mp Over-the-Air Computation Systems: Optimization, Analysis and Scaling Laws. (arXiv:1909.00329v2 [cs.IT] UPDATED) By arxiv.org Published On :: For future Internet of Things (IoT)-based Big Data applications (e.g., smart cities/transportation), wireless data collection from ubiquitous massive smart sensors with limited spectrum bandwidth is very challenging. On the other hand, to interpret the meaning behind the collected data, it is also challenging for edge fusion centers running computing tasks over large data sets with limited computation capacity. To tackle these challenges, by exploiting the superposition property of a multiple-access channel and the functional decomposition properties, the recently proposed technique, over-the-air computation (AirComp), enables an effective joint data collection and computation from concurrent sensor transmissions. In this paper, we focus on a single-antenna AirComp system consisting of $K$ sensors and one receiver (i.e., the fusion center). We consider an optimization problem to minimize the computation mean-squared error (MSE) of the $K$ sensors' signals at the receiver by optimizing the transmitting-receiving (Tx-Rx) policy, under the peak power constraint of each sensor. Although the problem is not convex, we derive the computation-optimal policy in closed form. Also, we comprehensively investigate the ergodic performance of AirComp systems in terms of the average computation MSE and the average power consumption under Rayleigh fading channels with different Tx-Rx policies. For the computation-optimal policy, we prove that its average computation MSE has a decay rate of $O(1/sqrt{K})$, and our numerical results illustrate that the policy also has a vanishing average power consumption with the increasing $K$, which jointly show the computation effectiveness and the energy efficiency of the policy with a large number of sensors. Full Article
mp A Shift Selection Strategy for Parallel Shift-Invert Spectrum Slicing in Symmetric Self-Consistent Eigenvalue Computation. (arXiv:1908.06043v2 [math.NA] UPDATED) By arxiv.org Published On :: The central importance of large scale eigenvalue problems in scientific computation necessitates the development of massively parallel algorithms for their solution. Recent advances in dense numerical linear algebra have enabled the routine treatment of eigenvalue problems with dimensions on the order of hundreds of thousands on the world's largest supercomputers. In cases where dense treatments are not feasible, Krylov subspace methods offer an attractive alternative due to the fact that they do not require storage of the problem matrices. However, demonstration of scalability of either of these classes of eigenvalue algorithms on computing architectures capable of expressing massive parallelism is non-trivial due to communication requirements and serial bottlenecks, respectively. In this work, we introduce the SISLICE method: a parallel shift-invert algorithm for the solution of the symmetric self-consistent field (SCF) eigenvalue problem. The SISLICE method drastically reduces the communication requirement of current parallel shift-invert eigenvalue algorithms through various shift selection and migration techniques based on density of states estimation and k-means clustering, respectively. This work demonstrates the robustness and parallel performance of the SISLICE method on a representative set of SCF eigenvalue problems and outlines research directions which will be explored in future work. Full Article
mp Keeping out the Masses: Understanding the Popularity and Implications of Internet Paywalls. (arXiv:1903.01406v4 [cs.CY] UPDATED) By arxiv.org Published On :: Funding the production of quality online content is a pressing problem for content producers. The most common funding method, online advertising, is rife with well-known performance and privacy harms, and an intractable subject-agent conflict: many users do not want to see advertisements, depriving the site of needed funding. Because of these negative aspects of advertisement-based funding, paywalls are an increasingly popular alternative for websites. This shift to a "pay-for-access" web is one that has potentially huge implications for the web and society. Instead of a system where information (nominally) flows freely, paywalls create a web where high quality information is available to fewer and fewer people, leaving the rest of the web users with less information, that might be also less accurate and of lower quality. Despite the potential significance of a move from an "advertising-but-open" web to a "paywalled" web, we find this issue understudied. This work addresses this gap in our understanding by measuring how widely paywalls have been adopted, what kinds of sites use paywalls, and the distribution of policies enforced by paywalls. A partial list of our findings include that (i) paywall use is accelerating (2x more paywalls every 6 months), (ii) paywall adoption differs by country (e.g. 18.75% in US, 12.69% in Australia), (iii) paywalls change how users interact with sites (e.g. higher bounce rates, less incoming links), (iv) the median cost of an annual paywall access is $108 per site, and (v) paywalls are in general trivial to circumvent. Finally, we present the design of a novel, automated system for detecting whether a site uses a paywall, through the combination of runtime browser instrumentation and repeated programmatic interactions with the site. We intend this classifier to augment future, longitudinal measurements of paywall use and behavior. Full Article
