Reviewerly/exHarmony huggingface dataset:
FaciesViT: Vision transformer for an improved core lithofacies prediction

Lithofacies classification is a fundamental step to perform depositional and reservoir characterizations in the subsurface. However, such a classification is often hindered by limited data availability and biased and time-consuming analysis. Recent work has demonstrated the potential of image-based supervised deep learning analysis, specifically convolutional neural networks (CNN), to optimize lithofacies classification and interpretation using core images. While most works have used transfer learning to overcome limited datasets and simultaneously yield a high-accuracy prediction. This method raises some serious concerns regarding how the CNN model learns and makes a prediction as the model was originally trained with entirely different datasets. Here, we proposed an alternative approach by adopting a vision transformer model, known as FaciesViT , to mitigate this issue and provide improved lithofacies prediction. We also experimented with various CNN architectures as the baseline models and two different datasets to compare and evaluate the performance of our proposed model. The experimental results show that the proposed models significantly outperform the established CNN architecture models for both datasets and in all cases, achieving an f1 score and weighted average in all tested metrics of 95%. For the first time, this study highlights the application of the Vision Transformer model to a geological dataset. Our findings show that the FaciesViT model has several advantages over conventional CNN models, including (i) no hyperparameter fine-tuning and exhaustive data augmentation required to match the accuracy of CNN models; (ii) it can work with limited datasets; and (iii) it can better generalize the classification to a new, unseen dataset. Our study shows that the application of the Vision transformer could further optimize image recognition and classification in the geosciences and mitigate some of the issues related to the generalizability and the explainability of deep learning models. Furthermore, the implementation of our proposed FaciesViT model has been shown to improve the overall performance and reproducibility of image-based core lithofacies classification which is significant for subsurface reservoir characterization in different basins worldwide.
Estimation of the success probability of a malicious attacker on blockchain-based edge network

Modeling highly accurate cyber-attacks on blockchain-based edge networks may be almost impossible in real-world circumstances due to unanticipated adversary (malicious) behavior. In this study, we propose a novel, distributed blockchain-based security architecture that today’s industrial edge-enabled IoT systems may use to strengthen their defences against cyberattacks. We develop a probabilistic model to estimate the success probability of a malicious attacker on blockchain-based edge network by considering (i) hardware-level attack, (ii) network-level attack (IoT, Edge), (iii) software-level attack, wallet, smart contract, and (iv) blockchain network-level attack. We analyze the proposed attack model for sixteen different cyberattacks: False Data Injection, Sybil, DDoS, Identity Spoofing, Side-Channel, Botnet, Backdoor Trojan, Targeted Code Injection, Social Engineering, Phishing, Sinkhole, Man-in-the-middle, SQL Injection, Consensus, Eclipse, and Block Mining. Our model considers scenarios where private keys are stolen, lost, or forgotten by certain nodes. To determine the probability that a malicious attacker will be successful, we develop a simulation environment (a blockchain-based edge network with 200 total nodes, which generates 47,540 samples). We then estimate the success probability of a malicious attacker based on the blockchain resiliency (fault-tolerance) provided by the consensus algorithm, attack types, attack location, and the network size for various scenarios. Our results demonstrate that blockchain-based edge networks are more vulnerable to malicious attacks based on: (i) cyber-attack types (90.96% for Botnet and Backdoor Trojan attacks higher than for other attacks, such as DDoS, SQL Injection and Sybil); (ii) attack location (90.18% for software-level attacks higher than hardware, network, and blockchain network-level attacks); and (iii) consensus algorithm (68.85% for Byzantine fault tolerance, BFT, higher than the Proof-of-Work, PoW). The IoT network vulnerability factor, or exposure factor, of cyberattacks, depends on the strategic importance of the application to the attacker. Our results should be validated in real-world experiments with a large number of nodes.
TBNet: A Two-Stream Boundary-Aware Network for Generic Image Manipulation Localization

