成像生物标志物提供了一种无创的方法来预测治疗前免疫疗法的反应。在这项工作中，我们提出了一种从卷积神经网络（CNN）计算出的新型深度放射素特征（DRF），该特征捕获了与免疫细胞标记和整体生存有关的肿瘤特征。我们的研究使用四个MRI序列（T1加权，T1加权后对比，T2加权和FLAIR），并具有151例脑肿瘤患者的相应免疫细胞标记。该方法通过在MRI扫描的标记肿瘤区域内聚集了预训练的3D-CNN的激活图，从而提取了180个DRF。这些功能提供了编码组织异质性的区域纹理的紧凑而有力的表示。进行了一组全面的实验，以评估所提出的DRF和免疫细胞标记之间的关系，并衡量它们与整体生存的关联。结果表明，DRF和各种标记之间存在很高的相关性，以及根据这些标记分组的患者之间的显着差异。此外，将DRF，临床特征和免疫细胞标记组合为随机森林分类器的输入有助于区分短期和长期生存结果，AUC为72 \％，P = 2.36 $ \ times $ 10 $^{ - 5} $。这些结果证明了拟议的DRF作为非侵入性生物标志物在预测脑肿瘤患者的治疗反应中的有用性。

Parkinson's disease is marked by altered and increased firing characteristics of pathological oscillations in the brain. In other words, it causes abnormal synchronous oscillations and suppression during neurological processing. In order to examine and regulate the synchronization and pathological oscillations in motor circuits, deep brain stimulators (DBS) are used. Although machine learning methods have been applied for the investigation of suppression, these models require large amounts of training data and computational power, both of which pose challenges to resource-constrained DBS. This research proposes a novel reinforcement learning (RL) framework for suppressing the synchronization in neuronal activity during episodes of neurological disorders with less power consumption. The proposed RL algorithm comprises an ensemble of a temporal representation of stimuli and a twin-delayed deep deterministic (TD3) policy gradient algorithm. We quantify the stability of the proposed framework to noise and reduced synchrony using RL for three pathological signaling regimes: regular, chaotic, and bursting, and further eliminate the undesirable oscillations. Furthermore, metrics such as evaluation rewards, energy supplied to the ensemble, and the mean point of convergence were used and compared to other RL algorithms, specifically the Advantage actor critic (A2C), the Actor critic with Kronecker-featured trust region (ACKTR), and the Proximal policy optimization (PPO).

Human activity recognition (HAR) using drone-mounted cameras has attracted considerable interest from the computer vision research community in recent years. A robust and efficient HAR system has a pivotal role in fields like video surveillance, crowd behavior analysis, sports analysis, and human-computer interaction. What makes it challenging are the complex poses, understanding different viewpoints, and the environmental scenarios where the action is taking place. To address such complexities, in this paper, we propose a novel Sparse Weighted Temporal Attention (SWTA) module to utilize sparsely sampled video frames for obtaining global weighted temporal attention. The proposed SWTA is comprised of two parts. First, temporal segment network that sparsely samples a given set of frames. Second, weighted temporal attention, which incorporates a fusion of attention maps derived from optical flow, with raw RGB images. This is followed by a basenet network, which comprises a convolutional neural network (CNN) module along with fully connected layers that provide us with activity recognition. The SWTA network can be used as a plug-in module to the existing deep CNN architectures, for optimizing them to learn temporal information by eliminating the need for a separate temporal stream. It has been evaluated on three publicly available benchmark datasets, namely Okutama, MOD20, and Drone-Action. The proposed model has received an accuracy of 72.76%, 92.56%, and 78.86% on the respective datasets thereby surpassing the previous state-of-the-art performances by a margin of 25.26%, 18.56%, and 2.94%, respectively.

Topological data analysis (TDA) is a branch of computational mathematics, bridging algebraic topology and data science, that provides compact, noise-robust representations of complex structures. Deep neural networks (DNNs) learn millions of parameters associated with a series of transformations defined by the model architecture, resulting in high-dimensional, difficult-to-interpret internal representations of input data. As DNNs become more ubiquitous across multiple sectors of our society, there is increasing recognition that mathematical methods are needed to aid analysts, researchers, and practitioners in understanding and interpreting how these models' internal representations relate to the final classification. In this paper, we apply cutting edge techniques from TDA with the goal of gaining insight into the interpretability of convolutional neural networks used for image classification. We use two common TDA approaches to explore several methods for modeling hidden-layer activations as high-dimensional point clouds, and provide experimental evidence that these point clouds capture valuable structural information about the model's process. First, we demonstrate that a distance metric based on persistent homology can be used to quantify meaningful differences between layers, and we discuss these distances in the broader context of existing representational similarity metrics for neural network interpretability. Second, we show that a mapper graph can provide semantic insight into how these models organize hierarchical class knowledge at each layer. These observations demonstrate that TDA is a useful tool to help deep learning practitioners unlock the hidden structures of their models.

