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China may be slowing iPhone sales worldwide, but Chinese people are driving Apple's App Store business. From a report: China accounted for nearly 50 percent of all app downloads in 2018, pushing the global downloads count to reach a record 194 billion, according to research firm App Annie. China, which is the world's largest smartphone market, also accounted for nearly 40 percent of worldwide consumer spend in apps in 2018, App Annie said in its yearly "State of Mobile" report. (Note: Google Play Store is not available in China.) Global consumer spend in apps reached $101 billion last year, up 75 percent since 2016. And 74 percent of all money spent on apps last year came from games. The battle between Silicon Valley companies and Chinese tech giants generated more than half of total consumer spend in the top 300 parent companies in 2018, the report said. The top company for global consumer spend was China's Tencent, which owns stake in several startups, companies, and games  includi
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A federal appeals court denied the FCC's request to postpone oral arguments in a court battle over the agency's decision to repeal its net neutrality rules. The FCC had asked for the hearing to be postponed since the commission's workforce has largely been furloughed due to the partial government shutdown. The hearing remains set for February 1. The Hill reports: After the FCC repealed the rules requiring internet service providers to treat all web traffic equally in December of 2017, a coalition of consumer groups and state attorneys general sued to reverse the move, arguing that the agency failed to justify it. The FCC asked the threejudge panel from the D.C. Circuit Court of Appeals to delay oral arguments out of "an abundance of caution" due to its lapse of funding. Net neutrality groups opposed the motion, arguing that there is an urgent need to settle the legal questions surrounding the FCC's order.
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We propose a deeplearning approach for the joint MIMO detection and channel decoding problem. Conventional MIMO receivers adopt a modelbased approach for MIMO detection and channel decoding in linear or iterative manners. However, due to the complex MIMO signal model, the optimal solution to the joint MIMO detection and channel decoding problem (i.e., the maximum likelihood decoding of the transmitted codewords from the received MIMO signals) is computationally infeasible. As a practical measure, the current modelbased MIMO receivers all use suboptimal MIMO decoding methods with affordable computational complexities. This work applies the latest advances in deep learning for the design of MIMO receivers. In particular, we leverage deep neural networks (DNN) with supervised training to solve the joint MIMO detection and channel decoding problem. We show that DNN can be trained to give much better decoding performance than conventional MIMO receivers do. Our simulations show that a DN
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Based on the method by [K\"uc95], we give a procedure to list up all complete intersection CalabiYau manifolds with respect to direct sums of irreducible homogeneous vector bundles on Grassmannians for each dimension. In particular, we give a classification of such CalabiYau 3folds and determine their topological invariants. We also give alternative descriptions for some of them.
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This is a short review of the two papers on the $x$space asymptotics of the critical twopoint function $G_{p_c}(x)$ for the longrange models of selfavoiding walk, percolation and the Ising model on $\mathbb{Z}^d$, defined by the translationinvariant powerlaw stepdistribution/coupling $D(x)\proptox^{d\alpha}$ for some $\alpha>0$. Let $S_1(x)$ be the randomwalk Green function generated by $D$. We have shown that $\bullet~~S_1(x)$ changes its asymptotic behavior from Newton ($\alpha>2$) to Riesz ($\alpha<2$), with log correction at $\alpha=2$; $\bullet~~G_{p_c}(x)\sim\frac{A}{p_c}S_1(x)$ as $x\to\infty$ in dimensions higher than (or equal to, if $\alpha=2$) the upper critical dimension $d_c$ (with sufficiently large spreadout parameter $L$). The modeldependent $A$ and $d_c$ exhibit crossover at $\alpha=2$. The keys to the proof are (i) detailed analysis on the underlying random walk to derive sharp asymptotics of $S_1$, (ii) bounds on convolutions of power functio
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In the fight against vectorborne arboviruses, an important strategy of control of epidemic consists in controlling the population of vector, \textit{Aedes} mosquitoes in this case. Among possible actions, two techniques consist in releasing mosquitoes to reduce the size of the population (Sterile Insect Technique) or in replacing the wild population by a population carrying a bacteria, called \textit{Wolbachia}, blocking the transmission of viruses from mosquitoes to human. This paper is concerned with the question of optimizing the release protocol for these two strategies with the aim of getting as close as possible to the objectives. Starting from a mathematical model describing the dynamics of the population, we include the control function and introduce the cost functional for both \textit{population replacement} and \textit{Sterile Insect Technique} problems. Next, we establish some properties of the optimal control and illustrate them with some numerical simulations.
