Reviewerly/exHarmony huggingface dataset:
Towards Automating Healthcare Question Answering in a Noisy Multilingual Low-Resource Setting

We discuss ongoing work into automating a multilingual digital helpdesk service available via text messaging to pregnant and breastfeeding mothers in South Africa. Our anonymized dataset consists of short informal questions, often in low-resource languages, with unreliable language labels, spelling errors and code-mixing, as well as template answers with some inconsistencies. We explore cross-lingual word embeddings, and train parametric and non-parametric models on 90K samples for answer selection from a set of 126 templates. Preliminary results indicate that LSTMs trained end-to-end perform best, with a test accuracy of 62.13% and a recall@5 of 89.56%, and demonstrate that we can accelerate response time by several orders of magnitude.
3-D face registration solution with speckle encoding based spatial-temporal logical correlation algorithm

3-D information acquisition (registration) of whole face plays a significant role in 3-D human face recognition application. In this paper, we develop a prototype of 3-D system consisting of two binocular measurement units that allows a full 3-D reconstruction by utilizing the advantages of a novel correlation algorithm. In this system, we use optical modulation to produce temporally and spatially varying high-density binary speckle patterns to encode the tested face, then propose a spatial-temporal logical correlation (STLC) stereo matching algorithm to fast determine the accurate disparity with a coarse and refined strategy. Finally the 3-D information of whole face from left- and right ear (~180°) can be obtainable by fusing the data from two measurement units. Comparative researches are performed to test a plastic model and a real human face by simulating real application situations. The results verify the feasibility and good performances of our computational frameworks and experimental configuration in terms of accuracy and time cost, which show a good application prospect in our future 3-D human face recognition research.
On Theory for BART

Ensemble learning is a statistical paradigm built on the premise that many weak learners can perform exceptionally well when deployed collectively. The BART method of Chipman et al. (2010) is a prominent example of Bayesian ensemble learning, where each learner is a tree. Due to its impressive performance, BART has received a lot of attention from practitioners. Despite its wide popularity, however, theoretical studies of BART have begun emerging only very recently. Laying down foundation for the theoretical analysis of Bayesian forests, Rockova and van der Pas (2017) showed optimal posterior concentration under conditionally uniform tree priors. These priors deviate from the actual priors implemented in BART. Here, we study the exact BART prior and propose a simple modification so that it also enjoys optimality properties. To this end, we dive into the branching processes theory. We obtain tail bounds for the distribution of total progeny under heterogeneous Galton-Watson (GW) processes using their connection to random walks. We conclude with a result stating optimal rate of convergence for BART.
Personalized Exposure Control Using Adaptive Metering and Reinforcement Learning

We propose a reinforcement learning approach for real-time exposure control of a mobile camera that is personalizable. Our approach is based on Markov Decision Process (MDP). In the camera viewfinder or live preview mode, given the current frame, our system predicts the change in exposure so as to optimize the trade-off among image quality, fast convergence, and minimal temporal oscillation. We model the exposure prediction function as a fully convolutional neural network that can be trained through Gaussian policy gradient in an end-to-end fashion. As a result, our system can associate scene semantics with exposure values; it can also be extended to personalize the exposure adjustments for a user and device. We improve the learning performance by incorporating an adaptive metering module that links semantics with exposure. This adaptive metering module generalizes the conventional spot or matrix metering techniques. We validate our system using the MIT FiveK [1] and our own datasets captured using iPhone 7 and Google Pixel. Experimental results show that our system exhibits stable real-time behavior while improving visual quality compared to what is achieved through native camera control.
SAGE: A Hybrid Geopolitical Event Forecasting System

Forecasting of geopolitical events is a notoriously difficult task, with experts failing to significantly outperform a random baseline across many types of forecasting events. One successful way to increase the performance of forecasting tasks is to turn to crowdsourcing: leveraging many forecasts from non-expert users. Simultaneously, advances in machine learning have led to models that can produce reasonable, although not perfect, forecasts for many tasks. Recent efforts have shown that forecasts can be further improved by ``hybridizing'' human forecasters: pairing them with the machine models in an effort to combine the unique advantages of both. In this demonstration, we present Synergistic Anticipation of Geopolitical Events (SAGE), a platform for human/computer interaction that facilitates human reasoning with machine models.
VIREL: A Variational Inference Framework for Reinforcement Learning

