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We establish a correspondence between the dimer model on a bipartite graph and a circle pattern with the combinatorics of that graph, which holds for graphs that are either planar or embedded on the torus. The set of positive face weights on the graph gives a set of global coordinates on the space of circle patterns with embedded dual. Under this correspondence, which extends the previously known isoradial case, the urban renewal (local move for dimer models) is equivalent to the Miquel move (local move for circle patterns). As a consequence the Miquel dynamics on circle patterns is governed by the octahedron recurrence. As special cases of these circle pattern embeddings, we recover harmonic embeddings for resistor networks and sembeddings for the Ising model.
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In this paper, we present a distributionally robust optimization (DRO) approach for the transmission expansion planning (TEP) problem, considering both long and shortterm uncertainties on the system load and renewable generation. Longterm uncertainty is represented on two interrelated levels. At the first level, as is customary in industry applications, the deep uncertainty faced in economic, political, environmental, and technological development is addressed based on plausible visions of longterm future scenarios (trends), traced by current experts beliefs. Subsequently, uncertaintyrelated parameters defining the probability distributions of the uncertain factors are partially refined for each longterm scenario, thereby inducing an ambiguity set. Finally, for each longterm scenario and induced ambiguity set, the inherent risk model for the shortterm uncertainty is described by means of conditional probability distributions. The mathematical problem is formulated as a distribu
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We investigate the asymptotic behavior of eigenfunctions of the Laplacian on Riemannian manifolds. We show that BenjaminiSchramm convergence provides a unified language for the level and eigenvalue aspects of the theory. As a result, we present a mathematically precise formulation of Berry's conjecture for a compact negatively curved manifold and formulate a Berrytype conjecture for sequences of locally symmetric spaces. We prove some weak versions of these conjectures. Using ergodic theory, we also analyze the connections of these conjectures to Quantum Unique Ergodicity.
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We study the energy distribution of harmonic 1forms on a compact hyperbolic Riemann surface $S$ that has a small separating closed geodesic. The result is applied to the question how close the Jacobian torus of $S$ comes to a torus that splits. The aim is to answer this and related questions in terms of geometric data of $S$ such as its injectivity radius and the lengths of geodesics that form a homology basis. This is version 1 of an extended paper in which also non separating small geodesics are considered.
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Local and categorytheoretical entropies associated with an endomorphism of finite length (i.e., with zerodimensional closed fiber) of a commutative Noetherian local ring are compared. Local entropy is shown to be less than or equal to categorytheoretical entropy. The two entropies are shown to be equal when the ring is regular, and also for the Frobenius endomorphism of a complete local ring of positive characteristic. Furthermore, given a flat morphism of CohenMacaulay local rings endowed with compatible endomorphisms of finite length, it is shown that local entropy is "additive". Finally, over a ring that is a homomorphic image of a regular local ring, a formula for local entropy in terms of an asymptotic partial Euler characteristic is given.
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Adinkras are combinatorial objects developed to study supersymmetry representations. Gates et al. introduced the "gadget" as a function of pairs of adinkras, obtaining some mysterious results for $(n=4, k=1)$ adinkras with computeraided computation. Specifically, very few values of the gadget actually appear, suggesting a great deal of symmetry in these objects. In this paper, we compute gadgets symbolically and explain some of these observed phenomena with group theory and combinatorics. Guided by this work, we give some suggestions for generalizations of the gadget to other values of the $n$ and $k$ parameters.
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We consider a family of higherdimensional noncommutative tori, which are twisted analogues of the algebras of continuous functions on ordinary tori, and their Toeplitz extensions. Just as solenoids are inverse limits of tori, our Toeplitz noncommutative solenoids are direct limits of the Toeplitz extensions of noncommutative tori. We consider natural dynamics on these Toeplitz algebras, and compute the equilibrium states for these dynamics. We find a large simplex of equilibrium states at each positive inverse temperature, parametrised by the probability measures on an (ordinary) solenoid.