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We study properly immersed ancient solutions of the codimension one mean curvature flow in $n$dimensional Euclidean space, and classify the convex hulls of the subsets of space reached by any such flow. In particular, it follows that any compact convex ancient mean curvature flow can only have a slab, a halfspace or all of space as the closure of its set of reach. The proof proceeds via a bihalfspace theorem (also known as a wedge theorem) for ancient solutions derived from a parabolic OmoriYau maximum principle for ancient mean curvature flows.
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We develop a variational principle between mean dimension theory and rate distortion theory. We consider a minimax problem about the rate distortion dimension with respect to two variables (metrics and measures). We prove that the minimax value is equal to the mean dimension for a dynamical system with the marker property. The proof exhibits a new combination of ergodic theory, rate distortion theory and geometric measure theory. Along the way of the proof, we also show that if a dynamical system has the marker property then it has a metric for which the upper metric mean dimension is equal to the mean dimension.
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[L. Gavruta, Frames for Operators, Appl. comput. Harmon. Anal. 32(2012), 139144] introduced a special kind of frames, named $K$frames, where $K$ is an operator, in Hilbert spaces, is significant in frame theory and has many applications. In this paper, first of all, we have introduced the notion of approximative $K$atomic decomposition in Banach spaces. We gave two characterizations regarding the existence of approximative $K$atomic decompositions in Banach spaces. Also some results on the existence of approximative $K$atomic decompositions are obtained. We discuss several methods to construct approximative $K$atomic decomposition for Banach Spaces. Further, approximative $\mathcal{X}_d$frame and approximative $\mathcal{X}_d$Bessel sequence are introduced and studied. Two necessary conditions are given under which an approximative $\mathcal{X}_d$Bessel sequence and approximative $\mathcal{X}_d$frame give rise to a bounded operator with respect to which there is an approximati
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Radicalization is the process by which people come to adopt increasingly extreme political, social or religious ideologies. When radicalization leads to violence radical thinking becomes a threat to national security. Prevention and deradicalization programs are part of a set of strategies used to combat violent extremism, which are collectively known as Countering Violent Extremism (CVE). Prevention programs seek to stop the radicalization process from occurring and taking hold in the first place. Deradicalization programs work with violent extremists and attempt to alter their extremist beliefs and violent behavior with the aim to reintegrate them into society. In this paper we introduce a simple compartmental model suitable to describe prevention and deradicalization programs. The prevention initiatives are modeled by including a vaccination compartment, while the deradicalization process is modeled by including a treatment compartment. We calculate the basic reproduction number
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We show that if $(K,v_1,v_2)$ is a bivalued NIP field with $v_1$ henselian (resp. thenselian) then $v_1$ and $v_2$ are comparable (resp. dependent). As a consequence Shelah's conjecture for NIP fields implies the henselianity conjecture for NIP fields. Furthermore, the latter conjecture is proved for any field admitting a henselian valuation with a dpminimal residue field.
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In this paper, we extend the fractional Sobolev spaces with variable exponents $W^{s,p(x,y)}$ to include the general fractional case $W^{K,p(x,y)}$, where $p$ is a variable exponent, $s\in (0,1)$ and $K$ is a suitable kernel. We are concerned with some qualitative properties of the space $W^{K,p(x,y)}$ (completeness, reflexivity, separability and density). Moreover, we prove a continuous embedding theorem of these spaces into variable exponent Lebesgue spaces. As an application we establish the existence and uniqueness of a solution for a nonlocal problem involving the nonlocal integrodifferential operator of elliptic type.
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Projective ReedSolomon (PRS) codes are ReedSolomon codes of the maximum possible length q+1. The classification of deep holes received words with maximum possible error distance for PRS codes is an important and difficult problem. In this paper, we use algebraic methods to explicitly construct three classes of deep holes for PRS codes. We show that these three classes completely classify all deep holes of PRS codes with redundancy at most four. Previously, the deep hole classification was only known for PRS codes with redundancy at most three in work arXiv:1612.05447
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A cyclic quadrilateral is called a Brahmagupta quadrilateral if its four sides, the two diagonals and the area are all given by integers. In this paper we consider the hitherto unsolved problem of finding two Brahmagupta quadrilaterals with equal perimeters and equal areas. We obtain two parametric solutions of the problem  the first solution generates examples in which each quadrilateral has two equal sides while the second solution gives quadrilaterals all of whose sides are unequal. We also show how more parametric solutions of the problem may be obtained.
