Routing, Channel, Key-Rate, and Time-Slot Assignment for QKD in Optical Networks

Abstract: Quantum Key Distribution (QKD) is currently being explored as a solution to the threats posed to current cryptographic protocols by the evolution of quantum computers and algorithms.However, single-photon quantum signals used for QKD permit to achieve key rates strongly limited by link performance (e.g., loss and noise) and propagation distance, especially in multinode QKD networks, making it necessary to design a scheme to efficiently and timely distribute keys to the various nodes.In this work, we introduce the new problem of joint Routing, Channel, Key-rate and Time-slot Assignment (RCKTA), which is addressed with four different network settings, i.e., allowing or not the use of optical bypass (OB) and trusted relay (TR).We first prove the NP-hardness of the RCKTA problem for all network settings and formulate it using a Mixed Integer Linear Programming (MILP) model that combines both quantum channels and quantum key pool (QKP) to provide an optimized solution in terms of number of accepted key rate requests and key storing rate.To deal with problem complexity, we also propose a heuristic algorithm based on an auxiliary graph, and show that it is able to obtain nearoptimal solutions in polynomial time.Results show that allowing OB and TR achieves an acceptance ratio of 39% and 14% higher than that of OB and TR, respectively.Remarkably, these acceptance ratios are obtained with up to 46% less QKD modules (transceivers) compared to TR and only few (less than 1 per path) additional QKD modules than OB.


Generative adversarial nets for unsupervised outlier detection

Abstract: Outlier detection, also known as anomaly detection, has been a persistent and active research area for decades due to its wide range of applications in various fields. Many well-established methods have difficulty fitting the distribution of high-dimensional and complex data, making it difficult to detect outliers that have a low degree of deviation. To address this problem, we combine the distribution fitting capability of generative adversarial nets (GANs) with the specificity of the outlier detection problem and propose a GAN-based unsupervised outlier detection (GUOD) method. In a real dataset mixed with normal objects and outliers, the generator of GANs prefers to fit the distribution of the majority of normal objects to minimize the error; as a result, the generated fake data can be used as an augmentation of normal objects. Next, fake "normal objects" are used to train the autoencoder. Finally, the real data are fed into the autoencoder for one forward propagation, and the reconstruction error of the object is used as its own outlier factor. The top-n objects with the largest reconstruction errors are considered outliers. Extensive experiments are conducted on eight real-world datasets, and the results show that the GUOD method performs better than ten other state-of-the-art algorithms.


Preserving Privacy and Security in Federated Learning

Abstract: Federated learning is known to be vulnerable to both security and privacy issues. Existing research has focused either on preventing poisoning attacks from users or on concealing the local model updates from the server, but not both. However, integrating these two lines of research remains a crucial challenge since they often conflict with one another with respect to the threat model. In this work, we develop a principle framework that offers both privacy guarantees for users and detection against poisoning attacks from them. With a new threat model that includes both an honest-but-curious server and malicious users, we first propose a secure aggregation protocol using homomorphic encryption for the server to combine local model updates in a private manner. Then, a zero-knowledge proof protocol is leveraged to shift the task of detecting attacks in the local models from the server to the users. The key observation here is that the server no longer needs access to the local models for attack detection. Therefore, our framework enables the central server to identify poisoned model updates without violating the privacy guarantees of secure aggregation.


A Q-learning based multi-strategy integrated artificial bee colony algorithm with application in unmanned vehicle path planning

Abstract: Artificial bee colony (ABC) is a prominent algorithm that offers great exploration capabilities among various meta-heuristic algorithms. However, its monotonous and one-dimensional search strategy limits its searching performance in the solving process. Thus, to address this issue, a Q-learning based multi-strategy integrated ABC algorithm (QMABC) is proposed. In the QMABC, multiple search strategies are proposed to utilize different individual experiences and search approaches for solution updates. Then, Q-learning is employed for strategy selection. In comparison to previous studies, this paper introduces more effective state and action configurations within the framework of Q-learning. To evaluate the performance of the QMABC, CEC 2017 benchmark functions are adopted to compare it to different meta-heuristic algorithms including ABC based and non-ABC based algorithms. Moreover, applications in path planning are implemented to further verify the effectiveness of the QMABC. Overall, it should be highlighted that the proposed QMABC demonstrates superiority in both numerical and practical experiments.


Large Separable Kernel Attention: Rethinking the Large Kernel Attention design in CNN

Abstract: Visual Attention Networks (VAN) with Large Kernel Attention (LKA) modules have been shown to provide remarkable performance, that surpasses Vision Transformers (ViTs), on a range of vision-based tasks. However, the depth-wise convolutional layer in these LKA modules incurs a quadratic increase in the computational and memory footprints with increasing convolutional kernel size. To mitigate these problems and to enable the use of extremely large convolutional kernels in the attention modules of VAN, we propose a family of Large Separable Kernel Attention modules, termed LSKA. LSKA decomposes the 2D convolutional kernel of the depth-wise convolutional layer into cascaded horizontal and vertical 1-D kernels. In contrast to the standard LKA design, the proposed decomposition enables the direct use of the depth-wise convolutional layer with large kernels in the attention module, without requiring any extra blocks. We demonstrate that the proposed LSKA module in VAN can achieve comparable performance with the standard LKA module and incur lower computational complexity and memory footprints. We also find that the proposed LSKA design biases the VAN more toward the shape of the object than the texture with increasing kernel size. Additionally, we benchmark the robustness of the LKA and LSKA in VAN, ViTs, and the recent ConvNeXt on the five corrupted versions of the ImageNet dataset that are largely unexplored in the previous works. Our extensive experimental results show that the proposed LSKA module in VAN provides a significant reduction in computational complexity and memory footprints with increasing kernel size while outperforming ViTs, ConvNeXt, and providing similar performance compared to the LKA module in VAN on object recognition, object detection, semantic segmentation, and robustness tests.


Stain normalization methods for histopathology image analysis: A comprehensive review and experimental comparison

Abstract: The advent of whole slide imaging has brought advanced computer-aided diagnosis via medical imaging and artificial intelligence technologies in digital pathology. The examination of tissue samples through whole slide imaging is commonly used to diagnose cancerous diseases, but the analysis of histopathology images through a decision support system is not always accurate due to variations in color caused by different scanning equipment, staining methods, and tissue reactivity. These variabilities decrease the accuracy of computer-aided diagnosis and affect the diagnosis of pathologists. In this context, an effective stain normalization method has proved as a powerful tool to standardize different color appearances and minimize color variations in histopathology images. This study reviews different stain normalization methods highlighting the main methodologies, contributions, advantages, and limitations of correlated works. The state-of-the-art methods are grouped into four distinct categories. Next, we select ten representative methods from the groups and conduct an experimental comparison to investigate the strengths and weaknesses of different methods and rank them according to selected performance accuracy measures. The quality performances of selected methods are compared in terms of quaternion structure similarity index metric, structural similarity index metric, and pearson correlation coefficient conducting experiments on three histopathology datasets. Our findings conclude that the structure-preserving unified transformation-based methods consistently outperform the state-of-the-art methods by improving robustness against variability and reproducibility. The comparative analysis we conducted in this paper will serve as the basis for future research, which will help to refine existing techniques and develop new approaches to address the complexities of stain normalization in complex histopathology images.


Attribute-weighted outlier detection for mixed data based on parallel mutual information

Abstract: Outlier detection plays an important role in data mining because it can improve the performance of data analysis. Most outlier detection algorithms focus on numerical or categorical attributes; however, data typically have a mixture of numerical and categorical attributes. We addressed this problem by developing an attribute-weighted outlier detection algorithm, PMIOD, for high-dimensional and massive mixed data. The PMIOD algorithm adopts mutual information to measure attribute correlations and provides an attribute-weighting method for mixed data. Based on this, an attribute-weighted outlier detection method for mixed data was developed. Moreover, to improve the efficiency of mutual information computing for high-dimensional mixed data, the mutual information computing was parallelized on the Spark platform. We evaluated the proposed algorithm using ten UCI datasets and four synthetic datasets in comparison with widely used algorithms. Experiments were conducted to demonstrate the superiority of the results produced by the proposed algorithm.


Towards self-explainable graph convolutional neural network with frequency adaptive inception

Abstract: Graph convolutional neural networks (GCNs) have demonstrated powerful representing ability of irregular data, e.g., skeletal data and graph-structured data, providing the effective mechanism to fuse the neighbor nodes. However, inheriting from the deep learning, GCN also lacks interpretability, which hinders its application to scenarios that have high demand for transparency. Although, there have been many efforts on the interpretability of deep learning, they mainly concentrate on i.i.d data that is hard to be deployed to GCNs, which involve not only the node feature, but also the graph structure. There are few works that attempt to explain it with post-hoc manner, which can be biased, resulting in mis-representation of the true explanation. Therefore, in this paper, we propose a framework, namely ExpFiGCN, that reveals explainability of the GCNs from the perspective of graph structure and mathematical analysis. Specifically, ExpFiGCN can find the most intrinsically relevant node to the central node and obtain the informative and discriminative signals while performing denoising. For the graph structure, we find K-nearest nodes; for the mathematical analysis, every channel of a node and its neighborhoods contribute dynamically to the final channel signal, which can capture the inherent difference of different channels and neighbor nodes. Meanwhile, it can enhance the representation ability of nodes and ameliorate the over-smoothing problem. On the other hand, our model can dynamically adjust the importance of neighborhoods to the central vertex. We empirically validate the effectiveness of the proposed framework ExpFiGCN on various benchmark datasets. Experimental results show that our method achieves substantial improvements and outperforms the state-of-the-art performance strikingly.


