SynthXNet: Adversarial Learning for Data Augmentation in CoVID Severity Classification from X-Rays

Data augmentation has been a prevalent approach in improving the performance of deep learning models against slight variations in data. Adversarial learning is one such form of data augmentation. In this work, we aim to introduce a framework to generate harder examples for a specific object class and an adversarial attack for the object detection task. We have also presented our study on the effect of training against such generated harder examples and adversarial samples in object detection. We have applied this adversarial learning technique to a YOLOv3 model and due to the nature of the attack, we demonstrated a substantial improvement in average precision (AP) for a single class of the COCO dataset. As per the literature, we are the first to introduce this kind of class-specific data augmentation strategy in object detection. With our approach, we have shown an improvement of 23.34% in AP for Cat class and 3.1% on overall mAP of YOLOv3 model on clean validation data, while 43.5% improvement in AP for the Cat class on the composite images with class-specific adversarial samples.

Pathological diagnosis assists in saving human lives, but such models are annotation hungry and pathological images are notably expensive to annotate. Contrastive learning could be a promising solution that relies only on the unlabeled training data to generate informative representations. However, the majority of current methods in contrastive learning have the following two issues: (1) positive samples produced through random augmentation are less challenging, and (2) false negative pairs problem caused by negative sampling bias. To alleviate the above issues, we propose a novel contrastive learning method called Cluster-Aware Adversarial Contrastive Learning (CA2CL). Specifically, a mixed data augmentation technique is provided to learn more transferable representations by generating more discriminative sample pairs. Furthermore, to mitigate the effects of inherent false negative pairs, we adopt a cluster-aware loss to identify similarities between instances and incorporate them into the process of contrastive learning. Finally, we generate challenging contrastive data pairs by adversarial learning, and adversarially learn robust representations in the representation space without the labeled training data, which aims to maximize the similarity between the augmented sample and the related adversarial sample. Our proposed CA2CL is evaluated on two public datasets: NCT-CRC-HE and PCam for the fine-tuning and linear evaluation tasks and on two other public datasets: GlaS and CARG for the detection and segmentation tasks, respectively. Extensive experimental results demonstrate the superior performance improvement of our method over several Self-supervised learning (SSL) methods and ImageNet pretraining particularly in scenarios with limited data availability for all four tasks.

Dysarthria is a neurological speech disorder that affects the speech intelligibility of the speaker. Speech assistive aids are developed to support their communication needs. Successful speech assistive aids are developed using automatic speech recognition systems trained using their own speech data. The effectiveness and usefulness of speech recognition systems depend on the amount of speech data used for training. However, collecting a large amount of dysarthric speech data is difficult. Data augmentation involves applying transformation techniques to increase the quantity of available speech data. Adding noise data is also one of the approaches to make such transformations and create a new volume of data. However, care should be taken while using noise data for the transformation of the dysarthric speech data since dysarthria on its own is disordered data, and adding even more distortion reduces its quality of it. However, by performing a proper analysis of the noisy data, noise can also be used as a source to create new samples of dysarthric speech data. This paper concentrates on identifying noise characteristics and finding the suitability of using noise as a source for data augmentation in dysarthric speech. With the noise-augmented dysarthric speech data, dysarthric speech recognition systems were trained to evaluate the quality of the augmented data. It was noted that for dysarthric speakers, especially with the severe category, the low-frequency noise selection approach has resulted in a lower WER than the without augmentation by 12.29%.

Untargeted white-box adversarial attack with heuristic defence methods in real-time deep learning based network intrusion detection system

Toxic content detection plays a vital role in addressing the misuse of social media platforms to harm people or groups due to their race, gender or ethnicity.However, due to the nature of the datasets, systems develop an unintended bias due to the over-generalization of the model to the training data.This compromises the fairness of the systems, which can impact certain groups due to their race, gender, etc. Existing methods mitigate bias using data augmentation, adversarial learning, etc., which require re-training and adding extra parameters to the model.In this work, we present a robust and generalizable technique BiasWipe to mitigate unintended bias in language models.BiasWipe utilizes model interpretability using Shapley values, which achieve fairness by pruning the neuron weights responsible for unintended bias.It first identifies the neuron weights responsible for unintended bias and then achieves fairness by pruning them without loss of original performance.It does not require re-training or adding extra parameters to the model.To show the effectiveness of our proposed technique for bias unlearning, we perform extensive experiments for Toxic content detection for BERT, RoBERTa, and GPT models. 1 .

