k Phase retrieval of complex-valued objects via a randomized Kaczmarz method. (arXiv:2005.03238v1 [cs.IT]) By arxiv.org Published On :: This paper investigates the convergence of the randomized Kaczmarz algorithm for the problem of phase retrieval of complex-valued objects. While this algorithm has been studied for the real-valued case}, its generalization to the complex-valued case is nontrivial and has been left as a conjecture. This paper establishes the connection between the convergence of the algorithm and the convexity of an objective function. Based on the connection, it demonstrates that when the sensing vectors are sampled uniformly from a unit sphere and the number of sensing vectors $m$ satisfies $m>O(nlog n)$ as $n, m ightarrowinfty$, then this algorithm with a good initialization achieves linear convergence to the solution with high probability. Full Article
k Mortar-based entropy-stable discontinuous Galerkin methods on non-conforming quadrilateral and hexahedral meshes. (arXiv:2005.03237v1 [math.NA]) By arxiv.org Published On :: High-order entropy-stable discontinuous Galerkin (DG) methods for nonlinear conservation laws reproduce a discrete entropy inequality by combining entropy conservative finite volume fluxes with summation-by-parts (SBP) discretization matrices. In the DG context, on tensor product (quadrilateral and hexahedral) elements, SBP matrices are typically constructed by collocating at Lobatto quadrature points. Recent work has extended the construction of entropy-stable DG schemes to collocation at more accurate Gauss quadrature points. In this work, we extend entropy-stable Gauss collocation schemes to non-conforming meshes. Entropy-stable DG schemes require computing entropy conservative numerical fluxes between volume and surface quadrature nodes. On conforming tensor product meshes where volume and surface nodes are aligned, flux evaluations are required only between "lines" of nodes. However, on non-conforming meshes, volume and surface nodes are no longer aligned, resulting in a larger number of flux evaluations. We reduce this expense by introducing an entropy-stable mortar-based treatment of non-conforming interfaces via a face-local correction term, and provide necessary conditions for high-order accuracy. Numerical experiments in both two and three dimensions confirm the stability and accuracy of this approach. Full Article
k Constructing Accurate and Efficient Deep Spiking Neural Networks with Double-threshold and Augmented Schemes. (arXiv:2005.03231v1 [cs.NE]) By arxiv.org Published On :: Spiking neural networks (SNNs) are considered as a potential candidate to overcome current challenges such as the high-power consumption encountered by artificial neural networks (ANNs), however there is still a gap between them with respect to the recognition accuracy on practical tasks. A conversion strategy was thus introduced recently to bridge this gap by mapping a trained ANN to an SNN. However, it is still unclear that to what extent this obtained SNN can benefit both the accuracy advantage from ANN and high efficiency from the spike-based paradigm of computation. In this paper, we propose two new conversion methods, namely TerMapping and AugMapping. The TerMapping is a straightforward extension of a typical threshold-balancing method with a double-threshold scheme, while the AugMapping additionally incorporates a new scheme of augmented spike that employs a spike coefficient to carry the number of typical all-or-nothing spikes occurring at a time step. We examine the performance of our methods based on MNIST, Fashion-MNIST and CIFAR10 datasets. The results show that the proposed double-threshold scheme can effectively improve accuracies of the converted SNNs. More importantly, the proposed AugMapping is more advantageous for constructing accurate, fast and efficient deep SNNs as compared to other state-of-the-art approaches. Our study therefore provides new approaches for further integration of advanced techniques in ANNs to improve the performance of SNNs, which could be of great merit to applied developments with spike-based neuromorphic computing. Full Article
k Hierarchical Predictive Coding Models in a Deep-Learning Framework. (arXiv:2005.03230v1 [cs.CV]) By arxiv.org Published On :: Bayesian predictive coding is a putative neuromorphic method for acquiring higher-level neural representations to account for sensory input. Although originating in the neuroscience community, there are also efforts in the machine learning community to study these models. This paper reviews some of the more well known models. Our review analyzes module connectivity and patterns of information transfer, seeking to find general principles used across the models. We also survey some recent attempts to cast these models within a deep learning framework. A defining feature of Bayesian predictive coding is that it uses top-down, reconstructive mechanisms to predict incoming sensory inputs or their lower-level representations. Discrepancies between the predicted and the actual inputs, known as prediction errors, then give rise to future learning that refines and improves the predictive accuracy of learned higher-level representations. Predictive coding models intended to describe computations in the neocortex emerged prior to the development of deep learning and used a communication structure between modules that we name the Rao-Ballard protocol. This protocol was derived from a Bayesian generative model with some rather strong statistical assumptions. The RB protocol provides a rubric to assess the fidelity of deep learning models that claim to implement predictive coding. Full Article
