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  • If someone uploads a photo of your face to Facebook, the company usually knows that it's you thanks to facial recognition technology. Now Facebook won't just know it's you -- it'll tell you about the photo, too. From a report: Facebook is expanding its use of facial recognition technology and will now alert people that a friend, or a friend of a friend, uploaded a photo of them, even if they haven't been tagged in the picture. If anyone uploads a profile picture that includes your face, Facebook will alert you of that, too. "We're doing this to prevent people from impersonating others on Facebook," the company wrote on its blog Tuesday.

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  • FDA continues to find safety problems. Homeopaths “hopeful” FDA won’t impede access.

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  • So you can keep track of your online persona.

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    Dynamicland

    12-20 Hacker News 821
  • It’s expected to deliver hormones more effectively than injections or pills.

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    2017: The Year In Robocars

    12-20 IEEE 826

    Promises of self-driving cars are beginning to come due

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  • Marcia Bjornerud looks back on the year in seismic events, from North Korea’s supposed hydrogen-bomb test to Mexico’s twin earthquakes to the underground effects of Hurricanes Harvey and Irma.

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  • Testing suggests that iOS 10.2.1 added this functionality to prevent shutdowns.

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  • Earlier this month a post on social media which suggested that Apple might be deliberately downgrading performance on iPhone models with degraded battery was widely circulated. Benchmark Primate Labs' Geekbench has looked into the matter and is corroborating the claims. From a report: Primate Labs founder John Poole has plotted the kernel density of Geekbench 4 scores for iPhone 6s models running iOS 10.2, iOS 10.2.1, and iOS 11.2, visualizing an apparent link between lower performance and degraded battery health. The charts show that on iOS 10.2, the vast majority of iPhone 6s devices benchmarked similarly in performance. However, Poole explains that the distribution of iPhone 6s scores for iOS 10.2.1 appears multimodal, with one large peak around the average and several smaller peaks around lower scores. In other words, after iOS 10.2.1 was released last January, the performance of a percentage of iPhone 6s devices began to suffer.

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  • FCC would be permanently barred from using Title II authority over broadband.

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  • The European Union was aiming for a "deterrent effect" on Google and other technology giants when it ordered the Android-maker to pay 2.4 billion euros ($2.8 billion) for breaching antitrust law over how it displays shopping ads. From a report: Regulators weighed "the need to ensure that the fine has a sufficiently deterrent effect not only on Google and Alphabet but also on undertakings of a similar size and with similar resources," the European Commission said in a 215-page document laying out details of its seven-year investigation into the company. The "particularly large" revenue of Google's parent, Alphabet, also determined the size of the fine, the EU said. The penalty, levied in June, was more than double an earlier 1 billion-euro fine on Intel and came with a threat of more daily fines for Google if it didn't comply with an order to offer equal treatment to rival shopping-comparison services. Big numbers for big technology names have been a theme for EU Competition Commissione

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  • Able Health is hiring Rails engineers to help doctors improve care

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  • Attackers bypass HTTPS encryption protection by registering new TLS certificate.

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  • Friday night report set off an uproar, but officials say it was “mischaracterization.”

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    How do Ruby and Python profilers work?

    12-19 Hacker News 979

    How do Ruby and Python profilers work?

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  • How traders 'pump and dump' cryptocurrencies

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  • Abandoned rape kits identify over 800 serial rapists in one Michigan county

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  • A funeral home with a drive-thru window opened in Nagano Prefecture on Sunday, allowing mourners to pay their respects without getting out of the car. From a report: The operator of the Aishoden funeral home in Ueda said the service is the first of its kind in Japan. It is primarily aimed at allowing seniors and the disabled to attend funerals but may also be used in the future by people short on time. During a tour Saturday, residents lined up to get a look at the innovative facility, which allows drive-thru mourners to stop their cars next to a window and enter their names and addresses on a device handed over by a waiting receptionist.

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  • A friend of mine died and I didn't know because of algorithms

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    Kaspersky sues DHS over federal blacklist

    12-19 Ars Technica 948

    “It failed to satisfy even the minimum standards of due process.”

