Reviewerly/exHarmony huggingface dataset:
Tseitin or not Tseitin? The Impact of CNF Transformations on Feature-Model Analyses

Feature modeling is widely used to systematically model features of variant-rich software systems and their dependencies. By translating feature models into propositional formulas and analyzing them with solvers, a wide range of automated analyses across all phases of the software development process become possible. Most solvers only accept formulas in conjunctive normal form (CNF), so an additional transformation of feature models is often necessary. However, it is unclear whether this transformation has a noticeable impact on analyses. In this paper, we compare three transformations (i.e., distributive, Tseitin, and Plaisted-Greenbaum) for bringing feature-model formulas into CNF. We analyze which transformation can be used to correctly perform feature-model analyses and evaluate three CNF transformation tools (i.e., FeatureIDE, KConfigReader, and Z3) on a corpus of 22 real-world feature models. Our empirical evaluation illustrates that some CNF transformations do not scale to complex feature models or even lead to wrong results for model-counting analyses. Further, the choice of the CNF transformation can substantially influence the performance of subsequent analyses.
TreeCen: Building Tree Graph for Scalable Semantic Code Clone Detection

Code clone detection is an important research problem that has attracted wide attention in software engineering. Many methods have been proposed for detecting code clone, among which text-based and token-based approaches are scalable but lack consideration of code semantics, thus resulting in the inability to detect semantic code clones. Methods based on intermediate representations of codes can solve the problem of semantic code clone detection. However, graph-based methods are not practicable due to code compilation, and existing tree-based approaches are limited by the scale of trees for scalable code clone detection.
DeepPerform: An Efficient Approach for Performance Testing of Resource-Constrained Neural Networks

Today, an increasing number of Adaptive Deep Neural Networks (AdNNs) are being used on resource-constrained embedded devices. We observe that, similar to traditional software, redundant computation exists in AdNNs, resulting in considerable performance degradation. The performance degradation is dependent on the input and is referred to as input-dependent performance bottlenecks (IDPBs). To ensure an AdNN satisfies the performance requirements of resource-constrained applications, it is essential to conduct performance testing to detect IDPBs in the AdNN. Existing neural network testing methods are primarily concerned with correctness testing, which does not involve performance testing. To fill this gap, we propose DeepPerform, a scalable approach to generate test samples to detect the IDPBs in AdNNs. We first demonstrate how the problem of generating performance test samples detecting IDPBs can be formulated as an optimization problem. Following that, we demonstrate how DeepPerform efficiently handles the optimization problem by learning and estimating the distribution of AdNNs' computational consumption. We evaluate DeepPerform on three widely used datasets against five popular AdNN models. The results show that DeepPerform generates test samples that cause more severe performance degradation (FLOPs: increase up to 552%). Furthermore, DeepPerform is substantially more efficient than the baseline methods in generating test inputs (runtime overhead: only 6–10 milliseconds).
RFA-Net: Residual feature attention network for fine-grained image inpainting

Although most existing methods using Generative Adversarial Networks (GAN) generally produce plausible results, there is a significant amount of artifacts and less-than-ideal restoration of textures when large regions are missing or the background of missing regions is complex. To address this issue, in this paper, we propose a novel texture-aware backbone net named RFA-Net for finer texture image inpainting. Compared to conventional encoder–decoder methods, our main contribution is proposing a novel RFA-Net adopt a non-pooling residual CNN structure with three novel modules, which retains texture features from shallow layers and adaptively learn the importance of certain channels and locations of features that may potentially benefit image inpainting. In addition, we propose a hybrid loss optimization (HLO) module to enable the generator to focus on the semantic and texture details of the inpainted contents. Experimental results demonstrate that our RFA-Net is able to recover texture details and ground-truth consistent images, and outperforms the state-of-the-art methods both in terms of image quality and quantitative metrics. Our source code and data are available online at https://github.com/Jamie-61/RFA-Net-Inpainting.
FPGA image encryption-steganography using a novel chaotic system with line equilibria

The wide dissemination of images makes its protection problems urgent. Chaos theory is widely applied since it provides better solutions to image protection. This paper introduces a novel chaotic system that has line equilibrium points. Chaotic signals generated by chaotic systems are used in encryption and steganography to enhance security. Besides, the scrambling-diffusion encryption system is combined with the least significant bit (LSB)-pixel value differencing (PVD) steganography algorithm. The proposed algorithm process is reversible and the extracted image is lossless. And the whole system is designed and implemented on a field programmable gate array (FPGA), which improves the embedding efficiency and achieves high throughput while ensuring good image quality.
Deep Learning and Embedding Based Latent Factor Model for Collaborative Recommender Systems