mp Asymptotic expansions of eigenvalues by both the Crouzeix-Raviart and enriched Crouzeix-Raviart elements. (arXiv:1902.09524v2 [math.NA] UPDATED) By arxiv.org Published On :: Asymptotic expansions are derived for eigenvalues produced by both the Crouzeix-Raviart element and the enriched Crouzeix--Raviart element. The expansions are optimal in the sense that extrapolation eigenvalues based on them admit a fourth order convergence provided that exact eigenfunctions are smooth enough. The major challenge in establishing the expansions comes from the fact that the canonical interpolation of both nonconforming elements lacks a crucial superclose property, and the nonconformity of both elements. The main idea is to employ the relation between the lowest-order mixed Raviart--Thomas element and the two nonconforming elements, and consequently make use of the superclose property of the canonical interpolation of the lowest-order mixed Raviart--Thomas element. To overcome the difficulty caused by the nonconformity, the commuting property of the canonical interpolation operators of both nonconforming elements is further used, which turns the consistency error problem into an interpolation error problem. Then, a series of new results are obtained to show the final expansions. Full Article
mp An improved exact algorithm and an NP-completeness proof for sparse matrix bipartitioning. (arXiv:1811.02043v2 [cs.DS] UPDATED) By arxiv.org Published On :: We investigate sparse matrix bipartitioning -- a problem where we minimize the communication volume in parallel sparse matrix-vector multiplication. We prove, by reduction from graph bisection, that this problem is $mathcal{NP}$-complete in the case where each side of the bipartitioning must contain a linear fraction of the nonzeros. We present an improved exact branch-and-bound algorithm which finds the minimum communication volume for a given matrix and maximum allowed imbalance. The algorithm is based on a maximum-flow bound and a packing bound, which extend previous matching and packing bounds. We implemented the algorithm in a new program called MP (Matrix Partitioner), which solved 839 matrices from the SuiteSparse collection to optimality, each within 24 hours of CPU-time. Furthermore, MP solved the difficult problem of the matrix cage6 in about 3 days. The new program is on average more than ten times faster than the previous program MondriaanOpt. Benchmark results using the set of 839 optimally solved matrices show that combining the medium-grain/iterative refinement methods of the Mondriaan package with the hypergraph bipartitioner of the PaToH package produces sparse matrix bipartitionings on average within 10% of the optimal solution. Full Article
mp Identifying Compromised Accounts on Social Media Using Statistical Text Analysis. (arXiv:1804.07247v3 [cs.SI] UPDATED) By arxiv.org Published On :: Compromised accounts on social networks are regular user accounts that have been taken over by an entity with malicious intent. Since the adversary exploits the already established trust of a compromised account, it is crucial to detect these accounts to limit the damage they can cause. We propose a novel general framework for discovering compromised accounts by semantic analysis of text messages coming out from an account. Our framework is built on the observation that normal users will use language that is measurably different from the language that an adversary would use when the account is compromised. We use our framework to develop specific algorithms that use the difference of language models of users and adversaries as features in a supervised learning setup. Evaluation results show that the proposed framework is effective for discovering compromised accounts on social networks and a KL-divergence-based language model feature works best. Full Article
mp Compression, inversion, and approximate PCA of dense kernel matrices at near-linear computational complexity. (arXiv:1706.02205v4 [math.NA] UPDATED) By arxiv.org Published On :: Dense kernel matrices $Theta in mathbb{R}^{N imes N}$ obtained from point evaluations of a covariance function $G$ at locations ${ x_{i} }_{1 leq i leq N} subset mathbb{R}^{d}$ arise in statistics, machine learning, and numerical analysis. For covariance functions that are Green's functions of elliptic boundary value problems and homogeneously-distributed sampling points, we show how to identify a subset $S subset { 1 , dots , N }^2$, with $# S = O ( N log (N) log^{d} ( N /epsilon ) )$, such that the zero fill-in incomplete Cholesky factorisation of the sparse matrix $Theta_{ij} 1_{( i, j ) in S}$ is an $epsilon$-approximation of $Theta$. This factorisation can provably be obtained in complexity $O ( N log( N ) log^{d}( N /epsilon) )$ in space and $O ( N log^{2}( N ) log^{2d}( N /epsilon) )$ in time, improving upon the state of the art for general elliptic operators; we further present numerical evidence that $d$ can be taken to be the intrinsic dimension of the data set rather than that of the ambient space. The algorithm only needs to know the spatial configuration of the $x_{i}$ and does not require an analytic representation of $G$. Furthermore, this factorization straightforwardly provides an approximate sparse PCA with optimal rate of convergence in the operator norm. Hence, by using only subsampling and the incomplete Cholesky factorization, we obtain, at nearly linear complexity, the compression, inversion and approximate PCA of a large class of covariance matrices. By inverting the order of the Cholesky factorization we also obtain a solver for elliptic PDE with complexity $O ( N log^{d}( N /epsilon) )$ in space and $O ( N log^{2d}( N /epsilon) )$ in time, improving upon the state of the art for general elliptic operators. Full Article