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  • Moscow-based anti-virus company Kaspersky Lab sued the Trump administration in U.S. federal court on Monday, arguing that the American government has deprived it of due process rights by banning its software from U.S. government agencies. From a report: The lawsuit is the latest effort by Kaspersky Lab to push back on allegations that the company is vulnerable to Kremlin influence. The Department of Homeland Security in September issued a directive to U.S. civilian agencies ordering them to remove Kaspersky Lab from their computer networks within 90 days. The order came amid mounting concern among U.S. officials that the software could enable Russian espionage and threaten national security. The ban was codified last week when President Donald Trump signed legislation banning Kasperky Lab from use across civilian and military agencies.

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  • Improving my productivity using Pomodoro: takeaways after 2 years of practice

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  • A Look at the Internals of 'Tiered JIT Compilation' in .NET Core

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  • Ian Crouch on Mark Hamill’s redemptive performance as Luke Skywalker in “Star Wars: The Last Jedi.”

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    Four stable kernels

    12-19 LWN 848

    Stable kernels 4.14.7, 4.9.70, 4.4.106, and 3.18.88 have been released. They all contain important fixes and users should upgrade.

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  • A new device uses solar-powered electrolysis to separate hydrogen from seawater without any membranes or pumps

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  • Plus deals on laptops, 4K TVs, the Nvidia Shield, and more.

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  • Design of a silicon quantum computer chip

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  • The Chinese government is blocking foreign companies from mapping its roads in great detail, according to a Financial Times (paywalled) report. The restrictions, which reportedly do not apply to Chinese firms, are being instituted in the name of national security. China is concerned about spying. From a report: China has restricted the recording of geographic information for more than a decade because it believes giving other countries access to that information constitutes a security risk. Geographic surveys can't be performed without permission from the government, and many digital cameras don't record GPS coordinates for geotagging, as they do in other countries, according to Fortune.

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  • “It was Vader who supported govt power over everything said & done on the Internet.”

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  • Our application note describes the techniques and hardware required to characterize E/O and O/E devices, as well as optical components with economies of scale and flexibility not present in current Lightwave Component Analyzer (LCA) designs.

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  • An anonymous reader quotes a report from PBS: U.S. Centers for Disease Control and Prevention director Dr. Brenda Fitzgerald on Sunday addressed a report that President Donald Trump's administration had banned the CDC from using seven words or phrases in next year's budget documents. The terms are "fetus," "transgender," "vulnerable," "entitlement," "diversity," "evidence-based" and "science-based," according to a story first reported on Friday in The Washington Post. But Fitzgerald said in a series of tweets on Sunday said there are "no banned words," while emphasizing the agency's commitment to data-driven science. "CDC has a long-standing history of making public health and budget decisions that are based on the best available science and data and for the benefit of all people -- and we will continue to do so," she said. A group of the agency's policy analysts said senior officials at the CDC informed them about the banned words on Thursday, according to the Post's report. In some c

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    Emily Nussbaum: The Best TV Shows of 2017

    12-19 THE NEW YORKER 997

    Emily Nussbaum writes about her top TV shows from 2017, including “The Leftovers,” “The Deuce,” “Crazy Ex-Girlfriend,” “Broad City,” “Big Little Lies,” and more.

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  • Bundle Phobia: find the cost of adding an npm package to your bundle

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  • Online retail companies should ban the sale of mini mobile phones designed to be smuggled into prisons, said justice secretary David Lidington on Monday. From a report: Often marketed as "Beat the Boss phones", the tiny feature phones can be bought for around $25 to $40 online on sites including Amazon, Ebay and Gumtree. On the inside, they can change hands for up to $670. The phones, which can be as small as lipsticks, are popular with prison inmates due to their discreet size and lack of metal, which allows them to beat metal detectors. Mobile phones are banned in prisons, in part because they allow inmates to continue criminal activities while they're locked up. But around 20,000 phones and SIM cards were seized by prison guards in 2016, with mini mobiles making up around a third of these.

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  • Exploiting Windows 10 in a Local Network with WPAD/PAC and JScript

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    Explore a Model Factory

    12-19 MIT Technology 861

    To help you better understand the potential of Industry 4.0, we decided to bring our model factory to you.