With the rise of e-commerce, personalized recommendation algorithms have received much attention in recent years. Meanwhile, multimodal recommendation algorithms have become the next competitive track of personalized recommendation. The current mainstream recommendation algorithms (e.g., NeuMF, NGCF) rely too much on empirical data and do not effectively utilize multimodal information to model user preferences, while there is the problem of sparsity of user preference data. Secondly, they are still limited to using the same weights to fuse the item features of different modalities, and have the problem of inaccurate recommendation. For this reason, this paper proposes Multi-Modal Self-Supervised Learning Algorithm Based Product Recommendation (MMSLRec). (1) Data augmentation by self-supervised adversarial perturbation generation learning is performed to supplement the missing interaction information of tailed products to solve the common data sparsity problem in product recommendation. (2) A multimodal representation learning module is introduced to capture deep features in image and text modalities using AlexNet and Bert, respectively, in order to avoid the recommendation accuracy degradation problem caused by insufficient data feature learning. (3) Learning the user's perceived strength in different modalities, using the user co-occurrence matrix to fuse the features and make recommendations. Experiments on Amazon-Electronics, Amazon-Clothing, and Amazon-Baby, with different degrees of data sparsity verify the effectiveness of our MMSLRec in solving the data sparsity problem and the multimodal user preference modeling problem, and compared to the state-of-the-art baseline recommendation model on the three datasets, the Recall@20 improved by 9.26%, 3.11% and 2.92%, respectively.

Deep neural networks require a large amount of data for supervised training and learning, but it is often difficult to obtain a large amount of label data in practical applications. Since semi-supervised learning can reduce the dependence of deep networks on label data, the generative confrontation network based on semi-supervised learning can improve the classification effect. Although researchers have made progress in semi-supervised learning, small-scale, fully-supervised tasks have not been solved well, because even unlabeled data cannot be obtained in large quantities in such tasks. Therefore, we propose a new GAN model EAC-GAN based on the auxiliary classifier generative adversarial network (ACGAN), which uses genetic algorithms and semi-supervised algorithms to improve classification under fully supervised conditions. Our method utilizes ACGAN to generate artificial data for supplementing supervised classification. More specifically, we attached an external classifier to the original ACGAN generator, so it was named EAC-GAN instead of sharing an architecture with the discriminator. Our experiments show that the performance of EAC-GAN is far superior to standard methods based on data augmentation and regularization, and it is effective on a small amount of real data sets.KeywordsImage synthesisData enhancementGenerative adversarial networkSemi-supervised learning

A survey of recent methods for addressing AI fairness and bias in biomedicine

sTBI-GAN: An adversarial learning approach for data synthesis on traumatic brain segmentation

Boosting robustness of network intrusion detection systems: A novel two phase defense strategy against untargeted white-box optimization adversarial attack

The presence of defects in substation equipment is a major factor affecting the safety of power transmission. Therefore, timely and accurate detection of these defects is crucial. As intelligent inspection robots advance, using mainstream object detection models to diagnose surface defects in substation equipment has become a focal point of current research. However, the lack of defect image data is one of the main factors affecting the accuracy of supervised deep learning-based defect detection models. To address the issue of insufficient training data for defect images with complex backgrounds, such as rust and surface oil leakage in substation equipment, which leads to the poor performance of detection models, this paper proposes a novel adversarial deep learning model for substation defect image generation: the Abnormal Defect Detection Generative Adversarial Network (ADD-GAN). Unlike existing generative adversarial networks, this model generates defect images based on effectively segmented local areas of substation equipment images, avoiding image distortion caused by global style changes. Additionally, the model uses a joint discriminator for both overall images and defect images to address the issue of low attention to local defect areas, thereby reducing the loss of image features. This approach enhances the overall quality of generated images as well as locally generated defect images, ultimately improving image realism. Experimental results demonstrate that the YOLOV7 object detection model trained on the dataset generated using the ADD-GAN method achieves a mean average precision (mAP) of 81.5% on the test dataset, and outperforms other image data augmentation and generation methods. This confirms that the ADD-GAN method can generate a high-fidelity image dataset of substation equipment defects.