We introduce SketchySGD, a stochastic quasi-Newton method that uses sketching to approximate the curvature of the loss function. Quasi-Newton methods are among the most effective algorithms in traditional optimization, where they converge much faster than first-order methods such as SGD. However, for contemporary deep learning, quasi-Newton methods are considered inferior to first-order methods like SGD and Adam owing to higher per-iteration complexity and fragility due to inexact gradients. SketchySGD circumvents these issues by a novel combination of subsampling, randomized low-rank approximation, and dynamic regularization. In the convex case, we show SketchySGD with a fixed stepsize converges to a small ball around the optimum at a faster rate than SGD for ill-conditioned problems. In the non-convex case, SketchySGD converges linearly under two additional assumptions, interpolation and the Polyak-Lojaciewicz condition, the latter of which holds with high probability for wide neural networks. Numerical experiments on image and tabular data demonstrate the improved reliability and speed of SketchySGD for deep learning, compared to standard optimizers such as SGD and Adam and existing quasi-Newton methods.

深度学习已在许多神经影像应用中有效。但是，在许多情况下，捕获与小血管疾病有关的信息的成像序列的数量不足以支持数据驱动的技术。此外，基于队列的研究可能并不总是具有用于准确病变检测的最佳或必需成像序列。因此，有必要确定哪些成像序列对于准确检测至关重要。在这项研究中，我们旨在找到磁共振成像（MRI）序列的最佳组合，以深入基于学习的肿瘤周围空间（EPV）。为此，我们实施了一个有效的轻巧U-NET，适用于EPVS检测，并全面研究了来自易感加权成像（SWI），流体侵入的反转恢复（FLAIR），T1加权（T1W）和T2的不同信息组合 - 加权（T2W）MRI序列。我们得出的结论是，T2W MRI对于准确的EPV检测最为重要，并且在深神经网络中掺入SWI，FLAIR和T1W MRI可能会使精度的提高无关。

手写的文本识别问题是由计算机视觉社区的研究人员广泛研究的，因为它的改进和适用于日常生活的范围，它是模式识别的子域。自从过去几十年以来，基于神经网络的系统的计算能力提高了计算能力，因此有助于提供最新的手写文本识别器。在同一方向上，我们采用了两个最先进的神经网络系统，并将注意力机制合并在一起。注意技术已被广泛用于神经机器翻译和自动语音识别的领域，现在正在文本识别域中实现。在这项研究中，我们能够在IAM数据集上达到4.15％的字符错误率和9.72％的单词错误率，7.07％的字符错误率和GW数据集的16.14％单词错误率与现有的Flor合并后，GW数据集的单词错误率等。建筑学。为了进一步分析，我们还使用了类似于Shi等人的系统。具有贪婪解码器的神经网络系统，观察到基本模型的字符错误率提高了23.27％。

对比度学习通常用作一种自我监督学习的方法，“锚”和“正”是给定输入图像的两个随机增强，而“负”是所有其他图像的集合。但是，对大批量和记忆库的需求使训练变得困难和缓慢。这促使有监督的对比方法的崛起通过使用带注释的数据来克服这些问题。我们希望通过基于其相似性进行排名，并观察人类偏见（以排名形式）对学习表示的影响，以进一步改善受监督的对比学习。我们认为这是一个重要的问题，因为学习良好的功能嵌入是在计算机视觉中长期以来一直追求的问题。

对比学习通常应用于自学的学习，并且已被证明超过了传统方法，例如三胞胎损失和n对损失。但是，对大批量和记忆库的需求使训练变得困难和缓慢。最近，已经开发出有监督的对比方法来克服这些问题。他们更多地专注于分别或在各个班级之间为每个班级学习一个良好的表示。在这项工作中，我们尝试使用用户定义的排名来基于相似性对类进行排名，以了解所有类之间的有效表示。我们观察到如何将人类偏见纳入学习过程可以改善参数空间中的学习表征。我们表明，我们的结果可与受监督的对比度学习用于图像分类和对象检测，并讨论其在OOD检测中的缺点

草书手写文本识别是模式识别领域中一个具有挑战性的研究问题。当前的最新方法包括基于卷积复发性神经网络和多维长期记忆复发性神经网络技术的模型。这些方法在高度计算上是广泛的模型，在设计级别上也很复杂。在最近的研究中，与基于卷积的复发性神经网络相比，基于卷积神经网络和票面卷积神经网络模型的组合显示出较少的参数。在减少要训练的参数总数的方向上，在这项工作中，我们使用了深度卷积代替标准卷积，结合了封闭式跨跨跨性神经网络和双向封闭式复发单元来减少参数总数接受训练。此外，我们还在测试步骤中包括了基于词典的单词梁搜索解码器。它还有助于提高模型的整体准确性。我们在IAM数据集上获得了3.84％的字符错误率和9.40％的单词错误率；乔治·华盛顿数据集的字符错误率和14.56％的字符错误率和14.56％的单词错误率。