Reviewerly/exHarmony huggingface dataset:
A Machine Learning Approach for the Detection and Characterization of Illicit Drug Dealers on Instagram: Model Evaluation Study

Social media use is now ubiquitous, but the growth in social media communications has also made it a convenient digital platform for drug dealers selling controlled substances, opioids, and other illicit drugs. Previous studies and news investigations have reported the use of popular social media platforms as conduits for opioid sales. This study uses deep learning to detect illicit drug dealing on the image and video sharing platform Instagram.The aim of this study was to develop and evaluate a machine learning approach to detect Instagram posts related to illegal internet drug dealing.In this paper, we describe an approach to detect drug dealers by using a deep learning model on Instagram. We collected Instagram posts using a Web scraper between July 2018 and October 2018 and then compared our deep learning model against 3 different machine learning models (eg, random forest, decision tree, and support vector machine) to assess the performance and accuracy of the model. For our deep learning model, we used the long short-term memory unit in the recurrent neural network to learn the pattern of the text of drug dealing posts. We also manually annotated all posts collected to evaluate our model performance and to characterize drug selling conversations.From the 12,857 posts we collected, we detected 1228 drug dealer posts comprising 267 unique users. We used cross-validation to evaluate the 4 models, with our deep learning model reaching 95% on F1 score and performing better than the other 3 models. We also found that by removing the hashtags in the text, the model had better performance. Detected posts contained hashtags related to several drugs, including the controlled substance Xanax (1078/1228, 87.78%), oxycodone/OxyContin (321/1228, 26.14%), and illicit drugs lysergic acid diethylamide (213/1228, 17.34%) and 3,4-methylenedioxy-methamphetamine (94/1228, 7.65%). We also observed the use of communication applications for suspected drug trading through user comments.Our approach using a combination of Web scraping and deep learning was able to detect illegal online drug sellers on Instagram, with high accuracy. Despite increased scrutiny by regulators and policymakers, the Instagram platform continues to host posts from drug dealers, in violation of federal law. Further action needs to be taken to ensure the safety of social media communities and help put an end to this illicit digital channel of sourcing.
Tracking Objects From Satellite Videos: A Velocity Feature Based Correlation Filter

Satellite video target tracking is a new topic in the remote sensing field, which refers to tracking moving objects of interest from satellite video in real time. The target of interest usually occupies only a few pixels in a satellite video image, even when the train is long. Thus, satellite video target tracking still faces new challenges compared with traditional visual tracking, including the detection of low-resolution targets, features with less representation, and targets with an extremely similar background. Little research has been done on satellite video target tracking, and little is known about whether or not the existing tracking algorithms can still work on the satellite video data. This paper, for the first time, intensively investigated 13 typical trackers in traditional visual tracking. The experimental results suggest that most of the state-of-the-art tracking algorithms mainly rely on luminance, color features, or convolutional features, and they fail to track satellite video targets due to their inadequate representation features. To overcome this difficulty, we propose a velocity correlation filter (VCF) algorithm, which employs both a velocity feature and an inertia mechanism (IM) to construct a specific kernel correlation filter for the satellite video target tracking. The velocity feature has a high discriminative ability to detect moving targets in satellite videos, and the IM can prevent model drift adaptively. Experimental results on three real satellite video data sets show that the VCF outperforms state-of-the-art tracking methods with regard to precision and success plots while running at over 100 frames per second.
MOBIUS

Baidu runs the largest commercial web search engine in China, serving hundreds of millions of online users every day in response to a great variety of queries. In order to build a high-efficiency sponsored search engine, we used to adopt a three-layer funnel-shaped structure to screen and sort hundreds of ads from billions of ad candidates subject to the requirement of low response latency and the restraints of computing resources. Given a user query, the top matching layer is responsible for providing semantically relevant ad candidates to the next layer, while the ranking layer at the bottom concerns more about business indicators (e.g., CPM, ROI, etc.) of those ads. The clear separation between the matching and ranking objectives results in a lower commercial return. The Mobius project has been established to address this serious issue. It is our first attempt to train the matching layer to consider CPM as an additional optimization objective besides the query-ad relevance, via directly predicting CTR (click-through rate) from billions of query-ad pairs. Specifically, this paper will elaborate on how we adopt active learning to overcome the insufficiency of click history at the matching layer when training our neural click networks offline, and how we use the SOTA ANN search technique for retrieving ads more efficiently (Here "ANN'' stands for approximate nearest neighbor search). We contribute the solutions to Mobius-V1 as the first version of our next generation query-ad matching system.
Review of research on mobile‐assisted language learning in familiar, authentic environments