Contrastive sentence representation learning with adaptive false negative cancellation

Abstract: Contrastive sentence representation learning has made great progress thanks to a range of text augmentation strategies and hard negative sampling techniques. However, most studies directly employ in-batch samples as negative samples, ignoring the semantic relationship between negative samples and anchors, which may lead to negative sampling bias. To address this issue, we propose similarity and relative-similarity strategies for identifying potential false negatives. Moreover, we introduce adaptive false negative elimination and attraction methods to mitigate their adverse effects. Our proposed approaches can also be considered semi-supervised contrastive learning, as the identified false negatives can be viewed as either negative or positive samples for contrastive learning in adaptive false negative elimination and attraction methods. By fusing information from positive and negative pairs, contrastive learning learns rich and discriminative representations that capture the intrinsic characteristics of the sentence. Experimental results indicate that our proposed strategies and methods can bring further significant performance improvements. Specifically, the combination of similarity strategy and adaptive false negative elimination method achieves the best results, yielding an average performance gain of 2.1% compared to SimCSE in semantic textual similarity (STS) tasks. Furthermore, our approach is generalizable and can be applied to different text data augmentation strategies and certain existing contrastive sentence representation learning models. Our code and data are publicly available at the link: https://github.com/Linda230/AFNC.


Mapping and discrimination of the mineralization potential in granitoids from Banyo area (Adamawa, Cameroon), using Landsat 9 OLI, ASTER images and field observations

Abstract: The Banyo area is situated in the west Cameroon domain of the Central African Fold Belt. In this study, field data and remote sensing conventional mapping techniques including RGB colour combination (red-green-blue), principal component analysis (PCA), Crosta-PCA, band ratios (BR), constrained energy minimization (CEM), minimum noise fraction (MNF), spectral angle mapper (SAM) classification and linear spectral unmixing (LSU) algorithms were used to process Landsat 9 OLI and ASTER data in order to discriminate various rock units such as biotite-amphibole granites, hornblende-biotite orthogneiss and map associated mineral deposits (e.g., iron-oxide, hydroxyl and corundum minerals) in Banyo area. In addition, it was found that RGB combination (743) of OLI bands, PCA of OLI bands (PC123), BR of OLI bands (4/2, 6/7, 6/5), BR of ASTER (4/2, 7/6, 8/9), Crosta-PCA of OLI bands, MNF (123) of OLI bands, SAM, and LSU techniques applied to ASTER bands ascertain potential locations of granitoids and gneisses bearing iron and hydroxyl minerals in several areas of Banyo. On the other hand, this study also revealed that corundum deposits are detected by applying the CEM method to OLI band ratio 6/7 highlighting red tones and processing SAM classification algorithm both using laboratory reference spectra. Automatic (using PCI Geomatica line tool) and manual extractions of lineaments revealed three major trends (N-S, E-W, and WNW-ESE to NW-SE) and an accessory trend (NE-SW to ENE-WSW) that surround hydrothermally altered rocks recognized as containing iron oxide, hydroxyl, and corundum mineral deposits. In the field, these lineaments may group to the tree deformation phases. The D1 phase (NW-SE); the D2 phase (NE-SW to ENE-WSW) and the D3 phase (N-S). MLC and SAM classification methods showed to be more effective in discriminating rocks bearing Iron-oxide, hydroxyl and corundum minerals in Banyo area. This result permits to confirm that, the combination of remote sensing (Landsat 9 OLI and ASTER data in this case) and field data constitute a useful tool for mineral exploration in the shear zone. However, the accuracy assessment was relied on comparing the different maps produced from Landsat 9 OLI and ASTER data with the ground truth sample points and also, with the earliest geological map of Banyo area. Thus, quantitatively the results were accurate at 99%.


A framework for cyber-risk insurance against ransomware: A mixed-method approach

Abstract: Hackers follow a standard cyber kill chain process and install ransomware payloads using phishing emails on firms belonging to critical industry, resulting in huge losses in revenue, reputation, and customer churn. This study uses a mixed-method explanatory approach to mitigate ransomware attacks. We present the quantitative Ransomware Risk Management Model (R2M2) based on protection motivation theory (PMT). The Ransomware Risk Assessment module based on the threat appraisal component of PMT and the National Institute of Standards and Technology (NIST) guidelines can help the chief information security officer (CISO) to assess the risk using predictive analytics techniques. The Ransomware Risk Quantification module uses collective risk modeling to compute the severity of a ransomware attack on an organization. The Ransomware Risk Mitigation module helps the CISO to minimize the probability and impact of a ransomware attack on their organization by (i) investing in perimeter security technologies and training to ensure prepare, deter, detect, restrain, recover, and review mitigation strategies, (ii) adopting the National Institue of Standards and Technology (NIST) Cybersecurity Framework to ensure business resilience, and (iii) mitigating the residual risk by investing in cyber-risk insurance. We validated the proposed method using a qualitative study by interviewing participants form firms affected by ransomware, managed security service providers, security consultants, and cyber-risk insurers.


Effective image tampering localization with multi-scale ConvNeXt feature fusion

Abstract: With the widespread use of powerful image editing tools, image tampering becomes easy and realistic. Existing image forensic methods still face challenges of low generalization performance and robustness. In this letter, we propose an effective image tampering localization scheme based on ConvNeXt encoder and multi-scale Feature Fusion (ConvNeXtFF). Stacked ConvNeXt blocks are utilized as an encoder to capture hierarchical multi-scale features, which are then fused in decoder for locating tampered pixels accurately. Combined loss function and effective data augmentation strategies are adopted to further improve the model performance. Extensive experimental results show that both localization accuracy and robustness of the ConvNeXtFF scheme outperform other state-of-the-art ones. The source code is available at https://github.com/multimediaFor/ConvNeXtFF.


Hello me, meet the real me: Voice synthesis attacks on voice assistants

Abstract: The radical advances in telecommunications and computer science have enabled a myriad of applications and novel seamless interactions with computing interfaces. Voice Assistants (VAs) have become the norm for smartphones, and millions of VAs incorporated in smart devices are used to control these devices in the smart home context. Previous research has shown that they are prone to attacks, leading vendors to implement countermeasures. One of these measures is to allow only a specific individual, the device's owner, to perform potentially dangerous tasks that may disclose personal information, involve monetary transactions, etc. To understand the extent to which VAs provide the necessary protection to their users, we experimented with two of the most widely used VAs, which the participants trained. We then utilised voice synthesis, using samples provided by participants, to synthesise commands that were used to trigger the corresponding VA and perform a dangerous task. Our extensive results showed that more than 30% of our audio synthesis attacks were successful and at least one successful attack for more than half of the participants. Moreover, they illustrate statistically significant variation among vendors and, in one case, even gender bias. The outcomes are rather alarming and require the deployment of further countermeasures to prevent exploitation, as the number of VAs in use is currently comparable to the world population.


Chatbot ads with a human touch: A test of anthropomorphism, interactivity, and narrativity

Abstract: Powered by artificial intelligence (AI), chatbots are increasingly capable of simulating human-like conversations. But, is this desirable for strategic communications? Will chatbots be more persuasive if they are more human-like, not only in their appearance but also in their interaction and delivery of advertising content? We explored these questions with a 2 (chatbot profile: human-like vs. machine-like) x 2 (message interactivity: high vs. low) x 2 (ad type: narrative vs. factual) experiment (N = 414). Data reveal that high message interactivity fosters positive attitudes toward the chatbot and the ad by mitigating violated expectancy. Narrative ads promote chatbot advertising through perceived transportation. A three-way interaction revealed that when a chatbot is machine-like in appearance, higher interactivity and adoption of a narrative style of delivery serve to increase ad persuasiveness by heightening social presence. Theoretical and practical implications for chatbot advertising are discussed.


A noise-resistant graph neural network by semi-supervised contrastive learning

Abstract: Graph neural networks (GNNs) have been widely applied for representation learning on the graph data in real applications, but few of them are designed to conduct representation learning on the graph data with noisy labels. Its key challenge is that the feature embeddings of nodes with noisy labels (noisy nodes for short) are close to those of unlabeled nodes so that the classifier constructed by GNNs is influenced by noisy nodes. To address this issue, in this paper, we propose a noise-resistant graph neural network with semi-supervised contrastive learning to push noisy nodes far away from unlabeled nodes in the embedding space. To do this, we design a constraint of semi-supervised contrastive learning and put it into the objective function of GNNs. Specifically, the proposed constraint enlarges the distance between noisy nodes and unlabeled nodes by pushing noisy nodes far away from their unlabeled neighbors in the embedding space. As a result, the embeddings of unlabeled nodes are influenced by noisy label less. Moreover, we intuitively analyze the feasibility of our proposed constraint. Comprehensive experiments on real datasets further verify the effectiveness of our proposed method over previous SOTA methods in terms of classification tasks with different ratio levels of noisy labels.


