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In this paper, a distributed fixed-time composite learning control problem is addressed for nonlinear multiagent systems (MASs) subject to intermittent actuator faults. First, a distributed estimator is constructed for followers that are unable to communicate directly with the leader. Then, instead of using the traditional adaptive neural network (NN) algorithm, a predictor-based composite learning technique is proposed, which incorporates the prediction error into the NN update law to enhance the estimation accuracy of the unknown nonlinearity. Furthermore, an adaptive fault-tolerant control compensation mechanism is developed for intermittent faults that may occur indefinitely and frequently. To guarantee that all signals of the closed-loop system are bounded in fixed time, a nonsingular fixed-time fault-tolerant controller in the form of quadratic function is established. Finally, simulation results confirm the effectiveness of the presented algorithm. • This paper presents a singularity-free fixed-time NN algorithm for nonlinear MASs, and a composite learning algorithm is established to improve the approximation accuracy of nonlinear functions by introducing a prediction error into NN update law. • For followers without access to the leader, a local estimator is utilized to estimate the leader information. Therefore, the present control method avoids the emergence of coupling terms between agents during the controller design. • This paper considers intermittent actuator faults that may occur indefinitely and frequently, posing significant challenges. [ABSTRACT FROM AUTHOR]

In recent years, multi-agent reinforcement learning techniques have been widely used and evolved in the field of artificial intelligence. However, traditional reinforcement learning methods have limitations such as long training time, large sample data requirements, and highly delayed rewards. Therefore, this paper systematically and specifically studies the MARL algorithm. Firstly, this paper uses Citespace software to visually analyze the existing literature on multi-agent reinforcement learning and briefly indicates the research hotspots and key research directions in this field. Secondly, the applications of traditional reinforcement learning algorithms under two task objects, namely single-agent and multi-agent systems, are described in detail. Then, the paper highlights the diverse applications, challenges, and corresponding solutions of MARL algorithmic techniques in the field of MAS. Finally, the paper points out future research directions based on the existing limitations of the algorithm. Through this paper, readers will gain a systematic and in-depth understanding of MARL algorithms and how they can be utilized to better address the various challenges posed by MAS. [ABSTRACT FROM AUTHOR]

Label distribution learning represents the relevance of labels to samples using description degree, which can provide richer semantic information, thus finding wider applications. Exploiting label correlations is an effective approach to narrow down the hypothesis space of label distribution learning models. In existing works that utilize low-rank assumptions or label linear dependence to mine correlations, it is assumed that a label can be linearly expressed by other labels. However, this assumption can only be satisfied when there are linear dependency relationships between labels, thus the label correlation obtained by such methods is subject to certain distortion. To address this issue, this paper assumes that labels can be linearly represented by the same set of bases. The correlation between labels is represented by sharing common bases. Specifically, the paper employs matrix factorization to extract bases that can be used to represent all labels. And then designs a label distribution learning algorithm based on the property of sharing the same set of bases of the ground truth label distribution and predict label distribution. The effectiveness of the algorithm is verified through experimental validation. Generally speaking, the algorithm presented in this paper achieves optimal performance at 73.15% of the cases, with the best average ranking. In the two-tailed t -test, the algorithm in this paper exhibits statistical superiority compared to all comparison algorithms. [ABSTRACT FROM AUTHOR]

Modern machine learning algorithms aim to extract fine-grained information from data to provide accurate predictions, which often conflicts with the goal of privacy protection. This paper addresses the practical and theoretical importance of developing privacy-preserving machine learning algorithms that ensure good performance while preserving privacy. In this paper, we focus on the privacy and utility (measured by excess risk bounds) performances of differentially private stochastic gradient descent (SGD) algorithms in the setting of stochastic convex optimization. Specifically, we examine the pointwise problem in the low-noise setting for which we derive sharper excess risk bounds for the differentially private SGD algorithm. In the pairwise learning setting, we propose a simple differentially private SGD algorithm based on gradient perturbation. Furthermore, we develop novel utility bounds for the proposed algorithm, proving that it achieves optimal excess risk rates even for non-smooth losses. Notably, we establish fast learning rates for privacy-preserving pairwise learning under the low-noise condition, which is the first of its kind. [ABSTRACT FROM AUTHOR]

Low computational cost artificial intelligence (AI) models are vital in promoting the accessibility of real-time medical services in underdeveloped areas. The recent Once-For-All (OFA) network (without retraining) can directly produce a set of sub-network designs with Progressive Shrinking (PS) algorithm; however, the training resource and time inefficiency downfalls are apparent in this method. In this paper, we propose a new OFA training algorithm, namely the Progressive Expansion (ProX) to train the medical image analysis model. It is a reversed paradigm to PS, where technically we train the OFA network from the minimum configuration and gradually expand the training to support larger configurations. Empirical results showed that the proposed paradigm could reduce training time up to 68%; while still being able to produce sub-networks that have either similar or better accuracy compared to those trained with OFA-PS on ROCT (classification), BRATS and Hippocampus (3D-segmentation) public medical datasets. The code implementation for this paper is accessible at: https://github.com/shin-wl/ProX-OFA. [ABSTRACT FROM AUTHOR]

In the real world, the sources of text often transcend the boundaries of generative and natural domains, which introduces challenges for existing linguistic steganalysis methods. The typical problem arises from the sample selection bias caused by training solely on a single-source domain, rendering the model incapable of inferencing across the entire generative-natural (GN) space. Moreover, there exists the problem of overlooking the sensitive discrepancies between generative text and natural text, which hampers model fitting. In this paper, we model steganalysis in a brand-new perspective by employing multi-task learning to build the main task and auxiliary tasks in the cross GN domain. The proposed Cross Generative-Natural Domain Multi-task Model (CG-NDMM) can concurrently address the two aforementioned issues through i) modeling steganalysis across the entire GN space, incorporating two auxiliary tasks alongside a main task, and ii) utilizing a feature representation transfer learning strategy to harmonize two sub-networks. Furthermore, we employ diverse steganography algorithms to construct the datasets, which comprise four types of texts (generative-cover, generative-steganographic, natural-cover, and natural-steganographic) derived from two public datasets, Movie and Twitter. The experiments on these datasets demonstrate the effectiveness of the proposed approach, showcasing its substantially superior performance over the comparative baseline methods. [Display omitted] • A cross generative-natural domain multi-task model is proposed for steganalysis. • Transfer learning captures features distinguishing generative text from natural ones. • Multi-task learning reduces sample bias, boosts cross-domain steganalysis performance. [ABSTRACT FROM AUTHOR]