Abstract Familiarity with learning contexts is important in the field of mobile‐assisted language learning (MALL). Several review studies on MALL have been published to date. However, scholars have not covered certain aspects of familiar contexts in their reviews, such as which learning/instructional methodologies support learning in familiar contexts or what the affordances of familiar contexts are for language learning. To address this gap, the authors in this study reviewed research articles related to MALL in familiar, authentic environments published in the past 10 years. The reviewed articles were from journals published in the Social Science Citation Index between 2009 and 2018. The main aim of this study was to review the published articles to understand (1) pedagogical approaches, (2) data collection, (3) locations, (4) affordances of authentic environments and (5) issues in MALL research. The results revealed that the most frequent items in reviewed articles were task‐based learning and communicative language teaching (pedagogical approaches); questionnaires, pretest and posttests and interviews (data collection); the local community and campus (locations); daily encounters , language learning and cognitive load (affordances of authentic environments); and small sample sizes and short‐term interventions (issues in MALL research). Based on the results, the authors in this study made several suggestions and provided implications for educators and researchers in the field about MALL in familiar, authentic environments.
Optimal Filtered and Smoothed Estimators for Discrete-Time Linear Systems With Multiple Packet Dropouts Under Markovian Communication Constraints

This paper concentrates on the linear least mean square (LLMS) filtered and smoothed estimators for networked linear stochastic systems. Multiple packet losses, Markovian communication constraints, and superposed process noise are considered simultaneously. In order to reduce the channel load during communication, at every step, just one transmission node is permitted to send data packets. Hence, a Markovian communication protocol is utilized to arrange the packets of these transmission nodes. Moreover, multiple data packet dropouts occur during transmission due to an imperfect communication channel. Therefore, the global observation information cannot be obtained by the state estimator. The real state of Markov chain is assumed to be unknown to the estimator except the transition probability matrix. By means of the innovation analysis approach and orthogonal projection principle, we design Kalman-like estimators in a recursive form. Finally, through simulation experiments, we verify the effectiveness and superiority of the designed algorithm.
The rise of crypto-ransomware in a changing cybercrime landscape: Taxonomising countermeasures

Year in and year out the increasing adaptivity of offenders has maintained ransomware's position as a major cybersecurity threat. The cybersecurity industry has responded with a similar degree of adaptiveness, but has focussed more upon technical (science) than ‘non-technical’ (social science) factors. This article explores empirically how organisations and investigators have reacted to the shift in the ransomware landscape from scareware and locker attacks to the almost exclusive use of crypto-ransomware. We outline how, for various reasons, victims and investigators struggle to respond effectively to this form of threat. By drawing upon in-depth interviews with victims and law enforcement officers involved in twenty-six crypto-ransomware attacks between 2014 and 2018 and using an inductive content analysis method, we develop a data-driven taxonomy of crypto-ransomware countermeasures. The findings of the research indicate that responses to crypto-ransomware are made more complex by the nuanced relationship between the technical (malware which encrypts) and the human (social engineering which still instigates most infections) aspects of an attack. As a consequence, there is no simple technological ‘silver bullet’ that will wipe out the crypto-ransomware threat. Rather, a multi-layered approach is needed which consists of socio-technical measures, zealous front-line managers and active support from senior management.
General Bayesian updating and the loss-likelihood bootstrap

In this paper we revisit the weighted likelihood bootstrap, a method that generates samples from an approximate Bayesian posterior of a parametric model. We show that the same method can be derived, without approximation, under a Bayesian nonparametric model with the parameter of interest defined through minimizing an expected negative loglikelihood under an unknown sampling distribution. This interpretation enables us to extend the weighted likelihood bootstrap to posterior sampling for parameters minimizing an expected loss. We call this method the loss-likelihood bootstrap, and we make a connection between it and general Bayesian updating, which is a way of updating prior belief distributions that does not need the construction of a global probability model, yet requires the calibration of two forms of loss function. The loss-likelihood bootstrap is used to calibrate the general Bayesian posterior by matching asymptotic Fisher information. We demonstrate the proposed method on a number of examples.
Adversarial Inference for Multi-Sentence Video Description