mp Learning Implicit Text Generation via Feature Matching. (arXiv:2005.03588v1 [cs.CL]) By arxiv.org Published On :: Generative feature matching network (GFMN) is an approach for training implicit generative models for images by performing moment matching on features from pre-trained neural networks. In this paper, we present new GFMN formulations that are effective for sequential data. Our experimental results show the effectiveness of the proposed method, SeqGFMN, for three distinct generation tasks in English: unconditional text generation, class-conditional text generation, and unsupervised text style transfer. SeqGFMN is stable to train and outperforms various adversarial approaches for text generation and text style transfer. Full Article
mp Computing with bricks and mortar: Classification of waveforms with a doped concrete blocks. (arXiv:2005.03498v1 [cs.ET]) By arxiv.org Published On :: We present results showing the capability of concrete-based information processing substrate in the signal classification task in accordance with in materio computing paradigm. As the Reservoir Computing is a suitable model for describing embedded in materio computation, we propose that this type of presented basic construction unit can be used as a source for "reservoir of states" necessary for simple tuning of the readout layer. In that perspective, buildings constructed from computing concrete could function as a highly parallel information processor for smart architecture. We present an electrical characterization of the set of samples with different additive concentrations followed by a dynamical analysis of selected specimens showing fingerprints of memfractive properties. Moreover, on the basis of obtained parameters, classification of the signal waveform shapes can be performed in scenarios explicitly tuned for a given device terminal. Full Article
mp Brain-like approaches to unsupervised learning of hidden representations -- a comparative study. (arXiv:2005.03476v1 [cs.NE]) By arxiv.org Published On :: Unsupervised learning of hidden representations has been one of the most vibrant research directions in machine learning in recent years. In this work we study the brain-like Bayesian Confidence Propagating Neural Network (BCPNN) model, recently extended to extract sparse distributed high-dimensional representations. The saliency and separability of the hidden representations when trained on MNIST dataset is studied using an external classifier, and compared with other unsupervised learning methods that include restricted Boltzmann machines and autoencoders. Full Article
mp Dirichlet spectral-Galerkin approximation method for the simply supported vibrating plate eigenvalues. (arXiv:2005.03433v1 [math.NA]) By arxiv.org Published On :: In this paper, we analyze and implement the Dirichlet spectral-Galerkin method for approximating simply supported vibrating plate eigenvalues with variable coefficients. This is a Galerkin approximation that uses the approximation space that is the span of finitely many Dirichlet eigenfunctions for the Laplacian. Convergence and error analysis for this method is presented for two and three dimensions. Here we will assume that the domain has either a smooth or Lipschitz boundary with no reentrant corners. An important component of the error analysis is Weyl's law for the Dirichlet eigenvalues. Numerical examples for computing the simply supported vibrating plate eigenvalues for the unit disk and square are presented. In order to test the accuracy of the approximation, we compare the spectral-Galerkin method to the separation of variables for the unit disk. Whereas for the unit square we will numerically test the convergence rate for a variable coefficient problem. Full Article
mp Detection and Feeder Identification of the High Impedance Fault at Distribution Networks Based on Synchronous Waveform Distortions. (arXiv:2005.03411v1 [eess.SY]) By arxiv.org Published On :: Diagnosis of high impedance fault (HIF) is a challenge for nowadays distribution network protections. The fault current of a HIF is much lower than that of a normal load, and fault feature is significantly affected by fault scenarios. A detection and feeder identification algorithm for HIFs is proposed in this paper, based on the high-resolution and synchronous waveform data. In the algorithm, an interval slope is defined to describe the waveform distortions, which guarantees a uniform feature description under various HIF nonlinearities and noise interferences. For three typical types of network neutrals, i.e.,isolated neutral, resonant neutral, and low-resistor-earthed neutral, differences of the distorted components between the zero-sequence currents of healthy and faulty feeders are mathematically deduced, respectively. As a result, the proposed criterion, which is based on the distortion relationships between zero-sequence currents of feeders and the zero-sequence voltage at the substation, is theoretically supported. 28 HIFs grounded to various materials are tested in a 10kV distribution networkwith three neutral types, and are utilized to verify the effectiveness of the proposed algorithm. Full Article