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Inspired by recent work of P.L. Lions on conditional optimal control, we introduce a problem of optimal stopping under bounded rationality: the objective is the expected payoff at the time of stopping, conditioned on another event. For instance, an agent may care only about states where she is still alive at the time of stopping, or a company may condition on not being bankrupt. We observe that conditional optimization is timeinconsistent due to the dynamic change of the conditioning probability and develop an equilibrium approach in the spirit of R. H. Strotz' work for sophisticated agents in discrete time. Equilibria are found to be essentially unique in the case of a finite time horizon whereas an infinite horizon gives rise to nonuniqueness and other interesting phenomena. We also introduce a theory which generalizes the classical Snell envelope approach for optimal stopping by considering a pair of processes with Snelltype properties.
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The early Android Q leaked build we have obtained was built just this week with the February 2019 security patches, and it’s uptodate with Google’s AOSP internal master. That means it has a ton of new Android platform features that you won’t find anywhere publicly, but there are no Google Pixel software customizations nor are there preinstalled Google Play apps or services so I don’t have any new information to share on those fronts. Still, there’s a lot to digest here, so we’ve flashed the build on the Pixel 3 XL to find out what’s new—both on the surfacelevel and underthehood. This article will focus on all the surfacelevel changes we’ve found in Android Q. There’s a lot of good stuff in here, most notably a complete redesign of the permissions user interface, as well as even stricter limitations on what applications can do, such as only granting certain permissions while the application in question is in use. There’s also a systemwide dark mode, hints of a DeXli
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This paper describes connected components of the strata of holomorphic abelian differentials on marked Riemann surfaces with prescribed degrees of zeros. Unlike the case for unmarked Riemann surfaces, we find there can be many connected components, distinguished by roots of the cotangent bundle of the surface. In the course of our investigation we also characterize the images of the fundamental groups of strata inside of the mapping class group. The main techniques of proof are mod r winding numbers and a mapping class grouptheoretic analogue of the Euclidean algorithm.
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In this paper we present some characterizations for quasiarithmetic operator means (among them the arithmetic and harmonic means) on the positive definite cone of the full algebra of Hilbert space operators, and also for the KuboAndo geometric mean on the positive definite cone of a general noncommutative $C^*$algebra.
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We consider a class of maxAR(1) sequences connected with the Kendall convolution. For a large class of step size distributions we prove that the one dimensional distributions of the Kendall random walk with any unit step distribution, are regularly varying. The finite dimensional distributions for Kendall convolutions are given. We prove convergence of a continuous time stochastic process constructed from the Kendall random walk in the finite dimensional distributions sense using regularly varying functions.
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Let $X$ be a ball quasiBanach function space and $H_X(\mathbb{R}^n)$ the associated Hardytype space. In this article, the authors establish the characterizations of $H_X(\mathbb{R}^n)$ via the LittlewoodPaley $g$functions and $g_\lambda^\ast$functions. Moreover, the authors obtain the boundedness of Calder\'onZygmund operators on $H_X(\mathbb{R}^n)$. For the local Hardytype space $h_X(\mathbb{R}^n)$, the authors also obtain the boundedness of $S^0_{1,0}(\mathbb{R}^n)$ pseudodifferential operators on $h_X(\mathbb{R}^n)$ via first establishing the atomic characterization of $h_X(\mathbb{R}^n)$. Furthermore, the characterizations of $h_X(\mathbb{R}^n)$ by means of local molecules and local LittlewoodPaley functions are also given. The results obtained in this article have a wide range of generality and can be applied to the classical Hardy space, the weighted Hardy space, the HerzHardy space, the LorentzHardy space, the MorreyHardy space, the variable Hardy space, the Orliczs
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We consider here the CramerLundberg model based on generalized convolutions. In our model the insurance company invests at least part of its money, have employees, shareholders. The financial situation of the company after paying claims can be even better than before. We compute the ruin probability for $\alpha$convolution case, maximal convolution and the Kendall convolution case, which is formulated in the Williamson transform terms. We also give some new results on the Kendall random walks.