Abstract - Finding tampered regions in images is a common research topic in machine learning and computer vision. Although many image manipulation location algorithms have been proposed, most of them only focus on RGB images with different color spaces, and the frequency information that contains the potential tampering clues is often ignored. Moreover, among the manipulation operations, splicing and copy-move are two frequently used methods, but as their characteristics are quite different, specific methods have been individually designed for detecting the operations of either splicing or copy-move, and it is very difficult to widely apply these methods in practice. To solve these issues, in this work, a novel end-to-end two-stream boundary-aware network (abbreviated as TBNet) is proposed for generic image manipulation localization where the RGB stream, the frequency stream, and the boundary artifact location are explored in a unified framework. Specifically, we first design an adaptive frequency selection module (AFS) to adaptively select the appropriate frequency to mine inconsistent statistics and eliminate the interference of redundant statistics. Then, an adaptive cross-attention fusion module (ACF) is proposed to adaptively fuse the RGB feature and the frequency feature. Finally, the boundary artifact location network (BAL) is designed to locate the boundary artifacts for which the parameters are jointly updated by the outputs of the ACF, and its results are further fed into the decoder. Thus, the parameters of the RGB stream, the frequency stream, and the boundary artifact location network are jointly optimized, and their latent complementary relationships are fully mined. The results of the extensive experiments performed on six public benchmarks of the image manipulation localization task, namely, CASIA1.0, COVER, Carvalho, In-The-Wild, NIST-16, and IMD-2020, demonstrate that the proposed TBNet can substantially outperform state-of-the-art generic image manipulation localization methods in terms of MCC, F1, and AUC while maintaining robustness with respect to various attacks. Compared with DeepLabV3+ on the CASIA1.0, COVER, Carvalho, In-The-Wild, and NIST-16 datasets, the improvements in MCC/F1 reach 11&#x0025;/11.1&#x0025;, 8.2&#x0025;/10.3&#x0025;, 10.2&#x0025;/11.6&#x0025;, 8.9&#x0025;/6.2&#x0025;, and 13.3&#x0025;/16.0&#x0025;, respectively. Moreover, when IMD2020 is utilized, its AUC improvement can achieve 14.7&#x0025;.
Local Variational Quantum Compilation of Large-Scale Hamiltonian Dynamics

Implementing time evolution operators on quantum circuits is important for quantum simulation. However, the standard way, Trotterization, requires a huge numbers of gates to achieve desirable accuracy. Here, we propose a local variational quantum compilation (LVQC) algorithm, which allows to accurately and efficiently compile a time evolution operators on a large-scale quantum system by the optimization with smaller-size quantum systems. LVQC utilizes a subsystem cost function, which approximates the fidelity of the whole circuit, defined for each subsystem as large as approximate causal cones brought by the Lieb-Robinson (LR) bound. We rigorously derive its scaling property with respect to the subsystem size, and show that the optimization conducted on the subsystem size leads to the compilation of whole-system time evolution operators. As a result, LVQC runs with limited-size quantum computers or classical simulators that can handle such smaller quantum systems. For instance, finite-ranged and short-ranged interacting $L$-size systems can be compiled with $O(L^0)$- or $O(\log L)$-size quantum systems depending on observables of interest. Furthermore, since this formalism relies only on the LR bound, it can efficiently construct time evolution operators of various systems in generic dimension involving finite-, short-, and long-ranged interactions. We also numerically demonstrate the LVQC algorithm for one-dimensional systems. Employing classical simulation by time-evolving block decimation, we succeed in compressing the depth of a time evolution operators up to $40$ qubits by the compilation for $20$ qubits. LVQC not only provides classical protocols for designing large-scale quantum circuits, but also will shed light on applications of intermediate-scale quantum devices in implementing algorithms in larger-scale quantum devices.
Conditional dependence structure and risk spillovers between Bitcoin and fiat currencies

This paper investigates the extreme dependence and risk spillovers between Bitcoin and the currencies of the BRICS and G7 economies. We find time-varying dependence between Bitcoin and all currencies. Moreover, when analysing risk spillovers from Bitcoin to currencies, we find that Bitcoin exercises significant power over most currencies, with the South African rand and Brazilian real holding both the highest downside and upside risk before and during the COVID-19 pandemic period, respectively. When considering risk spillovers from currencies towards Bitcoin, the Japanese yen exhibits the highest downside spillovers. Importantly, we find asymmetric spillovers between extreme upward and downward movements.
HetVis: A Visual Analysis Approach for Identifying Data Heterogeneity in Horizontal Federated Learning

Horizontal federated learning (HFL) enables distributed clients to train a shared model and keep their data privacy. In training high-quality HFL models, the data heterogeneity among clients is one of the major concerns. However, due to the security issue and the complexity of deep learning models, it is challenging to investigate data heterogeneity across different clients. To address this issue, based on a requirement analysis we developed a visual analytics tool, HetVis, for participating clients to explore data heterogeneity. We identify data heterogeneity through comparing prediction behaviors of the global federated model and the stand-alone model trained with local data. Then, a context-aware clustering of the inconsistent records is done, to provide a summary of data heterogeneity. Combining with the proposed comparison techniques, we develop a novel set of visualizations to identify heterogeneity issues in HFL. We designed three case studies to introduce how HetVis can assist client analysts in understanding different types of heterogeneity issues. Expert reviews and a comparative study demonstrate the effectiveness of HetVis.
Robust image hashing for content identification through contrastive self-supervised learning