Triple Sequence Learning for Cross-domain Recommendation

Abstract: Cross-domain recommendation (CDR) aims at leveraging the correlation of users’ behaviors in both the source and target domains to improve the user preference modeling in the target domain. Conventional CDR methods typically explore the dual-relations between the source and target domains’ behaviors. However, this may ignore the informative mixed behaviors that naturally reflect the user’s global preference. To address this issue, we present a novel framework, termed triple sequence learning for cross-domain recommendation (Tri-CDR), which jointly models the source, target, and mixed behavior sequences to highlight the global and target preference and precisely model the triple correlation in CDR. Specifically, Tri-CDR independently models the hidden representations for the triple behavior sequences and proposes a triple cross-domain attention (TCA) method to emphasize the informative knowledge related to both user’s global and target-domain preference. To comprehensively explore the cross-domain correlations, we design a triple contrastive learning (TCL) strategy that simultaneously considers the coarse-grained similarities and fine-grained distinctions among the triple sequences, ensuring the alignment while preserving information diversity in multi-domain. We conduct extensive experiments and analyses on six cross-domain settings. The significant improvements of Tri-CDR with different sequential encoders verify its effectiveness and universality. The source code is available at https://github.com/hulkima/Tri-CDR .


Multi-operator opposition-based learning with the neighborhood structure for numerical optimization problems and its applications

Abstract: Opposition-based learning (OBL) is an effective strategy that adjusts the population to accelerate the convergence of the algorithm. However, OBL involves two phases (generation and calculation) that are seldom mentioned simultaneously. Besides, individual information in OBL is not fully used to guide evolution. First, a novel neighborhood generation strategy is proposed to fully use individual information. There are numerous variants of the neighborhood structure. Three prominent neighborhood structures are designed to demonstrate their benefits in various dimensions. Second, a multi-operator calculation method with two distributions is introduced to reach the equilibrium between diversification and intensification. Consequently, this paper proposes three multi-operator neighborhood-based OBL variants (MNOBLs). Compared with the traditional OBL variants, MNOBLs generate the opposite population by using a neighborhood of the individuals. A well-balanced calculation method can lead to good convergence behavior. Subsequently, the proposed MNOBLs are embedded into the basic differential evolution (DE) algorithm to obtain the proposed algorithms. The extensive and rigorous numerical experiments are designed at three levels: strategies, algorithms, and functions. Specifically, the effectiveness and efficiency of the proposed algorithms are verified by comparing them with 13 state-of-the-art DE variants and four metaheuristics on the CEC 2017, and CEC 2022 test suites, and two real-world optimization problems. The comprehensive results show that the proposed OBL variants provide promising results for most problems.


Explainability for Large Language Models: A Survey

Abstract: Large language models (LLMs) have demonstrated impressive capabilities in natural language processing. However, their internal mechanisms are still unclear and this lack of transparency poses unwanted risks for downstream applications. Therefore, understanding and explaining these models is crucial for elucidating their behaviors, limitations, and social impacts. In this article, we introduce a taxonomy of explainability techniques and provide a structured overview of methods for explaining Transformer-based language models. We categorize techniques based on the training paradigms of LLMs: traditional fine-tuning-based paradigm and prompting-based paradigm. For each paradigm, we summarize the goals and dominant approaches for generating local explanations of individual predictions and global explanations of overall model knowledge. We also discuss metrics for evaluating generated explanations and discuss how explanations can be leveraged to debug models and improve performance. Lastly, we examine key challenges and emerging opportunities for explanation techniques in the era of LLMs in comparison to conventional deep learning models.


Balancing Innovation and Security in the Cloud

Abstract: This chapter delves into the intricate relationship between innovation and security in the digital age. It highlights the challenges of the digital age and the transformative impact of cloud computing, emphasizing its role in driving innovation. The chapter also delves into cloud service and deployment models, discussing the benefits and challenges of cloud security. It also discusses the role of innovation in driving progress through case studies and addressing challenges organizations face. The chapter also discusses risk assessment and mitigation in the cloud, compliance, regulatory challenges, legal and ethical considerations, and best practices. It also explores emerging technologies like AI and machine learning, Zero Trust security, and future directions.


Autoencoders and their applications in machine learning: a survey

Abstract: Abstract Autoencoders have become a hot researched topic in unsupervised learning due to their ability to learn data features and act as a dimensionality reduction method. With rapid evolution of autoencoder methods, there has yet to be a complete study that provides a full autoencoders roadmap for both stimulating technical improvements and orienting research newbies to autoencoders. In this paper, we present a comprehensive survey of autoencoders, starting with an explanation of the principle of conventional autoencoder and their primary development process. We then provide a taxonomy of autoencoders based on their structures and principles and thoroughly analyze and discuss the related models. Furthermore, we review the applications of autoencoders in various fields, including machine vision, natural language processing, complex network, recommender system, speech process, anomaly detection, and others. Lastly, we summarize the limitations of current autoencoder algorithms and discuss the future directions of the field.


Variational quantum time evolution without the quantum geometric tensor

Abstract: Real- and imaginary-time quantum state evolutions are crucial in physics and chemistry for exploring quantum dynamics, preparing ground states, and computing thermodynamic observables. On near-term devices, variational quantum time evolution is a promising candidate for these tasks, as the required circuit model can be tailored to the available devices' capabilities. Due to the evaluation of the quantum geometric tensor (QGT), however, this approach quickly becomes infeasible for relevant system sizes. Here, we propose a dual formulation for variational time evolution, which replaces the calculation of the QGT by solving a fidelity-based optimization to compute updates to the dynamics in each time step. We demonstrate our algorithm for the time evolution of the Heisenberg Hamiltonian and show that it accurately reproduces the system dynamics at a fraction of the cost of standard variational quantum time evolution algorithms.


Analysis on unit maximum capacity of orthogonal multiple watermarking for multimedia signals in B5G wireless communications

Abstract: B5G aims to meet the demands of today's growing mobile traffic and expand the communication space. Considering that the intelligent application to B5G wireless communications will involve the security issues of user data and operational data, in this paper, the maximum capacity problem of the multi-watermarking method in multimedia signal hiding is studied to alleviate the information security problem of B5G. In the analyzed multi-watermarking process, the Spread Transform Dither Modulation is employed. During the watermarking procedures, through Gram-Schmidt orthogonalization, we can obtain the multiple spreading vectors. Consequently, the multiple watermarks can be simultaneously embedded into the same position of multimedia signal. Moreover, the multiple watermarks can be extracted without affecting one another during the extraction process. In our research, we intensively analyze the effect of the size of the spreading vector on the unit maximum capacity; consequently, we discover the hidden theoretical relationship between the size of the spreading vector and the unit maximum capacity. Many experiments have been conducted to seek out the optimal parameter values, with which the method can achieve the highest robustness, on the premise of possessing high capacity and good imperceptibility.


Transformer Driven Matching Selection Mechanism for Multi-Label Image Classification

Abstract: Graph Matching has recently emerged as an attractive technique applied to various computer vision tasks. Graph Matching based multi-label image classification, in particular, treats each image as a bag of instances and reformulates the classification task as an instance-label matching selection problem, achieving state-of-the-art results on diverse benchmarks. However, the generalization and scalability of such learned model cannot be well guaranteed due to its manually predetermined graph structure and high-dimension embedding of dense connections between instances and labels. To address these limitations, in this work, we propose a novel Transformer Driven Matching Selection framework for Multi-Label Image Classification (C-TMS), where instance structural relationships, class-wise global dependencies, and the co-occurrence possibility of varying instance-label assignments are simultaneously taken into consideration in a unified and adaptive manner. Moreover, the parallelization capability of the Transformer enables efficient computation, making our model scalable to large-scale datasets. Specifically, we first represent instances and labels as nodes in the visual space and label space respectively, and then compute the hidden representation of each node in its individual space, by attending a self-attention strategy over its entire neighborhood. Subsequently, the cross-attention is adopted to excavate the correct assignments between instances and labels, and further interprets how classifying each label depends on the instances within an image and its interaction with other labels. Finally, an asymmetric focal loss is designed to optimize the instance-label correspondence, and read out image-level category confidences. Extensive experiments conducted on various multi-label image datasets demonstrate the superiority of our proposed method.


A Multihead Attention Self-Supervised Representation Model for Industrial Sensors Anomaly Detection

Abstract: Industrial sensors capture critical information for intelligent manufacturing maintenance. To promote equipment upgrading and manufacturing processes, intelligent decisions, and information learning play an important role. Although deep learning methods historically obtain excellent results, there is always a trade-off between fine-tuning existing networks or designing models from scratch for sensor data processing. In this paper, we propose the multi-head attention self-supervised (MAS) representation model, which is a self-supervised learning-based sensor feature extraction network. To the best of our knowledge, this is the first time a self-supervised contrastive learning method using positive samples that represent multi-dimensional industry sensor data is being used for anomaly detection. We review alternative data augmentation methods proposed for better-representing sensor sequence data. We use this insight to design a new structure that adapts to the temporal characteristics of the application. We apply our method to a real-world water circulation system that uses a variety of industrial sensors. The effectiveness of the proposed MAS methods is demonstrated.