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In contrast with many other convex optimization classes, stateoftheart semidefinite programming solvers are yet unable to efficiently solve large scale instances. This work aims to reduce this scalability gap by proposing a novel proximal algorithm for solving general semidefinite programming problems. The proposed methodology, based on the primaldual hybrid gradient method, allows the presence of linear inequalities without the need of adding extra slack variables and avoids solving a linear system at each iteration. More importantly, it does simultaneously compute the dual variables associated with the linear constraints. The main contribution of this work is to achieve a substantial speedup by effectively adjusting the proposed algorithm in order to exploit the lowrank property inherent to several semidefinite programming problems. This proposed modification is the key element that allows the operator splitting method to efficiently scale to larger instances. Convergence guaran
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We give a partial solution to a question by Alas, Junqueria and Wilson by proving that under PFA the onepoint compactification of a locally compact, discretely generated and countably tight space is also discretely generated. After this, we study the cardinal number given by the smallest possible character of remote and far sets of separable metrizable spaces. Finally, we prove that in some cases a countable space has far points.
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If $\mathfrak{g} \subseteq \mathfrak{h}$ is an extension of Lie algebras over a field $k$ such that ${\rm dim}_k (\mathfrak{g}) = n$ and ${\rm dim}_k (\mathfrak{h}) = n + m$, then the Galois group ${\rm Gal} \, (\mathfrak{h}/\mathfrak{g})$ is explicitly described as a subgroup of the canonical semidirect product of groups ${\rm GL} (m, \, k) \rtimes {\rm M}_{n\times m} (k)$. An Artin type theorem for Lie algebras is proved: if a group $G$ whose order isinvertible in $k$ acts as automorphisms on a Lie algebra $\mathfrak{h}$, then $\mathfrak{h}$ is isomorphic to a skew crossed product $\mathfrak{h}^G \, \#^{\bullet} \, V$, where $\mathfrak{h}^G$ is the subalgebra of invariants and $V$ is the kernel of the Reynolds operator. The Galois group ${\rm Gal} \,(\mathfrak{h}/\mathfrak{h}^G)$ is also computed, highlighting the difference from the classical Galois theory of fields where the corresponding group is $G$. The counterpart for Lie algebras of Hilbert's Theorem 90 is proved and based on
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D. Bennequin and P. Baudot introduced a cohomological construction adapted to information theory, called 'information cohomology', that characterizes Shannon entropy through a cocycle condition. This text develops the relation between information cohomology and topos theory. We also introduce several new constructions and results. First, we define generalized information structures, as categories of finite random variables related by a notion of extension or refinement; classical and quantum probability spaces appear as models (representations) for these general structures. Generalized information structures form a category with finite products and coproducts. We prove that information cohomology is invariant under isomorphisms of generalized structures. Secondly, we prove that the relativelyfree bar construction gives a projective object for the computation of cohomology. Thirdly, we provide detailed computations of $H^1$ for classical probabilities and describe the degenerate cases.
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For a smooth projective curve, the cycles of subordinate or, more generally, secant divisors to a given linear series are among some of the most studied objects in classical enumerative geometry. We consider the intersection of two such cycles corresponding to secant divisors of two different linear series on the same curve and investigate the validity of the enumerative formulas counting the number of divisors in the intersection. We study some interesting cases, with unexpected transversality properties, and establish a general method to verify when this intersection is empty.
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In this paper, we study gravitational instantons (i.e., complete hyperk\"aler 4manifolds with faster than quadratic curvature decay). We prove three main theorems: 1.Any gravitational instanton must have known endALE, ALF, ALG or ALH. 2.In ALG and ALHnonsplitting cases, it must be biholomorphic to a compact complex elliptic surface minus a divisor. Thus, we confirm a longstanding question of Yau in ALG and ALH cases. 3.In ALFD_k case, it must have an O(4)multiplet.
