Human Activity Recognition (HAR) is an emerging technology with several applications in surveillance, security, and healthcare sectors. Noninvasive HAR systems based on Wi-Fi Channel State Information (CSI) signals can be developed leveraging the quick growth of ubiquitous Wi-Fi technologies, and the correlation between CSI dynamics and body motions. In this paper, we propose Principal Component-based Wavelet Convolutional Neural Network (or PCWCNN) -- a novel approach that offers robustness and efficiency for practical real-time applications. Our proposed method incorporates two efficient preprocessing algorithms -- the Principal Component Analysis (PCA) and the Discrete Wavelet Transform (DWT). We employ an adaptive activity segmentation algorithm that is accurate and computationally light. Additionally, we used the Wavelet CNN for classification, which is a deep convolutional network analogous to the well-studied ResNet and DenseNet networks. We empirically show that our proposed PCWCNN model performs very well on a real dataset, outperforming existing approaches.

Non-negative matrix factorization is a popular unsupervised machine learning algorithm for extracting meaningful features from data which are inherently non-negative. However, such data sets may often contain privacy-sensitive user data, and therefore, we may need to take necessary steps to ensure the privacy of the users while analyzing the data. In this work, we focus on developing a Non-negative matrix factorization algorithm in the privacy-preserving framework. More specifically, we propose a novel privacy-preserving algorithm for non-negative matrix factorisation capable of operating on private data, while achieving results comparable to those of the non-private algorithm. We design the framework such that one has the control to select the degree of privacy grantee based on the utility gap. We show our proposed framework's performance in six real data sets. The experimental results show that our proposed method can achieve very close performance with the non-private algorithm under some parameter regime, while ensuring strict privacy.

Adversarial attacks hamper the decision-making ability of neural networks by perturbing the input signal. The addition of calculated small distortion to images, for instance, can deceive a well-trained image classification network. In this work, we propose a novel attack technique called Sparse Adversarial and Interpretable Attack Framework (SAIF). Specifically, we design imperceptible attacks that contain low-magnitude perturbations at a small number of pixels and leverage these sparse attacks to reveal the vulnerability of classifiers. We use the Frank-Wolfe (conditional gradient) algorithm to simultaneously optimize the attack perturbations for bounded magnitude and sparsity with $O(1/\sqrt{T})$ convergence. Empirical results show that SAIF computes highly imperceptible and interpretable adversarial examples, and outperforms state-of-the-art sparse attack methods on the ImageNet dataset.

Can we take a recurrent neural network (RNN) trained to translate between languages and augment it to support a new natural language without retraining the model from scratch? Can we fix the faulty behavior of the RNN by replacing portions associated with the faulty behavior? Recent works on decomposing a fully connected neural network (FCNN) and convolutional neural network (CNN) into modules have shown the value of engineering deep models in this manner, which is standard in traditional SE but foreign for deep learning models. However, prior works focus on the image-based multiclass classification problems and cannot be applied to RNN due to (a) different layer structures, (b) loop structures, (c) different types of input-output architectures, and (d) usage of both nonlinear and logistic activation functions. In this work, we propose the first approach to decompose an RNN into modules. We study different types of RNNs, i.e., Vanilla, LSTM, and GRU. Further, we show how such RNN modules can be reused and replaced in various scenarios. We evaluate our approach against 5 canonical datasets (i.e., Math QA, Brown Corpus, Wiki-toxicity, Clinc OOS, and Tatoeba) and 4 model variants for each dataset. We found that decomposing a trained model has a small cost (Accuracy: -0.6%, BLEU score: +0.10%). Also, the decomposed modules can be reused and replaced without needing to retrain.

Recent advances in pixel-level tasks (e.g., segmentation) illustrate the benefit of long-range interactions between aggregated region-based representations that can enhance local features. However, such pixel-to-region associations and the resulting representation, which often take the form of attention, cannot model the underlying semantic structure of the scene (e.g., individual objects and, by extension, their interactions). In this work, we take a step toward addressing this limitation. Specifically, we propose an architecture where we learn to project image features into latent region representations and perform global reasoning across them, using a transformer, to produce contextualized and scene-consistent representations that are then fused with original pixel-level features. Our design enables the latent regions to represent semantically meaningful concepts, by ensuring that activated regions are spatially disjoint and unions of such regions correspond to connected object segments. The resulting semantic global reasoning (SGR) is end-to-end trainable and can be combined with any semantic segmentation framework and backbone. Combining SGR with DeepLabV3 results in a semantic segmentation performance that is competitive to the state-of-the-art, while resulting in more semantically interpretable and diverse region representations, which we show can effectively transfer to detection and instance segmentation. Further, we propose a new metric that allows us to measure the semantics of representations at both the object class and instance level.