In this paper, the distributed Nash equilibrium seeking problem of multi-cluster games with time-varying local cost functions and local strategy set constraints is considered. Agents are divided into different clusters, and each cluster can be viewed as a virtual noncooperative player competing with others through a directed graph with a row-stochastic adjacency matrix. Agents in a cluster are the actual decision makers whose goal is to cooperatively minimize the cluster's time-varying cost function through a directed graph with a column-stochastic adjacency matrix. In this scenario, a distributed learning algorithm based on the consensus method and the gradient-tracking technique is proposed to seek the Nash equilibrium of the considered online multi-cluster game. Moreover, it can be theoretically proved that sublinearly bounded dynamic regrets can be guaranteed by properly choosing decreasing stepsizes when the path length accumulation and the gradient length accumulation increase sublinearly. Finally, theoretical results are verified by numerical simulations. [ABSTRACT FROM AUTHOR]

This paper investigates the specific properties of Explainable Artificial Intelligence (xAI), particularly when implemented in AI/ML models across high-stakes sectors, in this case cybersecurity. The authors execute a comprehensive systematic review of xAI properties, various evaluation metrics, and existing frameworks to assess their utility and relevance. Subsequently, the experimental sections evaluate selected xAI techniques against these metrics, delivering key insights into their practical utility and effectiveness. The findings highlight that the proliferation of metrics enhances the understanding of xAI systems but simultaneously exposes challenges such as metric duplication, inefficacy, and confusion. These issues underscore the pressing need for standardized evaluation frameworks to streamline their application and strengthen their effectiveness, thereby improving the overall utility of xAI in critical domains. • Bridging xAI theory and practice. • Systematic review of xAI metrics and frameworks. • Experimental evaluation of various xAI explanations. • The results show many metrics are ine2ective. • The abundance of metrics has pros and cons. [ABSTRACT FROM AUTHOR]

Meta-learning has been introduced in the recommendation domain, and a possible direction to extend graph-based meta-learning is how to exploit higher-order information between nodes. The current studies primarily rely on pre-embedding methods to utilize user attributes, inadvertently overlooking the crucial co-occurrence patterns among users' features. This oversight hinders the discovery of implicit connections between users. Furthermore, in scenarios of infrequent interactions, the reliance on initial edge information constrains connections between nodes in the same category. This constraint compromises the update capability of node embeddings, leading to reduced recommendation accuracy. In this paper, a meta-learning recommendation method with a dynamic node clustering knowledge graph (DCKG) is proposed. By introducing user attribute nodes and a triple-gated attention networks, this approach facilitates connections between users based on attribute relationships and enables the balancing of information across various pathways. Additionally, the integration of a dynamic aggregation module frees nodes of the same category from initial connection constraints, fostering more direct connections and further augmenting the propagation capability of higher-order information. The experimental results show that DCKG achieves the excellent results in the cold-start recommendation. DCKG can extend the use of higher-order features in the graph by direct connection. [ABSTRACT FROM AUTHOR]

The classification of imbalanced data remains one of the most significant topics in contemporary data analysis. Existing classification algorithms tend to favor majority classes, leading to false predictions and difficulties in addressing class overlap or label noise. These challenges are particularly evident in multiclass settings, where the mutual imbalance relationships among classes become more complex. Despite this, the vast majority of research in this field has concentrated on binary problems, while the more difficult multiclass problems are relatively underexplored. In this paper, we propose a novel data-sampling technique, a Multiclass Neighborhood Repartition-based Oversampling (MC-NRO) algorithm. The innovation of this method lies in it considers local data characteristics of each class to constrain the oversampled neighborhood. MC-NRO calculates the mutual potential of different classes to precisely optimize the subregions for generating new instances. By selecting different repartition neighborhoods to meet the needs of specific domain, it can detect outliers and label noise, expand the decision boundary of minority class, and avoid class overlap through data cleaning. The experimental results demonstrate that MC-NRO outperforms other advanced oversampling strategies, ranking first on average across the three evaluation metrics, and exhibits robustness, especially in datasets with high noise levels. More importantly, MC-NRO is highly versatile and can be flexibly applied to various classifiers, and is particularly suitable for processing naturally complex (i.e., not affected by noise) datasets. [ABSTRACT FROM AUTHOR]

This paper focuses on Multi-Agent Reinforcement Learning (MARL) in non-cooperative stochastic games, particularly addressing the challenge of task completion characterized by non-Markovian reward functions. We employ Reward Machines (RMs) to incorporate high-level task knowledge. Firstly, we introduce Q -learning with R eward M achines for S tochastic G ames (QRM-SG), where RMs are predefined and available to agents. QRM-SG learns each agent's best-response policy at Nash equilibrium by defining the Q-function in augmented state space that integrates the stochastic game and RM states. The Lemke-Howson method is utilized to compute the best-response policies for the stage game defined by the current Q-functions at each time step. Subsequently, we explore a more challenging scenario where RMs are unavailable and propose M ulti- A gent R einforcement learning with C oncurrent H igh-level knowledge inference (MARCH). MARCH uses automata learning to learn RMs iteratively and combines this process with QRM-SG for learning the best-response policies. The RL episodes where the obtained rewards are inconsistent with the rewards from the current RMs trigger the inference of new RMs. We prove QRM-SG and MARCH converge to the best-response policies under certain conditions. Two scenarios are conducted to demonstrate the superior performance of QRM-SG and MARCH compared to baseline methods. • We introduce RMs to address the challenge of non-Markovian reward functions in an SG. • We develop QRM-SG to enable agents to complete complex tasks in a non-cooperative SG. • We propose MARCH to jointly learn RMs and policies in a decentralized manner. • QRM-SG and MARCH converge to the best-response policies under certain conditions. • Two scenarios are conducted to evaluate the performance of QRM-SG and MARCH. [ABSTRACT FROM AUTHOR]

Artificial intelligence models encounter significant challenges due to their black-box nature, particularly in safety-critical domains such as healthcare, finance, and autonomous vehicles. Explainable Artificial Intelligence (XAI) addresses these challenges by providing explanations for how these models make decisions and predictions, ensuring transparency, accountability, and fairness. Existing studies have examined the fundamental concepts of XAI, its general principles, and the scope of XAI techniques. However, there remains a gap in the literature as there are no comprehensive reviews that delve into the detailed mathematical representations, design methodologies of XAI models, and other associated aspects. This paper provides a comprehensive literature review encompassing common terminologies and definitions, the need for XAI, beneficiaries of XAI, a taxonomy of XAI methods, and the application of XAI methods in different application areas. The survey is aimed at XAI researchers, XAI practitioners, AI model developers, and XAI beneficiaries who are interested in enhancing the trustworthiness, transparency, accountability, and fairness of their AI models. [ABSTRACT FROM AUTHOR]