TrafAda: Cost-Aware Traffic Adaptation for Maximizing Bitrates in Live Streaming

Abstract: The business growth of live streaming causes expensive bandwidth costs from the Content Delivery Network service. It necessitates traffic adaptation, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">i.e. , adapting video bitrates for cost-efficient bandwidth utilization, especially under the 95  th  percentile pricing. However, our data-driven investigations indicate the existing methods are hard to achieve bitrate-cost balance in a long month-level billing cycle due to dynamic traffic patterns. We propose <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">TrafAda , a learning-based cost-aware traffic adaptation method consisting of i) an ultra-long-term bandwidth demand forecasting model to learn complex bandwidth usage patterns, and ii) an imitation learning-based bitrate decision mechanism to optimize the ultra-long-term objective. We have implemented and deployed <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">TrafAda on a large-scale live streaming system in China serving over one billion viewers from 388 cities. The results show that <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">TrafAda improves peak-hour bitrate, quality of experience (QoE), and watching time by 34.75%, 44.56%, and 10.68%, respectively, without extra bandwidth cost, which can be converted to a considerable value for a commercial system.


Toward Fast Personalized Semi-Supervised Federated Learning in Edge Networks: Algorithm Design and Theoretical Guarantee

Abstract: Recent years have witnessed a huge demand for artificial intelligence and machine learning applications in wireless edge networks to assist individuals with real-time services. Federated learning (FL) has emerged as a suitable and appealing distributed learning paradigm to deploy these applications at the network edge. Despite the many successful efforts made to apply FL to wireless edge networks, the adopted algorithms mostly follow the same spirit as FedAvg, thereby heavily suffering from the practical challenges of label deficiency and device heterogeneity. These challenges not only decelerate the model training in FL but also downgrade the application performance. In this paper, we focus on the algorithm design and address these challenges by investigating the personalized semi-supervised FL problem and proposing an effective algorithm, named FedCPSL. In particular, the techniques of pseudo-labeling, and interpolation-based model personalization are judiciously combined to provide a new problem formulation for personalized semi-supervised FL. The proposed FedCPSL algorithm employs novel strategies, including adaptive client variance reduction, local momentum, and normalized global aggregation, to combat the challenge of device heterogeneity and boost algorithm convergence. The convergence property of FedCPSL is also thoroughly analyzed and shows that FedCPSL is resilient to both statistical and system heterogeneity, obtaining a sublinear convergence rate. Experimental results on image classification tasks are presented to demonstrate that the proposed approach outperforms its counterparts in terms of both convergence speed and application performance.


Light Field Salient Object Detection With Sparse Views via Complementary and Discriminative Interaction Network

Abstract: 4D light field data record the scene from multiple views, thus implicitly providing beneficial depth cue for salient object detection in challenging scenes. Existing light field salient object detection (LF SOD) methods usually use a large number of views to improve the detection accuracy. However, using so many views for LF SOD brings difficulties to its practical applications. Considering that adjacent views in a light field are actually with very similar contents, in this work, we propose defining a more efficient pattern of input views, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">i.e ., key sparse views, and design a network to effectively explore the depth cue from sparse views for LF SOD. Specifically, we firstly introduce a low rank-based statistical analysis to the existing LF SOD datasets, which allows us to conclude a fixed yet universal pattern for our key sparse views, including the number and positions of views. These views maintain the sufficient depth cue, but greatly lower the number of views to be captured and processed, facilitating practical applications. Then, we propose an effective solution with a key Complementary and Discriminative Interaction Module (CDIM) for LF SOD from key sparse views, named CDINet. The CDINet follows a two-stream structure to extract the depth cue from the light field stream ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">i.e ., sparse views) and the appearance cue from the RGB stream ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">i.e ., center view), generating features and initial saliency maps for each stream. The CDIM is tailored for inter-stream interaction of both these features and saliency maps, using the depth cue to complement the missing salient regions in RGB stream and discriminate the background distraction, to enhance the final saliency map further. Extensive experiments on three LF multi-view datasets demonstrate that our CDINet not only outperforms the state-of-the-art 2D methods, but also achieves competitive performance as compared with the state-of-the-art 3D and 4D methods. The code and results of our method are available at https://github.com/GilbertRC/LFSOD-CDINet.


Dynamic Clustering and Power Control for Two-Tier Wireless Federated Learning

Abstract: Federated learning (FL) has been recognized as a promising distributed learning paradigm to support intelligent applications at the wireless edge, where a global model is trained iteratively through the collaboration of the edge devices without sharing their data. However, due to the relatively large communication cost between the devices and parameter server (PS), direct computing based on the information from the devices may not be resource efficient. This paper studies the joint communication and learning design for the over-the-air computation (AirComp)-based two-tier wireless FL scheme, where the lead devices first collect the local gradients from their nearby subordinate devices, and then send the merged results to the PS for the second round of aggregation. We establish a convergence result for the proposed scheme and derive the upper bound on the optimality gap between the expected and optimal global loss values. Next, based on the device distance and data importance, we propose a hierarchical clustering method to build the two-tier structure. Then, with only the instantaneous channel state information (CSI), we formulate the optimality gap minimization problem and solve it by using an efficient alternating minimization method. Numerical results show that the proposed scheme outperforms the baseline ones.


HVMM: A Holistic Virtual Machine Management Strategy for Cloud Data Centers

Abstract: Cloud computing has emerged as an infrastructure in the era of digital economy and has been widely applied in various fields. Virtual Machine(VM) management is the key mechanism in a Cloud Data Center(CDC). A typical VM management system is responsible for VM allocation and VM reallocation, and it is usually designed to optimize specific objectives, especially for the metrics of energy consumption, resource wastage, communication cost, and Service Level Agreement Violations (SLAV). However, it is greatly challenging to optimize these metrics at the same time, and most existing VM management strategies focus on optimizing part of the above four metrics. In this paper, we propose a Holistic Virtual Machine Management (HVMM) strategy to optimize the energy consumption, resource wastage, communication cost, and SLAV simultaneously. First, we define two parameters, the Compatibility and the Performance-to-Power Ratio (PPR), for VM allocation to optimize energy consumption and resource wastage. Then, we propose a reallocation approach based on spectral clustering that can handle dynamic traffic between VMs without a priori knowledge of the traffic between VMs, and it takes a slight expense of resource wastage and energy consumption to reduce communication cost between VMs and ensures low SLAV risk. To evaluate the performance of HVMM, we compared the proposed strategy with the state-of-the-art strategies in various experiments on real-world traces. Compared with the other strategies, the resource wastage of HVMM is reduced by 62%. Simultaneously, the communication cost is reduced by about 26%, the energy consumption is reduced by about 5%, and SLAV is much lower than that of the others.


An Adaptive Post-Processing Network With the Global-Local Aggregation for Semantic Segmentation

Abstract: Current semantic segmentation methods mainly focus on modeling the context of the global image to obtain high-quality segmentation results. However, they ignore the role of local image patches, which contain complementary and effective context information. In this paper, we propose an adaptive post-processing network (APPNet) for semantic segmentation based on the predictions of current methods in the global image and local image patches. The key point of APPNet is the global-local aggregation module, which models the context between global predictions and local predictions to generate accurate pixel-wise representation. Furthermore, we develop an adaptive points replacement module to compensate for the lack of fine detail in global prediction and the overconfidence in local predictions. Our method can be readily integrated into existing segmentation methods (i.e., ConvNeXt, HRNet, ViT-Adapter) with little memory and without extra modification in current models. We empirically demonstrate our method brings performance improvements across diverse datasets (i.e., Cityscapes, ADE20K, PASCAL-Context, COCO-Stuff). The code and models will be publicly available at https://github.com/zhu-gl-ux/APPN.


Multi-Task Learning With Multi-Query Transformer for Dense Prediction

Abstract: Previous multi-task dense prediction studies developed complex pipelines such as multi-modal distillations in multiple stages or searching for task relational contexts for each task. The core insight beyond these methods is to maximize the mutual effects of each task. Inspired by the recent query-based Transformers, we propose a simple pipeline named Multi-Query Transformer (MQTransformer) that is equipped with multiple queries from different tasks to facilitate the reasoning among multiple tasks and simplify the cross-task interaction pipeline. Instead of modeling the dense per-pixel context among different tasks, we seek a task-specific proxy to perform cross-task reasoning via multiple queries where each query encodes the task-related context. The MQTransformer is composed of three key components: shared encoder, cross-task query attention module and shared decoder. We first model each task with a task-relevant query. Then both the task-specific feature output by the feature extractor and the task-relevant query are fed into the shared encoder, thus encoding the task-relevant query from the task-specific feature. Secondly, we design a cross-task query attention module to reason the dependencies among multiple task-relevant queries; this enables the module to only focus on the query-level interaction. Finally, we use a shared decoder to gradually refine the image features with the reasoned query features from different tasks. Extensive experiment results on two dense prediction datasets (NYUD-v2 and PASCAL-Context) show that the proposed method is an effective approach and achieves state-of-the-art results. Code and models are available at https://github.com/yangyangxu0/MQTransformer.


Online Research Topic Modeling and Recommendation Utilizing Multiview Autoencoder-Based Approach

Abstract: Recent years have witnessed tremendous growth in the publication of research articles as well as in the rise of new research topics. Articles get published in a streaming manner and therefore retrieving and recommending trending topics continuously by updating the trend of topics with time will be beneficial for young researchers. The proposed topic recommendation system is a clustering-based approach that utilizes an autoencoder framework for the generation of clusters. The autoencoder framework considers articles as input in a multiview framework and produces latent data in lower-dimensional space using graph attention-based encoder and decoder networks. The latent data is then partitioned with respect to its different views and finally, a single consensus overlapping partitioning is produced by satisfying all the views. Since the publication of articles is a continuous process, to update the trending topics continuously, the clustering-based approach is kept on and applied iteratively in a sliding window manner. The generated clusters are analyzed to extract the trending topics and recommendations for future scope. An article can belong to multiple topics and the proposed method is developed by considering such criteria and therefore tested with the modified version of the multilabel scientific article data ArXiv, named CSML.ArXiv. The superiority of the proposed method can be observed from its comparisons with existing methods, and a few baseline methods with respect to cluster formation, topic extraction, and trending topic evaluation.