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We analyze the optimal harvesting problem for an ecosystem of species that experience environmental stochasticity. Our work generalizes the current literature significantly by taking into account nonlinear interactions between species, statedependent prices, and species injections. The key generalization is making it possible to not only harvest, but also `seed' individuals into the ecosystem. This is motivated by how fisheries and certain endangered species are controlled. The harvesting problem becomes finding the optimal harvestingseeding strategy that maximizes the expected total income from the harvest minus the lost income from the species injections. Our analysis shows that new phenomena emerge due to the possibility of species injections. It is wellknown that multidimensional harvesting problems are very hard to tackle. We are able to make progress, by characterizing the value function as a viscosity solution of the associated HamiltonJacobiBellman (HJB) equations. Moreov
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This paper deals with the MonteCarlo methods for evaluating expectations of functionals of solutions to McKeanVlasov Stochastic Differential Equations (MVSDE) with drifts of superlinear growth. We assume that the MVSDE is approximated in the standard manner by means of an interacting particle system and propose two importance sampling (IS) techniques to reduce the variance of the resulting Monte Carlo estimator. In the \emph{complete measure change} approach, the IS measure change is applied simultaneously in the coefficients and in the expectation to be evaluated. In the \emph{decoupling} approach we first estimate the law of the solution in a first set of simulations without measure change and then perform a second set of simulations under the importance sampling measure using the approximate solution law computed in the first step. For both approaches, we use large deviations techniques to identify an optimisation problem for the candidate measure change. The decoupling approac
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The independence polynomial of a graph is the generating polynomial for the number of independent sets of each size. Two graphs are said to be \textit{independence equivalent} if they have equivalent independence polynomials. We extend previous work by showing that independence equivalence class of every odd path has size 1, while the class can contain arbitrarily many graphs for even paths. We also prove that the independence equivalence class of every even cycle consists of two graphs when $n\ge 2$ except the independence equivalence class of $C_6$ which consists of three graphs. The odd case remains open, although, using irreducibility results from algebra, we were able show that for a prime $p \geq 5$ and $n\ge 1$ the independence equivalence class of $C_{p^n}$ consists of only two graphs.
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In this paper, we provide an accessible introduction to the theory of locally convex supermanifolds in the categorical approach. In this setting, a supermanifold is a functor $\mathcal{M}\colon\mathbf{Gr}\to\mathbf{Man}$ from the category of Grassmann algebras to the category of locally convex manifolds that has certain local models, forming something akin to an atlas. We give a mostly selfcontained, concrete definition of supermanifolds along these lines, closing several gaps in the literature on the way. If $\Lambda_n\in\mathbf{Gr}$ is the Grassmann algebra with $n$ generators, we show that $\mathcal{M}_{\Lambda_n}$ has the structure of a so called multilinear bundle over the base manifold $\mathcal{M}_\mathbb{R}$. We use this fact to show that the projective limit $\varprojlim_n\mathcal{M}_{\Lambda_n}$ exists in the category of manifolds. In fact, this gives us a faithful functor $\varprojlim\colon\mathbf{SMan}\to\mathbf{Man}$ from the category of supermanifolds to the category of
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Infinitesimal bialgebras were introduced by Joni and Rota. An infinitesimal bialgebra is at the same time an algebra and coalgebra, in such a way that the comultiplication is a derivation. Twenty years after Joni and Rota, Aguiar introduced the concept of an infinitesimal (nonunitary) Hopf algebra. In this paper we study infinitesimal unitary bialgebras and infinitesimal unitary Hopf algebras, in contrary to Aguiar's approach. Using an infinitesimal version of the Hochschild 1cocycle condition, we prove respectively that a class of decorated planar rooted forests is the free cocycle infinitesimal unitary bialgebra and free cocycle infinitesimal unitary Hopf algebra on a set. As an application, we obtain that the planar rooted forests is the free cocycle infinitesimal unitary Hopf algebra on the empty set.
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Generalising a construction of Falconer, we consider classes of $G_\delta$subsets of $\mathbb{R}^d$ with the property that sets belonging to the class have large Hausdorff dimension and the class is closed under countable intersections. We relate these classes to some inhomogeneous potentials and energies, thereby providing some useful tools to determine if a set belongs to one of the classes. As applications of this theory, we calculate, or at least estimate, the Hausdorff dimension of randomly generated limsupsets, and sets that appear in the setting of shrinking targets in dynamical systems. For instance, we prove that for $\alpha \geq 1$, \[ \mathrm{dim}_\mathrm{H}\, \{ \, y :  T_a^n (x)  y < n^{\alpha} \text{ infinitely often} \, \} = \frac{1}{\alpha}, \] for almost every $x \in [1a,1]$, where $T_a$ is a quadratic map with $a$ in a set of parameters described by Benedicks and Carleson.