We introduce an information-maximization approach for the Generalized Category Discovery (GCD) problem. Specifically, we explore a parametric family of loss functions evaluating the mutual information between the features and the labels, and find automatically the one that maximizes the predictive performances. Furthermore, we introduce the Elbow Maximum Centroid-Shift (EMaCS) technique, which estimates the number of classes in the unlabeled set. We report comprehensive experiments, which show that our mutual information-based approach (MIB) is both versatile and highly competitive under various GCD scenarios. The gap between the proposed approach and the existing methods is significant, more so when dealing with fine-grained classification problems. Our code: \url{https://github.com/fchiaroni/Mutual-Information-Based-GCD}.

Data-driven modeling approaches such as jump tables are promising techniques to model populations of resistive random-access memory (ReRAM) or other emerging memory devices for hardware neural network simulations. As these tables rely on data interpolation, this work explores the open questions about their fidelity in relation to the stochastic device behavior they model. We study how various jump table device models impact the attained network performance estimates, a concept we define as modeling bias. Two methods of jump table device modeling, binning and Optuna-optimized binning, are explored using synthetic data with known distributions for benchmarking purposes, as well as experimental data obtained from TiOx ReRAM devices. Results on a multi-layer perceptron trained on MNIST show that device models based on binning can behave unpredictably particularly at low number of points in the device dataset, sometimes over-promising, sometimes under-promising target network accuracy. This paper also proposes device level metrics that indicate similar trends with the modeling bias metric at the network level. The proposed approach opens the possibility for future investigations into statistical device models with better performance, as well as experimentally verified modeling bias in different in-memory computing and neural network architectures.

作物疾病是对粮食安全的主要威胁，其快速识别对于防止产量损失很重要。由于缺乏必要的基础设施，因此很难迅速识别这些疾病。计算机视觉的最新进展和智能手机渗透的渗透为智能手机辅助疾病识别铺平了道路。大多数植物疾病在植物的叶面结构上留下了特定的文物。这项研究于2020年在巴基斯坦拉合尔工程技术大学计算机科学与工程系进行，以检查基于叶片的植物疾病识别。这项研究为叶面疾病鉴定提供了基于神经网络的深度解决方案，并纳入了图像质量评估，以选择执行识别所需质量的图像，并将其命名为农业病理学家（AGRO PATH）。新手摄影师的捕获图像可能包含噪音，缺乏结构和模糊，从而导致诊断失败或不准确。此外，Agropath模型具有99.42％的叶面疾病鉴定精度。拟议的添加对于在农业领域的叶面疾病鉴定的应用特别有用。

本文展示了一种新的方法，可以使用语义分段特征提高面部识别姿势不变。拟议的SEG-DISTILD-ID网络共同学习识别和语义分割任务，然后将分割任务“蒸馏”（Mobilenet编码器）。在强调头置变化的公开数据集中，针对三个最先进的编码器进行了基准测试。实验评估表明，SEG-DISTILD-ID网络显示出显着的鲁棒性优势，相比之下，RESNET-101的测试准确性达到99.9％，VGG-19的96.1％，IntectionV3的vgg-19和96.3％。这是使用顶部编码器推理参数的大约十分之一来实现的。这些结果表明，蒸馏的语义分割特征可以有效地解决面部识别姿势不变。

背景：基于AI的足够大型，精心策划的医疗数据集的分析已被证明有望提供早期检测，更快的诊断，更好的决策和更有效的治疗方法。但是，从多种来源获得的如此高度机密且非常敏感的医疗数据通常受到高度限制，因为不当使用，不安全的存储，数据泄漏或滥用可能侵犯了一个人的隐私。在这项工作中，我们将联合学习范式应用于异质的，孤立的高清心电图集，该图从12铅的ECG传感器阵列到达来训练AI模型。与在中心位置收集相同的数据时，我们评估了所得模型的能力，与经过训练的最新模型相比，获得了等效性能。方法：我们提出了一种基于联合学习范式训练AI模型的隐私方法，以培训AI模型，以实现异质，分布式，数据集。该方法应用于基于梯度增强，卷积神经网络和具有长期短期记忆的复发神经网络的广泛机器学习技术。这些模型在一个心电图数据集上进行了培训，该数据集包含从六名地理分开和异质来源的43,059名患者收集的12个铅录音。研究结果：用于检测心血管异常的AI模型的结果集获得了与使用集中学习方法训练的模型相当的预测性能。解释：计算参数的方法在本地为全局模型做出了贡献，然后仅交换此类参数，而不是ML中的整个敏感数据，这有助于保留医疗数据隐私。