Although weakly-supervised techniques can reduce the labeling effort, it is unclear whether a saliency model trained with weakly-supervised data (e.g., point annotation) can achieve the equivalent performance of its fully-supervised version. This paper attempts to answer this unexplored question by proving a hypothesis: there is a point-labeled dataset where saliency models trained on it can achieve equivalent performance when trained on the densely annotated dataset. To prove this conjecture, we proposed a novel yet effective adversarial trajectory-ensemble active learning (ATAL). Our contributions are three-fold: 1) Our proposed adversarial attack triggering uncertainty can conquer the overconfidence of existing active learning methods and accurately locate these uncertain pixels. {2)} Our proposed trajectory-ensemble uncertainty estimation method maintains the advantages of the ensemble networks while significantly reducing the computational cost. {3)} Our proposed relationship-aware diversity sampling algorithm can conquer oversampling while boosting performance. Experimental results show that our ATAL can find such a point-labeled dataset, where a saliency model trained on it obtained $97\%$ -- $99\%$ performance of its fully-supervised version with only ten annotated points per image.
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Nesterov's accelerated gradient descent (NAG) is one of the milestones in the history of first-order algorithms. It was not successfully uncovered until the high-resolution differential equation framework was proposed in [Shi et al., 2022] that the mechanism behind the acceleration phenomenon is due to the gradient correction term. To deepen our understanding of the high-resolution differential equation framework on the convergence rate, we continue to investigate NAG for the $\mu$-strongly convex function based on the techniques of Lyapunov analysis and phase-space representation in this paper. First, we revisit the proof from the gradient-correction scheme. Similar to [Chen et al., 2022], the straightforward calculation simplifies the proof extremely and enlarges the step size to $s=1/L$ with minor modification. Meanwhile, the way of constructing Lyapunov functions is principled. Furthermore, we also investigate NAG from the implicit-velocity scheme. Due to the difference in the velocity iterates, we find that the Lyapunov function is constructed from the implicit-velocity scheme without the additional term and the calculation of iterative difference becomes simpler. Together with the optimal step size obtained, the high-resolution differential equation framework from the implicit-velocity scheme of NAG is perfect and outperforms the gradient-correction scheme.
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The hyperparameter optimization of neural network can be expressed as a bilevel optimization problem. The bilevel optimization is used to automatically update the hyperparameter, and the gradient of the hyperparameter is the approximate gradient based on the best response function. Finding the best response function is very time consuming. In this paper we propose CPMLHO, a new hyperparameter optimization method using cutting plane method and mixed-level objective function.The cutting plane is added to the inner layer to constrain the space of the response function. To obtain more accurate hypergradient,the mixed-level can flexibly adjust the loss function by using the loss of the training set and the verification set. Compared to existing methods, the experimental results show that our method can automatically update the hyperparameters in the training process, and can find more superior hyperparameters with higher accuracy and faster convergence.
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Aspect Sentiment Triplet Extraction (ASTE) has become an emerging task in sentiment analysis research, aiming to extract triplets of the aspect term, its corresponding opinion term, and its associated sentiment polarity from a given sentence. Recently, many neural networks based models with different tagging schemes have been proposed, but almost all of them have their limitations: heavily relying on 1) prior assumption that each word is only associated with a single role (e.g., aspect term, or opinion term, etc. ) and 2) word-level interactions and treating each opinion/aspect as a set of independent words. Hence, they perform poorly on the complex ASTE task, such as a word associated with multiple roles or an aspect/opinion term with multiple words. Hence, we propose a novel approach, Span TAgging and Greedy infErence (STAGE), to extract sentiment triplets in span-level, where each span may consist of multiple words and play different roles simultaneously. To this end, this paper formulates the ASTE task as a multi-class span classification problem. Specifically, STAGE generates more accurate aspect sentiment triplet extractions via exploring span-level information and constraints, which consists of two components, namely, span tagging scheme and greedy inference strategy. The former tag all possible candidate spans based on a newly-defined tagging set. The latter retrieves the aspect/opinion term with the maximum length from the candidate sentiment snippet to output sentiment triplets. Furthermore, we propose a simple but effective model based on the STAGE, which outperforms the state-of-the-arts by a large margin on four widely-used datasets. Moreover, our STAGE can be easily generalized to other pair/triplet extraction tasks, which also demonstrates the superiority of the proposed scheme STAGE.