Green artificial intelligence (AI) is more environmentally friendly and inclusive than conventional AI, as it not only produces accurate results without increasing the computational cost but also ensures that any researcher with a laptop can perform high-quality research without the need for costly cloud servers. This paper discusses green AI as a pivotal approach to enhancing the environmental sustainability of AI systems. Described are AI solutions for eco-friendly practices in other fields (green-by AI), strategies for designing energy-efficient machine learning (ML) algorithms and models (green-in AI), and tools for accurately measuring and optimizing energy consumption. Also examined are the role of regulations in promoting green AI and future directions for sustainable ML. Underscored is the importance of aligning AI practices with environmental considerations, fostering a more eco-conscious and energy-efficient future for AI systems. • Green AI emphasizes sustainable and energy-efficient AI and ML models. • Strategies for designing energy-efficient systems are explored (green-in AI). • Also explored are AI approaches to enhancing eco-friendly practices (green-by AI). • Several options exist for green AI innovations in algorithm and hardware optimization. • Future trends are discussed. [ABSTRACT FROM AUTHOR]

The sparsity and redundancy of high-dimensional data poses challenges during processing. Dimensionality reduction is a commonly used approach, which helps to reduce data redundancy and noise, lower the complexity of learning algorithms, and improve classification accuracy. Typically, directly determining the intrinsic dimensionality of a dataset is challenging. Many of the present dimensionality reduction techniques suffer from pre-set target dimensions without considering the specific dataset features. To address this problem, a novel dimensionality reduction method based on flow model, which is called adaptive flow encoder (AFE), is proposed in this paper. Initially, the flow model is employed to achieve feature transformation and project the data onto an equip-dimensional feature space. Subsequently, a gating layer is utilized for feature selection. By configuring the gating layer parameters to be learnable, the model gains the ability to adaptively select features. To assess the efficacy of the proposed approach, the model's ability to preserve data characteristics is first qualitatively evaluated through visual inspection by projecting the data onto a two-dimensional space. Subsequently, five standard datasets are employed and compared against six traditional dimensionality reduction techniques to ascertain the impact on downstream classification tasks under the adaptive learning of intrinsic feature dimensions by the model. Moreover, the impact of key parameters, including the initialization scheme of the gate layer, amplification factor, and dimension factor, on the test results is examined. [ABSTRACT FROM AUTHOR]

Reconstructing the three-dimensional structure of a scene is a classic and fundamental problem in computer vision, but it has been revolutionized by recent advancements in deep machine learning. In this paper, we survey this rich and growing area. We divide the work into four main threads: 3D reconstruction from two calibrated images from a binocular camera; 3D reconstruction from more than two images taken by the same camera or more than two calibrated cameras; object-focused 3D reconstruction with relaxed camera calibration; and SLAM-based techniques. We summarize each approach along four salient dimensions: algorithmic and deep network characteristics, output representation, datasets, and quantitative comparisons among different methods. We also discuss key challenges and future directions. [ABSTRACT FROM AUTHOR]

Multi-view clustering (MVC) is a prevailing clustering method that exploits consistency and complementarity among views to achieve satisfactory performance. The premise of MVC is that the samples of each view are mapped, that is, the same sample is placed in the same position among different views. However, multi-view data collected from the real world would also be unmapped, and thus conventional MVC methods are facing challenges. To address this problem, in our paper, we propose a novel aligned multi-view clustering (A-MVC) method for unmapped data. Specifically, the Calinski–Harabasz index is first employed to find the optimal view, and then the samples in other views are aligned to the samples in the optimal view with the help of the alignment matrix so that the unmapped data are converted into mapped ones. In addition, A-MVC absorbs the advantages of conventional multi-view clustering and employs both weighted tensor nuclear norm (TNN) and graph learning algorithms, which simultaneously learn the global representation and capture the local information. Finally, we integrate the alignment algorithm with a low-rank constraint based on weighted TNN and graph constraints into a unified framework. Extensive experimental results on certain unmapped multi-view datasets show that A-MVC outperforms other state-of-the-art methods. The codes and datasets are available at https://github.com/bingly/A-MVC. [ABSTRACT FROM AUTHOR]

Diabetic Retinopathy (DR) is considered one of the significant concerns worldwide, primarily due to its impact on causing vision loss among most people with diabetes. The severity of DR is typically comprehended manually by ophthalmologists from fundus photography-based retina images. This paper deals with an automated understanding of the severity stages of DR. In the literature, researchers have focused on this automation using traditional machine learning-based algorithms and convolutional architectures. However, the past works hardly focused on essential parts of the retinal image to improve the model performance. In this study, we adopt and fine-tune transformer-based learning models to capture the crucial features of retinal images for a more nuanced understanding of DR severity. Additionally, we explore the effectiveness of image transformers to infer the degree of DR severity from fundus photographs. For experiments, we utilized the publicly available APTOS-2019 blindness detection dataset, where the performances of the transformer-based models were quite encouraging. • Computational assessment of diabetic retinopathy (DR) via fundus image analysis. • Utilizing transformer networks for early detection and severity assessment of DR. • Ensembling diverse image transformers for automated DR severity analysis. • Comprehensive experiments on APTOS-2019, comparing with state-of-the-art methods. [ABSTRACT FROM AUTHOR]

As an important branch of emerging artificial intelligence algorithms, multi-agent reinforcement learning (MARL) has shown strong performance in collaborative environments. It can utilize multiple agents to find the optimal set of strategies for solving sequential decision problem through trial-and-error. One of the main challenges facing multi-agent system is the non-stationarity problem, which brings poor convergence and seriously affects its performance. Clustering is a commonly used unsupervised analytical method in machine learning, which aims to group samples with similar internal properties into the same cluster. In this paper, we propose a MARL clustering algorithm based on silhouette coefficient (SC-MARLC), and use the trial-and-error strategy to find the best cluster groups. In SC-MARLC, we establish a mapping relationship between multi-agent and samples, construct a novel clustering model based on MARL, and design a good clustering subset structure based on the sample silhouette coefficient. The designed structure is helpful for multi-agent system to solve the non-stationary problem. Finally, we compare the performance of SC-MARLC with 11 existing clustering algorithms on fifteen public datasets. The results show that the new clustering algorithm performs best on ten datasets. [Display omitted] [ABSTRACT FROM AUTHOR]

Link prediction is a crucial aspect of graph machine learning, with applications as diverse as disease prediction, social network recommendations, and drug discovery. It involves the prediction of potential new links between nodes within a network. Despite its importance, current models for link prediction exhibit notable limitations. Graph Convolutional Networks have shown high efficiency in link prediction across various datasets. However, they face significant challenges when applied to short-path networks and ego networks, resulting in poor performance. This issue represents a critical area of concern that our work seeks to address. This paper introduces the Node Centrality and Similarity-based Parameterised Model (NCSM), a novel method for link prediction tasks. NCSM uniquely integrates node centrality and similarity measures as edge features in a customised Graph Neural Network (GNN) layer, effectively leveraging the topological information of large networks. This model represents the first parameterised GNN-based link prediction model that considers topological information. The proposed model was evaluated on five benchmark graph datasets, each comprising thousands of nodes and edges. Experimental results highlight NCSM's superiority over existing state-of-the-art models like Graph Convolutional Networks and Variational Graph Autoencoder, as it outperforms them across various metrics and datasets. This exceptional performance can be attributed to NCSM's innovative integration of node centrality, similarity measures, and its efficient use of topological information. • Introduced Node Centrality and Similarity based Parameterised Model (NCSM) for link prediction. • NCSM uses node centrality and similarity as edge features in a custom Graph Neural Network. • Evaluated NCSM on five benchmark datasets, surpassing models like Graph Convolutional Networks and Variational Graph Autoencoder. • NCSM excels by uniquely combining node measures and effectively utilising network topology. [ABSTRACT FROM AUTHOR]