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In this paper, we construct a theory of integration of Voevodsky motives over a perfect field $k$, and show that it circumvents some of the complications of motivic integration, leading to new arithmetic and geometric results concerning Kequivalent $k$varieties. One main application is that up to direct summing a common Chow motive, Kequivalent smooth projective $k$varieties have the same $\mathbb{Z}[1/p]$Chow motives ($p$ is the characteristic exponent of $k$), partially answering a conjecture of ChinLung Wang. In addition to generalizing a theorem of Kontsevich on the equality of Hodge numbers of Kequivalent smooth projective complex varieties, we show that such varieties have isomorphic \textit{integral} singular cohomology groups. On the arithmetic side, we show that Kequivalent smooth $k$varieties have isomorphic $\ell$adic Galois representations up to semisimplification. Furthermore, we connect this theory of integration of Voevodsky motives to the existence of motivic
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In this paper, we study an interference alignment (IA) scheme with finite time extension and beamformer selection method with low computational complexity for X channel. An IA scheme with a chain structure by the Latin square is proposed for Kx3 multipleinput multipleoutput (MIMO) X channel. Since the proposed scheme can have a larger set of possible beamformers than the conventional schemes, its performance is improved by the efficient beamformer selection for a given channel. Also, we propose a condition number (CN) based beamformer selection method with low computational complexity and its performance improvement is numerically verified.
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In this paper, we study a new notion of scaled minimaxity for sparse estimation in highdimensional linear regression model. We present more optimistic lower bounds than the one given by the classical minimax theory and hence improve on existing results. We recover sharp results for the global minimaxity as a consequence of our study. Fixing the scale of the signaltonoise ratio, we prove that the estimation error can be much smaller than the global minimax error. We construct a new optimal estimator for the scaled minimax sparse estimation. An optimal adaptive procedure is also described.
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In systems and synthetic biology, much research has focused on the behavior and design of single pathways, while, more recently, experimental efforts have focused on how crosstalk (coupling two or more pathways) or inhibiting molecular function (isolating one part of the pathway) affects systemslevel behavior. However, the theory for tackling these larger systems in general has lagged behind. Here, we analyze how joining networks (e.g., crosstalk) or decomposing networks (e.g., inhibition or knockouts) affects three properties that reaction networks may possessidentifiability (recoverability of parameter values from data), steadystate invariants (relationships among species concentrations at steady state, used in model selection), and multistationarity (capacity for multiple steady states, which correspond to multiple cell decisions). Specifically, we prove results that clarify, for a network obtained by joining two smaller networks, how properties of the smaller networks can b
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We prove a compactness theorem for full Booleanvalued models. As an application, we show that if $T$ is a complete countable theory and $\mathcal{B}$ is a complete Boolean algebra, then $\lambda^+$saturated $\mathcal{B}$valued models of $T$ exist. Moreover, if $\mathcal{U}$ is an ultrafilter on $T$ and $\mathbf{M}$ is a $\lambda^+$saturated $\mathcal{B}$valued model of $T$, then whether or not $\mathbf{M}/\mathcal{U}$ is $\lambda^+$saturated just depends on $\mathcal{U}$ and $T$; we say that $\mathcal{U}$ $\lambda^+$saturates $T$ in this case. We show that Keisler's order can be formulated as follows: $T_0 \trianglelefteq T_1$ if and only if for every cardinal $\lambda$, for every complete Boolean algebra $\mathcal{B}$ with the $\lambda^+$c.c., and for every ultrafilter $\mathcal{U}$ on $\mathcal{B}$, if $\mathcal{U}$ $\lambda^+$saturates $T_1$, then $\mathcal{U}$ $\lambda^+$saturates $T_0$.
