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On Tuesday, Mr. Ballmer plans to make public a database and a report that he and a small army of economists, professors and other professionals have been assembling as part of a stealth startup over the last three years called USAFacts. The database is perhaps the first nonpartisan effort to create a fully integrated look at revenue and spending across federal, state and local governments. Want to know how many police officers are employed in various parts of the country and compare that against crime rates? Want to know how much revenue is brought in from parking tickets and the cost to collect? Want to know what percentage of Americans suffer from diagnosed depression and how much the government spends on it? Thatâs in there. You can slice the numbers in all sorts of ways. This is exactly the kind of thing technology should be used for in a democracy: to provide (relatively) easy insight into otherwise incredibly obtuse and splintered government data. Well done.
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Security updates have been issued by CentOS (libreoffice), Debian (icedove, icu, and imagemagick), Fedora (bind, bind99, ghostscript, libxml2, ming, ntp, proftpd, and qemu), Oracle (bind and libreoffice), Red Hat (bind, qemukvm, and qemukvmrhev), Scientific Linux (bind, libreoffice, and qemukvm), Slackware (minicom), and SUSE (xen).
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The review embargo for the Samsung Galaxy S8 was lifted today, so there's reviews all over the place  and they're all pretty much universally positive, so also kind of uninteresting. An article in The New York Times stood out, though. When a splashy new smartphone hits the market, consumers often weigh whether to place an order right away or to wait and see how others react to the device. But with the Galaxy S8, Samsung's first major smartphone release since the spontaneously combusting Galaxy Note 7 was discontinued last year, there isn't much of a debate. Your best bet is to wait to buy the roughly $750 device  not just for safety reasons, but also because other uncertainties surround it. Since I think you should never rush out and buy a complex and expensive device like a smartphone on release day anyway, this is sage advice. However, it is quite unusual for a major publication to just flatout tell consumers to wait and not buy the latest and greatest new smartphone from Sam
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Former Microsoft CEO Steve Ballmer isn't satisfied with owning the Los Angeles Clippers and teaching at Stanford and USC. On Tuesday, the billionaire announced USAFacts, his new startup that aims to improve political discourse by making government financial data easier to access. A small "army" of economists, professors and other professionals will be looking into and publishing data structured similarly to the 10K filings companies issue each year  expenses, revenues and key metrics pulled from dozens of government data sources and compiled into a single massive collection of tables. From a report on The Verge: The nonpartisan site traces $5.4 trillion in government spending under four categories derived from language in the US Constitution. Defense spending, for example, is categorized under the header "provide for the common defense," while education spending is under "secure the blessing of liberty to ourselves and our prosperity." Spending allocation and revenue sources are eac
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The Outline tells the story of CelebrityNetWorth.com, a website launched in 2008 that tells you how much a celebrity is worth. The site was an instant success, but things have turned sore in the last two years. The creator of the website Brian Warner blames Google for it. From the article: For most of its history, Google was like a librarian. You asked a question, and it guided you to the section of the web where you might find the answer. But over the past five years, Google has been experimenting with being an oracle. Type in a question, and you might see a box at the top of the search results page with the answer in large bold type. [...] In 2014, Warner received an email from Google asking if he would be interested in giving the company access to his data in order to scrape it for Knowledge Graph, for free. He said no, as he feared the traffic would plummet. [...] In February 2016, Google started displaying a Featured Snippet for each of the 25,000 celebrities in the CelebrityNetWo
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To celebrate the Earth Day, Google says it is rolling out what was a twoyear in the making major update to Google Earth. From a report: V9 is designed to run in a Web browser (just Chrome for now), but there's now a standalone home for Google Earth. The Android app has been updated, too (iOS is coming soon). Version 9 puts a big focus on guided tours via the "Voyager" section, which serves as a jumping off point for YouTube videos, 360degree content, Street View, and Google Earth landmarks. The tours are led by scientists and documentarians, with some content produced by wellknown groups like the BBC's Planet Earth team. For kids, there's a Sesame Street muppet section.
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Security updates have been issued by Debian (feh, freetype, and radare2), Fedora (kernel and libsndfile), openSUSE (audiofile, dracut, gstreamer, gstreamerpluginsbad, jasper, libpng15, proftpd, and tigervnc), Oracle (qemukvm), Red Hat (kernel, libreoffice, and qemukvmrhev), and SUSE (bind and tiff).