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Graph homomorphisms from the $\mathbb{Z}^d$ lattice to $\mathbb{Z}$ are functions on $\mathbb{Z}^d$ whose gradients equal one in absolute value. These functions are the height functions corresponding to proper $3$colorings of $\mathbb{Z}^d$ and, in two dimensions, corresponding to the $6$vertex model (square ice). We consider the uniform model, obtained by sampling uniformly such a graph homomorphism subject to boundary conditions. Our main result is that the model delocalizes in two dimensions, having no translationinvariant Gibbs measures. Additional results are obtained in higher dimensions and include the fact that every Gibbs measure which is ergodic under even translations is extremal and that these Gibbs measures are stochastically ordered.
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The aim of this thesis is to advance the theory behind quantum information processing tasks, by deriving fundamental limits on bipartite quantum interactions and dynamics, which corresponds to an underlying Hamiltonian that governs the physical transformation of a twobody open quantum system. The goal is to determine entangling abilities of such arbitrary bipartite quantum interactions. Doing so provides fundamental limitations on information processing tasks, including entanglement distillation and secret key generation, over a bipartite quantum network. We also discuss limitations on the entropy change and its rate for dynamics of an open quantum system weakly interacting with the bath. We introduce a measure of nonunitarity to characterize the deviation of a doubly stochastic quantum process from a noiseless evolution. Next, we introduce information processing tasks for secure readout of digital information encoded in readonly memory devices against adversaries of varying capabi
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We derive exact results for the Lindblad equation for a quantum spin chain (onedimensional quantum compass model) with dephasing noise. The system possesses doubly degenerate nonequilibrium steady states due to the presence of a conserved charge commuting with the Hamiltonian and Lindblad operators. We show that the system can be mapped to a nonHermitian Kitaev model on a twoleg ladder, which is solvable by representing the spins in terms of Majorana fermions. This allows us to study the Liouvillian gap, the inverse of relaxation time, in detail. We find that the Liouvillian gap increases monotonically when the dissipation strength $ \gamma $ is small, while it decreases monotonically for large $ \gamma $, implying a kind of phase transition in the first decay mode. The Liouvillian gap and the transition point are obtained in closed form in the case where the spin chain is critical. We also obtain the explicit expression for the autocorrelator of the edge spin. The result implies th
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We obtain the ground state magnetization of the Heisenberg and XXZ spin chains in a magnetic field $h$ as a series in $\sqrt{h_ch}$, where $h_c$ is the smallest field for which the ground state is fully polarized. All the coefficients of the series can be computed in closed form through a recurrence formula that involves only algebraic manipulations. The radius of convergence of the series in the full range $0<h\leq h_c$ is studied numerically. To that end we express the free energy at mean magnetization per site $1/2\leq \langle \sigma^z_i\rangle\leq 1/2$ as a series in $1/2\langle \sigma^z_i\rangle$ whose coefficients can be similarly recursively computed in closed form. This series converges for all $0\leq \langle \sigma^z_i\rangle\leq 1/2$. The recurrence is nothing but the Bethe equations when their roots are written as a double series in their corresponding Bethe number and in $1/2\langle \sigma^z_i\rangle$. It can also be used to derive the corrections in finite size, tha
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We consider those simply connected isothermic surfaces for which their Hopf differential factorizes into a real function and a meromorphic quadratic differential that has a zero or pole at some point, but is nowhere zero and holomorphic otherwise. Upon restriction to a simply connected patch that does not contain the zero or pole, the Darboux and Calapso transformations yield new isothermic surfaces. We determine the limiting behaviour of these transformed patches as the zero or pole of the meromorphic quadratic differential is approached and investigate whether they are continuous around that point.
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We derive two general transformations for certain basic hypergeometric series from the recurrence formulae for the partial numerators and denominators of two $q$continued fractions previously investigated by the authors. By then specializing certain free parameters in these transformations, and employing various identities of RogersRamanujan type, we derive \emph{$m$versions} of these identities. Some of the identities thus found are new, and some have been derived previously by other authors, using different methods. By applying certain transformations due to Watson, Heine and Ramanujan, we derive still more examples of such $m$versions of RogersRamanujantype identities.
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In this paper we study Cauchy problem for thermoelastic plate equations with friction or structural damping in $\mathbb{R}^n$, $n\geq1$, where the heat conduction is modeled by Fourier's law. We explain some qualitative properties of solutions influenced by different damping mechanisms. We show which damping in the model has a dominant influence on smoothing effect, energy estimates, $L^pL^q$ estimates not necessary on the conjugate line, and on diffusion phenomena. Moreover, we derive asymptotic profiles of solutions in a framework of weighted $L^1$ data. In particular, sharp decay estimates for lower bound and upper bound of solutions in the $\dot{H}^s$ norm ($s\geq0$) are shown.