k End-to-End Domain Adaptive Attention Network for Cross-Domain Person Re-Identification. (arXiv:2005.03222v1 [cs.CV]) By arxiv.org Published On :: Person re-identification (re-ID) remains challenging in a real-world scenario, as it requires a trained network to generalise to totally unseen target data in the presence of variations across domains. Recently, generative adversarial models have been widely adopted to enhance the diversity of training data. These approaches, however, often fail to generalise to other domains, as existing generative person re-identification models have a disconnect between the generative component and the discriminative feature learning stage. To address the on-going challenges regarding model generalisation, we propose an end-to-end domain adaptive attention network to jointly translate images between domains and learn discriminative re-id features in a single framework. To address the domain gap challenge, we introduce an attention module for image translation from source to target domains without affecting the identity of a person. More specifically, attention is directed to the background instead of the entire image of the person, ensuring identifying characteristics of the subject are preserved. The proposed joint learning network results in a significant performance improvement over state-of-the-art methods on several benchmark datasets. Full Article
k Multi-dimensional Avikainen's estimates. (arXiv:2005.03219v1 [math.PR]) By arxiv.org Published On :: Avikainen proved the estimate $mathbb{E}[|f(X)-f(widehat{X})|^{q}] leq C(p,q) mathbb{E}[|X-widehat{X}|^{p}]^{frac{1}{p+1}} $ for $p,q in [1,infty)$, one-dimensional random variables $X$ with the bounded density function and $widehat{X}$, and a function $f$ of bounded variation in $mathbb{R}$. In this article, we will provide multi-dimensional analogues of this estimate for functions of bounded variation in $mathbb{R}^{d}$, Orlicz-Sobolev spaces, Sobolev spaces with variable exponents and fractional Sobolev spaces. The main idea of our arguments is to use Hardy-Littlewood maximal estimates and pointwise characterizations of these function spaces. We will apply main statements to numerical analysis on irregular functionals of a solution to stochastic differential equations based on the Euler-Maruyama scheme and the multilevel Monte Carlo method, and to estimates of the $L^{2}$-time regularity of decoupled forward-backward stochastic differential equations with irregular terminal conditions. Full Article
k Hierarchical Attention Network for Action Segmentation. (arXiv:2005.03209v1 [cs.CV]) By arxiv.org Published On :: The temporal segmentation of events is an essential task and a precursor for the automatic recognition of human actions in the video. Several attempts have been made to capture frame-level salient aspects through attention but they lack the capacity to effectively map the temporal relationships in between the frames as they only capture a limited span of temporal dependencies. To this end we propose a complete end-to-end supervised learning approach that can better learn relationships between actions over time, thus improving the overall segmentation performance. The proposed hierarchical recurrent attention framework analyses the input video at multiple temporal scales, to form embeddings at frame level and segment level, and perform fine-grained action segmentation. This generates a simple, lightweight, yet extremely effective architecture for segmenting continuous video streams and has multiple application domains. We evaluate our system on multiple challenging public benchmark datasets, including MERL Shopping, 50 salads, and Georgia Tech Egocentric datasets, and achieves state-of-the-art performance. The evaluated datasets encompass numerous video capture settings which are inclusive of static overhead camera views and dynamic, ego-centric head-mounted camera views, demonstrating the direct applicability of the proposed framework in a variety of settings. Full Article
k A Stochastic Geometry Approach to Doppler Characterization in a LEO Satellite Network. (arXiv:2005.03205v1 [cs.IT]) By arxiv.org Published On :: A Non-terrestrial Network (NTN) comprising Low Earth Orbit (LEO) satellites can enable connectivity to underserved areas, thus complementing existing telecom networks. The high-speed satellite motion poses several challenges at the physical layer such as large Doppler frequency shifts. In this paper, an analytical framework is developed for statistical characterization of Doppler shift in an NTN where LEO satellites provide communication services to terrestrial users. Using tools from stochastic geometry, the users within a cell are grouped into disjoint clusters to limit the differential Doppler across users. Under some simplifying assumptions, the cumulative distribution function (CDF) and the probability density function are derived for the Doppler shift magnitude at a random user within a cluster. The CDFs are also provided for the minimum and the maximum Doppler shift magnitude within a cluster. Leveraging the analytical results, the interplay between key system parameters such as the cluster size and satellite altitude is examined. Numerical results validate the insights obtained from the analysis. Full Article
