: 0.802;0.775, on each database respectively). More importantly, the proposed network makes it possible for clinicians to comprehend and interpret the learned connectivity graphs for sleep stages.
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Recently, there has been a significant amount of interest in satellite telemetry anomaly detection (AD) using neural networks (NN). For AD purposes, the current approaches focus on either forecasting or reconstruction of the time series, and they cannot measure the level of reliability or the probability of correct detection. Although the Bayesian neural network (BNN)-based approaches are well known for time series uncertainty estimation, they are computationally intractable. In this paper, we present a tractable approximation for BNN based on the Monte Carlo (MC) dropout method for capturing the uncertainty in the satellite telemetry time series, without sacrificing accuracy. For time series forecasting, we employ an NN, which consists of several Long Short-Term Memory (LSTM) layers followed by various dense layers. We employ the MC dropout inside each LSTM layer and before the dense layers for uncertainty estimation. With the proposed uncertainty region and by utilizing a post-processing filter, we can effectively capture the anomaly points. Numerical results show that our proposed time series AD approach outperforms the existing methods from both prediction accuracy and AD perspectives.
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Graph Learning (GL) is at the core of inference and analysis of connections in data mining and machine learning (ML). By observing a dataset of graph signals, and considering specific assumptions, Graph Signal Processing (GSP) tools can provide practical constraints in the GL approach. One applicable constraint can infer a graph with desired frequency signatures, i.e., spectral templates. However, a severe computational burden is a challenging barrier, especially for inference from high-dimensional graph signals. To address this issue and in the case of the underlying graph having graph product structure, we propose learning product (high dimensional) graphs from product spectral templates with significantly reduced complexity rather than learning them directly from high-dimensional graph signals, which, to the best of our knowledge, has not been addressed in the related areas. In contrast to the rare current approaches, our approach can learn all types of product graphs (with more than two graphs) without knowing the type of graph products and has fewer parameters. Experimental results on both the synthetic and real-world data, i.e., brain signal analysis and multi-view object images, illustrate explainable and meaningful factor graphs supported by expert-related research, as well as outperforming the rare current restricted approaches.
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超声定位显微镜(ULM)是一种采用回声微泡(MB)定位的新兴技术,可对微循环进行精细样品和图像超声成像的衍射极限。常规的MB定位方法主要基于考虑MBS的特定点扩散函数(PSF),这导致由重叠MB,非平稳性PSF和谐波MB回波引起的信息丢失。因此,必须设计可以准确定位MB的方法,同时对MB非线性和扭曲MB PSF的MB浓度的变化有弹性。本文提出了一种基于变压器的MB本地化方法来解决此问题。我们采用了检测变压器(DETR)ARXIV:2005.12872,它是一种端到端对象识别方法,它使用基于集合的匈牙利损失和双方匹配来检测每个检测到的对象的唯一边界框。据作者所知,这是第一次将变形金刚用于MB本地化。为了评估拟议的策略,已经测试了使用转移学习原理检测MBS的预先培训的DETR网络的性能。我们已经在IEEE IUS Ultra-SR挑战组织者提供的随机选择的数据集的随机帧子集上进行了微调,然后使用交叉验证对其余进行测试。对于仿真数据集,本文支持基于变压器的解决方案以高精度为基础的MB本地化。
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过去,现实世界中社交网络的图表错过了两个重要元素:连接的多重性和表示时间。为此,在本文中,我们为社交网络提供了一个新的动态异质图表示,其中包括图形的每个组件中的时间,即节点和边缘,每种捕获异质性的不同类型。我们通过提出四个与时间有关的查询和深度学习问题来说明这种表示的力量,这些查询和深度学习问题无法轻易在常规的均匀图表中处理。作为概念的证明,我们介绍了新的社交媒体平台(Steemit)的详细表示,我们用它来说明动态查询功能以及使用图形神经网络(GNNS)的预测任务。结果说明了动态异质图表示对社交网络的模型的力量。鉴于这是一个相对研究的领域,我们还说明了在查询优化方面的未来工作以及异质图结构的新动态预测任务的机会。
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我们引入了通过随机梯度下降(SGD)来解决鲁棒回归的数据结构,通过对概率与其规范成正比,即重要性采样成正比进行采样。尽管SGD广泛用于大规模机器学习,但由于均匀抽样的较高差异,它可能会经历缓慢的收敛速率而闻名。另一方面,重要性采样可以显着降低差异,但通常很难实施,因为计算采样概率需要对数据进行额外的通过,在这种情况下,可以使用标准梯度下降(GD)。在本文中,我们介绍了一种算法,该算法大约将$ d $ d $ d $ $ d $ d $的算法从$ n $行超过$ n $行的强大回归问题中的最佳重要性采样分布中进行采样。因此,我们的算法在使用sublinear空间时有效地运行了$ t $ t $ sgd,并具有重要的采样,并且只是对数据进行了一次通过。我们的技术还扩展到对二阶优化的重要性采样。
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语言模型既展示了定量的改进,又展示了新的定性功能,随着规模的增加。尽管它们具有潜在的变革性影响,但这些新能力的特征却很差。为了为未来的研究提供信息,为破坏性的新模型能力做准备,并改善社会有害的效果,至关重要的是,我们必须了解目前和近乎未来的能力和语言模型的局限性。为了应对这一挑战,我们介绍了超越模仿游戏基准(Big Bench)。 Big Bench目前由204个任务组成,由132家机构的442位作者贡献。任务主题是多样的,从语言学,儿童发展,数学,常识性推理,生物学,物理学,社会偏见,软件开发等等。 Big-Bench专注于被认为超出当前语言模型的功能的任务。我们评估了OpenAI的GPT型号,Google内部密集变压器体系结构和大型基础上的开关稀疏变压器的行为,跨越了数百万到数十亿个参数。此外,一个人类专家评估者团队执行了所有任务,以提供强大的基准。研究结果包括:模型性能和校准都随规模改善,但绝对的术语(以及与评估者的性能相比);在模型类中的性能非常相似,尽管带有稀疏性。逐渐和预测的任务通常涉及大量知识或记忆成分,而在临界规模上表现出“突破性”行为的任务通常涉及多个步骤或组成部分或脆性指标;社交偏见通常会随着含糊不清的环境而随着规模而增加,但这可以通过提示来改善。
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常规监督学习或分类的主要假设是,测试样本是从与训练样本相同的分布中得出的,该样本称为封闭设置学习或分类。在许多实际情况下,事实并非如此,因为测试数据中有未知数或看不见的类样本,这称为“开放式”方案,需要检测到未知数。该问题称为开放式识别问题,在安全至关重要的应用中很重要。我们建议通过学习成对相似性来检测未知数(或看不见的类样本)。提出的方法分为两个步骤。它首先使用培训中出现的所见类学习了一个封闭的集体分类器,然后学习如何将看到的类与伪单人(自动生成的看不见的类样本)进行比较。伪无表情的一代是通过对可见或训练样品进行分配转换增加而进行的。我们称我们的方法OPG(基于伪看不见的数据生成开放式识别)。实验评估表明,基于相似性的功能可以成功区分基准数据集中的未见特征,以进行开放式识别。
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