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  • Facebook is cracking down on a new type of clickbait: Posts that ask people to "Like" or share or comment to goose engagement numbers, what Facebook is calling "engagement bait." Their solution? Demote the posts considered to be "engagement bait." Recode reports: Facebook has decided it doesn't like publishers gaming the system this way, and claims users don't like it either."People have told us that they dislike spammy posts on Facebook that goad them into interacting with likes, shares, comments, and other actions," the company wrote on its blog. So starting Monday, posts that Facebook considers to be engagement bait will be pushed down in News Feed. Beginning in a few weeks, publishers and Pages that continue to utilize this tactic will see their reach diminished for all of their posts.

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  • Dynamic Tracing a Pony and Python Program with DTrace

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  • Colly – Fast and Elegant Scraping Framework for Golang

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  • Keras and deep learning on the Raspberry Pi

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    Kernel debugging for newbies

    12-19 Hacker News 929

    Kernel debugging for newbies

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    Gene Editing Could Rewrite the GMO Debate

    12-19 MIT Technology 936

    CRISPR and Talen are giving plant scientists a fast and cheap new way to create genetically modified foods.

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  • We prove that the extension of the double ramification cycle defined by the first-named author (using modifications of the stack of stable curves) coincides with that defined by the last-two named authors (using an extended Brill-Noether locus on suitable compactified universal Jacobians). In particular, in the untwisted case we deduce that both of these extensions coincide with that constructed by Li and Graber-Vakil using a virtual fundamental class on a space of rubber maps.

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  • Some sharp refinements and generalizations of Wilker-Cusa-Huygens's inequalities are proved in this paper.

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  • Kubernetes 1.9: Apps Workloads GA and Expanded Ecosystem

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  • We draw attention to simplifications in the theory of a N\"orlund summation method $(N, p)$ that arise when the series $\sum_{n \geqslant 0} p_n$ is convergent.

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  • FastCompany's harrymcc writes: It's not like there's ever a year that isn't rife with stories about buggy software. But 2017 seems to have had an unusually rich supply of software flaws that fouled up major products -- from Twitter to iOS 11 to the Google Pixel 2 -- in ways that were very noticeable and sometimes even funny. Sample this: A nagging flaw in Google's Play Services software for Android causes Gmail to demand access to "body sensors" before it will let users send email. Android Police's Artem Russakovskii discovers that his Mini is recording audio 24/7 and storing it on Google's servers. I rounded up a bunch of them over at Fast Company.

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  • $G$-deformability of maps into projective space is characterised by the existence of certain Lie algebra valued 1-forms. This characterisation gives a unified way to obtain well known results regarding deformability in different geometries.

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  • We study the topology of small covers from their fundamental groups. We find a way to obtain explicit presentations of the fundamental group of a small cover. Then we use these presentations to study the relations between the fundamental groups of a small cover and its facial submanifolds. In particular, we can determine exactly when a facial submanifold of a small cover is $\pi_1$-injective in terms of some purely combinatorial condition of the underlying simple polytope. In addition, our study reveals some connections between several topological notions for 3-dimensional small covers. This allows us to determine when a 3-dimensional small cover and its regular $Z_2^k$-covering spaces are Haken manifolds.

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  • Richard Brody on the closing of Lincoln Plaza Cinemas, and on the atmosphere for independent films, streaming services, and art-house theatres today.

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  • The paper is devoted to frame expansions in Fr\'echet spaces. First we review some results which concern series expansions in general Fr\'echet spaces via Fr\'echet and General Fr\'echet frames. Then we present some new results on series expansions of tempered distributions and ultradistributions, and the corresponding test functions, via localized frames and coefficients in appropriate sequence spaces.

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  • Given two graphs $H$ and $F$, the maximum possible number of copies of $H$ in an $F$-free graph on $n$ vertices is denoted by $ex(n,H,F)$. We investigate the function $ex(n,H,kF)$, where $kF$ denotes $k$ vertex disjoint copies of a fixed graph $F$. Our results include cases when $F$ is a complete graph, cycle or a complete bipartite graph.