k What comprises a good talking-head video generation?: A Survey and Benchmark. (arXiv:2005.03201v1 [cs.CV]) By arxiv.org Published On :: Over the years, performance evaluation has become essential in computer vision, enabling tangible progress in many sub-fields. While talking-head video generation has become an emerging research topic, existing evaluations on this topic present many limitations. For example, most approaches use human subjects (e.g., via Amazon MTurk) to evaluate their research claims directly. This subjective evaluation is cumbersome, unreproducible, and may impend the evolution of new research. In this work, we present a carefully-designed benchmark for evaluating talking-head video generation with standardized dataset pre-processing strategies. As for evaluation, we either propose new metrics or select the most appropriate ones to evaluate results in what we consider as desired properties for a good talking-head video, namely, identity preserving, lip synchronization, high video quality, and natural-spontaneous motion. By conducting a thoughtful analysis across several state-of-the-art talking-head generation approaches, we aim to uncover the merits and drawbacks of current methods and point out promising directions for future work. All the evaluation code is available at: https://github.com/lelechen63/talking-head-generation-survey. Full Article
k ContextNet: Improving Convolutional Neural Networks for Automatic Speech Recognition with Global Context. (arXiv:2005.03191v1 [eess.AS]) By arxiv.org Published On :: Convolutional neural networks (CNN) have shown promising results for end-to-end speech recognition, albeit still behind other state-of-the-art methods in performance. In this paper, we study how to bridge this gap and go beyond with a novel CNN-RNN-transducer architecture, which we call ContextNet. ContextNet features a fully convolutional encoder that incorporates global context information into convolution layers by adding squeeze-and-excitation modules. In addition, we propose a simple scaling method that scales the widths of ContextNet that achieves good trade-off between computation and accuracy. We demonstrate that on the widely used LibriSpeech benchmark, ContextNet achieves a word error rate (WER) of 2.1\%/4.6\% without external language model (LM), 1.9\%/4.1\% with LM and 2.9\%/7.0\% with only 10M parameters on the clean/noisy LibriSpeech test sets. This compares to the previous best published system of 2.0\%/4.6\% with LM and 3.9\%/11.3\% with 20M parameters. The superiority of the proposed ContextNet model is also verified on a much larger internal dataset. Full Article
k Evolutionary Multi Objective Optimization Algorithm for Community Detection in Complex Social Networks. (arXiv:2005.03181v1 [cs.NE]) By arxiv.org Published On :: Most optimization-based community detection approaches formulate the problem in a single or bi-objective framework. In this paper, we propose two variants of a three-objective formulation using a customized non-dominated sorting genetic algorithm III (NSGA-III) to find community structures in a network. In the first variant, named NSGA-III-KRM, we considered Kernel k means, Ratio cut, and Modularity, as the three objectives, whereas the second variant, named NSGA-III-CCM, considers Community score, Community fitness and Modularity, as three objective functions. Experiments are conducted on four benchmark network datasets. Comparison with state-of-the-art approaches along with decomposition-based multi-objective evolutionary algorithm variants (MOEA/D-KRM and MOEA/D-CCM) indicates that the proposed variants yield comparable or better results. This is particularly significant because the addition of the third objective does not worsen the results of the other two objectives. We also propose a simple method to rank the Pareto solutions so obtained by proposing a new measure, namely the ratio of the hyper-volume and inverted generational distance (IGD). The higher the ratio, the better is the Pareto set. This strategy is particularly useful in the absence of empirical attainment function in the multi-objective framework, where the number of objectives is more than two. Full Article
k Lattice-based public key encryption with equality test in standard model, revisited. (arXiv:2005.03178v1 [cs.CR]) By arxiv.org Published On :: Public key encryption with equality test (PKEET) allows testing whether two ciphertexts are generated by the same message or not. PKEET is a potential candidate for many practical applications like efficient data management on encrypted databases. Potential applicability of PKEET leads to intensive research from its first instantiation by Yang et al. (CT-RSA 2010). Most of the followup constructions are secure in the random oracle model. Moreover, the security of all the concrete constructions is based on number-theoretic hardness assumptions which are vulnerable in the post-quantum era. Recently, Lee et al. (ePrint 2016) proposed a generic construction of PKEET schemes in the standard model and hence it is possible to yield the first instantiation of PKEET schemes based on lattices. Their method is to use a $2$-level hierarchical identity-based encryption (HIBE) scheme together with a one-time signature scheme. In this paper, we propose, for the first time, a direct construction of a PKEET scheme based on the hardness assumption of lattices in the standard model. More specifically, the security of the proposed scheme is reduces to the hardness of the Learning With Errors problem. Full Article
