Supervised Hyperspectral Remote Sensing Image Classification Using Graph Attention Networks with Hybrid Pooling

<strong class="journal-contentHeaderColor">Abstract.</strong> Hyperspectral images contain abundant spectral and spatial information about the earth's surface, labeling data processing and analysis more difficult, as well as the problem of sample labeling. In this paper, local binary pattern (LBP), sparse representation and mixed logistic regression model are introduced, and a sample labeling method based on neighborhood information and priority classifier discrimination is presented. Then, a hyperspectral remote sensing image classification method based on texture features and semi-supervised learning is implemented. The LBP is employed to extract features of spatial texture information from remote sensing images and enrich the feature information of samples. Then the multivariate logistic regression model is used to select the unlabeled samples with the largest amount of information, and the unlabeled samples with neighborhood information and priority classifier tags are selected to obtain the pseudo-labeled samples after learning. By making full use of the advantages of sparse representation and mixed logistic regression model, a new hyperspectral remote sensing image classification model based on semi-supervised learning is constructed to effectively achieve accurate classification of hyperspectral images. The data of Indian Pines, Salinas scene and Pavia University are selected to verify the validity of the proposed method. The experiment results show that the proposed classification method can obtain higher classification accuracy and show stronger timeliness and generalization ability.

The n-octanol/buffer solution distribution coefficient at pH = 7.4 (log D7.4) is an indicator of lipophilicity, and it influences a wide variety of absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties and druggability of compounds. In log D7.4 prediction, graph neural networks (GNNs) can uncover subtle structure-property relationships (SPRs) by automatically extracting features from molecular graphs that facilitate the learning of SPRs, but their performances are often limited by the small size of available datasets. Herein, we present a transfer learning strategy called pretraining on computational data and then fine-tuning on experimental data (PCFE) to fully exploit the predictive potential of GNNs. PCFE works by pretraining a GNN model on 1.71 million computational log D data (low-fidelity data) and then fine-tuning it on 19,155 experimental log D7.4 data (high-fidelity data). The experiments for three GNN architectures (graph convolutional network (GCN), graph attention network (GAT), and Attentive FP) demonstrated the effectiveness of PCFE in improving GNNs for log D7.4 predictions. Moreover, the optimal PCFE-trained GNN model (cx-Attentive FP, Rtest2 = 0.909) outperformed four excellent descriptor-based models (random forest (RF), gradient boosting (GB), support vector machine (SVM), and extreme gradient boosting (XGBoost)). The robustness of the cx-Attentive FP model was also confirmed by evaluating the models with different training data sizes and dataset splitting strategies. Therefore, we developed a webserver and defined the applicability domain for this model. The webserver (http://tools.scbdd.com/chemlogd/) provides free log D7.4 prediction services. In addition, the important descriptors for log D7.4 were detected by the Shapley additive explanations (SHAP) method, and the most relevant substructures of log D7.4 were identified by the attention mechanism. Finally, the matched molecular pair analysis (MMPA) was performed to summarize the contributions of common chemical substituents to log D7.4, including a variety of hydrocarbon groups, halogen groups, heteroatoms, and polar groups. In conclusion, we believe that the cx-Attentive FP model can serve as a reliable tool to predict log D7.4 and hope that pretraining on low-fidelity data can help GNNs make accurate predictions of other endpoints in drug discovery.

Graph Neural Networks (GNNs) are deep learning models specifically designed for analyzing graph-structured data, capturing complex relationships and structures to improve analysis and prediction. A common task in GNNs is node classification, where each node in the graph is assigned a predefined category. The Graph Attention Network (GAT) is a popular variant of GNNs known for its ability to capture complex dependencies by assigning importance weights to nodes during information aggregation. However, the GAT’s reliance on local attention mechanisms limits its effectiveness in capturing global information and long-range dependencies. To address this limitation, we propose a new attention mechanism called Global-Local Graph Attention (GLGA). Our mechanism enables the GAT to capture long-range dependencies and global graph structures while maintaining its ability to focus on local interactions. We evaluate our algorithm on three citation datasets (Cora, Citeseer, and Pubmed) using multiple metrics, demonstrating its superiority over other baseline models. The proposed GLGA mechanism has been proven to be an effective solution for improving node classification tasks.