In the last decade it became increasingly apparent the inability of technical metrics such as accuracy, sustainability, and non-regressiveness to well characterize the behavior of intelligent systems. In fact, they are nowadays requested to meet also ethical requirements such as explainability, fairness, robustness, and privacy increasing our trust in their use in the wild. Of course often technical and ethical metrics are in tension between each other but the final goal is to be able to develop a new generation of more responsible and trustworthy machine learning. In this paper, we focus our attention on machine learning algorithms and associated predictive models, questioning for the first time, from a theoretical perspective, if it is possible to simultaneously guarantee their performance in terms of both technical and ethical metrics towards machine learning algorithms that we can trust. In particular, we will investigate for the first time both theory and practice of deterministic and randomized algorithms and associated predictive models showing the advantages and disadvantages of the different approaches. For this purpose we will leverage the most recent advances coming from the statistical learning theory: Complexity-Based Methods, Distribution Stability, PAC-Bayes, and Differential Privacy. Results will show that it is possible to develop consistent algorithms which generate predictive models with guarantees on multiple trustworthiness metrics. • AI is nowadays requested to optimize both technical and ethical metrics. • Focus on ML algorithms and associated models (both deterministic and randomized). • We prove that it is possible to develop consistent algorithms and models. • We bound generalization in terms of both technical and ethical metrics. • We leverage the most recent advances coming from the statistical learning theory. [ABSTRACT FROM AUTHOR]

Nonnegative matrix factorization (NMF) is an effective technique to extract the underlying low-dimensional structure of data by utilizing its parts-based representation, which has been widely used in feature extraction and machine learning. However, NMF is an unsupervised learning algorithm without utilizing the discriminative prior information. In this paper, we put forward a new class-driven NMF with manifold regularization (MCDNMF) algorithm, which incorporates both the local manifold regularization and the label information of data into the NMF model. Specifically, MCDNMF not only encodes the local geometrical structure of data space by using the manifold regularization, but also takes the available label information by introducing the class-driven constraint. This class-driven constraint forces the new representations of data points to be more similar within the same class while different between other classes. Therefore, the discriminative abilities of clustering are greatly boosted. Experimental results on several datasets validate the effectiveness of proposed MCDNMF in comparison with the other state-of-the-art methods. [ABSTRACT FROM AUTHOR]

Deep learning (DL) has been shown to be very effective for many application domains of machine learning (ML), including image classification, voice recognition, natural language processing, and bioinformatics. The success of DL techniques is directly related to the availability of large amounts of training data. However, in many cases, the data are sensitive to the users and should be protected to preserve the privacy. Privacy-preserving deep learning (PPDL) has thus become a very active research field to ensure the training process and use of DL models are productive without exposing or leaking information about the data. This paper aims to provide a comprehensive survey of PPDL. We concentrate on the risks that affect data privacy in DL and conduct a detailed investigation into the models that ensure privacy. Finally, we propose a set of evaluation criteria, detailing the advantages and disadvantages of the solutions. Based on the analyzed strengths and weaknesses, the paper has highlighted some important research problems and application cases that have not been studied and these point to certain open research directions. [ABSTRACT FROM AUTHOR]

Federated Learning (FL) has emerged as a powerful paradigm for training Machine Learning (ML), particularly Deep Learning (DL) models on multiple devices or servers while maintaining data localized at owners' sites. Without centralizing data, FL holds promise for scenarios where data integrity, privacy and security and are critical. However, this decentralized training process also opens up new avenues for opponents to launch unique attacks, where it has been becoming an urgent need to understand the vulnerabilities and corresponding defense mechanisms from a learning algorithm perspective. This review paper takes a comprehensive look at malicious attacks against FL, categorizing them from new perspectives on attack origins and targets, and providing insights into their methodology and impact. In this survey, we focus on threat models targeting the learning process of FL systems. Based on the source and target of the attack, we categorize existing threat models into four types, Data to Model (D2M), Model to Data (M2D), Model to Model (M2M) and composite attacks. For each attack type, we discuss the defense strategies proposed, highlighting their effectiveness, assumptions and potential areas for improvement. Defense strategies have evolved from using a singular metric to excluding malicious clients, to employing a multifaceted approach examining client models at various phases. In this survey paper, our research indicates that the to-learn data, the learning gradients, and the learned model at different stages all can be manipulated to initiate malicious attacks that range from undermining model performance, reconstructing private local data, and to inserting backdoors. We have also seen these threat are becoming more insidious. While earlier studies typically amplified malicious gradients, recent endeavors subtly alter the least significant weights in local models to bypass defense measures. This literature review provides a holistic understanding of the current FL threat landscape and highlights the importance of developing robust, efficient, and privacy-preserving defenses to ensure the safe and trusted adoption of FL in real-world applications. The categorized bibliography can be found at: https://github.com/Rand2AI/Awesome-Vulnerability-of-Federated-Learning. [ABSTRACT FROM AUTHOR]

Every day, enormous amounts of biomedical texts discussing various biomedical topics are produced. Revealing strong semantic connections hidden in those unstructured data is essential for many interesting applications such as knowledge base development for the biomedical domain as well as drug repurposing and drug–disease associations. Literature based discovery (LBD) is a well-known paradigm that refers to the issues of finding new hidden knowledge in scientific literature by connecting pieces of semantically-related information belonging to independent documents. This challenging research area has been extensively investigated by the research community and different proposals adopting natural language processing, text mining, machine learning and recently deep learning have been developed. This paper exploits a very focused task, it surveys a collection of research papers published in the recent years that have adopted Deep Learning for literature based discovery as an effective technique to discover new relationships between existing knowledge in biomedical domain. The study provides an analysis of the key characteristics of each work surveyed, including the Literature based discovery application area, the deep learning method used, the type of analyzed data, and the results obtained. Recognizing the significance of Pre-trained Language Models (PLMs), another primary aim of this paper is to offer an extensive overview of the latest developments in pre-trained language models within the field of biomedicine. This focus will primarily be on how they are applied to downstream tasks associated with Literature-Based Discovery in the biomedical domain. Additionally, the survey highlights the key drawbacks of the current state-of-the-art proposals, as well as the challenges that require further study by the research community. [ABSTRACT FROM AUTHOR]