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In this paper we consider the large genus asymptotics for two classes of SiegelVeech constants associated with an arbitrary connected stratum $\mathcal{H} (\alpha)$ of Abelian differentials. The first is the saddle connection SiegelVeech constant $c_{\text{sc}}^{m_i, m_j} \big( \mathcal{H} (\alpha) \big)$ counting saddle connections between two distinct, fixed zeros of prescribed orders $m_i$ and $m_j$, and the second is the area SiegelVeech constant $c_{\text{area}} \big( \mathcal{H}(\alpha) \big)$ counting maximal cylinders weighted by area. By combining a combinatorial analysis of explicit formulas of EskinMasurZorich that express these constants in terms of MasurVeech strata volumes, with a recent result for the large genus asymptotics of these volumes, we show that $c_{\text{sc}}^{m_i, m_j} \big( \mathcal{H} (\alpha) \big) = (m_i + 1) (m_j + 1) \big( 1 + o(1) \big)$ and $c_{\text{area}} \big( \mathcal{H}(\alpha) \big) = \frac{1}{2} + o(1)$, both as $\alpha = 2g  2$ tends
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Consider a chordal random curve model on a planar graph, in the scaling limit when a finemesh graph approximates a simplyconnected planar domain. The wellknown precompactness conditions of Kemppainen and Smirnov show that certain "crossing estimates" guarantee the subsequential weak convergence of the random curves in the topology of unparametrized curves, as well as in a topology inherited from curves on the unit disc via conformal maps. We complement this result by proving that proceeding to weak limit commutes with changing topology, i.e., limits of conformal images are conformal images of limits, without imposing any boundary regularity assumptions on the domains where the random curves lie. Treating such rough boundaries becomes necessary, e.g., in convergence proofs to multiple SLEs. The result in this generality has not been explicated before and is not trivial, which we demonstrate by giving warning examples and deducing strong consequences.
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FasterthanNyquist (FTN) signaling is a promising nonorthogonal physical layer transmission technique to improve the spectral efficiency of future communication systems but at the expense of intersymbolinterference (ISI). In this paper, we investigate the detection problem of FTN signaling and formulate the sequence estimation problem of any $M$ary phase shift keying (PSK) FTN signaling as an optimization problem that turns out to be nonconvex and nondeterministic polynomial time (NP)hard to solve. We propose a novel algorithm, based on concepts from semidefinite relaxation (SDR) and Gaussian randomization, to detect any $M$ary PSK FTN signaling in polynomial time complexity regardless of the constellation size $M$ or the ISI length. Simulation results show that the proposed algorithm strikes a balance between the achieved performance and the computational complexity. Additionally, results show the merits of the proposed algorithm in improving the spectral efficiency when compar
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Motivated by problems in percolation theory, we study the following 2player positional game. Let $\Lambda_{m \times n}$ be a rectangular gridgraph with $m$ vertices in each row and $n$ vertices in each column. Two players, Maker and Breaker, play in alternating turns. On each of her turns, Maker claims $p$ (asyet unclaimed) edges of the board $\Lambda_{m \times n}$, while on each of his turns Breaker claims $q$ (asyet unclaimed) edges of the board and destroys them. Maker wins the game if she manages to claim all the edges of a crossing path joining the lefthand side of the board to its righthand side, otherwise Breaker wins. We call this game the $(p,q)$crossing game on $\Lambda_{m \times n}$. Given $m,n\in \mathbb{N}$, for which pairs $(p,q)$ does Maker have a winning strategy for the $(p,q)$crossing game on $\Lambda_{m \times n}$? The $(1,1)$case corresponds exactly to the popular game of Bridgit, which is well understood due to it being a special case of the older Shannon
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We obtain limit theorems for $\Phi(A^p)^{1/p}$ and $(A^p\sigma B)^{1/p}$ as $p\to\infty$ for positive matrices $A,B$, where $\Phi$ is a positive linear map between matrix algebras (in particular, $\Phi(A)=KAK^*$) and $\sigma$ is an operator mean (in particular, the weighted geometric mean), which are considered as certain reciprocal LieTrotter formulas and also a generalization of Kato's limit to the supremum $A\vee B$ with respect to the spectral order.
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We present a sample path dependent measure of causal influence between time series. The proposed causal measure is a random sequence, a realization of which enables identification of specific patterns that give rise to high levels of causal influence. We show that these patterns cannot be identified by existing measures such as directed information (DI). We demonstrate how sequential prediction theory may be leveraged to estimate the proposed causal measure and introduce a notion of regret for assessing the performance of such estimators. We prove a finite sample bound on this regret that is determined by the worst case regret of the sequential predictors used in the estimator. Justification for the proposed measure is provided through a series of examples, simulations, and application to stock market data. Within the context of estimating DI, we show that, because joint Markovicity of a pair of processes does not imply the marginal Markovicity of individual processes, commonly used pl
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Ptychography is a popular imaging technique that combines diffractive imaging with scanning microscopy. The technique consists of a coherent beam that is scanned across an object in a series of overlapping positions, leading to reliable and improved phase reconstruction. Computationally, ptychography is extremely expensive, as ptychographic microscopes allow for large fields to be imaged at high resolution. In this work, we propose a multigridbased optimization framework to reduce the computational burdens of largescale ptychographic phase retrieval. Our proposed method exploits the inherent hierarchical structures in ptychography through tailored restriction and prolongation operators for the object and data domains. Our numerical results show that our proposed scheme accelerates the convergence of its underlying solver and outperforms the stateoftheart method in the optics community.