Recommendation systems is the core of most online experiences, guiding people to the right products, films, music, courses, and even social links when the choices are overwhelming. They work by learning from large interaction logs and applying predictive models to surface content that fits each user’s tastes, steadily improving as algorithms and data grow richer. As AI and deep learning have developed, classic strategies like collaborative filtering and content-based filtering are increasingly paired with, or superseded by, neural architectures that can model more nuanced patterns in behaviour and content. Among these neural approaches, graph neural networks—and especially Graph Attention Networks (GATs)—have become influential for recommendation because they treat users and items as nodes in a graph and learn from the connections between them. With attention mechanisms, GATs decide which neighbours matter most for a given prediction, amplifying useful signals and dampening noise to learn stronger user and item representations. This survey traces how the industry moved from traditional methods to graph-based models centred on GATs, comparing approaches on scalability, ranking accuracy, data sparsity, and interpretability across widely used benchmarks. Drawing from recent peer‑reviewed work, it highlights architectures and training practices that consistently help in real-world settings, as well as gaps that still limit robust deployment at scale. Looking forward, several directions stand out: using explainable AI to clarify why specific items are recommended, combining reinforcement learning with GATs for adaptive policies, and adopting federated learning to protect user privacy while training on distributed data. The versatility of GAT-based recommenders is already visible across domains—from e‑commerce and online learning to healthcare and social feeds—where graph structure and selective attention naturally fit the data. Overall, the evidence points to GATs as a key ingredient for the next generation of personalized, context‑aware, and trustworthy recommendation systems. Keywords: Recommendation Systems, Collaborative Filtering, Graph Neural Networks, Graph Attention Networks

Graph Neural Networks (GNNs) are deep learning methods which provide the current state of the art performance in node classification tasks. GNNs often assume homophily – neighboring nodes having similar features and labels–, and therefore may not be at their full potential when dealing with non-homophilic graphs. In this work, we focus on addressing this limitation and enable Graph Attention Networks (GAT), a commonly used variant of GNNs, to explore the structural information within each graph locality. Inspired by the positional encoding in the Transformers, we propose a framework, termed Graph Attentional Networks with Positional Embeddings (GAT-POS), to enhance GATs with positional embeddings which capture structural and positional information of the nodes in the graph. In this framework, the positional embeddings are learned by a model predictive of the graph context, plugged into an enhanced GAT architecture, which is able to leverage both the positional and content information of each node. The model is trained jointly to optimize for the task of node classification as well as the task of predicting graph context. Experimental results show that GAT-POS reaches remarkable improvement compared to strong GNN baselines and recent structural embedding enhanced GNNs on non-homophilic graphs.

Edge features contain important information about graphs. However, current state-of-the-art neural network models designed for graph learning, e.g. graph convolutional networks (GCN) and graph attention networks (GAT), adequately utilize edge features, especially multi-dimensional edge features. In this paper, we build a new framework for a family of new graph neural network models that can more sufficiently exploit edge features, including those of undirected or multi-dimensional edges. The proposed framework can consolidate current graph neural network models; e.g. graph convolutional networks (GCN) and graph attention networks (GAT). The proposed framework and new models have the following novelties: First, we propose to use doubly stochastic normalization of graph edge features instead of the commonly used row or symmetric normalization approches used in current graph neural networks. Second, we construct new formulas for the operations in each individual layer so that they can handle multi-dimensional edge features. Third, for the proposed new framework, edge features are adaptive across network layers. As a result, our proposed new framework and new models can exploit a rich source of graph information. We apply our new models to graph node classification on several citation networks, whole graph classification, and regression on several molecular datasets. Compared with the current state-of-the-art methods, i.e. GCNs and GAT, our models obtain better performance, which testify to the importance of exploiting edge features in graph neural networks.