The target net method has been the foundation of deep reinforcement learning since Deepmind first proposed it in 2015. Almost all the current popular reinforcement learning algorithms include target net. However, while the slowly updated target network improves the stability of the algorithm, it also reduces the performance of the algorithm. In this paper, the authors design a novel triple-network algorithm(TPN). TPN combines the temporal-difference(TD) algorithm and policy gradient(PG) theorem. Using three networks to estimate the state value(v), action value (q) , and policy(π). These networks have no primary or secondary distinction but are trained synchronously and influence each other. The author found that through this TPN architecture, the convergence and stability of the algorithm can be greatly improved without increasing the amount of calculation. Although it is only a basic framework at present. The calculation process of TPN is simple and easy to implement. Experiments prove that the convergence speed and stability of TPN in discrete cases are better than PPO. • Proposed a new deep reinforcement learning algorithm that does not rely on target networks. • Presented the complete derivation process of the TPN algorithm. • Verified the effectiveness of proposed algorithm through experiments. [ABSTRACT FROM AUTHOR]

The Wasserstein distance in the optimal transport (OT) model is being widely used in machine learning applications due to its mathematical and geometric properties. Since the entropy regularized OT is a convex problem, and for its large-scale problems, many algorithms have been proposed. Existing methods mainly adopt iterative random projection techniques to approximate the Wasserstein distance in the OT model. In this paper, we employ the entropic domain decomposition algorithm with mini-batch learning to calculate the entropy regularized OT problem and investigate the stability of this algorithm. The algorithm performs on different cells of the domain instead of using the projection technique and it is based on a mini-batch loss function. The corresponding solution in each iteration is derived from the dual problem of entropy regularized OT on each decomposed cell. Once the solutions to the dual problem on all decomposed cells are obtained, the corresponding transport plan in each iteration can be obtained. We show that the transport plan computed by its dual variables is admissible, and we also give the sub-gradient approximation result. In addition, we exploit the statistical concentration result of the subsampled mini-batch Wasserstein distance on decomposed cells. Finally, the numerical experiments validate that the proposed algorithm can save computational time further. [ABSTRACT FROM AUTHOR]

In this paper, an enhanced structural developmental neural network with information saturation (ESDNNIS) is proposed for continual unsupervised learning. It improves SDNNIS in the following respects: (1) it makes a distinction between the developmental stages of neurons to better regulate the updating of neurons; (2) it adopts the forgetting mechanism to control the network size; (3) it changes the way coverage domain parameter is initialized and updated to divide clusters more accurately; and (4) it adds a parent–child relationship update mechanism to provide better robustness to sample input order. ESDNNIS inherits the unsupervised incremental learning and class segmentation capabilities of SDNNIS, and achieves better class incremental clustering for more complex datasets while using fewer neurons than SDNNIS. The experimental results show that the accuracy of clustering results of ESDNNIS is improved by 10.94% on average compared with SDNNIS, while the number of generated neurons is reduced by 71.93% on average. [ABSTRACT FROM AUTHOR]

Gradient-based algorithms are still popularly used for training radial basis function neural network (RBFNN). However, these algorithms may lead to the vanishing gradient (saddle point or local minimum) problem, which is one of the common problems that limit learning performance. To cope with this, a hybrid hyperplane gradient learning algorithm (HHGLA) is proposed to improve the learning performance of the RBFNN in this paper. First, a hyperplane gradient (HPG), based on a hyperspace constructed by a solution population (SP), is introduced. Thus, the search process can cross the surface of the cost function to avoid the appearance of vanishing gradient. Second, an adaptive learning rate is designed to restrict the search process into this hyperspace. Then, during the learning process, the hyperspace is constantly contracted to approximate the global optimal solution. Third, the convergence property of HHGLA-based RBFNN is thoroughly analyzed to ensure its application success. Finally, empirical comparisons of the proposed HHGLA-RBFNN are given to illustrate its superiority. The simulation results show the feasibility of HHGLA-RBFNN of accuracy. [ABSTRACT FROM AUTHOR]

Federated learning, a privacy-preserving collaborative machine learning paradigm, has led to the proposal of various incentive mechanisms to encourage active participation of data owners. However, most of the existing mechanisms focused on the monopsony market scenario, where only one server-side entity (buyer) is involved. In real-world scenarios, multiple server parties may express simultaneous interest in the data of a client (seller), leading to a non-monopoly market. This paper aims to bridge this gap by introducing the concept of incentivizing federated learning in a non-monopoly market and presents a non-monopoly federated learning incentive mechanism, coined as NmFLI. NmFLI employs a double-auction mechanism to implement federated learning incentives and utilizes the Vickery–Clarke–Groves (VCG) mechanism to ensure client trustworthiness. Additionally, NmFLI devises a method for measuring data quality by calculating the value of clients based on their historical performance, which effectively balances accuracy and computational complexity. We demonstrate that NmFLI possesses properties such as individual rationality and strategy-proofness. Experimental results indicate that NmFLI can effectively incentivize federated learning and achieve higher accuracy than baseline models across various scenarios. For example, when the objectives of various tasks overlap, NmFLI outperforms the best baseline by 3.09% with imbalanced client data while maintaining the same data size. Moreover, NmFLI surpasses the best baseline by 6.12% with different amounts of client data. [ABSTRACT FROM AUTHOR]

The expensive optimization problem, widespread in real-world applications, poses great challenges to traditional evolutionary algorithms (EAs) due to its costly evaluations. A lot of investigations have proved that it is a practical way to incorporate surrogate models into EAs to reduce the number of time-consuming evaluations. Although various types of surrogate models from the community of machine learning, such as regression models that approximate the fitness values of candidate solutions or classification models that predict candidate solutions' category, have been widely applied separately, none of them consistently outperforms the other. Considering the intrinsic consistency of alleviating computational burden to improve the optimization efficiency, this paper introduces a two-layer architecture to integrate regression and classification models and synergize global and local evolution for high-dimensional expensive many-objective optimization problem (EMaOP). To implement this idea, the Kriging model based on incremental learning is utilized to explore the potential promising space. Further, multi local support vector machine (SVM) classifiers assisted improved differential evolution is run by turn with the global search to accelerate convergence. Accordingly, a novel surrogate-assisted EA, named Classification- and Regression-assisted evolutionary algorithm (CR-SAEA), is proposed on this basis. Experimental studies on several benchmark functions with up to 11 objectives and 200 dimensions confirm the effectiveness of the proposed algorithm and its competitiveness against state-of-the-art algorithms. [ABSTRACT FROM AUTHOR]

Uncertainty estimation is a critical component of building safe and reliable machine learning models. Accurate estimation of uncertainties is essential for identifying and mitigating potential risks and ensuring that machine learning systems operate reliably in real-world scenarios. Various approaches, such as ensemble and Bayesian neural networks have been developed by sampling probability predictions from submodels, which is computationally expensive. At present, these techniques are incapable of precisely delineating the boundary separating in-distribution (ID) and out-of-distribution (OOD) data. To fill up this research gap, this paper presents a normalizing flow based framework to directly predict parameters of prior distributions over the probability with a neural network, the proposed model is able to effectively differentiate between ID and OOD data in regression problems. The posterior distributions learned by the model precisely represent uncertainties for OOD data based solely on ID data, without the need for OOD data during training. This approach has shown promising results in a number of applications, including image depth estimation and image adversarial attacks. [ABSTRACT FROM AUTHOR]