k A Parameterized Perspective on Attacking and Defending Elections. (arXiv:2005.03176v1 [cs.GT]) By arxiv.org Published On :: We consider the problem of protecting and manipulating elections by recounting and changing ballots, respectively. Our setting involves a plurality-based election held across multiple districts, and the problem formulations are based on the model proposed recently by~[Elkind et al, IJCAI 2019]. It turns out that both of the manipulation and protection problems are NP-complete even in fairly simple settings. We study these problems from a parameterized perspective with the goal of establishing a more detailed complexity landscape. The parameters we consider include the number of voters, and the budgets of the attacker and the defender. While we observe fixed-parameter tractability when parameterizing by number of voters, our main contribution is a demonstration of parameterized hardness when working with the budgets of the attacker and the defender. Full Article
k Nonlinear model reduction: a comparison between POD-Galerkin and POD-DEIM methods. (arXiv:2005.03173v1 [physics.comp-ph]) By arxiv.org Published On :: Several nonlinear model reduction techniques are compared for the three cases of the non-parallel version of the Kuramoto-Sivashinsky equation, the transient regime of flow past a cylinder at $Re=100$ and fully developed flow past a cylinder at the same Reynolds number. The linear terms of the governing equations are reduced by Galerkin projection onto a POD basis of the flow state, while the reduced nonlinear convection terms are obtained either by a Galerkin projection onto the same state basis, by a Galerkin projection onto a POD basis representing the nonlinearities or by applying the Discrete Empirical Interpolation Method (DEIM) to a POD basis of the nonlinearities. The quality of the reduced order models is assessed as to their stability, accuracy and robustness, and appropriate quantitative measures are introduced and compared. In particular, the properties of the reduced linear terms are compared to those of the full-scale terms, and the structure of the nonlinear quadratic terms is analyzed as to the conservation of kinetic energy. It is shown that all three reduction techniques provide excellent and similar results for the cases of the Kuramoto-Sivashinsky equation and the limit-cycle cylinder flow. For the case of the transient regime of flow past a cylinder, only the pure Galerkin techniques are successful, while the DEIM technique produces reduced-order models that diverge in finite time. Full Article
k On Optimal Control of Discounted Cost Infinite-Horizon Markov Decision Processes Under Local State Information Structures. (arXiv:2005.03169v1 [eess.SY]) By arxiv.org Published On :: This paper investigates a class of optimal control problems associated with Markov processes with local state information. The decision-maker has only local access to a subset of a state vector information as often encountered in decentralized control problems in multi-agent systems. Under this information structure, part of the state vector cannot be observed. We leverage ab initio principles and find a new form of Bellman equations to characterize the optimal policies of the control problem under local information structures. The dynamic programming solutions feature a mixture of dynamics associated unobservable state components and the local state-feedback policy based on the observable local information. We further characterize the optimal local-state feedback policy using linear programming methods. To reduce the computational complexity of the optimal policy, we propose an approximate algorithm based on virtual beliefs to find a sub-optimal policy. We show the performance bounds on the sub-optimal solution and corroborate the results with numerical case studies. Full Article
k Fast Mapping onto Census Blocks. (arXiv:2005.03156v1 [cs.DC]) By arxiv.org Published On :: Pandemic measures such as social distancing and contact tracing can be enhanced by rapidly integrating dynamic location data and demographic data. Projecting billions of longitude and latitude locations onto hundreds of thousands of highly irregular demographic census block polygons is computationally challenging in both research and deployment contexts. This paper describes two approaches labeled "simple" and "fast". The simple approach can be implemented in any scripting language (Matlab/Octave, Python, Julia, R) and is easily integrated and customized to a variety of research goals. This simple approach uses a novel combination of hierarchy, sparse bounding boxes, polygon crossing-number, vectorization, and parallel processing to achieve 100,000,000+ projections per second on 100 servers. The simple approach is compact, does not increase data storage requirements, and is applicable to any country or region. The fast approach exploits the thread, vector, and memory optimizations that are possible using a low-level language (C++) and achieves similar performance on a single server. This paper details these approaches with the goal of enabling the broader community to quickly integrate location and demographic data. Full Article
k Optimally Convergent Mixed Finite Element Methods for the Stochastic Stokes Equations. (arXiv:2005.03148v1 [math.NA]) By arxiv.org Published On :: We propose some new mixed finite element methods for the time dependent stochastic Stokes equations with multiplicative noise, which use the Helmholtz decomposition of the driving multiplicative noise. It is known [16] that the pressure solution has a low regularity, which manifests in sub-optimal convergence rates for well-known inf-sup stable mixed finite element methods in numerical simulations, see [10]. We show that eliminating this gradient part from the noise in the numerical scheme leads to optimally convergent mixed finite element methods, and that this conceptual idea may be used to retool numerical methods that are well-known in the deterministic setting, including pressure stabilization methods, so that their optimal convergence properties can still be maintained in the stochastic setting. Computational experiments are also provided to validate the theoretical results and to illustrate the conceptional usefulness of the proposed numerical approach. Full Article