Abnormal traffic detection is the core component of the network intrusion detection system. Although semisupervised methods can detect zero-day attack traffic, previous work suffers from high false alarms because the trained model is simply based on normal traffic. In this article, we propose an accurate abnormal traffic detection method using pseudoanomaly, consisting of an efficient feature extraction framework and a novel denoise autoencoder-generative adversarial network (DAE-GAN) model. The feature extraction framework adopts an innovative packet window scheme to extract spatial and temporal features from traffic flows. The DAE-GAN model has multiple DAEs to achieve efficient data augmentation and generate high-quality pseudoanomalies. The pseudoanomalies are obtained by adding noise on normal traffic and enhanced by adversarial learning in DAE-GAN. Our semisupervised detection method, exploiting both normal data and generated pseudoanomalies, achieves a precision of 98.6% on the NSL-KDD dataset and 98.5% on the UNSW-NB15 dataset. Compared with the state-of-the-art, the detection precision and recall under different user behaviors are significantly improved. The evaluation on four attack datasets shows that our method has a high flow-wise precision of over 99% and a high recall of 60.6%.

Real-world entities' behaviors, associated with their side information, are often recorded over time as asynchronous event sequences. Such event sequences are the basis of many practical applications, neural spiking train study, earth quack prediction, crime analysis, infectious disease diffusion forecasting, condition-based preventative maintenance, information retrieval and behavior-based network analysis and services, etc. Temporal point process (TPP) is a principled mathematical tool for the modeling and learning of asynchronous event sequences, which captures the instantaneous happening rate of the events and the temporal dependency between historical and current events. TPP provides us with an interpretable model to describe the generative mechanism of event sequences, which is beneficial for event prediction and causality analysis. Recently, it has been shown that TPP has potentials to many machine learning and data science applications and can be combined with other cutting-edge machine learning techniques like deep learning, reinforcement learning, adversarial learning, and so on. We will start with an elementary introduction of TPP model, including the basic concepts of the model, the simulation method of event sequences; in the second part of the tutorial, we will introduce typical TPP models and their traditional learning methods; in the third part of the tutorial, we will discuss the recent progress on the modeling and learning of TPP, including neural network-based TPP models, generative adversarial networks (GANs) for TPP, and deep reinforcement learning of TPP. We will further talk about the practical application of TPP, including useful data augmentation methods for learning from imperfect observations, typical applications and examples like healthcare and industry maintenance, and existing open source toolboxes.

The pursuit of robust 3D object detection has emerged as a critical focus within the realm of computer vision. This paper presents a curriculum-guided adversarial learning (CGAL) framework, which significantly enhances the adversarial robustness and detection accuracy of the LiDAR-based 3D object detector PointPillars. By employing adversarial learning with prior curriculum expertise, this framework effectively resists adversarial perturbations generated by a novel attack method, P-FGSM, on 3D point clouds. By masterfully constructing a nonlinear enhancement block (NEB) based on the radial basis function network for PointPillars to adapt to the CGAL, a novel 3D object detector named Pillar-RBFN was developed; it exhibits intrinsic adversarial robustness without undergoing adversarial training. In order to tackle the class imbalance issue within the KITTI dataset, a data augmentation technique has been designed that singly samples the point cloud with additional ground truth objects frame by frame (SFGTS), resulting in the creation of an adversarial version of the original KITTI dataset named Adv-KITTI. Moreover, to further alleviate this issue, an adaptive variant of focal loss was formulated, effectively directing the model's attention to challenging objects during the training process. Extensive experiments demonstrate that the proposed CGAL achieves an improvement of 0.8∼2.5 percentage points in mean average precision (mAP) compared to conventional training methods, and the models trained with Adv-KITTI have shown an enhancement of at least 15 percentage points in mAP, compellingly testifying to the effectiveness of our method.

Computer vision systems are popular tools for monitoring tasks in highly specialized production environments. The training and configuration, however, still represents a time-consuming task in process automation. Convolutional neural networks have helped to improve the ability to detect even complex anomalies withouth exactly modeling image filters and segmentation strategies for a wide range of application scenarios. In recent publications, image-to-image translation using generative adversarial networks was introduced as a promising strategy to apply patterns to other domains without prior explicit mapping. We propose a new approach for generating augmented data to enable the training of convolutional neural networks for semantic segmentation with a minimum of real labeled data. We present qualitative results and demonstrate the application of our system on textile images of carbon fibers with structural anomalies. This paper compares the potential of image-to-image translation networks with common data augmentation strategies such as image scaling, rotation or mirroring. We train and test on image data acquired from a high resolution camera within an industrial monitoring use case. The experiments show that our system is comparable to common data augmentation approaches. Our approach extends the toolbox of semantic segmentation since it allows for generating more problem-specific training data from sparse input.