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We study the eigenvalues of the Kohn Laplacian on a closed embedded strictly pseudoconvex CR manifold as functionals on the set of positive oriented contact forms $\mathcal{P}_+$. We show that the functionals are continuous with respect to a natural topology on $\mathcal{P}_+$. Using a simple adaptation of the standard KatoRellich perturbation theory, we prove that the functionals are (onesided) differentiable along 1parameter analytic deformations. We use this differentiability to define the notion of critical contact forms, in a generalized sense, for the functionals. We give a necessary (also sufficient in some situations) condition for a contact form to be critical. Finally, we present explicit examples of critical contact form on both homogeneous and nonhomogeneous CR manifolds.
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Convexification is a core technique in global polynomial optimization. Currently, two different approaches compete in practice and in the literature. First, general approaches rooted in nonlinear programming. They are comparitively cheap from a computational point of view, but typically do not provide good (tight) relaxations with respect to bounds for the original problem. Second, approaches based on sumofsquares and moment relaxations. They are typically computationally expensive, but do provide tight relaxations. In this paper, we embed both kinds of approaches into a unified framework of monomial relaxations. We develop a convexification strategy that allows to trade off the quality of the bounds against computational expenses. Computational experiments show that a combination with a prototype cuttingplane algorithm gives very encouraging results.
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This paper contributes to the mean dimension theory of dynamical systems. We introduce a new concept called mean dimension with potential and develop a variational principle for it. This is a mean dimension analogue of the theory of topological pressure. We consider a minimax problem for the sum of rate distortion dimension and the integral of a potential function. We prove that the minimax value is equal to the mean dimension with potential for a dynamical system having the marker property. The basic idea of the proof is a dynamicalization of geometric measure theory.
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We review the theory of CoGorenstein algebras, which was introduced by Beligiannis in the article "The Homological Theory of Contravariantly Finite Subcategories: Gorenstein Categories, AuslanderBuchweitz Contexts and (Co)Stabilization". We show a connection between CoGorenstein algebras and the Nakayama and Generalized Nakayama conjecture.
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The HelmholtzHodge decomposition (HHD) is applied to the construction of Lyapunov functions. It is shown that if a stability condition is satisfied, such a decomposition can be chosen so that its potential function is a Lyapunov function. In connection with the Lyapunov function, vector fields with strictly orthogonal HHD are analyzed. It is shown that they are a generalization of gradient vector fields and have similar properties. Finally, to examine the limitations of the proposed method, planar vector fields are analyzed.
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Denoising stationary process $(X_i)_{i \in Z}$ corrupted by additive white Gaussian noise is a classic and fundamental problem in information theory and statistical signal processing. Despite considerable progress in designing efficient denoising algorithms, for general analog sources, theoreticallyfounded computationallyefficient methods are yet to be found. For instance in denoising $X^n$ corrupted by noise $Z^n$ as $Y^n=X^n+Z^n$, given the full distribution of $X^n$, a minimum mean square error (MMSE) denoiser needs to compute $E[X^nY^n]$. However, for general sources, computing $E[X^nY^n]$ is computationally very challenging, if not infeasible. In this paper, starting by a Bayesian setup, where the source distribution is fully known, a novel denoising method, namely, quantized maximum a posteriori (QMAP) denoiser, is proposed and its asymptotic performance in the high signal to noise ratio regime is analyzed. Both for memoryless sources, and for structured firstorder Markov s
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The incompressible NavierStokes (NS) equation is known to govern the hydrodynamic limit of essentially any fluid and its rich nonlinear structure has critical implications in both mathematics and physics. The employability of the methods of Riemannian geometry to the study of hydrodynamical flows has been previously explored from a purely mathematical perspective. In this work, we propose a bulk metric in $(p+2)$dimensions with the construction being such that the induced metric is flat on a timelike $r = r_c$ (constant) slice. We then show that the equations of {\it parallel transport} for an appropriately defined bulk velocity vector field along its own direction on this manifold when projected onto the flat timelike hypersurface requires the satisfaction of the incompressible NS equation in $(p+1)$dimensions. Additionally, the incompressibility condition of the fluid arises from a vanishing expansion parameter $\theta$, which is known to govern the convergence (or divergence) of
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We present a self contained tour of the Conley index and some applications. The starting point is the fundamental theorem of dynamical systems, passing through the necessary topological background, with a short stop at the basic properties of the Conley index, and arriving at the construction of connection matrices with a panoramic view of the applications: detect heteroclinic orbits arising in delay differential equations, and partial differential equations of parabolic type. The ride will be filled with examples and pictures.