Efficient Pairing-Free Certificateless Signcryption Scheme for Secure Data Transmission in IoMT

Abstract: The Internet of Medical Things (IoMT) builds a bridge between patients and doctors, facilitating patients’ being diagnosed and monitored by uploading physiological indicators without visiting the hospital. However, physiological indicators are sensitive data of patients, making it a challenge to achieve verifiability of data sources while ensuring data privacy during data transmission of IoMT. Due to its ease of deployment and the ability to provide both encryption and signature, CertificateLess SignCryption (CLSC) is suitable for designing secure data-transfer protocol in IoMT. Nevertheless, internal adversaries “malicious users" and “malicious KGC", capable of launching Type I and Type II attacks, threaten the security of present CLSC schemes, making most of them insecure. In this work, after giving an example of a recent CLCS scheme suffering Type I attack, we propose an efficient pairing-free CLCS scheme suitable for secure data transmission in IoMT based on the idea of zero-knowledge proof. It not only provides confidentiality and unforgeability of transmitted data under the Type I and Type II attacks, but also achieves lower computational and communication overhead, and public verifiability. Finally, compared with the five recent CLSC schemes, theoretical analysis and experimental testing results show that the proposed scheme outperforms the other five schemes in terms of computation and communication costs as well as security. Therefore, our scheme is better suited for constructing secure data transmission in IoMT scenarios.


Federated Domain Generalization: A Secure and Robust Framework for Intelligent Fault Diagnosis

Abstract: The maturation of sensor network technologies has promoted the emergence of the Industrial Internet of Things, which has been collecting an increasing volume of monitoring data. Transforming these data into actionable intelligence for equipment fault diagnosis can reduce unscheduled downtime and performance degradation. In conventional artificial intelligence paradigms, abundant individual data distributed across clients’ devices needs to be delivered to a central storage for data analysis and knowledge extraction, which may violate data privacy requirements and neglect distribution discrepancy across different clients. To tackle the issue of privacy disclosure, an edge-cloud integrated federated learning framework is developed. Then, a two-stage training mechanism is designed to establish a domain-agnostic fault diagnosis model that can achieve satisfactory diagnostic performance on unseen target domains. Comprehensive simulated experiments on two rotating machines indicate that the proposed method possesses good generalization ability and can meet the requirement of privacy protection.


CC-FedAvg: Computationally Customized Federated Averaging

Abstract: Federated learning (FL) is an emerging paradigm to train model with distributed data from numerous Internet of Things (IoT) devices. It inherently assumes a uniform capacity among participants. However, due to different conditions such as differing energy budgets or executing parallel unrelated tasks, participants have diverse computational resources in practice. Participants with insufficient computation budgets must plan for the use of restricted computational resources appropriately, otherwise they would be unable to complete the entire training procedure, resulting in model performance decline. To address this issue, we propose a strategy for estimating local models without computationally intensive iterations. Based on it, we propose Computationally Customized Federated Averaging (CC-FedAvg), which allows participants to determine whether to perform traditional local training or model estimation in each round based on their current computational budgets. Both theoretical analysis and exhaustive experiments indicate that CC-FedAvg has the same convergence rate and comparable performance as FedAvg without resource constraints. Furthermore, CC-FedAvg can be viewed as a computation-efficient version of FedAvg that retains model performance while considerably lowering computation overhead.


An In-Depth Look at Forking-Based Attacks in Ethereum With PoW Consensus

Abstract: In this paper, we analyze the performance of Ethereum data distribution network using a probabilistic model which allows accurate modeling of data propagation but also of forking, which happens when the blockchain maintained by the network temporarily splits into multiple versions due to a disagreement over the validity of a particular block. We also investigate the duration of inconsistent states of the ledger, which refers to the amount of time that the network remains split or partitioned. Finally, we model the block withholding attack and block slowdown attack, and analyze their impact on network performance of the network in terms of quality indicators such as block delivery time, the duration of ledger inconsistency, and forking probability. We also propose countermeasures for the block withholding attack.


Switching-Event-Based Interval Type-2 Fuzzy Control for a Class of Uncertain Nonlinear Systems

Abstract: In this paper, a switching-event-based interval type-2 variable universe fuzzy tracking control strategy is proposed for a class of uncertain nonlinear systems. Remarkably, the nonlinearities and the large unknown uncertainties (including parametric and structural) can be allowed. Therefore, a novel switching-event-based mechanism (SEBM) is proposed. It not only determines when to update the control law, but also when to update the design parameters. At the same time, generous computing resources are saved. In addition, the interval type-2 fuzzy control (IT2FC) technology is introduced to resist unknown uncertainties by identifying the controlled model online. Moreover, the Lyapunov function is designed to prove that the Zeno phenomenon does not occur and the closed-loop system is asymptotically stable. Finally, two practical simulations are given to demonstrate the effectiveness of the proposed method.


Differentiable Rendering for Synthetic Aperture Radar Imagery

Abstract: There is rising interest in differentiable rendering, which allows explicitly modeling geometric priors and constraints in optimization pipelines using first-order methods such as backpropagation. Incorporating such domain knowledge can lead to deep neural networks that are trained more robustly and with limited data, as well as the capability to solve ill-posed inverse problems. Existing efforts in differentiable rendering have focused on imagery from electro-optical sensors, particularly conventional RGB-imagery. In this work, we propose an approach for differentiable rendering of Synthetic Aperture Radar (SAR) imagery, which combines methods from 3D computer graphics with neural rendering. We demonstrate the approach on the inverse graphics problem of 3D Object Reconstruction from limited SAR imagery using high-fidelity simulated SAR data.


Federated Learning for Crowd Counting in Smart Surveillance Systems

Abstract: Crowd counting in smart surveillance systems plays a crucial role in Internet of Things (IoT) and smart cities, and can affect various aspects such as public safety, crowd management, and urban planning. Using surveillance data to centrally train a crowd counting model raises significant privacy concerns. Traditional methods try to alleviate the concern by reducing the focus on individuals, but the concern still needs to be thoroughly resolved. In this work, we develop a horizontal federated learning (HFL) framework to train the crowd counting models which can preserve privacy simultaneously. This framework enables the smart surveillance system to learn from model aggregation without accessing the private data stored on local devices. Therefore, it eliminates the need for video data transmission, reduces communication costs, and avoids raw data leakage. Due to the lack of FL crowd counting datasets, we design four non-IID (non-Independent and Identically Distributed) partitioning strategies, including feature-skew, quantity-skew, scene-skew, and time-skew, to simulate real-world FL scenarios. In addition, we present an efficient fully convolutional network (e-FCN) for each client to demonstrate the practical applicability of the proposed framework. The e-FCN adopts an encoder-decoder architecture with fewer parameters, making it communication-friendly and easier to train. This design can achieve competitive performance compared to more complex models in surveillance crowd counting in literature. Finally, we evaluate the proposed HFL framework with e-FCN under our skew strategies on multiple real-world datasets, including Crowd Surveillance, ShanghaiTech PartB, WorldExpo’10, FDST, CityUHK-X, UCSD, and MALL. Extensive experiments allow us to present our developed Federated Crowd Counting benchmark as a reference for future research and provide guidance for FL algorithm selection in smart surveillance system deployment.


Feature interaction and two-stage cross-modal fusion for RGB-D salient object detection

Abstract: Most existing RGB-D salient object detection (SOD) methods extract features of both modalities in parallel or adopt depth features as supplementary information for unidirectional interaction from depth modality to RGB modality in the encoder stage. These methods ignore the influence of low-quality depth maps, and there is still room for improvement in effectively fusing RGB features and depth features. To address the above problems, this paper proposes a Feature Interaction Network (FINet), which performs bi-directional interaction through feature interaction module (FIM) in the encoder stage. The feature interaction module is divided into two parts: depth enhancement module (DEM) filters the noise in the depth features through the attention mechanism; and cross enhancement module (CEM) effectively interacts RGB features and depth features. In addition, this paper proposes a two-stage cross-modal fusion strategy: high-level fusion adopts the semantic information of high level for coarse localization of salient regions, and low-level fusion makes full use of the detailed information of low level through boundary fusion, and then we progressively refine high-level and low-level cross-modal features to obtain the final saliency prediction map. Extensive experiments show that the proposed model achieves better performance than eight state-of-the-art models on five standard datasets.