k Evaluation, Tuning and Interpretation of Neural Networks for Meteorological Applications. (arXiv:2005.03126v1 [physics.ao-ph]) By arxiv.org Published On :: Neural networks have opened up many new opportunities to utilize remotely sensed images in meteorology. Common applications include image classification, e.g., to determine whether an image contains a tropical cyclone, and image translation, e.g., to emulate radar imagery for satellites that only have passive channels. However, there are yet many open questions regarding the use of neural networks in meteorology, such as best practices for evaluation, tuning and interpretation. This article highlights several strategies and practical considerations for neural network development that have not yet received much attention in the meteorological community, such as the concept of effective receptive fields, underutilized meteorological performance measures, and methods for NN interpretation, such as synthetic experiments and layer-wise relevance propagation. We also consider the process of neural network interpretation as a whole, recognizing it as an iterative scientist-driven discovery process, and breaking it down into individual steps that researchers can take. Finally, while most work on neural network interpretation in meteorology has so far focused on networks for image classification tasks, we expand the focus to also include networks for image translation. Full Article
k Near-optimal Detector for SWIPT-enabled Differential DF Relay Networks with SER Analysis. (arXiv:2005.03096v1 [cs.IT]) By arxiv.org Published On :: In this paper, we analyze the symbol error rate (SER) performance of the simultaneous wireless information and power transfer (SWIPT) enabled three-node differential decode-and-forward (DDF) relay networks, which adopt the power splitting (PS) protocol at the relay. The use of non-coherent differential modulation eliminates the need for sending training symbols to estimate the instantaneous channel state informations (CSIs) at all network nodes, and therefore improves the power efficiency, as compared with the coherent modulation. However, performance analysis results are not yet available for the state-of-the-art detectors such as the approximate maximum-likelihood detector. Existing works rely on Monte-Carlo simulation to show that there exists an optimal PS ratio that minimizes the overall SER. In this work, we propose a near-optimal detector with linear complexity with respect to the modulation size. We derive an accurate approximate SER expression, based on which the optimal PS ratio can be accurately estimated without requiring any Monte-Carlo simulation. Full Article
k Robust Trajectory and Transmit Power Optimization for Secure UAV-Enabled Cognitive Radio Networks. (arXiv:2005.03091v1 [cs.IT]) By arxiv.org Published On :: Cognitive radio is a promising technology to improve spectral efficiency. However, the secure performance of a secondary network achieved by using physical layer security techniques is limited by its transmit power and channel fading. In order to tackle this issue, a cognitive unmanned aerial vehicle (UAV) communication network is studied by exploiting the high flexibility of a UAV and the possibility of establishing line-of-sight links. The average secrecy rate of the secondary network is maximized by robustly optimizing the UAV's trajectory and transmit power. Our problem formulation takes into account two practical inaccurate location estimation cases, namely, the worst case and the outage-constrained case. In order to solve those challenging non-convex problems, an iterative algorithm based on $mathcal{S}$-Procedure is proposed for the worst case while an iterative algorithm based on Bernstein-type inequalities is proposed for the outage-constrained case. The proposed algorithms can obtain effective suboptimal solutions of the corresponding problems. Our simulation results demonstrate that the algorithm under the outage-constrained case can achieve a higher average secrecy rate with a low computational complexity compared to that of the algorithm under the worst case. Moreover, the proposed schemes can improve the secure communication performance significantly compared to other benchmark schemes. Full Article
k A Multifactorial Optimization Paradigm for Linkage Tree Genetic Algorithm. (arXiv:2005.03090v1 [cs.NE]) By arxiv.org Published On :: Linkage Tree Genetic Algorithm (LTGA) is an effective Evolutionary Algorithm (EA) to solve complex problems using the linkage information between problem variables. LTGA performs well in various kinds of single-task optimization and yields promising results in comparison with the canonical genetic algorithm. However, LTGA is an unsuitable method for dealing with multi-task optimization problems. On the other hand, Multifactorial Optimization (MFO) can simultaneously solve independent optimization problems, which are encoded in a unified representation to take advantage of the process of knowledge transfer. In this paper, we introduce Multifactorial Linkage Tree Genetic Algorithm (MF-LTGA) by combining the main features of both LTGA and MFO. MF-LTGA is able to tackle multiple optimization tasks at the same time, each task learns the dependency between problem variables from the shared representation. This knowledge serves to determine the high-quality partial solutions for supporting other tasks in exploring the search space. Moreover, MF-LTGA speeds up convergence because of knowledge transfer of relevant problems. We demonstrate the effectiveness of the proposed algorithm on two benchmark problems: Clustered Shortest-Path Tree Problem and Deceptive Trap Function. In comparison to LTGA and existing methods, MF-LTGA outperforms in quality of the solution or in computation time. Full Article