mp AutoSOS: Towards Multi-UAV Systems Supporting Maritime Search and Rescue with Lightweight AI and Edge Computing. (arXiv:2005.03409v1 [cs.RO]) By arxiv.org Published On :: Rescue vessels are the main actors in maritime safety and rescue operations. At the same time, aerial drones bring a significant advantage into this scenario. This paper presents the research directions of the AutoSOS project, where we work in the development of an autonomous multi-robot search and rescue assistance platform capable of sensor fusion and object detection in embedded devices using novel lightweight AI models. The platform is meant to perform reconnaissance missions for initial assessment of the environment using novel adaptive deep learning algorithms that efficiently use the available sensors and computational resources on drones and rescue vessel. When drones find potential objects, they will send their sensor data to the vessel to verity the findings with increased accuracy. The actual rescue and treatment operation are left as the responsibility of the rescue personnel. The drones will autonomously reconfigure their spatial distribution to enable multi-hop communication, when a direct connection between a drone transmitting information and the vessel is unavailable. Full Article
mp Joint Prediction and Time Estimation of COVID-19 Developing Severe Symptoms using Chest CT Scan. (arXiv:2005.03405v1 [eess.IV]) By arxiv.org Published On :: With the rapidly worldwide spread of Coronavirus disease (COVID-19), it is of great importance to conduct early diagnosis of COVID-19 and predict the time that patients might convert to the severe stage, for designing effective treatment plan and reducing the clinicians' workloads. In this study, we propose a joint classification and regression method to determine whether the patient would develop severe symptoms in the later time, and if yes, predict the possible conversion time that the patient would spend to convert to the severe stage. To do this, the proposed method takes into account 1) the weight for each sample to reduce the outliers' influence and explore the problem of imbalance classification, and 2) the weight for each feature via a sparsity regularization term to remove the redundant features of high-dimensional data and learn the shared information across the classification task and the regression task. To our knowledge, this study is the first work to predict the disease progression and the conversion time, which could help clinicians to deal with the potential severe cases in time or even save the patients' lives. Experimental analysis was conducted on a real data set from two hospitals with 422 chest computed tomography (CT) scans, where 52 cases were converted to severe on average 5.64 days and 34 cases were severe at admission. Results show that our method achieves the best classification (e.g., 85.91% of accuracy) and regression (e.g., 0.462 of the correlation coefficient) performance, compared to all comparison methods. Moreover, our proposed method yields 76.97% of accuracy for predicting the severe cases, 0.524 of the correlation coefficient, and 0.55 days difference for the converted time. Full Article
mp Causal Paths in Temporal Networks of Face-to-Face Human Interactions. (arXiv:2005.03333v1 [cs.SI]) By arxiv.org Published On :: In a temporal network causal paths are characterized by the fact that links from a source to a target must respect the chronological order. In this article we study the causal paths structure in temporal networks of human face to face interactions in different social contexts. In a static network paths are transitive i.e. the existence of a link from $a$ to $b$ and from $b$ to $c$ implies the existence of a path from $a$ to $c$ via $b$. In a temporal network the chronological constraint introduces time correlations that affects transitivity. A probabilistic model based on higher order Markov chains shows that correlations that can invalidate transitivity are present only when the time gap between consecutive events is larger than the average value and are negligible below such a value. The comparison between the densities of the temporal and static accessibility matrices shows that the static representation can be used with good approximation. Moreover, we quantify the extent of the causally connected region of the networks over time. Full Article