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Given a closed Riemannian manifold $(N^{n+1},g)$, $n+1 \geq 3$ we prove the compactness of the space of singular, minimal hypersurfaces in $N$ whose volumes are uniformly bounded from above and the $p$th Jacobi eigenvalue $\lambda_p$'s are uniformly bounded from below. This generalizes the results of Sharp and AmbrozioCarlottoSharp in higher dimensions.
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We investigate various block preconditioners for a loworder RaviartThomas discretization of the mixed Poisson problem on adaptive quadrilateral meshes. In addition to standard diagonal and Schur complement preconditioners, we present a dedicated AMG solver for saddle point problems (SPAMG). A key element is a stabilized prolongation operator that couples the flux and scalar components. Our numerical experiments in 2D and 3D show that the SPAMG preconditioner displays nearly meshindependent iteration counts for adaptive meshes and heterogeneous coefficients.
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In this article, we summarize combinatorial description of complete intersection CalabiYau threefolds in Hibi toric varieties. Such CalabiYau threefolds have at worst conifold singularities, and are often smoothable to nonsingular CalabiYau threefolds. We focus on such nonsingular CalabiYau threefolds of Picard number one, and illustrate the calculation of topological invariants, using new motivating examples.
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For a random walk on the integer lattice $\mathbb{Z}$ that is attracted to a strictly stable process with index $\alpha\in (1, 2)$ we obtain the asymptotic form of the transition probability for the walk killed when it hits a finite set. The asymptotic forms obtained are valid uniformly in a natural range of the space and time variables. The situation is relatively simple when the limit stable process has jumps in both positive and negative directions; in the other case when the jumps are one sided rather interesting matters are involved and detailed analyses are necessitated.
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For a cyclic covering map $(\Sigma,K) \to (\Sigma',K')$ between two pairs of a 3manifold and a knot each, we describe the fundamental group $\pi_1(\Sigma \setminus K)$ in terms of $\pi_1(\Sigma' \setminus K')$. As a consequence, we give an alternative proof for the fact that certain knots in $S^3$ cannot be represented as the preimage of any knot in a lens space, which is related to free periods of knots. In our proofs, the subgroup of a group $G$ generated by the commutators and the $p$th power of each element of $G$ plays a key role.
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We’re excited to announce that map and addressrelated searches on DuckDuckGo for mobile and desktop are now powered by Apple’s MapKit JS framework, giving you a valuable combination of mapping and privacy. As one of the first global companies using Apple MapKit JS, we can now offer users improved address searches, additional visual features, enhanced satellite imagery, and continually updated maps already in use on billions of Apple devices worldwide. With this updated integration, Apple Maps are now available both embedded within our private search results for relevant queries, as well as available from the “Maps” tab on any search result page. I’m sure Apple users in San Francisco will be very happy with this news. For me, this means there’s no way I’ll be using DuckDuckGo’s location search and other mapping functions – Apple Maps is entirely unusable in The Netherlands, with severely outdated and faulty maps that are outright da
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An advisory from Harry Sintonen describes several vulnerabilities in the scp clients shipped with OpenSSH, PuTTY, and others. "Many scp clients fail to verify if the objects returned by the scp server match those it asked for. This issue dates back to 1983 and rcp, on which scp is based. A separate flaw in the client allows the target directory attributes to be changed arbitrarily. Finally, two vulnerabilities in clients may allow server to spoof the client output." The outcome is that a hostile (or compromised) server can overwrite arbitrary files on the client side. There do not yet appear to be patches available to address these problems.