An LDP-Based Privacy-Preserving Longitudinal and Multidimensional Range Query Scheme in IoT

Abstract: Range queries are extensively used in various Internet of Things (IoT) applications as an essential functional requirement to provide intelligent and personalized services to users. In IoT environments, diverse types of data are generated, necessitating the design of range query schemes for multidimensional data. Privacy preservation is a key concern for range queries, leading to the proposal of several privacy-preserving solutions. However, most of these solutions are either inefficient or impractical. Moreover, existing approaches often suffer from the problem of longitudinal data privacy leakage, posing a serious threat to user privacy. Although some efforts have addressed the privacy issues of longitudinal data, practical implementations have been hesitant. To tackle these challenges, we propose a Local Differential Privacy-based (LDP) privacy-preserving scheme called the Privacy-Preserving Longitudinal and Multidimensional Range Query (PLMRQ) for IoT. Our scheme focuses on lightweight privacy preservation and eliminates the need for a trusted third party (TTP). Firstly, it is designed based on a double randomizer, ensuring effective privacy preservation of longitudinal data over time. Secondly, to mitigate excessive noise injection, PLMRQ dynamically constructs a binary tree structure by hierarchically decomposing the entire domain. Finally, through the utilization of a post-processing technique, the mean square error is efficiently reduced. Theoretical and experimental results demonstrate that the proposed PLMRQ maintains competitive utility while rigorously satisfying lneϵ1+tϵ2+1/eϵ1+etϵ2-LDP with an upper bound of ϵ1 and a lower bound of ϵ2.


The Application of Artificial Intelligence in Alzheimer's Research

Abstract: Alzheimer's disease (AD) is an irreversible and neurodegenerative disease that slowly impairs memory and neurocognitive function, but the etiology of AD is still unclear. With the explosive growth of electronic health data, the application of artificial intelligence (Al) in the healthcare setting provides excellent potential for exploring etiology and personalized treatment approaches, and improving the disease's diagnostic and prognostic outcome. This paper first briefly introduces Al technologies and applications in medicine, and then presents a comprehensive review of Al in AD. In simple, it includes etiology discovery based on genetic data, computer-aided diagnosis (CAD), computer-aided prognosis (CAP) of AD using multi-modality data (genetic, neuroimaging and linguistic data), and pharmacological or non-pharmacological approaches for treating AD. Later, some popular publicly available AD datasets are introduced, which are important for advancing Al technologies in AD analysis. Finally, core research challenges and future research directions are discussed.


Joint Sample Position Based Noise Filtering and Mean Shift Clustering for Imbalanced Classification Learning

Abstract: The problem of imbalanced data classification learning has received much attention. Conventional classification algorithms are susceptible to data skew to favor majority samples and ignore minority samples. Majority weighted minority oversampling technique (MWMOTE) is an effective approach to solve this problem, however, it may suffer from the shortcomings of inadequate noise filtering and synthesizing the same samples as the original minority data. To this end, we propose an improved MWMOTE method named joint sample position based noise filtering and mean shift clustering (SPMSC) to solve these problems. Firstly, in order to effectively eliminate the effect of noisy samples, SPMSC uses a new noise filtering mechanism to determine whether a minority sample is noisy or not based on its position and distribution relative to the majority sample. Note that MWMOTE may generate duplicate samples, we then employ the mean shift algorithm to cluster minority samples to reduce synthetic replicate samples. Finally, data cleaning is performed on the processed data to further eliminate class overlap. Experiments on extensive benchmark datasets demonstrate the effectiveness of SPMSC compared with other sampling methods.


Multilingual personalized hashtag recommendation for low resource Indic languages using graph-based deep neural network

Abstract: Users from different cultures and backgrounds often feel comfortable expressing their thoughts on trending topics by generating content in their regional languages. Recently, there has been an explosion in multilingual information, and a massive amount of multilingual textual data is added daily on the Internet. Using hashtags for multilingual low-resource content can be an effective way to overcome language barriers because it allows content to be discovered by a wider audience and makes it easier for people interested in the topic to find relevant content, regardless of the language in which it was written. To account for linguistic diversity and universal access to information, hashtag recommendation for multilingual low-resource content is essential. Several approaches have been put forth to recommend content-based and personalized hashtags for multimodal content in high-resource languages. Data availability and linguistic differences often limit the development of hashtag recommendation methods for low-resource Indic languages. Hashtag recommendation for tweets disseminated in low-resource Indic languages has seldom been addressed. Moreover, personalization and language usage aspects to recommend hashtags for tweets posted in low-resource Indic languages have yet to be explored. In view of the foregoing, we propose an automated hashtag recommendation system for tweets posted in low-resource Indic languages dubbed as TAGALOG, capable of recommending personalized and language-specific hashtags. We employ user-guided and language-guided attention mechanisms to distill indicative features from low-resource tweets according to the user's topical and linguistic preferences. We propose a graph-based neural network to mine users' posting behavior by connecting historical tweets of a particular user and language relatedness by linking tweets according to language families, i.e., Indo-Aryan and Dravidian. Experimental results on the curated dataset from Twitter demonstrate that the proposed model outperformed recognized pre-trained language models and extant research, showing an average improvement of 12.3% and 12.8% in the F1-score, respectively. TAGALOG recommends hashtags that align with the user's interests and linguistic predilections, leading to a heightened level of tailored and engaging user experience. Personalized and multilingual hashtag recommendation systems for low-resource Indic languages can help to improve the discoverability and relevance of content in these languages.


A hybrid search mode-based differential evolution algorithm for auto design of the interval type-2 fuzzy logic system

Abstract: This article proposed a hybrid search mode-based differential evolution (HSM-DE) algorithm to overcome the complex design of an interval type-2 fuzzy logic system (IT2FLS). First, transform complex design processes of the IT2FLS into optimization problems for our proposed evolutionary algorithm by decoding the whole system into design parameters regarded as search objectives. Then, the DE algorithm with a rapid convergence characteristic is adopted as a global search method for exploration according to a memetic algorithm (MA) structure. Considering the conventional DE algorithm is lack of escaping ability for the local optimal solution, a local search method combined with a simulated binary crossover (SBX) and polynomial mutation (PM) is utilized to enhance the exploitation behavior of our proposed method. In addition, simple constraints on the design parameters of the membership function are added to balance the searching freedom of the HSM-DE algorithm and the readability of the optimal IT2FLS. Finally, a simulation of a mobile two-wheel vehicle (MTWV) under a goal search task is performed to verify the effectiveness of the optimal IT2FLS auto designed by HSM-DE. All results demonstrate that the HSM-DE realizes auto design for the IT2FLS with high-performance control and outperforms the comparative methods. Moreover, four comparison methods are performed to validate the high-performance of the proposed HSM-DE on the search ability of the optimal solution.


Accelerating Federated Learning With Data and Model Parallelism in Edge Computing

Abstract: Recently, edge AI has been launched to mine and discover valuable knowledge at network edge. Federated Learning, as an emerging technique for edge AI, has been widely deployed to collaboratively train models on many end devices in data-parallel fashion. To alleviate the computation/communication burden on the resource-constrained workers (e.g., end devices) and protect user privacy, Spilt Federated Learning (SFL), which integrates both data parallelism and model parallelism in Edge Computing (EC), is becoming a practical and popular approach for model training over distributed data. However, apart from the resource limitation, SFL still faces two other critical challenges in EC, i.e., system heterogeneity and context dynamics. To overcome these challenges, we present an efficient SFL method, named, which controls both local updating frequency and batch size to better accelerate model training. We theoretically analyze the model convergence rate and obtain a convergence upper bound regarding local updating frequency given a fixed batch size. Upon this, we develop a control algorithm to determine adaptive local updating frequency and diverse batch sizes for heterogeneous workers to enhance the training efficiency. The experimental results show that can reduce the completion time by about 43% and the network traffic consumption by about 31% for achieving the similar test accuracy, compared to the baselines.


IoMT: A Medical Resource Management System Using Edge Empowered Blockchain Federated Learning

Abstract: As data sharing on the Internet of Medical Things (IoMT) become more complicated, the problems of divergent interests, unregulated policies, privacy and security, and the resource constraints of data owners have drawn the attention of researchers. To address the problems, this paper provides resource management in the IoMT using a proposed edge-empowered blockchain federated learning system. Also, an improved linear regressor model is proposed as the global learning model for the federated learning system. Gradient parameters are encrypted using Paillier encryption on the federated server side before they are shared by the federated clients. Blockchain is deployed to provide new security features for IoMT and edge computing. Moreover, all transactions of IoMT and edge devices are stored on the blockchain for secure cataloguing and auditing. Edge computing is employed to handle complex computing tasks on behalf of IoMT devices. Extensive simulations are conducted to validate the efficacy of the proposed system model. The results show that computing costs are minimized while still achieving the benefits of security and privacy in the proposed system. Furthermore, security analysis shows that the proposed system is protected from security attacks.


Secure and optimized satellite image sharing based on chaotic eπ map and Racah moments

Abstract: The objective of this paper is to contribute to the sharing, transfer, and secured indexing of large color images. Watermarking and digital encryption have emerged as alternative and complementary solutions to ensure authorized access, facilitate authentication of content, or prevent illegal reproduction. For this reason, we suggest a new system based on four techniques derived from various transformation and decomposition methods, such as the discrete orthogonal Racah moment transformations (DORMT), which allows the information capacity to be reduced to a number of coefficients, as well as the discrete wavelet transform (DWT), which makes it possible to decompose into a certain number of multilevel sub-bands, to have the sub-band that represents most of the image information. In addition, Schur decomposition (SD) and singular value decomposition (SVD) have been used to increase security. The proposed system consists of two main phases. The first phase is the integration of a color watermark, first applying DORMT-SD-SVD to a color host image and then applying DWT-SD-SVD to achieve a compromise between capacity, invisibility and robustness in terms of quality and privacy. The second phase is the encryption of the watermarked image with an eπ map to increase security for sharing, transfer and indexing. This system uses an Aquila Optimization Algorithm (AOA) as an optimization procedure to find the best set of DORMT parameters and provide a dynamic and adaptive scale factor. The experimental results, in which the proposed system's properties are tested and compared to those of other systems, make it clear that the proposed system is useful in terms of its level of security, capacity, invisibility, and resistance to attacks that use signal processing.