Effective animal intelligent monitoring is of great value in terms of ecological protection and endangered specie conservation. At present, computer vision technologies have shed light on animal intelligent monitoring. Especially, numerous deep learning-based models and methods have been developed to address various challenges, and have made substantial strides in this field. However, there are still several problems to be solved and related areas to be mined, such as exploring new strategies to enhance the robustness and generalization ability of models, designing novel models for complex environments, and establishing large-scale publicly available animal datasets for performance verification of models. Therefore, we comprehensively elaborated and analyzed existing works on animal intelligent monitoring based on advanced information science technologies, so as to provide useful information assistance for relevant researchers. In this paper, we focus on three primary task fields: precise animal localization, tracking and individual identification. Specifically, we elucidate the definition and significance of each monitoring task, and summarize the baseline models for addressing different problems. We provide a specific analysis of strategies and prototypes of the models and methods employed in each tasks following by the technical progression from traditional machine learning to deep learning. In addition, we make a comparison and analysis of the relevant methods, summarize their similarities and differences between them, and point out the advantages and disadvantages of these methods. Finally, we present several unresolved challenges and problems in animal intelligent monitoring and provide potential research directions in the future. We expect that our review can serve as reference and guidance for related research fields. [ABSTRACT FROM AUTHOR]

The eight papers included in this special issue represent a selection of extended contributions presented at the 17th International Conference on Soft Computing Models in Industrial and Environmental Applications, SOCO 2022 held in Salamanca, Spain, September 6th-8th, 2022, and organized by the BISITE group at University of Salamanca. SOCO 2022 international conference represents a collection or set of computational techniques in machine learning, computer science and some engineering disciplines which investigate, simulate, and analyse very complex issues and phenomena. This special issue is aimed at practitioners, researchers, and postgraduate students who are engaged in developing and applying advanced intelligent systems principles to solve real-world problems in the mentioned fields. [ABSTRACT FROM AUTHOR]

Addressing the reproducibility crisis in artificial intelligence through the validation of reported experimental results is a challenging task. It necessitates either the reimplementation of techniques or a meticulous assessment of papers for deviations from the scientific method and best statistical practices. To facilitate the validation of reported results, we have developed numerical techniques capable of identifying inconsistencies between reported performance scores and various experimental setups in machine learning problems, including binary/multiclass classification and regression. These consistency tests are integrated into the open-source package mlscorecheck , which also provides specific test bundles designed to detect systematically recurring flaws in various fields, such as retina image processing and synthetic minority oversampling. [ABSTRACT FROM AUTHOR]

Neural networks and deep learning algorithms are designed to function similarly to biological synaptic structures. However, classical deep learning algorithms fail to fully capture the need for continuous learning; this has led to the advent of incremental learning. Incremental learning adds new challenges that are handled differently by modern state-of-the-art approaches. Some of these include: utilization of network memory as additional knowledge increases the size of the network, open-set recognition to be able to identify unrecognized information, and efficient knowledge distillation as most incremental learning algorithms are prone to catastrophic forgetting of previously learned knowledge. Recent advancements achieve incremental learning through a multitude of methods. Most methods are characterized by augmenting the normal algorithm of neural network training by both directly modifying the neural network structure and by adding additional learning steps. This paper analyzes and provides a comprehensive survey of existing methods and various techniques used for incremental learning. A novel categorization of the methods is also introduced based on recent trends of the state-of-the-art solutions. The study focuses on methods that provide incremental learning success as well as discusses emerging patterns in new research. [ABSTRACT FROM AUTHOR]

A-to-I RNA editing is a long-known driving factor to the progression of hepatocellular carcinoma (HCC); however, its importance is often neglected in HCC subtyping and the modeling of prognosis, partially due to the high dimensional nature of the editing data. In this paper, we first obtain a comprehensive A-to-I RNA editing profile for HCC, among which two editing sites, IGFBP7 I387M (chr4:57110120) and SUMF2 A98G (chr7:56078974), are identified as having the driving function potential. Then, we exploit the clinical-related RNA editing profile in combination with the gene expressions to develop a new prognostic model for HCC. To preserve the inner structure of this editing profile in a latent space that has a much lower dimension, we employ variational autoencoder (VAE), an unsupervised learning neural network applied for the first time to compress the RNA editing profile. Empowered by VAE, we are able to cluster the HCC patients efficiently according to their editing profile, among which a group of patients with immune dysregulation and enrichment in cell proliferation and cancer-related pathways are identified. Based on the editing-related subtyping, we develop a prognostic model that consists of an easy-computing risk score and an adaptively trained threshold. Validations using three independent cohorts (LIHC, LIRI, and GSE14520) confirm that the new model is robust, sensitive, and specific. Furthermore, it is more accurate in prediction than six state-of-the-art competitors. The model is also found applicable to 18 more cancers besides HCC, which suggests a strong ability in generalization. To facilitate clinical usage, we develop a nomogram, drug targets, prognosis-associated genes, and relevant pathways are also identified, which pave the way for upcoming studies on HCC's molecular mechanism, therapeutic targets, and many others. • A New prognostic modeling approach incorporating the A-to-I RNA editing information into classical framework featured by genes. • A prognostic model for HCC using the approach validated in 3 cohorts and outperforming 6 state-of-the-art competitors. • Two editing sites, IGFBP7 I387M (chr4:57110120) and SUMF2 A98G (chr7:56078974), located and found associated with HCC. [ABSTRACT FROM AUTHOR]

This paper proposes a novel recurrent context layered radial basis function neural network (RCLRBFNN) for the identification of nonlinear dynamical systems. The proposed model consists of an additional context layer in which the nodes represent the unit-delayed outputs of the hidden layer radial centers. These delayed outputs undergo a nonlinear transformation by applying a tangent hyperbolic function. These transformed signals connect to the output layer neuron through the adjustable context layered weights. To tune the parameters of the proposed model the update equations are derived using the dynamic back-propagation algorithm. Further, an adaptive learning rate scheme is proposed to improve the performance of the learning algorithm. In the simulation experiment, a total of two examples are considered to test the efficacy and performance of the proposed model. The performance comparison is made with the conventional structure of the radial basis function neural network (RBFNN), Jordan Recurrent neural network (JRNN), and the feed-forward neural network (FFNN) (which is nothing but a single-layered multi-layered perceptron). Both the disturbance signal as well as system's uncertainty scenarios are considered to test the robustness shown by the proposed model. The results showed that the proposed model has delivered a better identification accuracy as compared to the other neural models. [ABSTRACT FROM AUTHOR]