A collaborative recommender system based on a latent factor model has achieved significant success in the field of personalized recommender systems. However, the latent factor model suffers from sparsity problems. It is also limited in its ability to extract non-linear data features, resulting in poor recommendation performance. Inspired by the success of deep learning in different application areas, we incorporate deep learning into our proposed method to overcome the above problems. In this paper, we propose a dual deep learning and embedding-based latent factor model that considers dense user and item feature vectors. The model combines the existing deep learning and latent factor models to extract deep abstractions and non-linear feature representations of the data for rating prediction. The core idea is to map the dense user and item vectors generated by embedding techniques into dual, fully connected deep neural network architectures. In these two separate architectures, it learns the non-linear representation of the input data. The method then predicts the rating score by integrating the factors obtained from the two independent structures using the inner product. From the experimental result, we observe that the proposed model outperformed state-of-the-art existing models in real-world datasets (MovieLens ML-100K and ML-1M).
Depth estimation of supervised monocular images based on semantic segmentation

In recent years, the research method of depth estimation of target images using Convolutional Neural Networks (CNN) has been widely recognized in the fields of artificial intelligence, scene understanding and three-dimensional (3D) reconstruction. The fusion of semantic segmentation information and depth estimation will further improve the quality of acquired depth images. However, how to deeply combine image semantic information with image depth information and use image edge information more accurately to improve the accuracy of depth image is still an urgent problem to be solved. For this purpose, we propose a novel depth estimation model based on semantic segmentation to estimate the depth of monocular images in this paper. Firstly, a shared parameter model of semantic segmentation information and depth estimation information is built, and the semantic segmentation information is used to guide depth acquisition in an auxiliary way. Then, through the multi-scale feature fusion module, the feature information contained in the neural network on different layers is fused, and the local feature information and global feature information are effectively used to generate high-resolution feature maps, so as to achieve the goal of improving the quality of depth image by optimizing the semantic segmentation model. The experimental results show that the model can fully extract and combine the image feature information, which improves the quality of monocular depth vision estimation. Compared with other advanced models, our model has certain advantages.
LiDAR-Based Local Path Planning Method for Reactive Navigation in Underground Mines

Reactive navigation is the most researched navigation technique for underground vehicles. Local path planning is one of the main research difficulties in reactive navigation. At present, no technique can perfectly solve the problem of local path planning for the reactive navigation of underground vehicles. Aiming to address this problem, this paper proposes a new method for local path planning based on 2D LiDAR. First, we convert the LiDAR data into a binary image, and we then extract the skeleton of the binary image through a thinning algorithm. Finally, we extract the centerline of the current laneway from these skeletons and smooth the obtained roadway centerline as the current planned local path. Experiments show that the proposed method has high robustness and good performance. Additionally, the method can also be used for the global path planning of underground maps.
A Non-Contact Fall Detection Method for Bathroom Application Based on MEMS Infrared Sensors

The ratio of the elderly to the total population around the world is larger than 10%, and about 30% of the elderly are injured by falls each year. Accidental falls, especially bathroom falls, account for a large proportion. Therefore, fall events detection of the elderly is of great importance. In this article, a non-contact fall detector based on a Micro-electromechanical Systems Pyroelectric Infrared (MEMS PIR) sensor and a thermopile IR array sensor is designed to detect bathroom falls. Besides, image processing algorithms with a low pass filter and double boundary scans are put forward in detail. Then, the statistical features of the area, center, duration and temperature are extracted. Finally, a 3-layer BP neural network is adopted to identify the fall events. Taking into account the key factors of ambient temperature, objective, illumination, fall speed, fall state, fall area and fall scene, 640 tests were performed in total, and 5-fold cross validation is adopted. Experimental results demonstrate that the averages of the precision, recall, detection accuracy and F1-Score are measured to be 94.45%, 90.94%, 92.81% and 92.66%, respectively, which indicates that the novel detection method is feasible. Thereby, this IOT detector can be extensively used for household bathroom fall detection and is low-cost and privacy-security guaranteed.
A Novel Regional-Scale Assessment of Soil Metal Pollution in Arid Agroecosystems