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An anonymous reader quotes a report from The Guardian: In a bid to court working class voters, Donald Trump will sign an executive order on Tuesday to revamp a temporary visa program used to bring foreign workers to fill jobs in the U.S. The president will use a visit to a manufacturing company in Kenosha, Wisconsin, a crucial state he snatched from Hillary Clinton in the election, to promote his latest "Buy America Hire America" offensive. Trump's executive order will call on government departments to introduce reforms to ensure that H1B visas are awarded to the "most skilled or highest paid applicants," a senior administration official said. The executive order will also call for the "strict enforcement" of laws governing entry to the U.S. of labor from overseas, with a view to creating higher wages and employment rates for U.S. workers. The order will also call on government departments to "take prompt action to crack down on fraud and abuse" in the immigration system, a senior adm
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We establish a new connection between metric Diophantine approximation and the parametric geometry of numbers by proving a variational principle facilitating the computation of the Hausdorff and packing dimensions of many sets of interest in Diophantine approximation. In particular, we show that the Hausdorff and packing dimensions of the set of singular $m\times n$ matrices are both equal to $mn \big(1\frac1{m+n}\big)$, thus proving a conjecture of Kadyrov, Kleinbock, Lindenstrauss, and Margulis (preprint 2014) as well as answering a question of Bugeaud, Cheung, and Chevallier (preprint 2016). We introduce the notion of a $template$, which generalizes the notion of a $rigid$ $system$ (Roy, 2015) to the setting of matrix approximation. Our main theorem takes the following form: for any class of templates $\mathcal F$ closed under finite perturbations, the Hausdorff and packing dimensions of the set of matrices whose successive minima functions are members of $\mathcal F$ (up to finite
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We provide a new proof of the known partial regularity result for the optimal transportation map (Brenier map) between two sets. Contrary to the existing regularity theory for the MongeAmp{\`e}re equation, which is based on the maximum principle, our approach is purely variational. By constructing a competitor on the level of the Eulerian (BenamouBrenier) formulation, we show that locally, the velocity is close to the gradient of a harmonic function provided the transportation cost is small. We then translate back to the Lagrangian description and perform a Campanato iteration to obtain an $\epsilon$regularity result.
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We say a zeroone matrix $A$ avoids another zeroone matrix $P$ if no submatrix of $A$ can be transformed to $P$ by changing some ones to zeros. A fundamental problem is to study the extremal function $ex(n,P)$, the maximum number of nonzero entries in an $n \times n$ zeroone matrix $A$ which avoids $P$. To calculate exact values of $ex(n,P)$ for specific values of $n$, we need containment algorithms which tell us whether a given $n \times n$ matrix $A$ contains a given pattern matrix $P$. In this paper, we present optimal algorithms to determine when an $n \times n$ matrix $A$ contains a given pattern $P$ when $P$ is a column of all ones, an identity matrix, a tuple identity matrix, an $L$shaped pattern, or a cross pattern. These algorithms run in $\Theta(n^2)$ time, which is the lowest possible order a containment algorithm can achieve. When $P$ is a rectangular allones matrix, we also obtain an improved running time algorithm, albeit with a higher order.
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TakagiSugeno (TS) type of polytopic models have been used prominently in the literature to analyze nonlinear systems. With the sector nonlinearity approach, an exact representation of a nonlinear system within a sector could be obtained in a TS form. Hence, a number of observer design strategies have been proposed for nonlinear systems using the TS framework. In this work, a design strategy for adaptive observers is presented for a type of TS systems with unknown parameters. The proposed approach improves upon the existing literature in two folds: reduce the computational burden and provide an algorithmic procedure that would seamlessly connect the state estimation and parameter estimation parts of the observer design. Lyapunov approach is used for the stability analysis and the design procedure. The results are illustrated on a simulation example.
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We discuss a design approach for nonlinear discretetime adaptive observer. This involves transforming a nonlinear system into a quasiLPV (Linear Parameter Varying) polytopic model in TakagiSugeno (TS) form using nonlinear embedding and sector nonlinearity (SNL) transformation. We then develop a discretetime counterpart for a joint state and parameter estimation, based on design strategies developed for continuous time models in the existing literature. The design uses a Lyapunov approach and provides an error bounded by $\mathbb{L}_2$ gain. Based on this strategy, we propose a design for adaptive observers for nonlinear systems whose TS form can have unmeasured premise variables.
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The concept of a $\Gamma$semigroup has been introduced by Mridul Kanti Sen in the Int. Symp., New Delhi, 1981. It is well known that the Green's relations play an essential role in studying the structure of semigroups. In the present paper we deal with an application of $\Gamma$semigroups techniques to the Green's Theorem in an attempt to show the way we pass from semigroups to $\Gamma$semigroups.