LightGCAN: A lightweight graph convolutional attention network for user preference modeling and personalized recommendation

<title>Abstract</title> Rational vaccine design against emerging and understudied pathogens is hindered by incomplete protein–protein interaction (PPI) maps and limited integration of computational prioritization with network-based inference. Here, we present a unified framework that couples Biomni, a biomedical AI agent providing vaccine-priority and virulence-aware annotations, with graph neural network (GNN) based link prediction on STRING-derived PPIs to systematically identify candidate vaccine targets in Flavobacterium. Starting from the complete Flavobacterium proteome, Biomni-derived antigenicity, subcellular, and virulence features were integrated with high-confidence STRING associations into a unified PPI graph in which isolated and weakly connected proteins were explicitly retained. We evaluated three representative GNN architectures Graph Convolutional Network (GCN), Graph Attention Network (GAT), and GraphSAGE under a consistent three-fold cross-validation scheme and performed priorityaware assessment of predicted high-confidence links (posterior probability ≥ 0.90). GraphSAGE achieved the highest best-fold ROC-AUC (0.5585), followed by GAT (0.5536) and GCN (0.5000), reflecting modest yet meaningful discriminative performance in this sparse, single-species setting. Class-pair analyses revealed that GCN predominantly reconstructed links among lower-priority nodes, while GAT modestly increased coverage of interactions involving High-priority proteins but 1 remained biased toward low-tier combinations. In contrast, GraphSAGE produced a more balanced distribution of predicted links across Biomni priority tiers, including enriched High–Medium and High–Low connections, indicating more effective use of antigenicity and virulence features for inductive generalization to under-characterized proteins. Collectively, these results demonstrate that integrating AI-driven prioritization with inductive GNNs enables biologically informed exploration of missing PPIs and highlights previously overlooked Flavobacterium proteins as plausible vaccine candidates. The proposed Biomni–STRING–GNN framework is modular and transferable, offering a principled template for priority-aware, network-based vaccine target discovery in data-sparse pathogen systems.

Technology CAD (TCAD) tools are pivotal for transistor modeling, enabling physics-based simulations with high accuracy essential for developing next-generation technology nodes. However, their high computational cost and low throughput severely constrain large-scale design-space exploration. Accelerating TCAD simulations while preserving physical accuracy has therefore become a central research objective. A promising approach involves the use of graph-based representations of TCAD meshes fed into graph neural networks (GNNs), which offer rapid and accurate alternatives. However, traditional GNNs, such as Graph Convolutional Networks (GCNs) and Graph Attention Networks (GATs) often falter with noisy transistor-mesh graphs, where embeddings become cluttered and complex. In thiswork, we propose a self-supervisedGNNframework for TCAD device modeling, specifically employing the Self-Supervised GAT (SuperGAT).We demonstrate that self-supervised GNN models, in contrast to GCNs and GATs, introduces a self-supervised edge-prediction task to distinguish informative from redundant topological connections. Our evaluation compares various GNN aggregation schemes demonstrates that SuperGAT successfully reproduces key transistor transfer characteristics drain current–gate voltage (Id–Vg) curves, subthreshold swing (SS) and threshold voltage (Vth). The dataset was generated using 14nm FDSOI transistors. Our SuperGAT model achieves a minimum <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</i><sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> score of 0.992 across all characteristics and an inference time of only 0.007 134 sec per transistor, resulting in a speed-up exceeding 100 000 x compared to TCAD simulation, which underscore the capability to substantially accelerate TCAD transistor simulations in advanced technology development.