k Categorical Vector Space Semantics for Lambek Calculus with a Relevant Modality. (arXiv:2005.03074v1 [cs.CL]) By arxiv.org Published On :: We develop a categorical compositional distributional semantics for Lambek Calculus with a Relevant Modality !L*, which has a limited edition of the contraction and permutation rules. The categorical part of the semantics is a monoidal biclosed category with a coalgebra modality, very similar to the structure of a Differential Category. We instantiate this category to finite dimensional vector spaces and linear maps via "quantisation" functors and work with three concrete interpretations of the coalgebra modality. We apply the model to construct categorical and concrete semantic interpretations for the motivating example of !L*: the derivation of a phrase with a parasitic gap. The effectiveness of the concrete interpretations are evaluated via a disambiguation task, on an extension of a sentence disambiguation dataset to parasitic gap phrase one, using BERT, Word2Vec, and FastText vectors and Relational tensors. Full Article
k Two-Grid Deflated Krylov Methods for Linear Equations. (arXiv:2005.03070v1 [math.NA]) By arxiv.org Published On :: An approach is given for solving large linear systems that combines Krylov methods with use of two different grid levels. Eigenvectors are computed on the coarse grid and used to deflate eigenvalues on the fine grid. GMRES-type methods are first used on both the coarse and fine grids. Then another approach is given that has a restarted BiCGStab (or IDR) method on the fine grid. While BiCGStab is generally considered to be a non-restarted method, it works well in this context with deflating and restarting. Tests show this new approach can be very efficient for difficult linear equations problems. Full Article
k I Always Feel Like Somebody's Sensing Me! A Framework to Detect, Identify, and Localize Clandestine Wireless Sensors. (arXiv:2005.03068v1 [cs.CR]) By arxiv.org Published On :: The increasing ubiquity of low-cost wireless sensors in smart homes and buildings has enabled users to easily deploy systems to remotely monitor and control their environments. However, this raises privacy concerns for third-party occupants, such as a hotel room guest who may be unaware of deployed clandestine sensors. Previous methods focused on specific modalities such as detecting cameras but do not provide a generalizable and comprehensive method to capture arbitrary sensors which may be "spying" on a user. In this work, we seek to determine whether one can walk in a room and detect any wireless sensor monitoring an individual. As such, we propose SnoopDog, a framework to not only detect wireless sensors that are actively monitoring a user, but also classify and localize each device. SnoopDog works by establishing causality between patterns in observable wireless traffic and a trusted sensor in the same space, e.g., an inertial measurement unit (IMU) that captures a user's movement. Once causality is established, SnoopDog performs packet inspection to inform the user about the monitoring device. Finally, SnoopDog localizes the clandestine device in a 2D plane using a novel trial-based localization technique. We evaluated SnoopDog across several devices and various modalities and were able to detect causality 96.6% percent of the time, classify suspicious devices with 100% accuracy, and localize devices to a sufficiently reduced sub-space. Full Article
k Weakly-Supervised Neural Response Selection from an Ensemble of Task-Specialised Dialogue Agents. (arXiv:2005.03066v1 [cs.CL]) By arxiv.org Published On :: Dialogue engines that incorporate different types of agents to converse with humans are popular. However, conversations are dynamic in the sense that a selected response will change the conversation on-the-fly, influencing the subsequent utterances in the conversation, which makes the response selection a challenging problem. We model the problem of selecting the best response from a set of responses generated by a heterogeneous set of dialogue agents by taking into account the conversational history, and propose a emph{Neural Response Selection} method. The proposed method is trained to predict a coherent set of responses within a single conversation, considering its own predictions via a curriculum training mechanism. Our experimental results show that the proposed method can accurately select the most appropriate responses, thereby significantly improving the user experience in dialogue systems. Full Article