This work is a novel trial to integrate geostatistics with fuzzy logic under the geographic information system (GIS) environment to model soil pollution. Soil samples from seventy-one soil profiles in the northern Nile Delta, Egypt, and were analyzed for total concentrations of Cd, Co, Cu, Pb, Ni, and Zn. Metal distribution maps were generated using ordinary kriging methods. They were normalized by linear and non-linear fuzzy membership functions (FMFs) and overlain by fuzzy operators (And, OR, Sum, Product, and Gamma). The final maps were validated using the area under the curve (AUC) of the receiver operating characteristic (ROC). The best-fitted semivariogram models were Gaussian for Cd, Pb, and Ni, circular for Co and Zn, and exponential for Cu. The ROC and AUC analysis revealed that the non-linear FMFs were more effective than the linear functions for modeling soil pollution. Overall, the highest AUC value (0.866; very good accuracy) resulted from applying the fuzzy Sum overly to the non-linearly normalized layers, implying the superiority of this model for decision-making in the studied area. Accordingly, 92% of the investigated soils were severely polluted. Our study would increase insight into soil metal pollution on a regional scale, especially in arid regions.
Hate speech in the Internet context: Unpacking the roles of Internet penetration, online legal regulation, and online opinion polarization from a transnational perspective

Hate speech has plagued human societies for decades and severely influenced the whole world. By analyzing a balanced panel dataset covering 167 countries and 19 years derived from the V-Dem project, the relationships between critical Internet context indicators and online hate speech were disentangled, casting light on how to tackle the hate speech problem on a global scale. We found that Internet penetration was positively associated with online hate speech in general, confirming Internet's technological affordances have the potential to facilitate hate speech expression. Online legal regulation was negatively related to online hate speech but had no significant moderating effect between Internet penetration and online hate speech, reflecting an underlying tension among legal approaches’ comprehensive effects. Online opinion polarization was positively related to online hate speech and significantly moderated the relationship between Internet penetration and online hate speech, which indicated that a polarized opinion atmosphere might exacerbate hate speech and intensify intergroup conflicts. Our findings’ theoretical contributions and policy implications are further discussed.
Improved Deep Deterministic Policy Gradient for Dynamic Obstacle Avoidance of Mobile Robot

When a mobile robot is required to perform tasks in the unknown and complex environment, it is critical to have the ability of dynamic obstacle avoidance. However, conventional deep deterministic policy gradient (DDPG) for collision-free navigation can only perceive a fixed number of dynamic obstacles, and thus it cannot adapt to the stochastic working scenario. To overcome the limitation, an improved DDPG algorithm is proposed in this study. It is an exploration to implement the DDPG with long short-term memory (LSTM) network-based encoder to achieve dynamic obstacle avoidance for the mobile robot in the stochastic working scenario, which can encode the variable number of obstacles into a fixed-length representation. Specifically, to facilitate the LSTM network-based encoder, one safe processing rule is designed to guarantee the entire information of the observable obstacles can be represented completely. The LSTM network-based encoder takes the latest environment information of observable obstacles by employing the safe processing rule and generates the fixed length state vector. In addition, continuous state space for mobile robot and obstacles, as well as reward function and action space are designed. Both simulations and experiments are conducted and the results verify that the improved DDPG algorithm can achieve collision-free trajectory with multiple dynamic obstacles well. It helps to reduce the path distance and motion time effectively.
Perception-Oriented U-Shaped Transformer Network for 360-Degree No-Reference Image Quality Assessment

Generally, 360-degree images have absolute senses of reality and three-dimensionality, providing a wide range of immersive interactions. Due to the novel rendering and display technology of 360-degree images, they have more complex perceptual characteristics than other images. It is challenging to perform comprehensive image quality assessment (IQA) learning by simply stacking multichannel neural network architectures for pre/postprocessing, compression, and rendering tasks. To thoroughly learn the global and local features in 360-degree images, reduce the complexity of multichannel neural network models and simplify the training process, this paper proposes a joint architecture with user perception and an efficient transformer dedicated to 360-degree no-reference (NR) IQA. The input of the proposed method is a 360-degree cube map projection (CMP) image. Furthermore, the proposed 360-degree NRIQA method includes a saliency map-based non-overlapping self-attention selection module and a U-shaped transformer (U-former)-based feature extraction module to account for perceptual region importance and projection distortion. The transformer-based architecture and the weighted average technique are jointly utilized for predicting local perceptual quality. Experimental results obtained on widely used databases show that the proposed model outperforms other state-of-the-art methods in NR 360-degree image quality evaluation cases. Furthermore, a cross-database evaluation and an ablation study also demonstrate the inherent robustness and generalization ability of the proposed model.
Proactive Random-Forest Autoscaler for Microservice Resource Allocation