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Ryne Hager, writing for AndroidPolice: Late last year, Google decided it was time to crack down on apps requesting SMS and call log permissions. Ostensibly, exceptions would be granted for categories including backups and automation, but as of now, there are still gaps which cover legitimate use cases. While some popular apps like Tasker have successfully secured exemptions, others like Cerberus have not. Instead, they've decided to strip out those permissions or risk facing the wrath of Google's upcoming January 9th banhammer, killing associated functionality and disappointing millions of longtime users to adhere to the Play Store's new policy. The Play Console support page for the applicable set of permissions notifies developers that they can submit what is effectively an application for an exemption, categories for which are listed on the same page. (And that list of exceptions has grown since the original announcement.) Nonetheless, a further set of prohibitions are also includ
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Google has removed 85 Android apps from the official Play Store that security researchers from Trend Micro deemed to contain a common strain of adware. "The 85 apps had been downloaded over nine million times, and one app, in particular, named 'Easy Universal TV Remote,' was downloaded over five million times," reports ZDNet. From the report: While the apps were uploaded on the Play Store from different developer accounts and were signed by different digital certificates, they exhibited similar behaviors and shared the same code, researchers said in a report published today. But besides similarities in their source code, the apps were also visually identical, and were all of the same types, being either games or apps that let users play videos or control their TVs remotely. The first time users ran any of the apps, they would proceed to show fullscreen ads in different steps, asking and reasking users to press various buttons to continue. If the user was persistent and stayed with the
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A new program at DARPA is aimed at creating a machine learning system that can sift through the innumerable events and pieces of media generated every day and identify any threads of connection or narrative in them. It's called KAIROS: Knowledgedirected Artificial Intelligence Reasoning Over Schemas. From a report: "Schema" in this case has a very specific meaning. It's the idea of a basic process humans use to understand the world around them by creating little stories of interlinked events. For instance when you buy something at a store, you know that you generally walk into the store, select an item, bring it to the cashier, who scans it, then you pay in some way, and then leave the store. This "buying something" process is a schema we all recognize, and could of course have schemas within it (selecting a product; payment process) or be part of another schema (gift giving; home cooking). Although these are easily imagined inside our heads, they're surprisingly difficult to define
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Emerging research on digital hoarding  a reluctance to get rid of the digital clutter we accumulate through our work and personal lives  suggests that it can make us feel just as stressed and overwhelmed as physical clutter. From a report: Not to mention the cybersecurity problems it can cause for individuals and businesses and the way it makes finding that one email you need sometimes seem impossible. The term digital hoarding was first used in 2015 in a paper about a man in the Netherlands who took several thousand digital photos each day and spent hours processing them. "He never used or looked at the pictures he had saved, but was convinced that they would be of use in the future," wrote the authors. In a study published earlier this year Neave and his colleagues asked 45 people about how they deal with emails, photos, and other files. The reasons people gave for hanging on to their digital effects varied  including pure laziness, thinking something might come in handy, anx
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Let $\xi : \Omega \times \mathbb{R}^n \to \mathbb{R}$ be zero mean, meansquare continuous, stationary, isotropic Gaussian random field with covariance function $r(x) = \mathbb{E}[\xi(0)\xi(x)]$ and let $G : \mathbb{R} \to \mathbb{R}$ such that $G$ is square integrable with respect to the standard Gaussian measure and is of Hermite rank $d$. The BreuerMajor theorem in it's continuous setting gives that, if $r \in L^d(\mathbb{R}^n)$ and $r(x) \to 0$ as $x \to \infty$, then the finite dimensional distributions of $Z_s(t) = \frac{1}{(2s)^{n/2}} \int_{[st^{1/n},st^{1/n}]^n} \Big[G(\xi(x))  \mathbb{E}[G(\xi(x))]\Big]dx$ converge to that of a scaled Brownian motion as $s \to \infty$. Here we give a proof for the case when $\xi : \Omega \times \mathbb{R}^n \to \mathbb{R}^m$ is a random vector field. We also give conditions for the functional convergence in $C([0,\infty))$ of $Z_s$ to hold along with expression for the asymptotic variance of the second chaos component in the Wiener chaos
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We study a natural generalization of inverse systems of finite regular covering spaces. A limit of such a system is a fibration whose fibres are profinite topological groups. However, as shown in a previous paper (ConnerHerfortPavesic: Some anomalous examples of lifting spaces), there are many fibrations whose fibres are profinite groups, which are far from being inverse limits of coverings. We characterize profinite fibrations among a large class of fibrations and relate the profinite topology on the fundamental group of the base with the action of the fundamental group on the fibre, and develop a version of the Borel construction for fibrations whose fibres are profinite groups.