Accurate prediction of rate of penetration is a prerequisite for optimization of drilling parameters. However, characteristics such as multiple drilling conditions, inconsistency in data length and various drilling variables can lead to inaccurate prediction of rate of penetration in actual drilling process. Therefore, it is important to use appropriate methods to predict rate of penetration for the above characteristics. This paper proposes an online prediction method of rate of penetration based on drilling conditions identification. First, data preprocessing and correlation analysis are employed to handle various drilling variables to obtain optimal model inputs. Then, dynamic time warping method is used to solve inconsistency in data length. Further, for multiple drilling conditions, the fuzzy c-means and dynamic time warping are combined to identify drilling conditions. Next, different extreme learning machine models optimized by genetic algorithm are built to predict rate of penetration for different drilling conditions. Finally, the results involving actual data illustrate that the prediction error of the proposed hybrid method of fuzzy c-means, dynamic time warping, extreme learning machine and genetic algorithm meets the requirements. The proposed hybrid method outperforms the comparative methods in four performance metrics, which verify the rationality and necessity of considering drilling conditions when predicting rate of penetration. [ABSTRACT FROM AUTHOR]

The seven papers included in this special issue represent a selection of extended contributions presented at the 16th International Conference on Soft Computing Models in Industrial and Environmental Applications, SOCO 2021, held in Bilbao, Spain, September 22nd-24th, 2021, and organized by the BISITE group and the University of Deusto. The SOCO 2021 international conference represents a collection or set of computational techniques in machine learning, computer science and some engineering disciplines that investigate, simulate, and analyse very complex issues and phenomena. This special issue is aimed at practitioners, researchers, and postgraduate students who are engaged in developing and applying advanced intelligent systems principles to solve real-world problems in the mentioned fields. [ABSTRACT FROM AUTHOR]

Super-resolution aims to enhance the quality of a low-resolution image to create a high-resolution one. Remarkable advances are witnessed in this field using machine learning techniques. This paper presents a super-resolution method based on generative adversarial networks (GAN) with quantum feature enhancement. The proposed framework uses a feature enhancement layer inspired by the quantum superposition principle. The layer was added to the state-of-the art super-resolution GAN (SRGAN) original model to enhance its performance. The model was trained and evaluated using two publicly available high-resolution aerial images datasets taken by an unmanned aerial vehicle. A set of statistically significant experiments are reported to show its performance. The structural similarity index metric (SSIM), t-distributed stochastic neighbor embedding (t-SNE) and peak signal-to-noise ratio (PSNR) are adopted to evaluate the performance of this proposal against SRGAN model. Results show that this proposal outperforms SRGAN in term of image reconstruction quality by 8% in similarity. [ABSTRACT FROM AUTHOR]

User interest reflects user preference which plays an important role in commercial decision-making. Learning and predicting user interest has attracted significant attention in recent years, however, user interest will change under uncertain environments as time passes, called user interest drift. This may adversely impact the accuracy of machine learning model prediction and lead to a delay in decision-making. How to detect and adapt to user interest drift in streaming data is an important problem which needs to be addressed. In this paper, we propose a novel method to detect user interest drift, called the topic-based user interest drift detection method (T-IDDM), which can recognize the severity of user interest drift. Then, a self-adaptive ensemble (SA-Ensemble) method with an adaptive weighted voting strategy is proposed to deal with user interest drift and reduce the time decay of the voting process. Next, a dynamic voting strategies selection process is proposed and applied to improve model robustness. Finally, an application study of user interest drift learning is presented to verify the proposed method. Twelve sequential online reviews datasets are collected and tested for the experiment. A comparison of our method with state-of-the-art benchmark methods shows its efficiency. • A topic-based user interest drift detection method (T-IDDM) is introduced for changing identification. • A self-adaptive ensemble (SA-Ensemble) method is proposed to enhance learning performance. • A dynamic voting strategies selection mechanism is given to maintain robustness. • An application of the proposed method for user interest drift learning is adopted. [ABSTRACT FROM AUTHOR]

Deep Q-Networks algorithm (DQN) was the first reinforcement learning algorithm using deep neural network to successfully surpass human level performance in a number of Atari learning environments. However, divergent and unstable behaviour have been long standing issues in DQNs. The unstable behaviour is often characterised by overestimation in the Q -values, commonly referred to as the overestimation bias. To address the overestimation bias and the divergent behaviour, a number of heuristic extensions have been proposed. Notably, multi-step updates have been shown to drastically reduce unstable behaviour while improving agent's training performance. However, agents are often highly sensitive to the selection of the multi-step update horizon (n), and our empirical experiments show that a poorly chosen static value for n can in many cases lead to worse performance than single-step DQN. Inspired by the success of n -step DQN and the effects that multi-step updates have on overestimation bias, this paper proposes a new algorithm that we call 'Elastic Step DQN' (ES-DQN) to alleviate overestimation bias in DQNs. ES-DQN dynamically varies the step size horizon in multi-step updates based on the similarity between states visited. Our empirical evaluation shows that ES-DQN out-performs n -step with fixed n updates, Double DQN and Average DQN in several OpenAI Gym environments while at the same time alleviating the overestimation bias. [ABSTRACT FROM AUTHOR]

The standard machine learning assumption that training and test data are drawn from the same probability distribution does not hold in many real-world applications due to the inability to reproduce testing conditions at training time. Existing unsupervised domain adaption (UDA) methods address this problem by learning a domain-invariant feature space that performs well on available source domain(s) (labeled training data) and the specific target domain (unlabeled test data). In contrast, instead of simply adapting to domains, this paper aims for an approach that learns to adapt effectively to new unlabeled domains. To do so, we leverage meta-learning to optimize a neural network such that an unlabeled adaptation of its parameters to any domain would yield a good generalization on this latter. The experimental evaluation shows that the proposed approach outperforms standard approaches even when a small amount of unlabeled test data is used for adaptation, demonstrating the benefit of meta-learning prior knowledge from various domains to solve UDA problems. [ABSTRACT FROM AUTHOR]

In recent years, a constant and fast information growing has characterized digital applications in the majority of real-life scenarios. Thus, a new information asset, namely Big Data, has been defined and lead to different challenges, mainly related to data storage, management and analysis. Focusing on the last challenge, several Big Data analytics techniques have been developed, based on Machine Learning and Deep Learning paradigms. When dealing with Big Data, traditional approaches often take a lot of time to produce even a single predictive model, due to the extremely high demand of computational resources. The design of approaches specifically oriented to Big Data is required to overcome these computational issues. Most solutions rely on the deployment of Big Data analytics infrastructures on a cluster of machines and/or on parallelization techniques. When deployment and parallelization apply to Machine Learning and Deep Learning, we can refer to the terms Distributed Machine Learning and Distributed Deep Learning, respectively. We here discuss the main principles and features of Distributed Machine Learning and Distributed Deep Learning frameworks. The main contribution of this work is a survey of solutions proposed in the literature, through the investigation of selected features and capabilities. In particular, the survey provides a comparative analysis according to the following classification criteria: implemented parallelization technique, supporting device, supported architecture, implemented communication mode, working mode, and class of algorithms. The paper also gives an overview of the most commonly used criteria and metrics for the performance evaluation of analyzed frameworks; finally, some emerging but promising optimization techniques are reviewed apart from our classification. • Big Data analytics leads to challenges related to data management and analysis. • An analysis of the related solutions proposed in the literature is required. • The analysis is focused on Distributed Machine Learning and Deep Learning. • Overview of framework performance evaluation criteria with optimization techniques. [ABSTRACT FROM AUTHOR]

