用于主动假体或orthoses的控制策略使用传感器输入来识别用户的机车意图,并生成用于产生所需运动的相应控制命令。在本文中,我们提出了一种基于学习的共享模型,用于预测不同运动模式的脚踝关节运动,如Lope-Grouding,Stair Ascent,Stair Descent,Slope Ascent和Slope Descent,而无需在它们之间进行分类。从髋关节和膝关节角运动中提取的特征用于使用前馈神经网络的共享模型连续地预测脚踝角度和矩。我们表明,共享模型足以预测不同运动模式的脚踝角度和时刻,而不明确地在模式之间进行分类。所提出的策略表明,为能够适应不同运动模式的智能假肢脚踝设计高级控制器的可能性。
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Person re-identification is a challenging task because of the high intra-class variance induced by the unrestricted nuisance factors of variations such as pose, illumination, viewpoint, background, and sensor noise. Recent approaches postulate that powerful architectures have the capacity to learn feature representations invariant to nuisance factors, by training them with losses that minimize intra-class variance and maximize inter-class separation, without modeling nuisance factors explicitly. The dominant approaches use either a discriminative loss with margin, like the softmax loss with the additive angular margin, or a metric learning loss, like the triplet loss with batch hard mining of triplets. Since the softmax imposes feature normalization, it limits the gradient flow supervising the feature embedding. We address this by joining the losses and leveraging the triplet loss as a proxy for the missing gradients. We further improve invariance to nuisance factors by adding the discriminative task of predicting attributes. Our extensive evaluation highlights that when only a holistic representation is learned, we consistently outperform the state-of-the-art on the three most challenging datasets. Such representations are easier to deploy in practical systems. Finally, we found that joining the losses removes the requirement for having a margin in the softmax loss while increasing performance.
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A recent explosion of research focuses on developing methods and tools for building fair predictive models. However, most of this work relies on the assumption that the training and testing data are representative of the target population on which the model will be deployed. However, real-world training data often suffer from selection bias and are not representative of the target population for many reasons, including the cost and feasibility of collecting and labeling data, historical discrimination, and individual biases. In this paper, we introduce a new framework for certifying and ensuring the fairness of predictive models trained on biased data. We take inspiration from query answering over incomplete and inconsistent databases to present and formalize the problem of consistent range approximation (CRA) of answers to queries about aggregate information for the target population. We aim to leverage background knowledge about the data collection process, biased data, and limited or no auxiliary data sources to compute a range of answers for aggregate queries over the target population that are consistent with available information. We then develop methods that use CRA of such aggregate queries to build predictive models that are certifiably fair on the target population even when no external information about that population is available during training. We evaluate our methods on real data and demonstrate improvements over state of the art. Significantly, we show that enforcing fairness using our methods can lead to predictive models that are not only fair, but more accurate on the target population.
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Google,Amazon和Microsoft等提供商提供的商业ML API已在许多应用程序中大大简化了ML的采用。许多公司和学者都为使用ML API用于对象检测,OCR和情感分析等任务。处理相同任务的不同ML API可能具有非常异构的性能。此外,API的基础模型也随着时间的推移而发展。随着ML API迅速成为一个有价值的市场,并且是消耗机器学习的广泛方式,因此系统地研究和比较不同的API并表征API随时间变化的方式至关重要。但是,由于缺乏数据,目前该主题目前没有被忽视。在本文中,我们介绍了HAPI(API的历史),该数据集由1,761,417个商业ML API应用程序(涉及来自亚马逊,Google,IBM,Microsoft和其他提供商的API),包括图像标签,文本识别和文本识别和文本识别和文本,从2020年到2022年的挖掘。每个实例都由API的查询输入(例如图像或文本)以及API的输出预测/注释和置信分数组成。 HAPI是ML API使用情况的第一个大型数据集,并且是研究ML-AS-A-Service(MLAAS)的独特资源。作为HAPI启用的分析类型的示例,我们表明ML API的性能会随着时间的流逝而大幅变化 - 在特定基准数据集上删除了几个API的精度。即使API的汇总性能保持稳定,其误差模式也可以在2020年至2022年之间在不同的数据子类型中转移。这种更改可能会大大影响使用某些ML API作为组件的整个分析管道。随着时间的流逝,我们进一步使用HAPI研究人口亚组的商业API绩效差异。 HAPI可以刺激MLAA的不断发展领域的更多研究。
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机器学习(ML)研究通常集中在模型上,而最突出的数据集已用于日常的ML任务,而不考虑这些数据集对基本问题的广度,困难和忠诚。忽略数据集的基本重要性已引起了重大问题,该问题涉及现实世界中的数据级联以及数据集驱动标准的模型质量饱和,并阻碍了研究的增长。为了解决此问题,我们提出Dataperf,这是用于评估ML数据集和数据集工作算法的基准软件包。我们打算启用“数据棘轮”,其中培训集将有助于评估相同问题的测试集,反之亦然。这种反馈驱动的策略将产生一个良性的循环,该循环将加速以数据为中心的AI。MLCommons协会将维护Dataperf。
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无人驾驶飞行器(UAV)是支持各种服务,包括通信的技术突破之一。UAV将在提高无线网络的物理层安全方面发挥关键作用。本文定义了窃听地面用户与UAV之间的链路的问题,该联接器用作空中基站(ABS)。提出了加强学习算法Q - 学习和深Q网络(DQN),用于优化ABS的位置和传输功率,以增强地面用户的数据速率。如果没有系统了解窃听器的位置,这会增加保密容量。与Q-Learnch和基线方法相比,仿真结果显示了拟议DQN的快速收敛性和最高保密能力。
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人工智能(AI)将在蜂窝网络部署,配置和管理中发挥越来越多的作用。本文研究了AI驱动的6G无线电访问网络(RANS)的安全含义。尽管6G标准化的预期时间表仍在数年之外,但与6G安全有关的预标准化工作已经在进行中,并且将受益于基本和实验研究。Open Ran(O-Ran)描述了一个以行业为导向的开放式体系结构和用于使用AI控制的下一代架设的接口。考虑到这种体系结构,我们确定了对数据驱动网络和物理层元素,相应的对策和研究方向的关键威胁。
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