Applying probabilistic models to reinforcement learning (RL) enables the uses of powerful optimisation tools such as variational inference in RL. However, existing inference frameworks and their algorithms pose significant challenges for learning optimal policies, e.g., the lack of mode capturing behaviour in pseudo-likelihood methods, difficulties learning deterministic policies in maximum entropy RL based approaches, and a lack of analysis when function approximators are used. We propose VIREL, a theoretically grounded probabilistic inference framework for RL that utilises a parametrised action-value function to summarise future dynamics of the underlying MDP, generalising existing approaches. VIREL also benefits from a mode-seeking form of KL divergence, the ability to learn deterministic optimal polices naturally from inference, and the ability to optimise value functions and policies in separate, iterative steps. In applying variational expectation-maximisation to VIREL, we thus show that the actor-critic algorithm can be reduced to expectation-maximisation, with policy improvement equivalent to an E-step and policy evaluation to an M-step. We then derive a family of actor-critic methods fromVIREL, including a scheme for adaptive exploration. Finally, we demonstrate that actor-critic algorithms from this family outperform state-of-the-art methods based on soft value functions in several domains.
Cryptanalysis of a Novel Bit-Level Color Image Encryption Using Improved 1D Chaotic Map

Recently, a novel bit-level color image encryption scheme based on improved one-dimension (1D) chaotic map has been proposed. It was claimed that the proposed scheme is secure due to the improved 1D chaotic map with better chaotic performance. Some security analyses and simulation experiments were presented to show that it could resist various attacks. However, we found that there are some security loopholes in the original scheme, and then proposed an effective attack strategy utilizing chosen-plaintext attack (CPA) in this paper. The proposed strategy mainly includes two attacks. The first is to obtain the equivalent secret key of the diffusion right shift phase, and the second is to obtain the permutation right shift rule. The effectiveness and feasibility of the proposed method are verified by both theoretical analyses and experimental results. Some proposals are also given for improving the security of the original encryption scheme.
Scalable Inference for Sparse Deep Neural Networks using Kokkos Kernels

Over the last decade, hardware advances have led to the feasibility of training and inference for very large deep neural networks. Sparsified deep neural networks (DNNs) can greatly reduce memory costs and increase throughput of standard DNNs, if loss of accuracy can be controlled. The IEEE HPEC Sparse Deep Neural Network Graph Challenge serves as a testbed for algorithmic and implementation advances to maximize computational performance of sparse deep neural networks. We base our sparse network for DNNs, KK-SpDNN, on the sparse linear algebra kernels within the Kokkos Kernels library. Using the sparse matrix-matrix multiplication in Kokkos Kernels allows us to reuse a highly optimized kernel. We focus on reducing the single node and multi-node runtimes for 12 sparse networks. We test KK-SpDNN on Intel Skylake and Knights Landing architectures and see 120-500x improvement on single node performance over the serial reference implementation. We run in data-parallel mode with MPI to further speed up network inference, ultimately obtaining an edge processing rate of 1.16e+12 on 20 Skylake nodes. This translates to a 13x speed up on 20 nodes compared to our highly optimized multithreaded implementation on a single Skylake node.
A New Model of RGB-D Camera Calibration Based On 3D Control Field

With extensive application of RGB-D cameras in robotics, computer vision, and many other fields, accurate calibration becomes more and more critical to the sensors. However, most existing models for calibrating depth and the relative pose between a depth camera and an RGB camera are not universally applicable to many different kinds of RGB-D cameras. In this paper, by using the collinear equation and space resection of photogrammetry, we present a new model to correct the depth and calibrate the relative pose between depth and RGB cameras based on a 3D control field. We establish a rigorous relationship model between the two cameras; then, we optimize the relative parameters of two cameras by least-squares iteration. For depth correction, based on the extrinsic parameters related to object space, the reference depths are calculated by using a collinear equation. Then, we calibrate the depth measurements with consideration of the distortion of pixels in depth images. We apply Kinect-2 to verify the calibration parameters by registering depth and color images. We test the effect of depth correction based on 3D reconstruction. Compared to the registration results from a state-of-the-art calibration model, the registration results obtained with our calibration parameters improve dramatically. Likewise, the performances of 3D reconstruction demonstrate obvious improvements after depth correction.
Many-Objective Test Suite Generation for Software Product Lines

