这项工作介绍了模型预测控制(MPC)的公式,该公式适应基于任务的模型的复杂性,同时保持可行性和稳定性保证。现有的MPC实现通常通过缩短预测范围或简化模型来处理计算复杂性,这两者都可能导致不稳定。受到行为经济学,运动计划和生物力学相关方法的启发,我们的方法通过简单模型解决了MPC问题,用于在地平线区域的动力学和约束,而这种模型是可行的,并且不存在该模型的复杂模型。该方法利用计划和执行的交织来迭代识别这些区域,如果它们满足确切的模板/锚关系,可以安全地简化这些区域。我们表明,该方法不会损害系统的稳定性和可行性特性,并在仿真实验中衡量在四足动物上执行敏捷行为的仿真实验中的性能。我们发现,与固定复杂性实现相比,这种自适应方法可以实现更多的敏捷运动,并扩大可执行任务的范围。
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As social media grows faster, harassment becomes more prevalent which leads to considered fake detection a fascinating field among researchers. The graph nature of data with the large number of nodes caused different obstacles including a considerable amount of unrelated features in matrices as high dispersion and imbalance classes in the dataset. To deal with these issues Auto-encoders and a combination of semi-supervised learning and the GAN algorithm which is called SGAN were used. This paper is deploying a smaller number of labels and applying SGAN as a classifier. The result of this test showed that the accuracy had reached 91\% in detecting fake accounts using only 100 labeled samples.
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Distributing machine learning predictors enables the collection of large-scale datasets while leaving sensitive raw data at trustworthy sites. We show that locally training support vector machines (SVMs) and computing their averages leads to a learning technique that is scalable to a large number of users, satisfies differential privacy, and is applicable to non-trivial tasks, such as CIFAR-10. For a large number of participants, communication cost is one of the main challenges. We achieve a low communication cost by requiring only a single invocation of an efficient secure multiparty summation protocol. By relying on state-of-the-art feature extractors (SimCLR), we are able to utilize differentially private convex learners for non-trivial tasks such as CIFAR-10. Our experimental results illustrate that for $1{,}000$ users with $50$ data points each, our scheme outperforms state-of-the-art scalable distributed learning methods (differentially private federated learning, short DP-FL) while requiring around $500$ times fewer communication costs: For CIFAR-10, we achieve a classification accuracy of $79.7\,\%$ for an $\varepsilon = 0.59$ while DP-FL achieves $57.6\,\%$. More generally, we prove learnability properties for the average of such locally trained models: convergence and uniform stability. By only requiring strongly convex, smooth, and Lipschitz-continuous objective functions, locally trained via stochastic gradient descent (SGD), we achieve a strong utility-privacy tradeoff.
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这项工作考虑了嵌套形式的功能组成优化,而每个函数都包含期望。这种类型的问题是在诸如增强学习中的策略评估或元学习中的模型定制中越来越受欢迎。不能直接应用用于非复合优化的标准riemannian随机梯度方法,因为内部功能的随机近似在外部函数的梯度中造成了偏见。为了进行两级组成优化,我们提出了一个Riemannian随机成分梯度下降(R-SCGD)方法,该方法找到了一个近似的固定点,预期平方的Riemannian梯度小于$ \ epsilon $,in $ O(\ epsilon^{-2 {-2) })$调用内部功能的外部功能和随机函数的随机梯度甲骨文的呼叫。此外,我们将R-SCGD算法概括为多层嵌套组成结构的问题,对于一阶随机甲骨文而言,具有$ O(\ epsilon^{ - 2})$的复杂性相同。最后,对R-SCGD方法的性能进行了数值评估,该方法在强化学习中的策略评估问题上进行了数值评估。
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许多日常活动和心理物理实验涉及在工作记忆中保持多个项目。当物品采用连续值(例如,方向,对比度,长度,响度),它们必须以适当的尺寸的连续结构存储。我们调查如何通过培训经常性网络在神经电路中在神经电路中提出两个先前显示的刺激取向。我们发现两个方向的活动歧管类似于克利福德·托鲁斯。虽然夹层和标准圆环(甜甜圈的表面)是拓扑相当的,但它们具有重要的功能差异。克利福德·托鲁斯平等地对待两种方向,并使它们保持在正交子空间中,如任务所要求的,而标准的圆环没有。我们发现并表征了支持Clifford Torus的连接模式。此外,除了通过持久性活动存储信息的吸引子之外,我们的网络还使用动态代码,其中单位改变调谐以防止新的感官输入覆盖先前存储的输入。我们认为,每当多个输入通过共享连接输入存储器系统时,通常需要这种动态代码。最后,我们将我们的框架应用于人类心理物理学实验,其中受试者报告了两个记忆的方向。通过改变RNN的培训条件,我们测试和支持人类行为是神经噪声的产物的假设,并且依赖于两个取向之间的序数关系的更稳定和行为相关的记忆。这表明RNNS中的合适的归纳偏差对于揭示人脑如何实现工作记忆很重要。这些结果在一起,了解了一类视觉解码任务的神经计算,从人类行为缩小到突触连接。
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