Content identification systems are an essential technology for many applications. These systems identify query multimedia items using a database of known identities. A hash-based system uses a perceptual hashing function that generates a hash value invariant against a set of expected manipulations in an image, later compared to perform identification. Usually, this set of manipulations is well-known, and the researcher creates the perceptual hashing function that best adapts to the set. However, a new manipulation may break the hashing function, requiring to create a new one, which may be costly and time-consuming. Therefore, we propose to let the hashing function learn an invariant feature space automatically. For this, we exploit the recent advances in self-supervised learning, where a model uses unlabeled data to generate a feature representation by solving a metric learning-based pretext task that enforces the robust image hashing properties for content identification systems. To achieve model transferability on unseen data, our pretext task enforces the feature vector invariance against the manipulation set, and through random sampling on the unlabeled training set, we present the model a wide variety of perceptual information to work on. As exhaustive experimentation shows, this method achieves excellent robustness against a comprehensive set of manipulations, even difficult ones such as horizontal flip and rotation, with excellent identification performance. Also, the trained model is highly discriminative against the presence of near-duplicate images. Furthermore, this method does not need re-training or fine-tuning on a new dataset to achieve the observed performance, indicating an excellent generalization capacity.
EB-BFT: An elastic batched BFT consensus protocol in blockchain

With the rapid increasing number of applications using blockchain, how to improve the throughput of business and reduce the latency of committing transaction on the blockchain have become important topics. This article proposes an elastic batched byzantine fault tolerance consensus protocol whose name is EB-BFT, which elastically changing consensus nodes participating in the consensus and scaling the number of transactions batching in the consensus based on volume of the transaction as well as the physical resources. The protocol EB-BFT first identifies low-performance nodes and suspends them from participating in consensus, so the number of consensus nodes is dynamically changed. After validate the legality of transactions sent by clients, the algorithm of dynamically scaling the number of batched transactions in consensus is proposed. Finally, a series of experiments are conducted to verify the effectiveness and efficiency of EB-BFT in terms of throughput and latency, and it proves when the upper limit of the latency of committing transactions is set at 15 s, the dealing speed of business can reach 20000 transactions per seconds, this results proves that this protocol will make the blockchain having better performance in larger throughput and shorter latency of processing transactions, which also proves that our method can handle transactions as well as traditional centralized system.
An overview of violence detection techniques: current challenges and future directions

The Big Video Data generated in today's smart cities has raised concerns from its purposeful usage perspective, where surveillance cameras, among many others are the most prominent resources to contribute to the huge volumes of data, making its automated analysis a difficult task in terms of computation and preciseness. Violence detection (VD), broadly plunging under action and activity recognition domain, is used to analyze Big Video data for anomalous actions incurred due to humans. The VD literature is traditionally based on manually engineered features, though advancements to deep learning based standalone models are developed for real-time VD analysis. This paper focuses on overview of deep sequence learning approaches along with localization strategies of the detected violence. This overview also dives into the initial image processing and machine learning-based VD literature and their possible advantages such as efficiency against the current complex models. Furthermore,the datasets are discussed, to provide an analysis of the current models, explaining their pros and cons with future directions in VD domain derived from an in-depth analysis of the previous methods.
Disentangling Decentralized Finance (DeFi) Compositions

We present a measurement study on compositions of Decentralized Finance (DeFi) protocols, which aim to disrupt traditional finance and offer services on top of distributed ledgers, such as Ethereum. Understanding DeFi compositions is of great importance, as they may impact the development of ecosystem interoperability, are increasingly integrated with web technologies, and may introduce risks through complexity. Starting from a dataset of 23 labeled DeFi protocols and 10,663,881 associated Ethereum accounts, we study the interactions of protocols and associated smart contracts. From a network perspective, we find that decentralized exchange (DEX) and lending protocol account nodes have high degree and centrality values, that interactions among protocol nodes primarily occur in a strongly connected component, and that known community detection methods cannot disentangle DeFi protocols. Therefore, we propose an algorithm to decompose a protocol call into a nested set of building blocks that may be part of other DeFi protocols. This allows us to untangle and study protocol compositions. With a ground truth dataset that we have collected, we can demonstrate the algorithm’s capability by finding that swaps are the most frequently used building blocks. As building blocks can be nested, that is, contained in each other, we provide visualizations of composition trees for deeper inspections. We also present a broad picture of DeFi compositions by extracting and flattening the entire nested building block structure across multiple DeFi protocols. Finally, to demonstrate the practicality of our approach, we present a case study that is inspired by the recent collapse of the UST stablecoin in the Terra ecosystem. Under the hypothetical assumption that the stablecoin USD Tether would experience a similar fate, we study which building blocks — and, thereby, DeFi protocols — would be affected. Overall, our results and methods contribute to a better understanding of a new family of financial products.
Interacting with a Chatbot-Based Advising System: Understanding the Effect of Chatbot Personality and User Gender on Behavior