Cloud service providers have been shifting their workloads to microservices to take advantage of their modularity, flexibility, agility, and scalability. However, numerous obstacles remain to achieving the most out of microservice deployments, especially in terms of a Quality of Service (QoS). One possible approach to overcoming these obstacles is to perform autoscaling, which is the ability of cloud infrastructure and services to scale themselves up or down by changing their resource pool. There are two major categories of autoscaling: reactive and proactive. In reactive autoscaling, a feedback loop based on current workload resource usage is implemented to guide resource scaling. One disadvantage of reactive autoscaling is that it may result in inconsistencies between workload demand and resource allocation. In proactive autoscaling, a prediction model is used to guide the future allocation of resources according to current workload metrics. In this paper, a novel proactive autoscaling method is introduced where a two-state, machine-learning Random Forest (RF) model is designed to forecast the future CPU and memory utilization values required by the microservice workload. These predicted values are then used to adjust the resource pool both vertically (hardware resources) and horizontally (microservice replicas). The RF proactive autoscaler has been implemented on a home-grown, open-source microservice prototyping platform and verified using real-world workloads. The experiments show that the RF proactive autoscaler outperforms state-of-the-art ones in terms of allocated resources and latency. The increase in the utilization of allocated resources can reach 90% and the improvement in end-to-end latency, measured by the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$95^{th}$ </tex-math></inline-formula> percentile, can reach 95%.
Riemannian representation learning for multi-source domain adaptation

Multi-Source Domain Adaptation (MSDA) aims at training a classification model that achieves small target error, by leveraging labeled data from multiple source domains and unlabeled data from a target domain. The source and target domains are described by related but different joint distributions, which lie on a Riemannian manifold named the statistical manifold. In this paper, we characterize the joint distribution difference by the Hellinger distance, which bears strong connection to the Riemannian metric defined on the statistical manifold. We show that the target error of a neural network classification model is upper bounded by the average source error of the model and the average Hellinger distance, i.e., the average of multiple Hellinger distances between the source and target joint distributions in the network representation space. Motivated by the error bound, we introduce Riemannian Representation Learning (RRL): An approach that trains the network model by minimizing (i) the average empirical Hellinger distance with respect to the representation function, and (ii) the average empirical source error with respect to the network model. Specifically, we derive the average empirical Hellinger distance by constructing and solving unconstrained convex optimization problems whose global optimal solutions are easy to find. With the network model trained, we expect it to achieve small error in the target domain. Our experimental results on several image datasets demonstrate that the proposed RRL approach is statistically better than the comparison methods.
Lightweight Semi-supervised Network for Single Image Rain Removal

Deep learning technologies have shown their advantages in Single Image Rain Removal (SIRR) tasks. However, the derained results of most methods are limited to some challenges. First, due to the lack of real-world rainy/clean image pairs, many methods seriously rely on the labeled synthetic training images and will not effectively remove complex rain streaks in real-world scenarios. Second, most existing SIRR models require high computing power, which considerably limits their real-world applications. To address these issues, we propose a Lightweight Semi-supervised Network (LSNet) for SIRR. Our LSNet utilizes a compact semi-supervised framework to improve generalization ability in real-world rainy images removal. Meanwhile, in our semi-supervised framework, we also design a cascaded sub-network, which progressively removes complex rain streaks via a multi-stage manner. Specially, the multi-stage manner is based on a series of cascaded blocks, where we conduct recursive learning strategy to reduce model parameters. Extensive experimental results demonstrate that our method achieves comparable performance to the state-of-the-arts while has fewer parameters.
Negation-based transfer learning for improving biomedical Named Entity Recognition and Relation Extraction

Named Entity Recognition (NER) and Relation Extraction (RE) are two of the most studied tasks in biomedical Natural Language Processing (NLP). The detection of specific terms and entities and the relationships between them are key aspects for the development of more complex automatic systems in the biomedical field. In this work, we explore transfer learning techniques for incorporating information about negation into systems performing NER and RE. The main purpose of this research is to analyse to what extent the successful detection of negated entities in separate tasks helps in the detection of biomedical entities and their relationships.Three neural architectures are proposed in this work, all of them mainly based on Bidirectional Long Short-Term Memory (Bi-LSTM) networks and Conditional Random Fields (CRFs). While the first architecture is devoted to detecting triggers and scopes of negated entities in any domain, two specific models are developed for performing isolated NER tasks and joint NER and RE tasks in the biomedical domain. Then, weights related to negation detection learned by the first architecture are incorporated into those last models. Two different languages, Spanish and English, are taken into account in the experiments.Performance of the biomedical models is analysed both when the weights of the neural networks are randomly initialized, and when weights from the negation detection model are incorporated into them. Improvements of around 3.5% of F-Measure in the English language and more than 7% in the Spanish language are achieved in the NER task, while the NER+RE task increases F-Measure scores by more than 13% for the NER submodel and around 2% for the RE submodel.The obtained results allow us to conclude that negation-based transfer learning techniques are appropriate for performing biomedical NER and RE tasks. These results highlight the importance of detecting negation for improving the identification of biomedical entities and their relationships. The explored techniques show robustness by maintaining consistent results and improvements across different tasks and languages.