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  • Caching in multi-cell networks faces a well-known dilemma, i.e., to cache same contents among multiple edge nodes to enable transmission cooperation/diversity for higher transmission efficiency, or to cache different contents to enable content diversity for higher cache hit rate. In this work, we introduce a partition-based caching to exploit the tradeoff between transmission diversity and content diversity in a multi-cell edge caching networks with single user only. The performance is characterized by the system average outage probability, which can be viewed as weighted sum between cache hit outage probability and cache miss probability. We show that (i) In the low SNR region, the edge nodes are encouraged to cache more fractions of the most popular files so as to better exploit the transmission diversity for the most popular content; (ii) In the high SNR region, the edge nodes are encouraged to cache more files with less fractions of each so as to better exploit the content diversit

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  • In this paper, a downlink macro-diversity precodingaided spatial modulation (MD-PSM) scheme is proposed, in which two base stations (BSs) communicate simultaneously with a single mobile station (MS). As such, the proposed scheme achieved twice the spectral efficiency of the conventional PSM scheme. To render the demodulation possible, the two signal constellation sets used at the two BSs should be disjoint. Also, since the two BSs use the same spatial dimension, i.e., indices of receive antennas, the Minkowski sum of the two constellation sets should include unrepeated symbols. This is achieved through rotating the constellation set used by the second BS, where the error rate is also minimized. After obtaining the optimal rotation angles for several scenarios, a reduced complexity maximum-likelihood receiver is introduced. For an equal number of transmit and receive antennas of 4 and at a target BER of 10^{-4}, the simulation results show that the proposed MD-PSM scheme outperforms the

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  • In this paper we focus on efficient implementations of the Multivariate Decomposition Method (MDM) for approximating integrals of $\infty$-variate functions. Such $\infty$-variate integrals occur for example as expectations in uncertainty quantification. Starting with the anchored decomposition $f = \sum_{\mathfrak{u}\subset\mathbb{N}} f_\mathfrak{u}$, where the sum is over all finite subsets of $\mathbb{N}$ and each $f_\mathfrak{u}$ depends only on the variables $x_j$ with $j\in\mathfrak{u}$, our MDM algorithm approximates the integral of $f$ by first truncating the sum to some `active set' and then approximating the integral of the remaining functions $f_\mathfrak{u}$ term-by-term using Smolyak or (randomized) quasi-Monte Carlo (QMC) quadratures. The anchored decomposition allows us to compute $f_\mathfrak{u}$ explicitly by function evaluations of $f$. Given the specification of the active set and theoretically derived parameters of the quadrature rules, we exploit structures in both

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  • This paper is devoted to proposing a data-driven approach for electrifying the urban taxi fleet. Specifically, based on the gathered real-time vehicle trajectory data of 39053 taxis in Beijing, we conduct time-series simulations to derive insights on both the configuration of electric taxi fleet and dispatching strategies. The proposed simulation framework accurately models the electric vehicle charging behavior from the aspects of time window, charging demand and availability of unoccupied charges, and further incorporates a centralized and intelligent fleet dispatching platform, which is capable of handling taxi service requests and arranging electric taxis' recharging in real time. To address the impacts of the limited driving range and long battery-recharging time on the electrified fleet's operations efficiency, the dispatching platform integrates the information of customers, taxi drivers and charging stations, and adopts a rule-based approach to achieve multiple objectives, incl

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  • We introduce the notion of a symplectic hopfoid, which is a "groupoid-like" object in the category of symplectic manifolds where morphisms are given by canonical relations. Such groupoid-like objects arise when applying a version of the cotangent functor to the structure maps of a Lie groupoid. We show that such objects are in one-to-one correspondence with symplectic double groupoids, generalizing a result of Zakrzewski concerning symplectic double groups and Hopf algebra objects in the aforementioned category. The proof relies on the fact that one can realize the core of a symplectic double groupoid as a symplectic quotient of the total space. The resulting constructions apply more generally to give a correspondence between double Lie groupoids and groupoid-like objects in the category of smooth manifolds and smooth relations, and we show that the cotangent functor relates the two constructions.