mp A Review of Computer Vision Methods in Network Security. (arXiv:2005.03318v1 [cs.NI]) By arxiv.org Published On :: Network security has become an area of significant importance more than ever as highlighted by the eye-opening numbers of data breaches, attacks on critical infrastructure, and malware/ransomware/cryptojacker attacks that are reported almost every day. Increasingly, we are relying on networked infrastructure and with the advent of IoT, billions of devices will be connected to the internet, providing attackers with more opportunities to exploit. Traditional machine learning methods have been frequently used in the context of network security. However, such methods are more based on statistical features extracted from sources such as binaries, emails, and packet flows. On the other hand, recent years witnessed a phenomenal growth in computer vision mainly driven by the advances in the area of convolutional neural networks. At a glance, it is not trivial to see how computer vision methods are related to network security. Nonetheless, there is a significant amount of work that highlighted how methods from computer vision can be applied in network security for detecting attacks or building security solutions. In this paper, we provide a comprehensive survey of such work under three topics; i) phishing attempt detection, ii) malware detection, and iii) traffic anomaly detection. Next, we review a set of such commercial products for which public information is available and explore how computer vision methods are effectively used in those products. Finally, we discuss existing research gaps and future research directions, especially focusing on how network security research community and the industry can leverage the exponential growth of computer vision methods to build much secure networked systems. Full Article
mp YANG2UML: Bijective Transformation and Simplification of YANG to UML. (arXiv:2005.03292v1 [cs.SE]) By arxiv.org Published On :: Software Defined Networking is currently revolutionizing computer networking by decoupling the network control (control plane) from the forwarding functions (data plane) enabling the network control to become directly programmable and the underlying infrastructure to be abstracted for applications and network services. Next to the well-known OpenFlow protocol, the XML-based NETCONF protocol is also an important means for exchanging configuration information from a management platform and is nowadays even part of OpenFlow. In combination with NETCONF, YANG is the corresponding protocol that defines the associated data structures supporting virtually all network configuration protocols. YANG itself is a semantically rich language, which -- in order to facilitate familiarization with the relevant subject -- is often visualized to involve other experts or developers and to support them by their daily work (writing applications which make use of YANG). In order to support this process, this paper presents an novel approach to optimize and simplify YANG data models to assist further discussions with the management and implementations (especially of interfaces) to reduce complexity. Therefore, we have defined a bidirectional mapping of YANG to UML and developed a tool that renders the created UML diagrams. This combines the benefits to use the formal language YANG with automatically maintained UML diagrams to involve other experts or developers, closing the gap between technically improved data models and their human readability. Full Article
mp 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
mp 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
mp Trains, Games, and Complexity: 0/1/2-Player Motion Planning through Input/Output Gadgets. (arXiv:2005.03192v1 [cs.CC]) By arxiv.org Published On :: We analyze the computational complexity of motion planning through local "input/output" gadgets with separate entrances and exits, and a subset of allowed traversals from entrances to exits, each of which changes the state of the gadget and thereby the allowed traversals. We study such gadgets in the 0-, 1-, and 2-player settings, in particular extending past motion-planning-through-gadgets work to 0-player games for the first time, by considering "branchless" connections between gadgets that route every gadget's exit to a unique gadget's entrance. Our complexity results include containment in L, NL, P, NP, and PSPACE; as well as hardness for NL, P, NP, and PSPACE. We apply these results to show PSPACE-completeness for certain mechanics in Factorio, [the Sequence], and a restricted version of Trainyard, improving prior results. This work strengthens prior results on switching graphs and reachability switching games. Full Article
mp 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
mp 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
mp 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
mp An augmented Lagrangian preconditioner for implicitly-constituted non-Newtonian incompressible flow. (arXiv:2005.03150v1 [math.NA]) By arxiv.org Published On :: We propose an augmented Lagrangian preconditioner for a three-field stress-velocity-pressure discretization of stationary non-Newtonian incompressible flow with an implicit constitutive relation of power-law type. The discretization employed makes use of the divergence-free Scott-Vogelius pair for the velocity and pressure. The preconditioner builds on the work [P. E. Farrell, L. Mitchell, and F. Wechsung, SIAM J. Sci. Comput., 41 (2019), pp. A3073-A3096], where a Reynolds-robust preconditioner for the three-dimensional Newtonian system was introduced. The preconditioner employs a specialized multigrid method for the stress-velocity block that involves a divergence-capturing space decomposition and a custom prolongation operator. The solver exhibits excellent robustness with respect to the parameters arising in the constitutive relation, allowing for the simulation of a wide range of materials. Full Article