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Given a graph $G$, viewed as a loopless symmetric digraph, we study the maximum number of fixed points in a conjunctive boolean network with $G$ as interaction graph. We prove that if $G$ has no induced $C_4$, then this quantity equals both the number of maximal independent sets in $G$ and the maximum number of maximal independent sets among all the graphs obtained from $G$ by contracting some edges. We also prove that, in the general case, it is coNPhard to decide if one of these equalities holds, even if $G$ has a unique induced $C_4$.
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Not all approximations arise from information systems. The problem of fitting approximations, subjected to some rules (and related data), to information systems in a rough scheme of things is known as the \emph{inverse problem}. The inverse problem is more general than the duality (or abstract representation) problems and was introduced by the present author in her earlier papers. From the practical perspective, a few (as opposed to one) theoretical frameworks may be suitable for formulating the problem itself. \emph{Granular operator spaces} have been recently introduced and investigated by the present author in her recent work in the context of antichain based and dialectical semantics for general rough sets. The nature of the inverse problem is examined from numbertheoretic and combinatorial perspectives in a higher order variant of granular operator spaces and some necessary conditions are proved. The results and the novel approach would be useful in a number of unsupervised and s
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We prove the infsup stability of the interior penalty class of discontinuous Galerkin schemes in unbalanced meshdependent norms, under a mesh condition allowing for a general class of meshes, which includes many examples of geometrically graded element neighbourhoods. The infsup condition results in the stability of the interior penalty Ritz projection in $L^2$ as well as, for the first time, quasibest approximations in the $L^2$norm which in turn imply a priori error estimates that do not depend on the global maximum meshsize in that norm. Some numerical experiments are also given.
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By studying an admissible family of branching mechanisms introduced in Li (2014), we obtain a pruning procedure on L\'evy trees. Then we could construct a decreasing L\'evyCRTvalued process $\{{\mathcal T}_t\}$ by pruning L\'evy trees and an analogous process $\{{\mathcal T}^*_t\}$ by pruning a critical L\'evy tree conditioned to be infinite. Under a regular condition on the admissible family of branching mechanisms, we show that the law of $\{{\mathcal T}_t\}$ at the ascension time can be represented by $\{{\mathcal T}^*_t\}$. The results generalize those studied in Abraham and Delmas (2012).
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We present a library autgradalg.lib for the free computer algebra system Singular to compute automorphisms of integral, finitely generated $\mathbb{C}$algebras that are graded pointedly by a finitely generated abelian group. It implements the algorithms developed in 'Computing automorphisms of Mori dream spaces'. We apply the algorithms to Mori dream spaces and investigate the automorphism groups of a series of Fano varieties.
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Faced with saturation of Moore's law and increasing dimension of data, system designers have increasingly resorted to parallel and distributed computing. However, distributed computing is often bottle necked by a small fraction of slow processors called "stragglers" that reduce the speed of computation because the fusion node has to wait for all processors to finish. To combat the effect of stragglers, recent literature introduces redundancy in computations across processors, e.g.,~using repetitionbased strategies or erasure codes. The fusion node can exploit this redundancy by completing the computation using outputs from only a subset of the processors, ignoring the stragglers. In this paper, we propose a novel technique  that we call "ShortDot"  to introduce redundant computations in a coding theory inspired fashion, for computing linear transforms of long vectors. Instead of computing long dot products as required in the original linear transform, we construct a larger number
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Consider a class of nonhomogenous ultraparabolic differential equations with drift terms or lower order terms arising from some physical models, and we prove that weak solutions are H\"{o}lder continuous, which also generalizes the classic results of parabolic equations of second order. The main ingredients are a type of weak Poincar\'{e} inequality satisfied by nonnegative weak subsolutions and Moser iteration.
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Derivation of preference vectors from pairwise comparison matrices may be a crucial step in the modelling of decisionmaking problems. We provide an axiomatic characterization of the Logarithmic Least Squares Method (sometimes called row geometric mean), which has gained popularity because of the unique and simply computable solution as well as a number of favourable theoretical properties. This procedure is shown to be the only one that satisfies correctness in the consistent case  requiring the reproduction of the inducing vector for any consistent matrix  and invariance to consistency reconstruction, that is, independence of the weight vector from an arbitrary multiplication of matrix elements along a 3cycle.
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This paper presents a comparative study of three kinds of ideals in fuzzy order theory: Wideals (based on forward Cauchy nets), Fideals (based on flat fuzzy lower sets) and Gideals (based on irreducible fuzzy lower sets), including their role in connecting fuzzy order with fuzzy topology.
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We have derived an analytical formulation for estimating the volume of geometries enclosed by implicitly defined surfaces. The novelty of this work is due to two aspects. First we provide a general analytical formulation for all twodimensional cases, and for elementary three threedimensional cases by which the volume of general threedimensional cases can be computed. Second, our method addresses the inconsistency issue due to mesh refinement. It is demonstrated by several twodimensional and threedimensional cases that this analytical formulation exhibits 2ndorder accuracy.