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  • An anonymous reader quotes a report from Ars Technica: U.S. Senate Minority Leader Chuck Schumer (D-N.Y.) said he will force a vote on a bill that would reinstate the Federal Communications Commission's net neutrality rules. Legislation to reverse the repeal "doesn't need the support of the majority leader," Schumer said during a press conference Friday, according to The Hill. "We can bring it to the floor and force a vote. So, there will be a vote to repeal the rule that the FCC passed." The Federal Communications Commission voted to repeal its own net neutrality rules last week, and the repeal will take effect 60 days after it is published in the Federal Register. But Congress can overturn agency actions by invoking the Congressional Review Act (CRA), as it did earlier this year in order to eliminate consumer broadband privacy protections. A successful CRA vote in this case would invalidate the FCC's net neutrality repeal and prevent the FCC from issuing a similar repeal in the futur

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  • This paper introduces an elliptic quasi-variational inequality (QVI) problem class with fractional diffusion of order $s \in (0,1)$, studies existence and uniqueness of solutions and develops a solution algorithm. As the fractional diffusion prohibits the use of standard tools to approximate the QVI, instead we realize it as a Dirichlet-to-Neumann map for a problem posed on a semi-infinite cylinder. We first study existence and uniqueness of solutions for this extended QVI and then transfer the results to the fractional QVI: This introduces a new paradigm in the field of fractional QVIs. Further, we truncate the semi-infinite cylinder and show that the solution to the truncated problem converges to the solution of the extended problem, under fairly mild assumptions, as the truncation parameter $\tau$ tends to infinity. Since the constraint set changes with the solution, we develop an argument using Mosco convergence. We state an algorithm to solve the truncated problem and show its con

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  • We study (2,2) divisors in $P^2 \times P^2$ giving rise to pairs of non-isomorphic, derived equivalent and L-equivalent K3 surfaces of degree 2. In particular, we confirm the existence of such fourfolds as predicted by Kuznetsov and Shinder in \cite{KS}.

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  • The ability to integrate information in the brain is considered to be an essential property for cognition and consciousness. Integrated Information Theory (IIT) hypothesizes that the amount of integrated information ($\Phi$) in the brain is related to the level of consciousness. IIT proposes that to quantify information integration in a system as a whole, integrated information should be measured across the partition of the system at which information loss caused by partitioning is minimized, called the Minimum Information Partition (MIP). The computational cost for exhaustively searching for the MIP grows exponentially with system size, making it difficult to apply IIT to real neural data. It has been previously shown that if a measure of $\Phi$ satisfies a mathematical property, submodularity, the MIP can be found in a polynomial order by an optimization algorithm. However, although the first version of $\Phi$ is submodular, the later versions are not. In this study, we empirically e

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  • We prove existence results for the Lane-Emden type system \[(-\Delta)^{\alpha} u=\left| v \right| ^q (-\Delta)^{\beta} v= \left| u \right|^p \text{ in } B_1 \subset \mathbb{R}^N \frac{\partial^{r} u}{\partial \nu^{r}}=0, \, r=0, \dots, \alpha-1, \text{ on } \partial B_1 \frac{\partial^{r} v}{\partial \nu^{r}}=0, \, r=0, \dots, \beta-1, \text{ on } \partial B_1. \] where $B_1$ is the unitary ball in $\mathbb{R}^N$, $N >\max \{2\alpha, 2\beta \}$, $\nu$ is the outward pointing normal, $\alpha, \beta \in \mathbb{N}$, $\alpha, \beta \ge 1$ and $(-\Delta)^{\alpha}= -\Delta((-\Delta)^{\alpha-1})$ is the polyharmonic operator. A continuation method together with a priori estimates will be exploited. Moreover, we prove uniqueness for the particular case $\alpha=2$, $\beta=1$ and $p, q>1$.

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  • Neighbor's house alarm triggers when I put my car in reverse

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  • Barbed Wire Telephone Lines Brought Isolated Homesteaders Together

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  • Land Registry data reveals London’s secret tunnels

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  • In the Reflection Equation (RE) algebra associated with an involutive or Hecke symmetry $R$ the center is generated by elements ${\rm Tr}_R L^k$ (called the quantum power sums) , where $L$ is the generating matrix of this algebra and ${\rm Tr}_R$ is the $R$-trace corresponding to $R$. We consider the problem: whether it is so in RE-type algebras depending on spectral parameters. Mainly, we deal with algebras similar to those considered in [RS] (we call them the algebras of RS type). These algebras are defined by means of some current $R$-matrices arising from involutive and Hecke symmetries via the so-called Baxterization procedure. We define quantum power sums in the algebras of RS type and show that the lowest quantum power sum in such an algebra is central iff the value of the "charge" entering its definition is critical. Besides, we show that it is also so for higher quantum power sums under a complementary condition on the initial symmetry $R$.