While significant progress has been made in the image captioning task, video description is still in its infancy due to the complex nature of video data. Generating multi-sentence descriptions for long videos is even more challenging. Among the main issues are the fluency and coherence of the generated descriptions, and their relevance to the video. Recently, reinforcement and adversarial learning based methods have been explored to improve the image captioning models; however, both types of methods suffer from a number of issues, e.g. poor readability and high redundancy for RL and stability issues for GANs. In this work, we instead propose to apply adversarial techniques during inference, designing a discriminator which encourages better multi-sentence video description. In addition, we find that a multi-discriminator "hybrid" design, where each discriminator targets one aspect of a description, leads to the best results. Specifically, we decouple the discriminator to evaluate on three criteria: 1) visual relevance to the video, 2) language diversity and fluency, and 3) coherence across sentences. Our approach results in more accurate, diverse, and coherent multi-sentence video descriptions, as shown by automatic as well as human evaluation on the popular ActivityNet Captions dataset.
Joint Active Learning with Feature Selection via CUR Matrix Decomposition

This paper presents an unsupervised learning approach for simultaneous sample and feature selection, which is in contrast to existing works which mainly tackle these two problems separately. In fact the two tasks are often interleaved with each other: noisy and high-dimensional features will bring adverse effect on sample selection, while informative or representative samples will be beneficial to feature selection. Specifically, we propose a framework to jointly conduct active learning and feature selection based on the CUR matrix decomposition. From the data reconstruction perspective, both the selected samples and features can best approximate the original dataset respectively, such that the selected samples characterized by the features are highly representative. In particular, our method runs in one-shot without the procedure of iterative sample selection for progressive labeling. Thus, our model is especially suitable when there are few labeled samples or even in the absence of supervision, which is a particular challenge for existing methods. As the joint learning problem is NP-hard, the proposed formulation involves a convex but non-smooth optimization problem. We solve it efficiently by an iterative algorithm, and prove its global convergence. Experimental results on publicly available datasets corroborate the efficacy of our method compared with the state-of-the-art.
Simultaneous Fidelity and Regularization Learning for Image Restoration

Most existing non-blind restoration methods are based on the assumption that a precise degradation model is known. As the degradation process can only be partially known or inaccurately modeled, images may not be well restored. Rain streak removal and image deconvolution with inaccurate blur kernels are two representative examples of such tasks. For rain streak removal, although an input image can be decomposed into a scene layer and a rain streak layer, there exists no explicit formulation for modeling rain streaks and the composition with scene layer. For blind deconvolution, as estimation error of blur kernel is usually introduced, the subsequent non-blind deconvolution process does not restore the latent image well. In this paper, we propose a principled algorithm within the maximum a posterior framework to tackle image restoration with a partially known or inaccurate degradation model. Specifically, the residual caused by a partially known or inaccurate degradation model is spatially dependent and complexly distributed. With a training set of degraded and ground-truth image pairs, we parameterize and learn the fidelity term for a degradation model in a task-driven manner. Furthermore, the regularization term can also be learned along with the fidelity term, thereby forming a simultaneous fidelity and regularization learning model. Extensive experimental results demonstrate the effectiveness of the proposed model for image deconvolution with inaccurate blur kernels, deconvolution with multiple degradations and rain streak removal.
Estimation of hourly global solar radiation using Multivariate Adaptive Regression Spline (MARS) – A case study of Hong Kong

Solar energy is the most popular resource for power generation among the various available renewable energy alternatives. Solar radiation data are important for solar systems and energy-efficient building designs. Due to the unavailability of measurement, solar radiation prediction models are required. Recently, machine learning techniques were successfully used for predicting solar radiation. However, previous works were mainly focusing on monthly average daily or daily solar radiation. In this study, models for predicting hourly global solar radiation on a horizontal surface were developed based on Multivariate Adaptive Regression Spline (MARS) method. Hourly meteorological data measured in 7 years were used for the study. Sensitivity analysis was conducted using MARS algorithm and the most important variables were selected as inputs of the proposed models. 16 MARS models with different combinations of input variables were proposed. Logistic regression and Artificial Neural Networks (ANN) methods were also used to develop models for comparative study. Finally, the proposed models were evaluated against measurements and compared with existing models. The results showed that the proposed MARS models have good performance in both prediction accuracy and interpretability. The proposed models could be used to estimate effectively the hourly solar radiation according to different combinations of measured variables.
Review on the Application of Artificial Intelligence in Smart Homes