mp A Gentle Introduction to Quantum Computing Algorithms with Applications to Universal Prediction. (arXiv:2005.03137v1 [quant-ph]) By arxiv.org Published On :: In this technical report we give an elementary introduction to Quantum Computing for non-physicists. In this introduction we describe in detail some of the foundational Quantum Algorithms including: the Deutsch-Jozsa Algorithm, Shor's Algorithm, Grocer Search, and Quantum Counting Algorithm and briefly the Harrow-Lloyd Algorithm. Additionally we give an introduction to Solomonoff Induction, a theoretically optimal method for prediction. We then attempt to use Quantum computing to find better algorithms for the approximation of Solomonoff Induction. This is done by using techniques from other Quantum computing algorithms to achieve a speedup in computing the speed prior, which is an approximation of Solomonoff's prior, a key part of Solomonoff Induction. The major limiting factors are that the probabilities being computed are often so small that without a sufficient (often large) amount of trials, the error may be larger than the result. If a substantial speedup in the computation of an approximation of Solomonoff Induction can be achieved through quantum computing, then this can be applied to the field of intelligent agents as a key part of an approximation of the agent AIXI. Full Article
mp Evaluating text coherence based on the graph of the consistency of phrases to identify symptoms of schizophrenia. (arXiv:2005.03008v1 [cs.CL]) By arxiv.org Published On :: Different state-of-the-art methods of the detection of schizophrenia symptoms based on the estimation of text coherence have been analyzed. The analysis of a text at the level of phrases has been suggested. The method based on the graph of the consistency of phrases has been proposed to evaluate the semantic coherence and the cohesion of a text. The semantic coherence, cohesion, and other linguistic features (lexical diversity, lexical density) have been taken into account to form feature vectors for the training of a model-classifier. The training of the classifier has been performed on the set of English-language interviews. According to the retrieved results, the impact of each feature on the output of the model has been analyzed. The results obtained can indicate that the proposed method based on the graph of the consistency of phrases may be used in the different tasks of the detection of mental illness. Full Article
mp Computing-in-Memory for Performance and Energy Efficient Homomorphic Encryption. (arXiv:2005.03002v1 [cs.CR]) By arxiv.org Published On :: Homomorphic encryption (HE) allows direct computations on encrypted data. Despite numerous research efforts, the practicality of HE schemes remains to be demonstrated. In this regard, the enormous size of ciphertexts involved in HE computations degrades computational efficiency. Near-memory Processing (NMP) and Computing-in-memory (CiM) - paradigms where computation is done within the memory boundaries - represent architectural solutions for reducing latency and energy associated with data transfers in data-intensive applications such as HE. This paper introduces CiM-HE, a Computing-in-memory (CiM) architecture that can support operations for the B/FV scheme, a somewhat homomorphic encryption scheme for general computation. CiM-HE hardware consists of customized peripherals such as sense amplifiers, adders, bit-shifters, and sequencing circuits. The peripherals are based on CMOS technology, and could support computations with memory cells of different technologies. Circuit-level simulations are used to evaluate our CiM-HE framework assuming a 6T-SRAM memory. We compare our CiM-HE implementation against (i) two optimized CPU HE implementations, and (ii) an FPGA-based HE accelerator implementation. When compared to a CPU solution, CiM-HE obtains speedups between 4.6x and 9.1x, and energy savings between 266.4x and 532.8x for homomorphic multiplications (the most expensive HE operation). Also, a set of four end-to-end tasks, i.e., mean, variance, linear regression, and inference are up to 1.1x, 7.7x, 7.1x, and 7.5x faster (and 301.1x, 404.6x, 532.3x, and 532.8x more energy efficient). Compared to CPU-based HE in a previous work, CiM-HE obtain 14.3x speed-up and >2600x energy savings. Finally, our design offers 2.2x speed-up with 88.1x energy savings compared to a state-of-the-art FPGA-based accelerator. Full Article
mp 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
mp 7 Examples of Great “About Us” Pages By feedproxy.google.com Published On :: Tue, 01 Oct 2019 13:00:45 +0000 Your website serves several important purposes for your company — attracting customers, generating leads, and making sales, just to name a few. And as your home on the Internet, it also needs to explain who you are to the world and why they should choose you over your competitors. However, creating an “About Us” […] The post 7 Examples of Great “About Us” Pages appeared first on WebFX Blog. Full Article Web Design
mp What is a Favicon? [+4 Tips for Creating an Impactful Favicon] By feedproxy.google.com Published On :: Thu, 14 Nov 2019 15:40:14 +0000 When you bookmark pages on the web, it’s challenging to remember the name of the page. As you dive back into your bookmarks to find it, you see a small icon next to the page. You recognize the icon and realize it’s the website you viewed prior. This icon, known as a favicon, is small, […] The post What is a Favicon? [+4 Tips for Creating an Impactful Favicon] appeared first on WebFX Blog. Full Article Web Design