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  • In this paper it is shown that the compact linearization approach, that has been previously proposed only for binary quadratic problems with assignment constraints, can be generalized to arbitrary linear equations with positive coefficients which considerably enlarges its applicability. We discuss special cases of prominent quadratic combinatorial optimization problems where the obtained compact linearization yields a continuous relaxation that is provably as least as strong as the one obtained with an ordinary linearization.

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  • This paper is concerned with "nice" compactifications of manifolds. Siebenmann's iconic dissertation characterized open manifolds M^m (m>5) compactifiable by addition of a manifold boundary. His theorem extends easily to cases where M^m is noncompact with compact boundary; however, when Bd(M^m) is noncompact, the situation is more complicated. The goal becomes a "completion" of M^m, ie, a compact manifold C^m and a compact subset A such that C^m\A = M^m. Siebenmann did some initial work on this topic, and O'Brien extended that work to an important special case. But, until now, a complete characterization had yet to emerge. We provide such a characterization. Our second main theorem involves Z-compactifications. An open question asks whether a well-known set of conditions laid out by Chapman and Siebenmann guarantee Z-compactifiability for a manifold M^m. We cannot answer that question, but we do show that those conditions are satisfied if and only if M x [0,1] is Z-compactifiable. A

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  • A loop is automorphic if all its inner mappings are automorphisms. We construct a large family of automorphic loops as follows. Let $R$ be a commutative ring, $V$ an $R$-module, $E=\mathrm{End}_R(V)$ the ring of $R$-endomorphisms of $V$, and $W$ a subgroup of $(E,+)$ such that $ab=ba$ for every $a$, $b\in W$ and $1+a$ is invertible for every $a\in W$. Then $Q_{R,V}(W)$ defined on $W\times V$ by $(a,u)(b,v) = (a+b,u(1+b)+v(1-a))$ is an automorphic loop. A special case occurs when $R=k<K=V$ is a field extension and $W$ is a $k$-subspace of $K$ such that $k1\cap W = 0$, naturally embedded into $\mathrm{End}_k(K)$ by $a\mapsto M_a$, $bM_a = ba$. In this case we denote the automorphic loop $Q_{R,V}(W)$ by $Q_{k<K}(W)$. We call the parameters tame if $k$ is a prime field, $W$ generates $K$ as a field over $k$, and $K$ is perfect when $\mathrm{char}(k)=2$. We describe the automorphism groups of tame automorphic loops $Q_{k<K}(W)$, and we solve the isomorphism problem for tame automor

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  • This paper is concerned with applications of the theory of approximation and interpolation based on compensated convex transforms developed in [K. Zhang, E. Crooks, A. Orlando, Compensated convexity methods for approximations and interpolations of sampled functions in Euclidean spaces: Theoretical Foundations. SIAM Journal on Mathematical Analysis 48 (2016) 4126-4154]. We apply our methods to $(i)$ surface reconstruction starting from the knowledge of finitely many level sets (or `contour lines'); $(ii)$ scattered data approximation; $(iii)$ image inpainting. For $(i)$ and $(ii)$ our methods give interpolations. For the case of finite sets (scattered data), in particular, our approximations provide a natural triangulation and piecewise affine interpolation. Prototype examples of explicitly calculated approximations and inpainting results are presented for both finite and compact sets. We also show numerical experiments for applications of our methods to high density salt and pepper noi

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  • The Hilbert polynomial of a homogeneous complete intersection is determined by the degrees of the generators of the defining ideal. The degrees of the generators are not, in general, determined by the Hilbert polynomial -- but sometimes they are. When? We give some general criteria and completely answer the question up to codimension 6.