Semi-fragile neural network watermarking for content authentication and tampering localization

Abstract: As an emerging digital product, artificial intelligence models face the risk of being modified. Malicious tampering will severely damage model functions, which is different from normal modifications. In addition, tampering localization for targeted repair can effectively reduce the cost. Therefore, it is crucial to achieve model content authentication and locate the tampering location. We proposed a novel semi-fragile neural network watermarking method in this paper to address these issues. Specifically, with the precondition of maintaining model performance, we proposed a method that generates a set of semi-fragile samples for a model to achieve the content authentication and tampering localization. The experiment results show that the content authentication of the model can be achieved by analyzing the output results of the model for the semi-fragile samples. When the model is processed normally, the output results are consistent with the expected label, while when the model is maliciously tampered with, the model produces unstable output. Furthermore, the tamper localization of the model can be further achieved through the information hidden in the semi-fragile samples, resulting in an average accuracy of more than 99.42%. In addition, our method is also effective for other deep neural networks.


A Genetic Algorithm-based sequential instance selection framework for ensemble learning

Abstract: The accumulation of large amounts of historical data has led to the wide application of ensemble learning over the past few decades, but the balance between the individual accuracy of base classifiers (BCs) and the diversity among these BCs is rarely considered in the construction of ensemble models. Since such a balance is crucial to the success of ensemble models, this paper proposes a Genetic Algorithm-based sequential instance selection framework to address this research gap. The novelties of the proposed framework include: transforming the balance between the individual accuracy of BCs and the diversity among BCs into a general combinatorial optimization model and designing a Genetic Algorithm-based evolutionary instance selection method to solve this model. The proposed framework not only overcomes the inherent limitations of the Genetic Algorithm in some high-dimensional tasks but also provides an explicit and automatic way to balance the accuracy and diversity by searching appropriate training data subsets for different component BCs. Based on obtained training data subsets, the component BCs of the ensemble model are generated sequentially, and their predictions are further combined with the weighted majority voting rule. Using 30 real datasets collected from various practical applications, such as medicine, business, and industry, the effectiveness of the proposed framework in constructing powerful ensemble models is examined and compared with six benchmark ensemble learning methods. In addition, the capability of the proposed framework to improve convergence performances is also examined by the comparison with the traditional Genetic Algorithm.


Eye detection and coarse localization of pupil for video-based eye tracking systems

Abstract: A video-based eye tracking system generally captures NIR images, each of which contains one or two eyes of a subject. The subject's point of gaze is then determined using 3D eye model and pupil centre corneal reflection technique. Eye detection and pupil localization play significant roles in video-based eye tracking systems. However, face rotation, wearing glasses, eye-shape variation and illumination variation make it difficult to detect an eye and localize a pupil accurately in the images captured by video-based eye tracking systems. In this paper, we proposed an eye detector that adopts a coarse-to-fine strategy. The eye detector consists of three classifiers: an ATLBP-THACs feature-based cascade classifier, a branch CNN and a multi-task CNN. We also proposed a method for coarse pupil localization. Coarse localization is an important step for pupil localization since it can provide initial pupil coordinates for a fine pupil localization method. Given a downscaled eye image, a shallow CNN is used to estimate the location of seven landmarks. On this basis, pupil center and radius are estimated. A method for small dim target enhancement is used to increase the contrast between pupil and background. The main goal of pupil enhancement is to make it easier to binarize an eye image. At last, component filtering is made by utilizing the estimated pupil center and radius. We collected a dataset named neepuEYE dataset that consists of 5500 NIR eye images from 109 people. The images can be used to generate augmented samples for training an eye detector since they contain eyes with different shape, orientation and pupil localization. Experimental results show that our eye detector is a fast and robust detector. Furthermore, our method for coarse pupil localization can obtain not only high detection rate but also high localization speed.


Deep multi-view graph clustering network with weighting mechanism and collaborative training

Abstract: With the development of graph convolutional network (GCN), which is powerful in graph embedding learning meanwhile can capture node feature information, deep multi-view graph clustering methods based on graph autoencoder have emerged as a new stream. Although they achieve satisfactory performance, they still have the following weaknesses: (1) some of them model the weights for different views in the encoder part by using attention in the multi-view embedding fusion layer, but fail to consider the weighting in the decoder part to measure the contributions of different views to the reconstruction loss. (2) Most of them directly conduct clustering on the multi-view common embedding layer, but fail to guarantee the alignment of clustering results of different views. To this end, we propose a novel GCN-based deep multi-view graph clustering network with weighting mechanism and collaborative training (DMVGC). The model is composed of multiple view-specific graph encoders and a unified graph decoder. Besides the specially-designed attention module in the encoder part, we construct a reconstruction loss with adaptive weighting mechanism in the decoder part. Additionally, a collaborative self-training clustering objective is jointly conducted on each view-specific embedding layer and the common embedding layer, to make the embedding of each view clustering-friendly toward a common partition. Experiments on several datasets demonstrate the effectiveness of our model.


Multi-site solar irradiance forecasting based on adaptive spatiotemporal graph convolutional network

Abstract: Accurate solar irradiance forecasting with fine spatiotemporal correlations is essential for photovoltaic power generation. However, current spatiotemporal methods are unable to extract spatial features appropriately, leading to rough prediction results. Consequently, a deep graph neural network is proposed in this paper for multi-site solar irradiance forecasting. Self-adaptive adjacency matrices were developed to better capture the intrinsic influence between sites under different climate types at various time steps. Based on the adaptive graph convolution and long short-term memory network (AGCLSTM), the spatiotemporal features of each site were extracted to obtain prediction results for all the sites in the research area simultaneously. In the experiments conducted on the datasets of three climate types, the average root mean square error (RMSE), mean absolute error (MAE), and correlation coefficient (R) of the proposed model are observed to be in a range of 47.519–54.854 W/m2, 18.968–24.426 W/m2, and 0.9737–0.9889, respectively. Compared to the benchmark models, the average RMSE and MAE reduce by 1.31%–10.86% and 3.75%–18.57%, respectively. Moreover, the proposed method proves to be effective for scenes of solar irradiance fluctuations with the help of self-adaptive adjacency matrices, which enhances its generalization ability and prediction accuracy for one-hour-ahead solar irradiance forecasting.


Advanced strategies on update mechanism of tree-seed algorithm for function optimization and engineering design problems

Abstract: Tree-seed algorithm (TSA) is one of the meta-heuristic algorithms proposed recently. It has a simple but effective structure. However, for complex high-dimensional functions and constrained optimization problems, TSA has the defects of slow convergence rate and low optimization accuracy. To overcome these issues, an improved tree-seed algorithm (SATSA) based on Nelder-Mead simplex method is proposed. Firstly, appropriately increase the value of the control parameters that balance exploration and exploitation, thereby improving the local search ability of TSA, and introduce an adaptive stochastic component of Gaussian distribution in the seed generation formula of the local search stage. Then, set the maximum retention times of each tree, for trees that exceed the maximum retention times in continuous iterations, increase the number of seeds produced by this tree, then use a new equation based on the global optimal location to generate seeds, thereby speeding up the convergence of the algorithm. Finally, after all trees produce seeds, introduce the improvement strategy with Nelder-Mead simplex method into some poor quality solutions, so that the solution with poor quality is searched deeply in the neighborhood, speeding up the process of moving the overall solution to the optimal solution. Its convergence is proved by theoretical analysis, and certifies that the time complexity of SATSA is not increased compared to TSA. The simulation results of 6 advanced algorithms on CEC2017 test suite and 10 challenging engineering constrained optimization problems demonstrate that the three strategies proposed in this study are feasibility and effectiveness.


Class imbalance mitigation: A select-then-extract learning framework for emotion-cause pair extraction

Abstract: The class imbalance problem arises in the current end-to-end models for the emotion-cause pair extraction (ECPE) task, and a large number of negative clause pairs interfere model to depict the characteristics of emotion and cause. Most existing methods adopt a window-constrained strategy to limit the relative distance between candidate clauses to a smaller range to filter negative pairs. However, those methods ignore the semantic association between distant clauses, and using an artificial window size is imperfect due to the inherent ambiguity and delicacy of emotion. Inspired by the centrality principle of discourse, in this paper we propose a select-then-extract framework for the ECPE task, where the core clauses are first selected from the original document as candidate emotion and cause clauses, and then emotions, causes and emotion-cause pairs are jointly extracted from the candidate clauses. Specifically, our model includes two main components: core clause selector and emotion-cause pairs extractor. For the Core Clause Selector, we introduce the extractive document summarization (EDS) task and present a multi-granularity semantic awareness cooperative graph model (MGCOG) to extract core clauses from documents. Compared to the previous methods, the core clause selector is more effective for alleviating the category imbalance because the global causal cues and context can be captured by learning global keywords and inter-clause relationships, which determines more efficient candidate clauses. For Emotion-Cause Pairs Extractor, we put forward a multi-task learning model to jointly extract emotions, causes and emotion-cause pairs from the selected core clauses. Here, a multi-head attention is used to further model the relationship between candidate clauses, and a co-predictor is designed for assigning scores to all possible emotion-cause pairs. We further investigate the pipeline and the joint model under the select-then-extract framework, and show that the experimental results on benchmark datasets are consistently superior to the comparative baseline models. Extensive ablation experiments also verify the effectiveness of each component.