Recently, various normalization layers have been proposed to stabilize the training of deep neural networks. Among them, group normalization is a generalization of layer normalization and instance normalization by allowing a degree of freedom in the number of groups it uses. However, to determine the optimal number of groups, trial-and-error-based hyperparameter tuning is required, and such experiments are time-consuming. In this study, we discuss a reasonable method for setting the number of groups. First, we find that the number of groups influences the gradient behavior of the group normalization layer. Based on this observation, we derive the ideal number of groups, which calibrates the gradient scale to facilitate gradient descent optimization. This paper is the first to propose an optimal number of groups that is theoretically grounded, architecture-aware, and can provide a proper value in a layer-wise manner for all layers. The proposed method exhibited improved performance over existing methods in numerous neural network architectures, tasks, and datasets. • We propose a method to determine the number of groups of group normalization. • A theoretical analysis of group normalization with activation function is provided. • The proposed method is validated against various practical problems. [ABSTRACT FROM AUTHOR]

Continual lifelong learning is an machine learning framework inspired by human learning, where learners are trained to continuously acquire new knowledge in a sequential manner. However, the non-stationary nature of streaming training data poses a significant challenge known as catastrophic forgetting, which refers to the rapid forgetting of previously learned knowledge when new tasks are introduced. While some approaches, such as experience replay (ER), have been proposed to mitigate this issue, their performance remains limited, particularly in the class-incremental scenario which is considered natural and highly challenging. In this paper, we present a novel algorithm, called adaptive-experience replay (AdaER), to address the challenge of continual lifelong learning. AdaER consists of two stages: memory replay and memory update. In the memory replay stage, AdaER introduces a contextually-cued memory recall (C-CMR) strategy, which selectively replays memories that are most conflicting with the current input data in terms of both data and task. Additionally, AdaER incorporates an entropy-balanced reservoir sampling (E-BRS) strategy to enhance the performance of the memory buffer by maximizing information entropy. To evaluate the effectiveness of AdaER, we conduct experiments on established supervised continual lifelong learning benchmarks, specifically focusing on class-incremental learning scenarios. The results demonstrate that AdaER outperforms existing continual lifelong learning baselines, highlighting its efficacy in mitigating catastrophic forgetting and improving learning performance. [ABSTRACT FROM AUTHOR]

Conventional machine learning methodologies require the centralization of data for model training, which may be infeasible in situations where data sharing limitations are imposed due to concerns such as privacy and gradient protection. The Federated Learning (FL) framework enables the collaborative learning of a shared model without necessitating the centralization or sharing of data among the data proprietors. Nonetheless, in this paper, we demonstrate that the generalization capability of the joint model is suboptimal for Non-Independent and Non-Identically Distributed (Non-IID) data, particularly when employing the Federated Averaging (FedAvg) strategy as a result of the weight divergence phenomenon. Consequently, we present a novel boosting algorithm for FL to address both the generalization and gradient leakage challenges, as well as to facilitate accelerated convergence in gradient-based optimization. Furthermore, we introduce a secure gradient sharing protocol that incorporates Homomorphic Encryption (HE) and Differential Privacy (DP) to safeguard against gradient leakage attacks. Our empirical evaluation demonstrates that the proposed Federated Boosting (FedBoosting) technique yields significant enhancements in both prediction accuracy and computational efficiency in the visual text recognition task on publicly available benchmarks. [ABSTRACT FROM AUTHOR]

The rapid adoption of Industry 4.0 has seen Information Technology (IT) networks increasingly merged with Operational Technology (OT) networks, which have traditionally been isolated on air-gapped and fully trusted networks. This increased attack surface has resulted in compromises of Cyber–Physical Systems (CPS) with significant economic and life safety consequences. This paper proposes a hybrid model of anomaly detection of security threats to CPS by blending the signature-based and threshold-based Intrusion Detection Systems (IDS) commonly used in IT networks, with a Machine Learning (ML) model designed to detect behaviour-based anomalies in OT networks. This hybrid model achieves more rapid detection of known threats through signature-based and threshold-based detection strategies, and more accurate detection of unknown threats via behaviour-based anomaly detection using ML algorithms. • Anomaly detection in Cyber–Physical Systems. • Internet of Things (IoT) Security. • One-class machine learning. [ABSTRACT FROM AUTHOR]

Official gazettes are documents published by governments to publicize their actions, spanning long periods of time and making an important transparency mechanism. These documents have information on laws, contracts, and bidding processes, as well as on civil servants and their careers in public service. Automatic information extraction of these documents may contribute to public transparency, with two tasks being especially useful: the classification of the different segments of these documents, the so called acts; and the Named Entity Recognition (NER) within the acts. The variety of official gazettes and their patterns brings up the necessity of constructing different tools for specific gazettes. In this paper, we propose DODFMiner, a command-line interface tool to classify acts and extract named entities from the Official Gazette of the Federal District. The tool follows a 3-step approach: the pre-processing of the input data; text classification using rule-based systems with regular expressions; and NER with Machine Learning algorithms. It allows users to input JSON files and receive CSV as output, providing information that allows users to track government procurements through years, contracts duration and total amount, among others. We also propose a set of experiments to support the choice of models included in the tool, covering the classification and NER steps. Text classification achieved a mean F1-score of 0.778, while to the NER, we compared 3 different architectures, CRF with a mean F1-score of 0.851, CNN-biLSTM-CRF with 0.787 and CNN-CNN-LSTM with 0.841. [ABSTRACT FROM AUTHOR]

A novel hybrid neural network based learning control method is proposed to improve trajectory tracking accuracy for complex robot manipulators in this paper. Firstly, a hybrid neural network is presented to improve the model accuracy and data efficiency, which is integrated by the Differential Newton-Euler Algorithm (DiffNEA) and Radial Basis Function Neural Network (RBFNN). In this hybrid neural network, the DiffNEA takes in charge of modeling the known rigid dynamics, while RBFNN takes in charge of capturing the unmodeled phenomena and external disturbances. Secondly, an incremental design method is proposed to determine optimal structure and parameters of the hybrid neural network. Thirdly, an adaptive learning controller based on the aforementioned hybrid neural network is designed to further reject the effects of unmodeled dynamics and external disturbances on trajectory tacking performance. Finally, experimental results are presented to validate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]