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  • We consider discrete-time dynamics, for cascading failure in DC networks, whose map is composition of failure rule with control actions. Supply-demand at nodes is monotonically nonincreasing under admissible control. Under the failure rule, a link is removed permanently if its flow exceeds its capacities. We consider finite horizon optimal control to steer the network from an arbitrary initial state, defined in terms of active link set and supply-demand at nodes, to a feasible state, i.e., a state that is invariant under the failure rule. There is no running cost and the reward associated with a feasible terminal state is the associated cumulative supply-demand. We propose two approaches for computing optimal control, and provide time complexity analysis for these approaches. The first approach, geared towards tree reducible networks, decomposes the global problem into a system of coupled local problems, which can be solved to optimality in two iterations. In the first iteration, optim

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  • We give a formula relating the order of the Brauer group of a surface fibered over a curve over a finite field to the order of the Tate-Shafarevich group of the Jacobian of the generic fiber. Our result extends the results of Grothendieck, Milne and Gonzalez-Aviles and corrects the formula of Liu, Lorenzini and Raynaud.

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  • In this paper, we consider the area-preserving mean curvature flow with free Neumann boundaries. We show that for a rotationally symmetric $n$-dimensional hypersurface in $\R^{n+1}$ between two parallel hyperplanes will converge to a cylinder with the same area under this flow. We use the geometric properties and the maximal principle to obtain gradient and curvature estimates, leading to long-time existence of the flow and convergence to a constant mean curvature surface.

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  • The Loewner framework for model order reduction is applied to the class of infinite-dimension systems. The transfer function of such systems is irrational (as opposed to linear systems, whose transfer function is rational) and can be expressed as an infinite series of rational functions. The main advantage of the method is the fact that reduced orders models are constructed using only input-output measurements. The procedure can be directly applied to the original transfer function or to the one obtained from the finite element discretization of the PDE. Significantly better results are obtained when using it directly, as it is presented in the experiments section.

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  • In this paper we propose and analyze an energy stable numerical scheme for the Cahn-Hilliard equation, with second order accuracy in time and the fourth order finite difference approximation in space. In particular, the truncation error for the long stencil fourth order finite difference approximation, over a uniform numerical grid with a periodic boundary condition, is analyzed, via the help of discrete Fourier analysis instead of the the standard Taylor expansion. This in turn results in a reduced regularity requirement for the test function. In the temporal approximation, we apply a second order BDF stencil, combined with a second order extrapolation formula applied to the concave diffusion term, as well as a second order artificial Douglas-Dupont regularization term, for the sake of energy stability. As a result, the unique solvability, energy stability are established for the proposed numerical scheme, and an optimal rate convergence analysis is derived in the $\ell^\infty (0,T; \

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  • The sparse group Lasso is a widely used statistical model which encourages the sparsity both on a group and within the group level. In this paper, we develop an efficient augmented Lagrangian method for large-scale non-overlapping sparse group Lasso problems with each subproblem being solved by a superlinearly convergent inexact semismooth Newton method. Theoretically, we prove that, if the penalty parameter is chosen sufficiently large, the augmented Lagrangian method converges globally at an arbitrarily fast linear rate for the primal iterative sequence, the dual infeasibility, and the duality gap of the primal and dual objective functions. Computationally, we derive explicitly the generalized Jacobian of the proximal mapping associated with the sparse group Lasso regularizer and exploit fully the underlying second order sparsity through the semismooth Newton method. The efficiency and robustness of our proposed algorithm are demonstrated by numerical experiments on both the syntheti

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  • Multiclass classification problems such as image annotation can involve a large number of classes. In this context, confusion between classes can occur, and single label classification may be misleading. We provide in the present paper a general device that, given an unlabeled dataset and a score function defined as the minimizer of some empirical and convex risk, outputs a set of class labels, instead of a single one. Interestingly, this procedure does not require that the unlabeled dataset explores the whole classes. Even more, the method is calibrated to control the expected size of the output set while minimizing the classification risk. We show the statistical optimality of the procedure and establish rates of convergence under the Tsybakov margin condition. It turns out that these rates are linear on the number of labels. We apply our methodology to convex aggregation of confidence sets based on the V-fold cross validation principle also known as the superlearning principle. We i

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  • In this paper, we introduce the notion of $k^{th}$-order slant little Hankel operator on the Bergman space with essentially bounded harmonic symbols on the unit disc and obtain its algebraic and spectral properties. We have also discussed the conditions under which $k^{th}$-order slant little Hankel operators commute.

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