mp Is My WordPress Site ADA Compliant? 3+ Plugins for Finding Out! By feedproxy.google.com Published On :: Sat, 21 Dec 2019 14:00:51 +0000 Did you know that breaking the Americans with Disabilities Act (ADA) can result in a six-figure fine? For every violation, companies can receive a $150,000 fine — and if you have a WordPress site, you could be liable. While WordPress aims to ensure website accessibility, it cannot guarantee it since every site owner customizes the […] The post Is My WordPress Site ADA Compliant? 3+ Plugins for Finding Out! appeared first on WebFX Blog. Full Article Web Design
mp Category Page Design Examples: 6 Category Page Inspirations By feedproxy.google.com Published On :: Sat, 04 Jan 2020 15:36:33 +0000 Dozens of people find your business when looking for a type of product but aren’t sure which product fits their needs best. With a well-designed and organized category page, you’ll help people browse products easier and find what they want. To help you get inspired, let’s take a look at some excellent category page design […] The post Category Page Design Examples: 6 Category Page Inspirations appeared first on WebFX Blog. Full Article Web Design
mp 6 Best CMS Software for Website Development & SMBs By feedproxy.google.com Published On :: Tue, 07 Jan 2020 15:55:11 +0000 Are you looking for a content management system (CMS) that will help you create the digital content you need? With so many options on the market, it’s challenging to know which one is the best CMS software for your business. On this page, we’ll take a look at the six best CMS’s for website development […] The post 6 Best CMS Software for Website Development & SMBs appeared first on WebFX Blog. Full Article Web Design
mp 5 Simple Tips for How to Update Content on Your Website By feedproxy.google.com Published On :: Mon, 13 Jan 2020 21:30:41 +0000 Subscribe to our YouTube channel for the latest in digital marketing! Transcript: Your website isn’t set in stone, so you shouldn’t treat it like it is. Technology and the internet change quickly, and often. You should update your website regularly to keep up with the times. Having an up-to-date and optimized site creates a great […] The post 5 Simple Tips for How to Update Content on Your Website appeared first on WebFX Blog. Full Article Web Design
mp 6 Service Page Web Design Examples to Inspire You By feedproxy.google.com Published On :: Mon, 10 Feb 2020 15:27:24 +0000 Did you know that 75% of opinions on website credibility comes from design? If you want people to look at your services and find you credible, you must invest in web design for services pages to provide your audience with a positive experience. By looking at some web design examples for service pages, you’ll get […] The post 6 Service Page Web Design Examples to Inspire You appeared first on WebFX Blog. Full Article Web Design
mp 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
mp 20 Company Website Designs to Inspire Your Small Business By feedproxy.google.com Published On :: Fri, 14 Feb 2020 15:49:14 +0000 As a small or midsize business (SMB), your company website is often the first touchpoint for potential clients — and you want it to make a great first impression. The secret to hitting home with your audience is to have a sophisticated and lively website design that’s aesthetically pleasing and provides great user experience (UX). […] The post 20 Company Website Designs to Inspire Your Small Business appeared first on WebFX Blog. Full Article Web Design
mp What is Website Conversion? [+5 Ways to Improve Conversions] By feedproxy.google.com Published On :: Fri, 14 Feb 2020 19:45:24 +0000 When you’re trying to grow your business online, you must monitor vital metrics to ensure your business is growing. One important metric is your website’s conversions. Conversions help you determine if you’re driving success with your digital marketing campaigns. So, what is website conversion? How can you improve your website conversion rate? Keep reading to […] The post What is Website Conversion? [+5 Ways to Improve Conversions] appeared first on WebFX Blog. Full Article Web Design
mp Top 6 Company Website Design Templates By feedproxy.google.com Published On :: Sat, 15 Feb 2020 14:11:33 +0000 Are you looking to build a new site for your business? If so, company website design templates can help you create the website you want. With so many templates available, how do you determine which one is best for your business? On this page, we’ll provide you with the top six company website design templates, […] The post Top 6 Company Website Design Templates appeared first on WebFX Blog. Full Article Web Design
mp 5 Magnificent Examples of Websites That Convert Visitors into Customers By feedproxy.google.com Published On :: Fri, 13 Mar 2020 13:09:18 +0000 Need some inspiration to build a high converting website? Websites that convert persuade visitors to become customers. These websites drive more revenue, so if you want to increase your site’s revenue, use these examples of websites that convert as inspiration! We’ll go over what makes for the best converting websites and five examples of websites […] The post 5 Magnificent Examples of Websites That Convert Visitors into Customers appeared first on WebFX Blog. Full Article Web Design
