背景和目的：与生物医学分析相结合的人工智能（AI）方法在Pandemics期间具有关键作用，因为它有助于释放来自医疗保健系统和医生的压力压力。由于持续的Covid-19危机在具有茂密的人口和巴西和印度等测试套件中的国家恶化，放射性成像可以作为准确分类Covid-19患者的重要诊断工具，并在适当时期规定必要的治疗。通过这种动机，我们基于使用胸部X射线检测Covid-19感染肺的深度学习架构的研究。数据集：我们共收集了三种不同类标签的2470张图片，即健康的肺，普通肺炎和Covid-19感染的肺炎，其中470个X射线图像属于Covid-19类。方法：我们首先使用直方图均衡技术预处理所有图像，并使用U-Net架构进行它们。然后，VGG-16网络用于从预处理图像中的特征提取，该特征提取通过SMTE过采样技术进一步采样以实现平衡数据集。最后，使用具有10倍交叉验证的支持向量机（SVM）分类器分类类平衡功能，评估精度。结果和结论：我们的新方法结合了众所周知的预处理技术，特征提取方法和数据集平衡方法，使我们在2470 X射线图像的数据集中获得了Covid-19图像的优秀识别率为98％ 。因此，我们的模型适用于用于筛选目的的医疗保健设施。

Research has shown that climate change creates warmer temperatures and drier conditions, leading to longer wildfire seasons and increased wildfire risks in the United States. These factors have in turn led to increases in the frequency, extent, and severity of wildfires in recent years. Given the danger posed by wildland fires to people, property, wildlife, and the environment, there is an urgency to provide tools for effective wildfire management. Early detection of wildfires is essential to minimizing potentially catastrophic destruction. In this paper, we present our work on integrating multiple data sources in SmokeyNet, a deep learning model using spatio-temporal information to detect smoke from wildland fires. Camera image data is integrated with weather sensor measurements and processed by SmokeyNet to create a multimodal wildland fire smoke detection system. We present our results comparing performance in terms of both accuracy and time-to-detection for multimodal data vs. a single data source. With a time-to-detection of only a few minutes, SmokeyNet can serve as an automated early notification system, providing a useful tool in the fight against destructive wildfires.

With large-scale adaption to biometric based applications, security and privacy of biometrics is utmost important especially when operating in unsupervised online mode. This work proposes a novel approach for generating new artificial fingerprints also called proxy fingerprints that are natural looking, non-invertible, revocable and privacy preserving. These proxy biometrics can be generated from original ones only with the help of a user-specific key. Instead of using the original fingerprint, these proxy templates can be used anywhere with same convenience. The manuscripts walks through an interesting way in which proxy fingerprints of different types can be generated and how they can be combined with use-specific keys to provide revocability and cancelability in case of compromise. Using the proposed approach a proxy dataset is generated from samples belonging to Anguli fingerprint database. Matching experiments were performed on the new set which is 5 times larger than the original, and it was found that their performance is at par with 0 FAR and 0 FRR in the stolen key, safe key scenarios. Other parameters on revocability and diversity are also analyzed for protection performance.

Recently, online social media has become a primary source for new information and misinformation or rumours. In the absence of an automatic rumour detection system the propagation of rumours has increased manifold leading to serious societal damages. In this work, we propose a novel method for building automatic rumour detection system by focusing on oversampling to alleviating the fundamental challenges of class imbalance in rumour detection task. Our oversampling method relies on contextualised data augmentation to generate synthetic samples for underrepresented classes in the dataset. The key idea exploits selection of tweets in a thread for augmentation which can be achieved by introducing a non-random selection criteria to focus the augmentation process on relevant tweets. Furthermore, we propose two graph neural networks(GNN) to model non-linear conversations on a thread. To enhance the tweet representations in our method we employed a custom feature selection technique based on state-of-the-art BERTweet model. Experiments of three publicly available datasets confirm that 1) our GNN models outperform the the current state-of-the-art classifiers by more than 20%(F1-score); 2) our oversampling technique increases the model performance by more than 9%;(F1-score) 3) focusing on relevant tweets for data augmentation via non-random selection criteria can further improve the results; and 4) our method has superior capabilities to detect rumours at very early stage.

A number of competing hypotheses have been proposed to explain why small-batch Stochastic Gradient Descent (SGD)leads to improved generalization over the full-batch regime, with recent work crediting the implicit regularization of various quantities throughout training. However, to date, empirical evidence assessing the explanatory power of these hypotheses is lacking. In this paper, we conduct an extensive empirical evaluation, focusing on the ability of various theorized mechanisms to close the small-to-large batch generalization gap. Additionally, we characterize how the quantities that SGD has been claimed to (implicitly) regularize change over the course of training. By using micro-batches, i.e. disjoint smaller subsets of each mini-batch, we empirically show that explicitly penalizing the gradient norm or the Fisher Information Matrix trace, averaged over micro-batches, in the large-batch regime recovers small-batch SGD generalization, whereas Jacobian-based regularizations fail to do so. This generalization performance is shown to often be correlated with how well the regularized model's gradient norms resemble those of small-batch SGD. We additionally show that this behavior breaks down as the micro-batch size approaches the batch size. Finally, we note that in this line of inquiry, positive experimental findings on CIFAR10 are often reversed on other datasets like CIFAR100, highlighting the need to test hypotheses on a wider collection of datasets.