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Nonconcave maximization has been the subject of much recent study in the optimization and machine learning communities, specifically in deep learning. Recent papers ((Ge \etal 2015, Lee \etal 2017) and references therein) indicate that first order methods work well and avoid saddles points. Results as in (Lee \etal 2017), however, are limited to the \textit{unconstrained} case or for cases where the critical points are in the interior of the feasibility set, which fail to capture some of the most interesting applications. In this paper we focus on \textit{constrained} nonconcave maximization. We analyze a variant of a wellestablished algorithm in machine learning called Multiplicative Weights Update (MWU) for the maximization problem $\max_{\mathbf{x} \in D} P(\mathbf{x})$, where $P$ is nonconcave, twice continuously differentiable and $D$ is a product of simplices. We show that MWU converges almost always for small enough stepsizes to critical points that satisfy the second order
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Many dynamical systems arising in biology and other areas exhibit multistationarity (two or more positive steady states with the same conserved quantities). Although deciding multistationarity for a polynomial dynamical system is an effective question in real algebraic geometry, it is in general difficult to determine whether a given network can give rise to a multistationary system, and if so, to identify witnesses to multistationarity, that is, specific parameter values for which the system exhibits multiple steady states. Here we investigate both problems. First, we build on work of Conradi, Feliu, Mincheva, and Wiuf, who showed that for certain reaction networks whose steady states admit a positive parametrization, multistationarity is characterized by whether a certain "critical function" changes sign. Here, we allow for more general parametrizations, which make it much easier to determine the existence of a sign change. This is particularly simple when the steadystate equations
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The contribution of this paper is twofold: First, we prove existence and uniqueness of the weighted maximum likelihood estimator of the multivariate Student$t$ distribution and propose an efficient algorithm for its computation that we call generalized multivariate myriad filter (GMMF). Second, we use the GMMF in a nonlocal framework for the denoising of images corrupted by different kinds of noise. The resulting method is very flexible and can handle very heavytailed noise such as Cauchy noise, but also also Gaussian or wrapped Cauchy noise.
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U.S. PIRG  a nonprofit that uses grassroots methods to advocate for political change  found that 90 percent of manufacturers it contacted claimed that a third party repair would void its warranty. "PIRG researched the warranty information of 50 companies in the Association of Home Appliance Manufacturers (AHAM)  an industry group of notorious for lobbying to protect is repair monopolies  and found that 45 of them claimed independent repair would void their warranty," Motherboard reports. From the report: PIRG poured over the documentation for 50 companies such as Bissell, Whirlpool, and Panasonic to document their warranty policies. When it couldn't find clear language about warranty and repair, it reached out to the companies via their customer service lines. The overwhelming majority of the companies told PIRG that independent repair would void the warranty. The 1975 MagnusonMoss Warranty Act states that no manufacturer who charges more than $5 for a product can put repair
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In a new video from robotics company Boston Dynamics, which Alphabet sold to SoftBank last year, a robot is shown hopping over a log and then up a series of blocks, an activity called parkour. From a report: In previous videos, the robot did a backflip  now it's leaping over obstacles and climbing up large, uneven stairs with fleetfooted ease. But Atlas wasn't always so graceful. In some of the first videos where Boston Dynamics' robots could walk upright, way back in 2015, Atlas lumbered through the woods, looking like it was narrowly avoiding falling with each step, rather than moving with any kind of purpose.