Chatbots with personality have been shown to affect engagement and user subjective satisfaction. Yet, the design of most chatbots focuses on functionality and accuracy rather than an interpersonal communication style. Existing studies on personality-imbued chatbots have mostly assessed the effect of chatbot personality on user preference and satisfaction. However, the influence of chatbot personality on behavioral qualities, such as users’ trust, engagement, and perceived authenticity of the chatbots, is largely unexplored. To bridge this gap, this study contributes: (1) A detailed design of a personality-imbued chatbot used in academic advising. (2) Empirical findings of an experiment with students who interacted with three different versions of the chatbot. Each version, vetted by psychology experts, represents one of the three dominant traits, agreeableness, conscientiousness, and extraversion. The experiment focused on the effect of chatbot personality on trust, authenticity, engagement, and intention to use the chatbot. Furthermore, we assessed whether gender plays a role in students’ perception of the personality-imbued chatbots. Our findings show a positive impact of chatbot personality on perceived chatbot authenticity and intended engagement, while student gender does not play a significant role in the students’ perception of chatbots.
Towards Efficient Detection for Small Objects via Attention-Guided Detection Network and Data Augmentation

Small object detection has always been a difficult direction in the field of object detection, especially the detection of small objects in UAV aerial images. The images captured by UAVs have the characteristics of small objects and dense objects. In order to solve these two problems, this paper improves the performance of object detection from the aspects of data and network structure. In terms of data, the data augmentation strategy and image pyramid mechanism are mainly used. The data augmentation strategy adopts the method of image division, which can greatly increase the number of small objects, making it easier for the algorithm to be fully trained during the training process. Since the object is denser, the image pyramid mechanism is used. During the training process, the divided images are up-sampled into three different sizes, and then sent to three different detectors respectively. Finally, the detection results of the three detectors are fused to obtain the final detection results. The small object itself has few pixels and few features. In order to improve the detection performance, it is necessary to use context. This paper adds attention mechanism to the yolov5 network structure, while adding a detection head to the underlying feature map to make the network structure pay more attention to small objects. By using data augmentation and improved network structure, the detection performance of small objects can be significantly improved. The experiment in this paper is carried out on the Visdrone2019 dataset and DOTA dataset. Through experimental verification, our proposed method can significantly improve the performance of small object detection.
Facial Expression Spotting Based on Optical Flow Features

The purpose of micro expression (ME) and macro expression (MaE) spotting task is to locate the onset and offset frames of MaE and ME clips. Compared with MaEs, MEs are shorter in duration and lower in intensity, which makes MEs harder to be spotted. In this paper, we propose an efficient pipeline based on optical flow features to spot MEs and MaEs. We crop and align the faces and select the eyebrows area, nose area, and mouth area as our regions of interest to exclude the interference of extraneous factors on the face expression representation. Then, we extract the optical flow in these regions and enhance the features of the expressions in the optical flow with low-pass filter and EMD method. Finally, the sliding window method is used to locate the peaks of optical flow features and get the intervals containing MEs or MaEs. We evaluate the performance of our method on the MEGC2022-TestSet including 10 long videos from SAMM and CAS(ME)3 and achieve the first place in the MEGC2022 Challenge. The results prove the effectiveness of our method.
FCL-GAN: A Lightweight and Real-Time Baseline for Unsupervised Blind Image Deblurring

Blind image deblurring (BID) remains a challenging and significant task. Benefiting from the strong fitting ability of deep learning, paired data-driven supervised BID methods have obtained great progress. However, paired data are usually synthesized by hand, and the realistic blurs are more complex than synthetic ones, which makes the supervised methods inept at modeling realistic blurs and hinders real-world applications. As such, unsupervised deep BID methods without paired data offer certain advantages, but current methods still suffer from some drawbacks, e.g., bulky model size, long inference time, and strict image resolution and domain requirements. In this paper, we propose a lightweight and real-time unsupervised BID baseline, termed Frequency-domain Contrastive Loss Constrained Lightweight CycleGAN (shortly, FCL-GAN), with attractive properties, i.e., no image domain limitation, no image resolution limitation, 25x lighter than SOTA, and 5x faster than SOTA. To guarantee the lightweight property and performance superiority, two new collaboration units called lightweight domain conversion unit (LDCU) and parameter-free frequency-domain contrastive unit (PFCU) are designed. LDCU mainly implements inter-domain conversion in lightweight manner. PFCU further explores the similarity measure, external difference and internal connection between the blurred domain and sharp domain images in frequency domain, without involving extra parameters. Extensive experiments on several image datasets demonstrate the effectiveness of our FCL-GAN in terms of performance, model size and inference time.