mp Design Patterns Demystified - Template Design Pattern By dzone.com Published On :: Wed, 29 Apr 2020 17:15:35 GMT Welcome to the Design Patterns Demystified (DPD) series, in this edition we are going to discuss Template Design Pattern. So let us understand the why, how, what, and where of Template Design Pattern. The Why Let us understand first, why we need this pattern with the help of an example. Let's you are building a reusable library which is orchestrating the operation of buying an item on an e-commerce platform. Now, irrespective of what you are buying, you will follow the same sequence of steps like building your cart, adding an address, filling in payment details, and then finishing the payment. The details in these steps will vary based on what you are buying, how much you are buying, the delivery address, and the preferred mode of payment, but the complete orchestration of steps remains the same. Full Article design patterns for beginners design patterns uncovered design patterns in java template design pattern
mp The Complete Tutorial on the Top 5 Ways to Query Your Relational Database in JavaScript - Part 2 By dzone.com Published On :: Wed, 29 Apr 2020 20:58:05 GMT Welcome back! In the first part of this series, we looked at a very "low-level" way to interact with a relational database by sending it raw SQL strings and retrieving the results. We created a very simple Express application that we can use as an example and deployed it on Heroku with a Postgres database. In this part, we're going to examine a few libraries which build on top of that foundation, adding layers of abstraction that let you read and manipulate database data in a more "JavaScript-like" way. Full Article javascript tutorial sql heroku orm postgres relational database database tutorial bookshelf
mp Beginners Guide to CSS Flexbox With Examples By dzone.com Published On :: Tue, 05 May 2020 22:35:26 GMT Flexbox is not a single property; it's a complete module that comes with a number of features. In this article, we will look at a complete guide for CSS Flexbox. Before going into detail, I just want to answer why we should use flexbox layout instead of a traditional way of doing layout webpage using display properties, float properties, positional properties Full Article tutorial web dev css / style sheets flexbox
mp Regional summer camps hope the pandemic doesn't put activities on pause, but have backup plans ready if it does By www.inlander.com Published On :: Thu, 30 Apr 2020 04:00:00 -0700 [IMAGE-1]After having their school year totally disrupted by the coronavirus pandemic, a return to some semblance of normalcy come summer is all many school-age kids and their families are looking forward to. For many, this anticipation includes annual summer camp traditions, from sleep-away adventures on the lake to fun-filled day camps for arts, learning or team sports.… Full Article Summer Camps
mp A guide to the Inlander's list of 2020 summer camps By www.inlander.com Published On :: Thu, 30 Apr 2020 04:00:00 -0700 Summer Camps 2020 "Regional Summer Camps Hope the Pandemic Doesn't Put Activities on Pause, But Have Backup Plans Ready if it Does" … Full Article Summer Camps
mp Noah Baumbach's great Marriage Story finds comedy and empathy in the details of a painful divorce By www.inlander.com Published On :: Thu, 05 Dec 2019 01:30:00 -0800 [IMAGE-1] Noah Baumbach's Marriage Story begins as its central marriage is coming to an end. Our two protagonists are fiercely independent, articulate, opinionated creative types: Charlie (Adam Driver) is the director of an avant-garde theater troupe in New York City; Nicole (Scarlett Johansson) is an actress and one of his primary collaborators.… Full Article Film/Film News
mp You might feel anxious watching Uncut Gems, or you might simply be annoyed by one man's bad decisions By www.inlander.com Published On :: Thu, 26 Dec 2019 01:30:00 -0800 Uncut Gems is one of those "his own worst enemy" capers. You know, the kind of movie where you sit there for two hours watching some doofus constantly trip over his own laces — usually figuratively, sometimes literally — on the way to a personal epiphany about how all his bad choices and lack of useful self-awareness have led him to whatever unpleasant place they lead him to.… Full Article Film/Film News
mp Doom's new and improved storyline, Pearl Jams new album and more you need to know By www.inlander.com Published On :: Thu, 26 Mar 2020 01:30:00 -0700 PROPHET OF DOOM… Full Article Culture/Arts & Culture
mp The Fox Theater cancels all events, including Spokane Symphony concerts, through April 10 By www.inlander.com Published On :: Thu, 12 Mar 2020 16:22:00 -0700 As the threat of the Coronavirus spreads throughout the country, public events everywhere are being canceled and postponed for public safety concerns. The Fox Theater is the latest venue to follow suit, closing its doors and canceling all events through April 10.… Full Article Music News
mp With a new compilation from his label CorpoRAT Records, Kris Martin gives his roster of local rockers a sonic platform By www.inlander.com Published On :: Thu, 23 Apr 2020 01:30:00 -0700 When he was putting together the latest compilation CD for his label CorpoRAT Records, Kris Martin had intended to hand out promotional discs at Boise's Treefort Music Festival, where several artists from the Spokane label were scheduled to perform, and then officially release the album in April for Record Store Day.… Full Article Music News