k Learning, transferring, and recommending performance knowledge with Monte Carlo tree search and neural networks. (arXiv:2005.03063v1 [cs.LG]) By arxiv.org Published On :: Making changes to a program to optimize its performance is an unscalable task that relies entirely upon human intuition and experience. In addition, companies operating at large scale are at a stage where no single individual understands the code controlling its systems, and for this reason, making changes to improve performance can become intractably difficult. In this paper, a learning system is introduced that provides AI assistance for finding recommended changes to a program. Specifically, it is shown how the evaluative feedback, delayed-reward performance programming domain can be effectively formulated via the Monte Carlo tree search (MCTS) framework. It is then shown that established methods from computational games for using learning to expedite tree-search computation can be adapted to speed up computing recommended program alterations. Estimates of expected utility from MCTS trees built for previous problems are used to learn a sampling policy that remains effective across new problems, thus demonstrating transferability of optimization knowledge. This formulation is applied to the Apache Spark distributed computing environment, and a preliminary result is observed that the time required to build a search tree for finding recommendations is reduced by up to a factor of 10x. Full Article
k Football High: Keeping Up with the Joneses By feedproxy.google.com Published On :: Tue, 10 Dec 2013 00:00:00 EST Competition is steep in games like football. The desire to win often trumps safety. Full Article video
k What Soccer Was Like When Retired Soccer Star Briana Scurry First Started Playing By feedproxy.google.com Published On :: Thu, 23 Jan 2014 00:00:00 EST Soccer great Briana Scurry started playing soccer at 12 on an all boys team and in the goal — the "safest" position for a girl ... Full Article video
k Retired Soccer Star Briana Scurry on What a Concussion Feels Like By feedproxy.google.com Published On :: Thu, 23 Jan 2014 00:00:00 EST After she was hit, retired soccer star Briana Scurry felt off balance, sensitive to light and sound,and felt intense pain in her head and neck. Full Article video
k How Does the IMPACT Baseline Test for Athletes Really Work? By feedproxy.google.com Published On :: Thu, 23 Jan 2014 00:00:00 EST Retired Soccer Star Briana Scurry describes how the computerized baseline test works and how it is used for athletes who have sustained a concussion. Full Article video
k Retired Soccer Star Briana Scurry: "My Brain Was Broken" By feedproxy.google.com Published On :: Thu, 23 Jan 2014 00:00:00 EST Retired soccer star Briana Scurry talks about how all her successes started with her mind and her ability to overcome obstacles. After her injury, she felt lost, broken. Full Article video
k When Retired Soccer Star Briana Scurry Knew Her Career Was Over By feedproxy.google.com Published On :: Thu, 23 Jan 2014 00:00:00 EST After several weeks of not playing because of a concussion and then failing several baseline tests, Briana Scurry became very worried. Full Article video
k Why Retired Soccer Star Briana Scurry Is Speaking Out About Concussion By feedproxy.google.com Published On :: Thu, 23 Jan 2014 00:00:00 EST As someone who had a phenomenal career in professional soccer and that had a career-ending head injury, Briana Scurry knows she can help other female — and male — athletes. Full Article video
k What “Friday Night Tykes” Can Teach Us About Youth Football By feedproxy.google.com Published On :: Wed, 29 Jan 2014 00:00:00 EST Why do some parents and coaches think it's okay to let 9-year-old kids get hit in the head over and over in football practices and games? Full Article page
k Looking at the Risk of Concussion in Sports Head On By feedproxy.google.com Published On :: Wed, 02 Jul 2014 00:00:00 EDT Are sports organizations like FIFA taking concussions in sports seriously enough? Full Article page
k CTE pathology in a neurodegenerative disorders brain bank By feedproxy.google.com Published On :: Thu, 03 Dec 2015 00:00:00 EST Full Article page
k Despite risks, many in small town continue to support youth football By feedproxy.google.com Published On :: Thu, 04 Feb 2016 00:00:00 EST Despite multiple concussions, a high school freshman continues to play football. Will family tradition outweigh the risks? Full Article video
k 24 Must-Know Graphic Design Terms By feedproxy.google.com Published On :: Thu, 19 Sep 2019 13:31:41 +0000 Graphic design is everywhere — it’s used in traditional marketing efforts like billboards and fliers, and more importantly, it’s used in nearly every single digital marketing initiative from web design to social media marketing. If you’re a business that’s working with a digital marketing agency for any number of marketing campaigns (especially web design), it’s […] The post 24 Must-Know Graphic Design Terms appeared first on WebFX Blog. Full Article Web Design
k How Personalized Landing Pages Can Make Your Site More Profitable By feedproxy.google.com Published On :: Fri, 27 Sep 2019 13:00:05 +0000 Personalization is one of the most effective marketing techniques to connect with customers online. While the exact methods are different for every business, adding personalized elements to landing pages is a proven method of driving conversions on your site. But why is it so successful? The simple answer is that personalization shows customers that you […] The post How Personalized Landing Pages Can Make Your Site More Profitable appeared first on WebFX Blog. Full Article Web Design
k Website Redesign Checklist + 7 Handy Website Redesign Tips By feedproxy.google.com Published On :: Fri, 25 Oct 2019 16:34:12 +0000 Does your website feature design straight out of the ’90s and functionality from the stone age? If so, it’s time for an upgrade — and WebFX can help. When it comes to website redesign checklists, we’re at the top of our game, and we know how to get things done. But where do you start […] The post Website Redesign Checklist + 7 Handy Website Redesign Tips appeared first on WebFX Blog. Full Article Web Design