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An anonymous reader quotes a report from Bleeping Computer: Cryptocurrency miners are now being distributed by a new campaign pretending to be Adobe Flash Player installers. While this is not new, this particular campaign is going the extra mile to appear legitimate by not only installing a miner, but also updating Flash Player as well. In a new malware campaign discovered by Palo Alto Unit 42 researcher Brad Duncan, it was found that a fake Flash Player Trojan not only installed a XMRig miner, but it also automatically updated his installed Flash Player. This real Flash installer was downloaded by the Trojan from Adobe's site. By actually performing an upgrade of the desired program, it makes the user less suspicious and adds further legitimacy that the Trojan was a real Adobe installer for Adobe Flash Player. While Flash Player is now updated, what the victim does not know is that a coinminer was silently installed on the computer and started. Once started, this sample would connect
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Slate's Rachel Withers argues that "tech companies that profit from Wikipedia's extensive database owe Wikimedia a much greater debt." Amazon's Alexa, for example, uses Wikipedia "without credit, contribution, or compensation." The Google Assistant also sources Wikipedia, but they credit the encyclopedia  and other sites  when it uses it as a resource. From the report: Amazon recently donated $1 million to the Wikimedia Endowment, a fund that keeps Wikipedia running, as "part of Amazon's and CEO Jeff Bezos' growing work in philanthropy," according to CNET. It's being framed as a "gift," one that  as Amazon puts it  recognizes their shared vision to "make it easier to share knowledge globally." Obviously, and as alluded to by CNET, $1 million is hardly a magnanimous donation from Amazon and Bezos, the former a trilliondollar company and the latter a man with a net worth of more than $160 billion. But it's not just the fact that this donation is, in the scheme of things, paltry.
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Yesterday, at a routine vote on regulations for selfdriving cars, members of the European Peoples' Party voted down a clause that would protect a vehicle's telemetry so that it couldn't become someone's property. The clause affirmed that "data generated by autonomous transport are automatically generated and are by nature not creative, thus making copyright protection or the right on databases inapplicable." Boing Boing reports: This is data that we will need to evaluate the safety of autonomous vehicles, to finetune their performance, to ensure that they are working as the manufacturer claims  data that will not be public domain (as copyright law dictates), but will instead be someone's exclusive purview, to release or withhold as they see fit. Who will own this data? It's unlikely that it will be the owners of the vehicles. It's already the case that most auto manufacturers use license agreements and DRM to lock up your car so that you can't fix it yourself or take it to an inde
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Facebook is purging hundreds of accounts and pages in the U.S., many of which spread political misinformation, for breaking the company's terms against "inauthentic" content and spam. The Verge reports: The company said in a blog post that 559 pages and 251 accounts would be removed. While the accounts used "sensational political content," Facebook did not say that was the reason for the purge. Instead, the accounts and pages will be taken down after they had "consistently broken" the company's rules against gaming its platform. Facebook noted that many used strategies like posting on fake or multiple accounts to generate traffic, or to inflate their popularity. Still, Facebook noted the proximity to the U.S. midterm elections, and said that networks like the ones it removed today are "increasingly" promoting political content that is "often indistinguishable from legitimate political debate." The company said this was the reason it has turned to "behavior" instead of "content" when se
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We study sequences of conformal deformations of a smooth closed Riemannian manifold of dimension $n$, assuming uniform volume bounds and $L^{n/2}$ bounds on their scalar curvatures. Singularities may appear in the limit. Nevertheless, we show that under such bounds the underlying metric spaces are precompact in the GromovHausdorff topology. Our study is based on the use of $A_\infty$weights from harmonic analysis, and provides geometric controls on the limit spaces thus obtained. Our techniques also show that any conformal deformation of the Euclidean metric on $R^n$ with infinite volume and finite $L^{n/2}$ norm of the scalar curvature satisfies the Euclidean isoperimetric inequality.
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3Dprinted plastic objects can track their own use without any electronics
1011 MIT Technology 725We propose a formula for the enumeration of closed lattice random walks of length $n$ enclosing a given algebraic area. The information is contained in the Kreft coefficients which encode, in the commensurate case, the Hofstadter secular equation for a quantum particle hopping on a lattice coupled to a perpendicular magnetic field. The algebraic area enumeration is possible because it is split in $2^{n/21}$ pieces, each tractable in terms of explicit combinatorial expressions.