A Software Product Line (SPL) is a set of products built from a number of features, the set of valid products being defined by a feature model. Typically, it does not make sense to test all products defined by an SPL and one instead chooses a set of products to test (test selection) and, ideally, derives a good order in which to test them (test prioritisation). Since one cannot know in advance which products will reveal faults, test selection and prioritisation are normally based on objective functions that are known to relate to likely effectiveness or cost. This article introduces a new technique, the grid-based evolution strategy (GrES), which considers several objective functions that assess a selection or prioritisation and aims to optimise on all of these. The problem is thus a many-objective optimisation problem. We use a new approach, in which all of the objective functions are considered but one (pairwise coverage) is seen as the most important. We also derive a novel evolution strategy based on domain knowledge. The results of the evaluation, on randomly generated and realistic feature models, were promising, with GrES outperforming previously proposed techniques and a range of many-objective optimisation algorithms.
Dynamical Distance Learning for Semi-Supervised and Unsupervised Skill Discovery

Reinforcement learning requires manual specification of a reward function to learn a task. While in principle this reward function only needs to specify the task goal, in practice reinforcement learning can be very time-consuming or even infeasible unless the reward function is shaped so as to provide a smooth gradient towards a successful outcome. This shaping is difficult to specify by hand, particularly when the task is learned from raw observations, such as images. In this paper, we study how we can automatically learn dynamical distances: a measure of the expected number of time steps to reach a given goal state from any other state. These dynamical distances can be used to provide well-shaped reward functions for reaching new goals, making it possible to learn complex tasks efficiently. We show that dynamical distances can be used in a semi-supervised regime, where unsupervised interaction with the environment is used to learn the dynamical distances, while a small amount of preference supervision is used to determine the task goal, without any manually engineered reward function or goal examples. We evaluate our method both on a real-world robot and in simulation. We show that our method can learn to turn a valve with a real-world 9-DoF hand, using raw image observations and just ten preference labels, without any other supervision. Videos of the learned skills can be found on the project website: https://sites.google.com/view/skills-via-distance-learning.
Exploiting trust for financial gain: an overview of business email compromise (BEC) fraud

Purpose This paper aims to explore current knowledge of business email compromise (BEC) fraud, or approaches that specifically target organisations for financial gain, through the exploitation of trusted relationships. BEC fraud affects organisations globally and is estimated to have netted offenders over US$26bn since 2016. Despite the sheer magnitude of these losses, there is a dearth of academic research seeking to better understand this crime type, and prevent it from occurring. Design/methodology/approach This review summarises the known literature on BEC fraud. It uses a variety of academic and industry sources to ascertain the current state of knowledge, including how it is perpetrated, its impact (on businesses and individuals), how law enforcement have responded and its prevention. Findings This review highlights many gaps in knowledge surrounding BEC fraud. There has been a large focus on the technical aspects of BEC fraud, to the detriment of the human elements. Often, BEC fraud is successful through targeted and effective use of social engineering techniques and is able to overcome any technical solutions through the manipulation of personal relationships. Further, while the financial impacts of BEC fraud are obvious, there is no known research which has explored the non-financial harms of BEC fraud (across organisational and individual perspectives). With companies starting to (unsuccessfully) take legal action against those who have responded, there is a clear need to understand how organisations can better respond to incidents when they occur. Finally, there are gaps in knowledge on what is the best combination of both technical and human measures to prevent BEC fraud. Research limitations/implications This review is based on information presently available, and as indicated, there are significant gaps in what is currently known. Practical implications This review highlights the need to undertake research into the current gaps, with a view to improving best practice knowledge on prevention and response. Social implications Currently unknown, BEC fraud is posited to have significant impacts at both personal and collective levels. Increased knowledge of these non-financial impacts will improve how organisations respond to BEC fraud and how employees can be supported before and after an incident occurs. Originality/value Despite the magnitude of the problem, there is limited academic scholarship on BEC fraud. This literature review offers a summary of current knowledge and advocates a strong research agenda moving forward.
Vision-based tracking system for augmented reality to localize recurrent laryngeal nerve during robotic thyroid surgery

Abstract We adopted a vision-based tracking system for augmented reality (AR), and evaluated whether it helped surgeons to localize the recurrent laryngeal nerve (RLN) during robotic thyroid surgery. We constructed an AR image of the trachea, common carotid artery, and RLN using CT images. During surgery, an AR image of the trachea and common carotid artery were overlaid on the physical structures after they were exposed. The vision-based tracking system was activated so that the AR image of the RLN followed the camera movement. After identifying the RLN, the distance between the AR image of the RLN and the actual RLN was measured. Eleven RLNs (9 right, 4 left) were tested. The mean distance between the RLN AR image and the actual RLN was 1.9 ± 1.5 mm (range 0.5 to 3.7). RLN localization using AR and vision-based tracking system was successfully applied during robotic thyroidectomy. There were no cases of RLN palsy. This technique may allow surgeons to identify hidden anatomical structures during robotic surgery.
Deep Isometric Learning for Visual Recognition