k 10 Helpful Tips for How to Make Your Website More Accessible By feedproxy.google.com Published On :: Tue, 03 Dec 2019 14:00:01 +0000 In this article, we'll explore 10 quick and easy ways to improve your site's accessibility. The post 10 Helpful Tips for How to Make Your Website More Accessible appeared first on WebFX Blog. Full Article Web Design
k Is My WordPress Site Secure? 13 Tips for Locking Down Your WordPress Site By feedproxy.google.com Published On :: Fri, 13 Dec 2019 14:00:57 +0000 WordPress powers 35% of all websites, which makes WordPress sites a go-to target for hackers. If you’re like most WordPress site owners, you’re probably asking the same question: Is my WordPress site secure? While you can’t guarantee site security, you can take several steps to improve and maximize your WordPress security. Keep reading to learn […] The post Is My WordPress Site Secure? 13 Tips for Locking Down Your WordPress Site appeared first on WebFX Blog. Full Article Web Design
k Is My Site Hacked? 6 Ways to Find If Your Site’s Been Hacked By feedproxy.google.com Published On :: Mon, 03 Feb 2020 14:00:36 +0000 The nail biting. The endless coffee. The sleepless nights. You can’t keep it up, but you need to know: Is my site hacked? Good news, you don’t have to stay up all night, grind down your nails, or consume all the coffee in the building to find out if your website has been hacked. You […] The post Is My Site Hacked? 6 Ways to Find If Your Site’s Been Hacked appeared first on WebFX Blog. Full Article Web Design
k Is My Website ADA Compliant? How to Check (and Update) Your Site By feedproxy.google.com Published On :: Tue, 11 Feb 2020 14:00:55 +0000 What do Amazon, Hershey’s, and The Wall Street Journal have in common? They’ve all gotten named in lawsuits related to website accessibility and the Americans with Disabilities Act (ADA). They aren’t alone, either. In 2018, more than 2000 website accessibility lawsuits (a 177% increase from 2017) got filed, emphasizing the increased importance and focus on […] The post Is My Website ADA Compliant? How to Check (and Update) Your Site appeared first on WebFX Blog. Full Article Web Design
k Website Statistics for 2020: 10 Critical Stats to Know for Web Design By feedproxy.google.com Published On :: Fri, 21 Feb 2020 15:18:28 +0000 Are you looking to start 2020 with a fresh web design for your business? If so, you must know what you need to do in 2020 to have a website that drives success for your business. With website statistics for 2020, you can see what to do and what to avoid, which will help you […] The post Website Statistics for 2020: 10 Critical Stats to Know for Web Design appeared first on WebFX Blog. Full Article Web Design
k Study Links Texas Earthquakes to Wastewater Injection By feedproxy.google.com Published On :: Thu, 29 Sep 2016 12:10:28 +0000 By Joel Bahr Berkeley News A new study co-authored by UC Berkeley professor Michael Manga confirms that earthquakes in America’s oil country — including a 4.8 magnitude quake that rocked Texas in 2012 — are being triggered by significant injections … Continue reading → Full Article ET News Fossil Fuels Fracking hydralic fracturing man-made earthquakes
k I Took a COBOL Course and I Liked It By dzone.com Published On :: Tue, 28 Apr 2020 19:51:56 GMT COBOL is in the news again. Millions of people are filing unemployment claims nearly all at once, and the systems to process them are failing. Why? They need to scale to unprecedented levels — they’re written in COBOL, and… we don’t have enough COBOL programmers. Here’s a look at the increase in searches for “COBOL programmers”: Full Article web dev programming finance mainframe cobol
k A Different Approach to Coding With React Hooks By dzone.com Published On :: Wed, 29 Apr 2020 15:03:33 GMT React Hooks, introduced in React 16.8, present us with a fundamentally new approach to coding. Some may think of them as a replacement for lifecycles or classes, however, that would be wrong. Like trying to translate a word from another language, sometimes you’re facing a completely new entity, which seems identical on the surface but is very different semantically and can’t be treated as equivalent. React not only changed the approach from OOP to Functional. The method of rendering has changed in principle. React is now fully built on functions instead of classes. And this has to be understood on a conceptual level. Full Article web dev web development react reactjs react hooks onclick
k Docker Image for ASK and AWS CLI By dzone.com Published On :: Wed, 29 Apr 2020 18:06:12 GMT The purpose of this container is to be able to use the Amazon ASK CLI and Amazon AWS CLI in a Docker container in DevOps pipelines. Note: This is a fork from the martindsouza image with these changes: Full Article tutorial web dev aws node alexa aws cli ask cli
k I Built a VS Code Extension: Ngrok for VS Code By dzone.com Published On :: Wed, 29 Apr 2020 18:15:49 GMT Over the Easter weekend, a four day weekend characterized by lockdowns all over the world, I decided to use the extra time I had at home to start a new project and learn a new skill. By the end of the weekend, I was proud to release my first VSCode extension: ngrok for VSCode. What’s That Now? ngrok is a command-line tool built by Alan Shreve that you can use to expose your localhost server with a publicly available URL. It’s great for sharing access to an application running on your own machine, testing web applications on mobile devices, or testing webhook integrations. For example, I’m a big fan of using ngrok to test my webhooks when I am working with Twilio applications. Full Article tutorial web design and web development typescript extension vscode ngrok