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An anonymous reader quotes a report from Bloomberg: Amazon is sweetening the pay for some of its longtime warehouse workers after employees criticized the loss of bonuses and stock awards as part of the company's pledge to boost all wages to at least $15 an hour. The world's largest online retailer grabbed headlines last week with its minimumpay pledge  followed by concerns from veteran workers who feared their compensation would actually decline because the company also eliminated bonuses and stock awards. Amazon said any workers already earning $15 would get raises of $1 per hour. Now, some of those employees are learning their hourly raises will actually be $1.25 an hour. Additionally, Amazon is introducing a new cash bonus of $1,500 to $3,000 for tenure milestones at five, 10, 15 and 20 years. Workers with good attendance in the month of December will also get a $100 bonus, according to the company. "All hourly Operations and Customer Service employees will see an increase in th
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Jeffrey Dastin, reporting for Reuters: Amazon's machinelearning specialists uncovered a big problem: their new recruiting engine did not like women. The team had been building computer programs since 2014 to review job applicants' resumes with the aim of mechanizing the search for top talent, five people familiar with the effort told Reuters. Automation has been key to Amazon's ecommerce dominance, be it inside warehouses or driving pricing decisions. The company's experimental hiring tool used artificial intelligence to give job candidates scores ranging from one to five stars  much like shoppers rate products on Amazon, some of the people said. "Everyone wanted this holy grail," one of the people said. "They literally wanted it to be an engine where I'm going to give you 100 resumes, it will spit out the top five, and we'll hire those." But by 2015, the company realized its new system was not rating candidates for software developer jobs and other technical posts in a genderneut
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Apple is planning a new digital video service that will provide original content free to its device owners, CNBC reported Wednesday. From the report: Apple is preparing a new digital video service that will marry original content and subscription services from legacy media companies, according to people familiar with the matter. Owners of Apple devices, such as the iPhone, iPad and Apple TV will find the stillintheworks service in the preinstalled "TV" application, said the people, who asked not to be named because the details of the project are private. The product will include Appleowned content, which will be free to Apple device owners, and subscription "channels" which will allow customers to sign up for onlineonly services, such as those from HBO and Starz. Apple plans to debut the revamped app early next year, the people said. As Bloomberg reported in May, the subscription channels will essentially copy Amazon's Prime Video Channel Subscriptions. Customers will be able to
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From a report: Within the past four years, Apple has managed to "dramatically reduce" the rate of iPhonerelated repair fraud in its retail stores in China, according to The Information's Wayne Ma. The report is based on interviews with more than a dozen former Apple employees who spoke on condition of anonymity. In 2013, Apple is said to have discovered a highly sophisticated fraud scheme in which organized thieves would buy or steal iPhones, remove valuable components like the processor or logic board, swap in fake components, and return the "broken" iPhones to receive replacements they could resell. From the report: "Thieves would stand outside stores with suitcases full of iPhones with some of the original components stripped out and replaced with inferior parts, two of the people said. The fraudsters would hire people to pretend to be customers to return them, each taking a device to stand in line at the Genius Bar, the people said. Once the phones were swapped, the actors would p
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Japanese retailer Uniqlo in Tokyo's Ariake district has managed to cut 90% of its staff and replace them with robots that are capable of inspecting and sorting the clothing housed there. The automation also allows them to operate 24 hours a day. Quartz reports: The company recently remodeled the existing warehouse with an automated system created in partnership with Daifuku, a provider of material handling systems. Now that the system is running, the company revealed during a walkthrough of the new facility, Uniqlo has been able to cut staff at the warehouse by 90%. The Japan News described how the automation works: "The robotic system is designed to transfer products delivered to the warehouse by truck, read electronic tags attached to the products and confirm their stock numbers and other information. When shipping, the system wraps products placed on a conveyor belt in cardboard and attaches labels to them. Only a small portion of work at the warehouse needs to be done by employees,
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The BBC had to replace live broadcasts with recorded material on its TV news channels for about an hour on Wednesday following a technical glitch. BBC News reports: The News at Six was also presented from the BBC's Millbank studio instead of its usual home of New Broadcasting House. The issue affected OpenMedia, a new computer system rolled out across BBC News outlets over the past six months. OpenMedia supplier Annova has been helping to investigate the fault. Engineers believe they have now addressed the problem. BBC News Home Editor Mark Easton shared on social media that he was rushing across London to the Millbank studio.
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