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We investigate the problem of covert and secret key generation over a discrete memoryless channel model with one way public discussion and in presence of an active warden who can arbitrarily vary its channel and tamper with the main channel when an information symbol is sent. In this scenario, we develop an adaptive protocol that is required to conceal not only the key but also whether a protocol is being implemented. Based on the adversary's actions, this protocol generates a key whose size depends on the adversary's actions. Moreover, for a passive adversary and for some models that we identify, we show that covert secret key generation is possible and characterize the covert secret key capacity in special cases; in particular, the covert secret key capacity is sometimes equal to the covert capacity of the channel, so that secrecy comes ``for free.
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The general theory developed by Ben Yaacov for metric structures provides Fra\"iss\'e limits which are approximately ultrahomogeneous. We show here that this result can be strengthened in the case of relational metric structures. We give an extra condition that guarantees exact ultrahomogenous limits. The condition is quite general. We apply it to stochastic processes, the class of diversities, and its subclass of $L_1$ diversities.
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Peng and Zhong (Acta Math Sci {\bf37B(1)}:6978, 2017) introduced and studied a new subclass of analytic functions as follows: \begin{equation*} \Omega:=\left\{f\in \mathcal{A}:\leftzf'(z)f(z)\right<\frac{1}{2}, z\in \Delta\right\}, \end{equation*} where $\mathcal{A}$ is the class of analytic and normalized functions and $\Delta$ is the open unit disc on the complex plane. The class $\Omega$ is a subclass of the starlike univalent functions. In this paper, we obtain some new results for the class $\Omega$ and improve some results that earlier obtained by Peng and Zhong.
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Deep neural networks have become stateoftheart technology for a wide range of practical machine learning tasks such as image classification, handwritten digit recognition, speech recognition, or game intelligence. This paper develops the fundamental limits of learning in deep neural networks by characterizing what is possible if no constraints on the learning algorithm and the amount of training data are imposed. Concretely, we consider informationtheoretically optimal approximation through deep neural networks with the guiding theme being a relation between the complexity of the function (class) to be approximated and the complexity of the approximating network in terms of connectivity and memory requirements for storing the network topology and the associated quantized weights. The theory we develop educes remarkable universality properties of deep networks. Specifically, deep networks are optimal approximants for vastly different function classes such as affine systems and Gabor
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This is a sequel to the authors' article [BKO]. We consider a hyperbolic knot $K$ in a closed 3manifold $M$ and the cotangent bundle of its complement $M \setminus K$. We equip a hyperbolic metric $h$ with $M \setminus K$ and the induced kinetic energy Hamiltonian $H_h = \frac{1}{2} p_h^2$ and Sasakian almost complex structure $J_h$ with the cotangent bundle $T^*(M \setminus K)$. We consider the conormal $\nu^*T$ of a horotorus $T$, i.e., the cusp crosssection given by a level set of the Busemann function in the cusp end and maps $u: (\Sigma, \partial \Sigma) \to (T^*(M \setminus K), \nu^*T)$ converging to a \emph{nonconstant} Hamiltonian chord of $H_h$ at each puncture of $\Sigma$, a boundarypunctured open Riemann surface of genus zero with boundary. We prove that all nonconstant Hamiltonian chords are transversal and of Morse index 0 relative to the horotorus $T$. As a consequence, we prove that $\widetilde{\mathfrak m}^k = 0$ unless $k \neq 2$ and an $A_\infty$algebra asso
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We classify global bifurcations in generic oneparameter local families of \vfs on $S^2$ with a parabolic cycle. The classification is quite different from the classical results presented in monographs on the bifurcation theory. As a by product we prove that generic families described above are structurally stable.
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Let $f$ be the infinitesimal generator of a oneparameter semigroup $\left\{ F_{t}\right\} _{t\ge0}$ of holomorphic selfmappings of the open unit disk $\Delta$. In this paper we study properties of the family $R$ of resolvents $(I+rf)^{1}:\Delta\to\Delta~ (r\ge0)$ in the spirit of geometric function theory. We discovered, in particular, that $R$ forms an inverse L\"owner chain of hyperbolically convex functions. Moreover, each element of $R$ satisfies the NoshiroWarschawski condition and is a starlike function of order at least $\frac12$,. This, in turn, implies that each element of $R$ is also a holomorphic generator. We mention also quasiconformal extension of an element of $R.$ Finally we study the existence of repelling fixed points of this family.
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