The compute-intensive nature of neural networks (NNs) limits their deployment in resource-constrained environments such as cell phones, drones, autonomous robots, etc. Hence, developing robust sparse models fit for safety-critical applications has been an issue of longstanding interest. Though adversarial training with model sparsification has been combined to attain the goal, conventional adversarial training approaches provide no formal guarantee that the models would be robust against any rogue samples in a restricted space around a benign sample. Recently proposed verified local robustness techniques provide such a guarantee. This is the first paper that combines the ideas from verified local robustness and dynamic sparse training to develop `SparseVLR'-- a novel framework to search verified locally robust sparse networks. Obtained sparse models exhibit accuracy and robustness comparable to their dense counterparts at sparsity as high as 99%. Furthermore, unlike most conventional sparsification techniques, SparseVLR does not require a pre-trained dense model, reducing the training time by 50%. We exhaustively investigated SparseVLR's efficacy and generalizability by evaluating various benchmark and application-specific datasets across several models.

In many real-world problems, the learning agent needs to learn a problem's abstractions and solution simultaneously. However, most such abstractions need to be designed and refined by hand for different problems and domains of application. This paper presents a novel top-down approach for constructing state abstractions while carrying out reinforcement learning. Starting with state variables and a simulator, it presents a novel domain-independent approach for dynamically computing an abstraction based on the dispersion of Q-values in abstract states as the agent continues acting and learning. Extensive empirical evaluation on multiple domains and problems shows that this approach automatically learns abstractions that are finely-tuned to the problem, yield powerful sample efficiency, and result in the RL agent significantly outperforming existing approaches.

医疗保健是人类生活的重要方面。大流行后，在医疗保健中使用技术的流形增加了。文献中提出的基于物联网的系统和设备可以帮助老年人，儿童和成人面临/经历健康问题。本文详尽地回顾了39个基于可穿戴的数据集，这些数据集可用于评估系统以识别日常生活和跌倒活动。使用五种机器学习方法，即逻辑回归，线性判别分析，K-Nearest邻居，决策树和幼稚的贝叶斯对SIFFALL数据集进行比较分析。数据集以两种方式进行修改，首先使用数据集中存在的所有属性，并以二进制形式标记。第二，计算三个轴（x，y，z）的三个轴（x，y，z）的幅度，然后计算出用于标签属性的实验。实验是对一个受试者，十个受试者和所有受试者进行的，并在准确性，精度和召回方面进行比较。从这项研究中获得的结果证明，KNN在准确性，精度和召回方面胜过其他机器学习方法。还可以得出结论，数据个性化提高了准确性。

老年人的跌倒检测是一些经过深入研究的问题，其中包括多种拟议的解决方案，包括可穿戴和不可磨损的技术。尽管现有技术的检测率很高，但由于需要佩戴设备和用户隐私问题，因此缺乏目标人群的采用。我们的论文提供了一种新颖的，不可磨损的，不受欢迎的和可扩展的解决方案，用于秋季检测，该解决方案部署在配备麦克风的自主移动机器人上。所提出的方法使用人们在房屋中记录的环境声音输入。我们专门针对浴室环境，因为它很容易跌落，并且在不危害用户隐私的情况下无法部署现有技术。目前的工作开发了一种基于变压器体系结构的解决方案，该解决方案从浴室中获取嘈杂的声音输入，并将其分为秋季/禁止类别，准确性为0.8673。此外，提出的方法可扩展到其他室内环境，除了浴室外，还适合在老年家庭，医院和康复设施中部署，而无需用户佩戴任何设备或不断受到传感器的“观察”。

大型基于变压器的预训练的语言模型在各种知识密集的任务上取得了令人印象深刻的表现，并可以在其参数中捕获事实知识。我们认为，考虑到不断增长的知识和资源需求，在模型参数中存储大量知识是亚最佳选择。我们认为，更有效的替代方法是向模型提供对上下文相关的结构化知识的明确访问，并训练它以使用该知识。我们提出了LM核 - 实现这一目标的一般框架 - 允许从外部知识源对语言模型培训的\ textit {解耦}，并允许后者更新而不会影响已经训练的模型。实验结果表明，LM核心获得外部知识，在知识探索任务上的最先进的知识增强语言模型中实现了重要而强大的优于性能。可以有效处理知识更新；并在两个下游任务上表现良好。我们还提出了一个彻底的错误分析，突出了LM核的成功和失败。