With the development of remote sensing technology and machine learning, the research on hyperspectral remote sensing image classification has also progressed rapidly. In this paper, based on the random forest model, a new classification model of hyperspectral remote sensing images is proposed, which can effectively classify the spectral information and texture information of hyperspectral images. First, the texture features are extracted from the hyperspectral remote sensing image data and superimposed on the original spectral domain data, thus forming a new spectral-space domain data. Then, the model forms an optimal combination of parameters by selecting parameters such as the number of decision trees, maximum depth and minimum number of leaves, and this model has a higher classification accuracy for the dataset than the original random forest model. Experimental results on Indian, KSC and Salinas hyperspectral images show that the method proposed in this paper can solve the problems of hyperspectral data nonlinearity and information redundancy due to the expansion of data and the selection of parameter combinations, thus improving the classification effect of the original random forest and the average accuracy of the classification.

With the growing demand for better performance of remote sensing (RS) image classification, a variety of methods have been proposed in RS image classification field in recent years. In general, there are two categories of RS image classification methods: pixel-based (PB) approach and object-based (OB) approach. In this paper, RS image classification methods are reviewed from the perspective of PB approach and OB approach and, specifically, the development and characteristics of a promising methodology for RS image classification named support vector machine (SVM) are surveyed. SVM is particularly popular in the RS field since it can deal with small-sized training dataset and provide higher classification accuracy than some traditional methods like maximum likelihood classifier. Besides, SVM has advantages of high memory-efficiency and strong generalization. However, SVM-based approaches also suffer from some problems. For instance, SVM-based methods tend to overfit due to inappropriate choice of kernel functions and it is inefficient for them to determine the optimum kernel function parameters as well as to process hyperspectral images. This paper also proposes the improvement of SVM-based methods aiming to address the limitations and improve the performance of SVM in RS image classification field. Moreover, future directions for SVM in RS image classification field are presented, expecting to help researchers to find possible research focuses in the future.

Graph neural network has excellent performance in obtaining the similarity relationship of samples, so it has been widely used in computer vision. But hyperspectral remote sensing image (HSI) has some problems such as data redundancy, noise, lack of labeled samples, and insufficient utilization of spatial information. These problems affect the accuracy of HSI classification using graph neural networks. To solve the above problems, this paper proposes graph-based semi-supervised learning with weighted features for HSI classification. The method proposed in this paper first uses the stacked autoencoder network to extract features, which is used to remove the redundancy of HSI data. Then, the similarity attenuation coefficient is introduced to improve the original feature weighting scheme. In this way, the contribution difference of adjacent pixels to the center pixel is reflected. Finally, to obtain more generalized spectral features, a shallow feature extraction mechanism is added to the stacked autoencoder network. And features that have good generalization can solve the problem of the lack of labeled samples. The experiment on three different types of datasets demonstrates that the proposed method in this paper can get better classification performance in the case of the scarcity of labeled samples than other classification methods.

Graph neural networks (GNNs) is an information - processing system that uses message passing among graph nodes. In recent years, GNN variants including graph attention network (GAT), graph convolutional network (GCN), and graph recurrent network (GRN) have shown revolutionary performance in computer vision applications using deep learning and artificial intelligence. These neural network model extensions, collect information in the form of graphs. GNN may be divided into three groups based on the challenges it solves: link prediction, node classification, graph classification. Machines can differentiate and recognise objects in image and video using standard CNNs. Extensive amount of research work needs to be done before robots can have same visual intuition as humans. GNN architectures, on the other hand, may be used to solve various image categorization and video challenges. The number of GNN applications in computer vision not limited, continues to expand. Human-object interaction, actin understanding, image categorization from a few shots and many more. In this paper use of GNN in image and video understanding, design aspects, architecture, applications and implementation challenges towards computer vision is described. GNN is a strong tool for analysing graph data and is still a relatively active area that needs further researches attention to solve many computer vision applications.

AI-Driven molecule generation and bioactivity prediction: A multi-model approach combining VAE, graph and language-based neural networks.

Graph-CAT: Graph Co-Attention Networks via local and global attribute augmentations