Smart home and artificial intelligence technologies are developing rapidly, and various smart home products associated with artificial intelligence (AI) improved the quality of living for occupants. Although some studies discussed the application of artificial intelligence in smart homes, few publications fully considered the integration of literature and products. In this paper, we aim to answer the research questions of “what is the trend of smart home technology and products” and “what is the relationship between literature and products in smart homes with AI”. Literature reviews and product reviews are given to define the functions and roles of artificial intelligence in smart homes. We determined the application status of artificial intelligence in smart home products and how it is utilized in our house so that we could understand how artificial intelligence is used to make smart homes. Furthermore, our results revealed that there is a delay between literature and products, and smart home intelligent interactions will become more and more popular.
A cloud-edge based data security architecture for sharing and analysing cyber threat information

Cyber-attacks affect every aspect of our lives. These attacks have serious consequences, not only for cyber-security, but also for safety, as the cyber and physical worlds are increasingly linked. Providing effective cyber-security requires cooperation and collaboration among all the entities involved. Increasing the amount of cyber threat information (CTI) available for analysis allows better prediction, prevention and mitigation of cyber-attacks. However, organizations are deterred from sharing their CTI over concerns that sensitive and confidential information may be revealed to others. We address this concern by providing a flexible framework that allows the confidential sharing of CTI for analysis between collaborators. We propose a five-level trust model for a cloud-edge based data sharing infrastructure. The data owner can choose an appropriate trust level and CTI data sanitization approach, ranging from plain text, through anonymization/pseudonymization to homomorphic encryption, in order to manipulate the CTI data prior to sharing it for analysis. Furthermore, this sanitization can be performed by either an edge device or by the cloud service provider, depending upon the level of trust the organization has in the latter. We describe our trust model, our cloud-edge infrastructure, and its deployment model, which are designed to satisfy the broadest range of requirements for confidential CTI data sharing. Finally we briefly describe our implementation and the testing that has been carried out so far by four pilot projects that are validating our infrastructure.
Class-specific attribute value weighting for Naive Bayes

Naive Bayes (NB) is one of the top 10 data mining algorithms. However, its assumption of conditional independence rarely holds true in real-world applications. To alleviate this assumption, numerous attribute weighting approaches have been proposed. However, few of these simultaneously pay attention to the horizontal granularity of attribute values and vertical granularity of class labels. In this study, we propose a new paradigm for fine-grained attribute weighting, named class-specific attribute value weighting. For each class, this approach discriminatively assigns a specific weight to each attribute value. We refer to the resulting improved model as class-specific attribute value weighted NB (CAVWNB). In CAVWNB, the class-specific attribute value weight matrix is learned by either maximizing the conditional log-likelihood (CLL) or minimizing the mean squared error (MSE). Thus, two versions are proposed, which we denote as CAVWNBCLL and CAVWNBMSE, respectively. Extensive experimental results on a large number of datasets show that both CAVWNBCLL and CAVWNBMSE significantly outperform NB and all the other existing state-of-the-art attribute weighting approaches used for comparison.
Bitcoin mining: A global review of energy and power demand

After its introduction in 2008, increasing Bitcoin prices and a booming number of other cryptocurrencies lead to a growing discussion of how much energy is consumed during the production of these currencies. Being the most expensive and the most popular cryptocurrency, both the business world and the research community have started to question the energy intensity of Bitcoin mining. This paper only focuses on computational power demand during the proof-of-work process rather than estimating the whole energy intensity of mining. We make use of 160GB of Bitcoin blockchain data to estimate the energy consumption and power demand of Bitcoin mining. We considered the performance of 269 different hardware models (CPU, GPU, FPGA, and ASIC). For estimations, we defined two metrics, namely; minimum consumption and maximum consumption. The targeted time span for the analysis was from 3 January 2009 to 5 June 2018. We show that the historical peak of power consumption of Bitcoin mining took place during the bi-weekly period commencing on 18 December 2017 with a demand of between 1.3 and 14.8 GW. This maximum demand figure was between the installed capacities of Finland (∼16 GW) and Denmark (∼14 GW). We also show that, during June 2018, energy consumption of Bitcoin mining from difficulty recalculation was between 15.47 and 50.24 TWh per year.