Initialization, normalization, and skip connections are believed to be three indispensable techniques for training very deep convolutional neural networks and obtaining state-of-the-art performance. This paper shows that deep vanilla ConvNets without normalization nor skip connections can also be trained to achieve surprisingly good performance on standard image recognition benchmarks. This is achieved by enforcing the convolution kernels to be near isometric during initialization and training, as well as by using a variant of ReLU that is shifted towards being isometric. Further experiments show that if combined with skip connections, such near isometric networks can achieve performances on par with (for ImageNet) and better than (for COCO) the standard ResNet, even without normalization at all. Our code is available at this https URL.
Laplacian Regularized Few-Shot Learning

We propose a transductive Laplacian-regularized inference for few-shot tasks. Given any feature embedding learned from the base classes, we minimize a quadratic binary-assignment function containing two terms: (1) a unary term assigning query samples to the nearest class prototype, and (2) a pairwise Laplacian term encouraging nearby query samples to have consistent label assignments. Our transductive inference does not re-train the base model, and can be viewed as a graph clustering of the query set, subject to supervision constraints from the support set. We derive a computationally efficient bound optimizer of a relaxation of our function, which computes independent (parallel) updates for each query sample, while guaranteeing convergence. Following a simple cross-entropy training on the base classes, and without complex meta-learning strategies, we conducted comprehensive experiments over five few-shot learning benchmarks. Our LaplacianShot consistently outperforms state-of-the-art methods by significant margins across different models, settings, and data sets. Furthermore, our transductive inference is very fast, with computational times that are close to inductive inference, and can be used for large-scale few-shot tasks.
DATE

Intentional manipulation of invoices that lead to undervaluation of trade goods is the most common type of customs fraud to avoid ad valorem duties and taxes. To secure government revenue without interrupting legitimate trade flows, customs administrations around the world strive to develop ways to detect illicit trades. This paper proposes DATE, a model of Dual-task Attentive Tree-aware Embedding, to classify and rank illegal trade flows that contribute the most to the overall customs revenue when caught. The strength of DATE comes from combining a tree-based model for interpretability and transaction-level embeddings with dual attention mechanisms. To accurately identify illicit transactions and predict tax revenue, DATE learns simultaneously from illicitness and surtax of each transaction. With a five-year amount of customs import data with a test illicit ratio of 2.24%, DATE shows a remarkable precision of 92.7% on illegal cases and a recall of 49.3% on revenue after inspecting only 1% of all trade flows. We also discuss issues on deploying DATE in Nigeria Customs Service, in collaboration with the World Customs Organization.
Pine: Enabling Privacy-Preserving Deep Packet Inspection on TLS with Rule-Hiding and Fast Connection Establishment

Transport Layer Security Inspection (TLSI) enables enterprises to decrypt, inspect and then re-encrypt users’ traffic before it is routed to the destination. This breaks the end-to-end security guarantee of the TLS specification and implementation. It also raises privacy concerns since users’ traffic is now known by the enterprises, and third-party middlebox providers providing the inspection services may additionally learn the inspection or attack rules, policies of the enterprises. Two recent works, BlindBox (SIGCOMM 2015) and PrivDPI (CCS 2019) propose privacy-preserving approaches that inspect encrypted traffic directly to address the privacy concern of users’ traffic. However, BlindBox incurs high preprocessing overhead during TLS connection establishment, and while PrivDPI reduces the overhead substantially, it is still notable compared to that of TLSI. Furthermore, the underlying assumption in both approaches is that the middlebox knows the rule sets. Nevertheless, with the services increasingly migrating to third-party cloud-based setting, rule privacy should be preserved. Also, both approaches are static in nature in the sense that addition of any rules requires significant amount of preprocessing and re-instantiation of the protocols. In this paper we propose Pine, a new Privacy-preserving inspection of encrypted traffic protocol that (1) simplifies the preprocessing step of PrivDPI thus further reduces the computation time and communication overhead of establishing the TLS connection between a user and a server; (2) supports rule hiding; and (3) enables dynamic rule addition without the need to re-execute the protocol from scratch. We demonstrate the superior performance of Pine when compared to PrivDPI through extensive experimentations. In particular, for a connection from a client to a server with 5,000 tokens and 6,000 rules, Pine is approximately 27% faster and saves approximately 92.3% communication cost.