Realistic feature perception for face frontalization with dual-mode face transformation

Abstract: Despite face frontalization developing rapidly, limited image pairs and low image quality are still obstacles to face frontalization. Although single-view-based face frontalization does not have the constraints of image pairs, it reduces the exploration of unknown data. We alleviate the face distortion problem based on single-view face frontalization from two aspects. One is that we designed a dual-mode face transformation model for model training based on the loss of facial features from different angles. These two training modes cope with the question of face frontalization in different distortions. Specifically, we apply the 3D head model to the data transformation by fitting the 2D image to the 3D model. Rotating the 3D model at the designed angle to realize the face transformation. We judge the distortion extent with Euler Angle and produce the two training modes corresponding to the dual-mode face transformation. On the other hand, we construct a perceptual loss module to preserve the detailed information of the front view. This module combines content and identity loss to generate the photorealistic frontal image. In qualitative and quantitative experiments, we conduct experiments to illustrate the advantages of the proposed model on controlled and field datasets. Further, we apply full-reference and no-reference image quality assessment methods to estimate the quality of images generated by different face frontalization models.


Traffic Sign Recognition Using Optimized Federated Learning in Internet of Vehicles

Abstract: Traffic Sign Recognition (TSR) is vital for vehicle safety and navigation, especially in the era of autonomous cars. Internet of Vehicles (IoV) provide a promising infrastructure for vehicular networks due to their agility and interoperability. However, privacy concerns and network restrictions hinder the collection of massive data from distributed automotive sensors in IoV. To address these challenges, this paper proposes the application of Federated Learning (FL) and model sparsification to optimize TSR in autonomous vehicles. FL enables decentralized learning while preserving data privacy, and model sparsification significantly reduces communication costs. Furthermore, we incorporate the Adam optimizer for local training, ensuring efficient model optimization on each vehicle. Experimental results demonstrate the effectiveness of our approach, with improved TSR performance while mitigating privacy risks and enhancing communication efficiency. This research contributes to the advancement of TSR in IoV by introducing FL, model sparsification, and the use of the Adam optimizer for local training, facilitating efficient and privacy-preserving vehicular network learning.


Enhancing texture representation with deep tracing pattern encoding

Abstract: Texture representation is a challenging problem due to the complex underlying physics of texture as well as the variations caused by changes in viewpoint. Recent progress in texture analysis has been made by the power of convolutional neural networks (CNNs) in feature learning. However, most current methods aggregate the features from the last convolutional layer of the CNN to obtain a global feature vector, which fails to leverage shallow low-level visual cues and cross-layer feature patterns, limiting their performance. In this paper, we propose to trace the features generated along the convolutional layers via a histogram of local 3D invariant binary patterns, called deep tracing patterns. This leads to a highly discriminative yet robust global feature representation module. Building such a module into a CNN backbone, we develop an effective approach for texture recognition. Extensive experiments on six benchmark datasets show that the proposed approach provides a discriminative and robust texture descriptor, with state-of-the-art performance achieved.


Performance evaluation for multi-target tracking with temporal dimension specifics

Abstract: With the great development of Multi-Target Tracking (MTT) technologies, many MTT algorithms have been proposed with their own advantages and disadvantages. Due to the fact that requirements to MTT algorithms vary from the application scenarios, performance evaluation is significant to select an appropriate MTT algorithm for the specific application scenario. In this paper, we propose a performance evaluation method on the sets of trajectories with temporal dimension specifics to compare the estimated trajectories with the true trajectories. The proposed method evaluates the estimate results of an MTT algorithm in terms of tracking accuracy, continuity and clarity. Furthermore, its computation is based on a multi-dimensional assignment problem, which is formulated as a computable form using linear programming. To enhance the influence of recent estimated states of the trajectories in the evaluation, an attention function is used to reweight the trajectory errors at different time steps. Finally, simulation results show that the proposed performance evaluation method is able to evaluate many aspects of the MTT algorithms. These evaluations are worthy for selecting suitable MTT algorithms in different application scenarios.


Characteristics of students’ learning behavior preferences — an analysis of self-commentary data based on the LDA model

Abstract: How to better grasp students’ learning preferences in the environment of rapid development of engineering and science and technology so as to guide them to high-quality learning is one of the important research topics in the field of educational technology research today. In order to achieve this goal, this paper utilizes the LDA (Latent Dirichlet Allocation) model for text mining of the survey results on the basis of a survey on students’ self-perception evaluation. The results show that the LDA model is capable of extracting terms from text, fuzzy identifying groups of students at different levels and presenting potential logical relationships between the groups, and further analyzing the learning preferences of students at different levels for IT courses. Based on the student’s learning needs, this paper proposes recommendations for developing students’ learning effectiveness. The LDA method proposed in this paper is a feasible and effective method for assessing students’ learning dynamics as it generates cognitive content about students’ learning and allows for the timely discovery of students’ learning expectations and cutting-edge dynamics.


Shadow-aware dynamic convolution for shadow removal

Abstract: With a wide range of shadows in many collected images, shadow removal has aroused increasing attention since uncontaminated images are of vital importance for many computer vision tasks. Current methods consider the same convolution operations for both shadow and non-shadow regions while ignoring the large gap between the color mappings for the shadow region and the non-shadow region, leading to poor quality of reconstructed images and a heavy computation burden. To solve this problem, this paper introduces a novel plug-and-play Shadow-Aware Dynamic Convolution (SADC) module to decouple the interdependence between the shadow region and the non-shadow region. Inspired by the fact that the color mapping of the non-shadow region is easier to learn, our SADC processes the non-shadow region with a lightweight convolution module in a computationally cheap manner and recovers the shadow region with a more complicated convolution module to ensure the quality of image reconstruction. Given that the non-shadow region often contains more background color information, we further develop a novel intra-convolution distillation loss to strengthen the information flow from the non-shadow region to the shadow region. Extensive experiments on the ISTD and SRD datasets show our method achieves better performance in shadow removal over many state-of-the-art methods. Codes have been made available at https://github.com/xuyimin0926/SADC.


Image inpainting exploiting global prior refined weighted low-rank representation

Abstract: Low-rank and nonlocal self-similarity are important priors for image restoration. Based on nonlocal self-similarity assumption, similar patches are grouped into a matrix that is of low-rank or approximately low-rank. Traditional algorithms model low-rank prior of local group matrices (intra-group) and ignore the global inter-group relationship, which will result in suboptimal performance without considering global consistency. Due to overlapping of patches, groups are dependent, however, conventional methods process each group independently. To make full use of the intrinsic relationship among groups, we consider all groups simultaneously and propose a global prior refined weighted low-rank representation model for image inpainting. The local-groups and the aggregation of all groups are taken into account in the proposed model. By introducing auxiliary variable, we decouple the local–global model and optimize iteratively using the alternating direction method of multipliers. The proposed global refinement model significantly improves the performance of local low-rank model. A new strategy for grouping similar patches is also proposed by dividing the neighborhood of a target patch into multiple subregions and searching for a given number of similar patches within each subregion. The proposed method is applied to various tasks (line inpainting, destriping, and depth map completion) and obtains promising performance.


Underwater image enhancement utilizing adaptive color correction and model conversion for dehazing

Abstract: Underwater imaging is typically affected by absorption and scattering, which can lead to color distortion and image blurring. However, no universal color constancy algorithm for correcting underwater images exists due to the wide variation in underwater scenes. Furthermore, methods based on learning to improve underwater image quality often suffer from a lack of ground truth, which can compromise the validity and authenticity of restored images. In this study, we propose an adaptive underwater image enhancement technique that corrects image color and reduces haze using a valid dataset with ground truth. Specifically, we first use hue channel statistics from underwater images to build a dataset of color-corrected images from different underwater scenes. We use this dataset to train an Unet-like network for adaptive color correction. After color correction, underwater images often exhibit characteristics similar to hazy terrestrial images. We refer to this phenomenon as “model conversion”. The hazy terrestrial images have corresponding ground truth. Therefore, we train a Transformer-like network with hazy terrestrial image datasets to remove haze in underwater images. Our method is more robust for different underwater scenes and elegantly solves the problem of lacking ground truth. A series of experiments demonstrate that our method achieves superior performance compared to state-of-the-art methods in terms of both visual quality and quantitative metrics.


AdaptiveStereo: Depth estimation from adaptive structured light

Abstract: Recovering depth with active stereo methods has become an important approach to three-dimensional perception. However, when the properties of the measurement scene change, projecting predesigned structured light can cause improper exposure and defocus blur on some object surfaces. To address these problems, we propose an active stereo depth perception method called AdaptiveStereo, based on adaptive structured light (ASL). The core idea is to use prior depth information to generate optimal structured light for different measurement scenes, ensuring even illumination of the object's surface and thereby improving depth perception results. To this end, firstly, a novel ASL encoding scheme based on speckle pattern is designed. Then, we construct an adaptive structured light generation model (ASL-GM) to automatically generate the optimal structured light. Finally, depth perception is realized by using the active stereo matching network with adaptive guidance (AGS-Net). Compared with mainstream depth perception methods, the evaluation results show that our method has higher accuracy, and can obtain better depth perception results.