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隐式神经表示显示了3D场景重建的有希望的潜力。最近的工作将其应用于自主3D重建,通过学习信息获得图路径计划的信息增益。有效,信息增益的计算很昂贵,并且与使用体积表示相比,使用隐式表示为3D点进行碰撞检查要慢得多。在本文中,我们建议1)利用神经网络作为信息增益场的隐式函数近似器,以及2)将隐式细粒表示与粗量表示形式结合起来,以提高效率。随着效率的提高,我们提出了基于基于图的计划者的新型信息路径计划。我们的方法表明,与具有隐性和明确表示的自主重建相比,重建质量和计划效率的显着提高。我们将该方法部署在真正的无人机上,结果表明我们的方法可以计划信息意见并以高质量重建场景。
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基于学习的控制器,例如神经网络(NN)控制器,可以表现出很高的经验性能,但缺乏正式的安全保证。为了解决此问题,已将控制屏障功能(CBF)应用于安全过滤器,以监视和修改基于学习的控制器的输出,以确保闭环系统的安全性。但是,这种修饰可能是近视的,具有不可预测的长期影响。在这项工作中,我们提出了一个安全的NN控制器,该控制器采用了基于CBF的可区分安全层,并研究了基于学习的控制中安全的NN控制器的性能。具体而言,比较了两个控制器的公式:一个是基于投影的,另一个依赖于我们提出的集合理论参数化。两种方法都证明了在数值实验中使用CBF作为单独的安全滤波器的改进的闭环性能。
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在一阶算法的历史中,Nesterov的加速梯度下降(NAG)是里程碑之一。但是,长期以来,加速的原因一直是一个谜。直到[Shi等,2021]中提出的高分辨率微分方程框架之前,梯度校正的存在尚未得到揭示。在本文中,我们继续研究加速现象。首先,我们基于精确的观察结果和$ L $ SMOTH功能的不等式提供了明显的简化证明。然后,提出了一个新的隐式高分辨率差分方程框架,以及相应的隐式 - 速度版本的相位空间表示和lyapunov函数,以研究迭代序列$ \ {x_k \} _的迭代序列的收敛行为{k = 0}^{\ infty} $的nag。此外,从两种类型的相空间表示形式中,我们发现梯度校正所起的作用等同于按速度隐含在梯度中包含的作用,其中唯一的区别来自迭代序列$ \ \ {y_ {y_ {k} \} _ {k = 0}^{\ infty} $由$ \ {x_k \} _ {k = 0}^{\ infty} $代替。最后,对于NAG的梯度规范最小化是否具有更快的速率$ O(1/K^3)$的开放问题,我们为证明提供了一个积极的答案。同时,为$ r> 2 $显示了目标值最小化$ o(1/k^2)$的更快的速度。
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光学相干断层扫描(OCT)是一种非侵入性技术,可在微米分辨率中捕获视网膜的横截面区域。它已被广泛用作辅助成像参考,以检测与眼睛有关的病理学并预测疾病特征的纵向进展。视网膜层分割是至关重要的特征提取技术之一,其中视网膜层厚度的变化和由于液体的存在而引起的视网膜层变形高度相关,与多种流行性眼部疾病(如糖尿病性视网膜病)和年龄相关的黄斑疾病高度相关。变性(AMD)。但是,这些图像是从具有不同强度分布或换句话说的不同设备中获取的,属于不同的成像域。本文提出了一种分割引导的域适应方法,以将来自多个设备的图像调整为单个图像域,其中可用的最先进的预训练模型可用。它避免了即将推出的新数据集的手动标签的时间消耗以及现有网络的重新培训。网络的语义一致性和全球特征一致性将最大程度地减少许多研究人员报告的幻觉效果,这些效应对周期矛盾的生成对抗网络(Cyclegan)体系结构。
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从搜索效率中受益,可区分的神经体系结构搜索(NAS)已发展为自动设计竞争性深神经网络(DNNS)的最主要替代品。我们注意到,必须在现实世界中严格的性能限制下执行DNN,例如,自动驾驶汽车的运行时间延迟。但是,要获得符合给定性能限制的体系结构,先前的硬件可区分的NAS方法必须重复多次搜索运行,以通过反复试验和错误手动调整超参数,因此总设计成本会成比例地增加。为了解决这个问题,我们引入了一个轻巧的硬件可区分的NAS框架,称为lightnas,努力找到所需的架构,通过一次性搜索来满足各种性能约束(即,\ \ suesperline {\ textIt {您只搜索一次}})) 。进行了广泛的实验,以显示LINDNA的优越性,而不是先前的最新方法。
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这项工作提出了一种有丝分裂检测方法,只有一个香草卷积神经网络(CNN)。我们的方法由两个步骤组成:给定图像,我们首先使用滑动窗口技术应用CNN来提取具有有丝分裂的斑块。然后,我们计算每个提取的斑块的类激活图,以获得有丝分裂的精确位置。为了提高模型的推广性,我们使用一系列数据增强技术训练CNN,与噪声标记的图像相抵制的损失以及主动的学习策略。我们的方法在MIDOG 2022挑战的初步测试阶段中,通过有效网络B3模型获得了0.7323的F1得分。
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