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Voskresenskii conjectured that stably rational tori are rational. Klyachko proved this assertion for a wide class of tori by general principles. We reprove Klyachko's result by providing simple explicit birational isomorphisms, and elaborate on some links to torusbased cryptography.
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To each weighted Dirichlet space $\mathcal{D}_p$, $0<p<1$, we associate a family of Morreytype spaces ${\mathcal{D}}_p^{\lambda}$, $0< \lambda < 1$, constructed by imposing growth conditions on the norm of hyperbolic translates of functions. We indicate some of the properties of these spaces, mention the characterization in terms of boundary values, and study integration and multiplication operators on them.
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We consider a free boundary problem on cones depending on a parameter c and study when the free boundary is allowed to pass through the vertex of the cone. We show that when the cone is threedimensional and c is large enough, the free boundary avoids the vertex. We also show that when c is small enough but still positive, the free boundary is allowed to pass through the vertex. This establishes 3 as the critical dimension for which the free boundary may pass through the vertex of a right circular cone. In view of the wellknown connection between areaminimizing surfaces and the free boundary problem under consideration, our result is analogous to a result of Morgan that classifies when an areaminimizing surface on a cone passes through the vertex.
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A multiscale numerical method is proposed for the solution of semilinear elliptic stochastic partial differential equations with localized uncertainties and nonlinearities, the uncertainties being modeled by a set of random parameters. It relies on an overlapping domain decomposition method which introduces several subdomains of interest (called patches) containing the different sources of uncertainties and nonlinearities. An iterative algorithm is then introduced, which requires the solution of a sequence of linear global problems (with deterministic operators and uncertain righthand sides), and nonlinear local problems (with uncertain operators and/or righthand sides) over the patches. Nonlinear local problems are solved using an adaptive samplingbased leastsquares method for the construction of sparse polynomial approximations of local solutions as functions of the random parameters. Consistency, convergence and robustness of the algorithm are proved under general assumptio
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We study conditions under which subcomplexes of a double complex of vector spaces allow to compute the BottChern cohomology. We are especially aimed at studying the BottChern cohomology of special classes of solvmanifolds, namely, complex parallelizable solvmanifolds and solvmanifolds of splitting type. More precisely, we can construct explicit finitedimensional double complexes that allow to compute the BottChern cohomology of compact quotients of complex Lie groups, respectively, of some Lie groups of the type $\mathbb{C}^n\ltimes_\varphi N$ where $N$ is nilpotent. As an application, we compute the BottChern cohomology of the complex parallelizable Nakamura manifold and of the completelysolvable Nakamura manifold. In particular, the latter shows that the property of satisfying the $\partial\overline\partial$Lemma is not stronglyclosed under deformations of the complex structure.
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Google has reached a $7.8 million antitrust settlement with Russian watchdog group FAS. According to BGR, the company will loosen restrictions on Android's builtin search engines to allow for Russian competitors to take a share of the pie. From the report: Android's heavy reliance on Google services is to be expected, but in 2015 the Russian antitrust group  officially the Federal Antimonopoly Service  ruled that Google was breaking the law by forcing users to lean on Google for search. The ruling was the result of a complaint filed by Yandex, a Russian competitor to Google that runs the largest search engine in the country as well as web mail, news, maps, and other services. Google's settlement of the issue comes with the condition that Android will no longer lock down the search engine to Google, and must allow users the ability to change it if they want from within the Chrome web browser. Google will also loosen its exclusivity of the default apps on Android devices sold in Rus
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Many people around the world fear their job will eventually be replaced by a machine, including many Slashdotters. But workers in China may be the most fearful as Asia produces more robots than the rest of the world combined. Last week, a Chinese shipping company, called Shentong Express, showed off a mildlydystopian automated warehouse that reportedly cut its labor costs in half using a fleet of tiny robots, according to the South China Morning Post. Quartz reports: In a video, tiny orange robots made by Hikvision ferry packages around an eastern China warehouse, taking each parcel from a human worker, driving under a scanner, and then dumping the package down a specific chute for it to be shipped. The human's main job in the video appears to be picking up packages and placing them labelup on top of the robot, a task modern robotics is only just starting to put into warehouse production. A spokesperson told the Post that Shentong is using the robot in two of its warehouses, and hope
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This post is about experimenting with imitating and extending the window management concepts from the venerable Plan9, Rio. The backstory and motivation is simply that I've had the need for a smaller and more 'hackable' base than the featureheavy Durden environment for a while, and this seemed like a very nice fit.
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