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  • For a finite group $G$, let $d(G)$ denote the minimal number of elements required to generate $G$. In this paper, given a finite almost simple group $G$ and any maximal subgroup $H$ of $G$, we determine a precise upper bound for $d(H)$. In particular, we show that $d(H)\leq 5$, and that $d(H)\geq 4$ if and only if $H$ occurs in a known list. This improves a result of Burness, Liebeck and Shalev. The method involves the theory of crowns in finite groups.

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  • We present a data-driven framework called generative adversarial privacy (GAP). Inspired by recent advancements in generative adversarial networks (GANs), GAP allows the data holder to learn the privatization mechanism directly from the data. Under GAP, finding the optimal privacy mechanism is formulated as a constrained minimax game between a privatizer and an adversary. We show that for appropriately chosen adversarial loss functions, GAP provides privacy guarantees against strong information-theoretic adversaries. We also evaluate the performance of GAP on multi-dimensional Gaussian mixture models and the GENKI face database.

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  • The Bouncy Particle Sampler (BPS) is a Monte Carlo Markov Chain algorithm to sample from a target density known up to a multiplicative constant. This method is based on a kinetic piecewise deterministic Markov process for which the target measure is invariant. This paper deals with theoretical properties of BPS. First, we establish geometric ergodicity of the associated semi-group under weaker conditions than in [10] both on the target distribution and the velocity probability distribution. This result is based on a new coupling of the process which gives a quantitative minorization condition and yields more insights on the convergence. In addition, we study on a toy model the dependency of the convergence rates on the dimension of the state space. Finally, we apply our results to the analysis of simulated annealing algorithms based on BPS.

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  • In this article, we will analyze the global existence of solutions for the fractional diffusion reaction equation by applying Splitting-type methods, to functions that have two main characteristics, these are direct sum of functions of periodic type and functions that tend to zero at infinity. Global existence results are obtained for each particular characteristic, for then finally combining both results.

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  • An anonymous reader shares a report: A hacker gained access to a developer's npm account earlier this week and injected malicious code into a popular JavaScript library, code that was designed to steal the npm credentials of users who utilize the poisoned package inside their projects. The JavaScript (npm) package that got compromised is called eslint-scope, a sub-module of the more famous ESLint, a JavaScript code analysis toolkit. The hack took place on the night between July 11 and 12, according to the results of a preliminary investigation posted on GitHub a few hours ago. "One of our maintainers did observe that a new npm token was generated overnight (said maintainer was asleep)," said Kevin Partington, ESLint project member. Partington believes the hacker used the newly-generated npm token to authenticate and push a new version of the eslint-scope library on the npm repository of JavaScript packages.

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  • Designing and building a distributed data store in Go [pdf]

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  • Carriers argue that 5G will enable intelligent vehicles and the Internet of Things, but not everyone is convinced

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  • Facebook says it will not remove fake news from its platform because it does not violate its community standards. According to the BBC, Facebook said publishers often had "very different points of view" and removing fabricated posts would be "contrary to the basic principles of free speech." Instead, it is choosing to demote posts in the news feed that it deems to be fake news. From the report: Facebook has been scrutinized for its role in spreading fake news after evidence emerged that Russia tried to influence U.S. voters using the social network. On Wednesday, the company held an event in New York where it sought to convince journalists it was tackling the problem. The company said it would not remove fake news that did not break its rules but would down-rank content that had been marked as false. "We allow people to post it as a form of expression, but we're not going to show it at the top of News Feed," a spokeswoman told CNN.

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    Facebook Makes Moves on Instagram Users

    07-14 Hacker News 20

    Facebook Makes Moves on Instagram Users

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  • George Hotz is on a hacker crusade against the ‘scam’ of self-driving cars

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  • The PC market has seen its first growth quarter in six years, according to research firm Gartner. The streak is over: Gartner found PC shipments were up globally in Q2 2018, the first quarter of year-over-year global PC shipment growth since the first quarter of 2012. Gartner estimates that worldwide PC shipments grew 1.4 percent to 62.1 million units in Q2 2018. The top five vendors were Lenovo, HP, Dell, Apple, and Acer. Lenovo in particular saw big gains (its highest growth rate since the first quarter of 2015), although that's largely due in part to the inclusion of units from its joint venture with Fujitsu. The economic crisis is over, and people and companies are buying PCs again.

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  • An anonymous reader shares a report: This is the first time FIFA, soccer's governing body, has allowed video replay to be used to make penalty calls in a World Cup. And while fans of basketball and American football are used to the referees stopping the game to consult video footage, soccer purists say it's ruining everything. The major complaint is that it's making the matches much longer than the typical 90-minute games. Martin Rogers, a sports columnist for USA Today, says Video Assistant Referee (or VAR) is "slow, clunky and unpredictable." Over the phone from Russia, where he's reporting on the World Cup, he jokes, "I remember back in the day, when if a game kicked off at 3 o'clock in the afternoon, you'd be all wrapped up by 4:45." Rogers says this type of technology works well for American football and basketball. "When you look at the calls that are used for replay, in basketball for example, it's normally factual. It's based on, 'Did a player get a shot off before the clock ex

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  • How the BBC and ITV are fixing delays on World Cup live streams

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    Instagram is Down [Updated]

    07-14 Slashdot 22

    According to thousands of users, Instagram website and app are facing technical issues. Users attempting to visit the website are seeing a "5xx Server Error", while on the app, they are getting "Couldn't refresh feed." According to DownDetector, a service which monitors outages on the web, more than 2,000 people have reported issues with Facebook-owned Instagram in the last 10 minutes. Update: As of 19:20 GMT, Instagram appears to have resolved the issue.

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  • Reported bidding war means Buffy, Firefly creator got the deal before filming a pilot.

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  • Addressing a growing concern by privacy advocates and users alike over the usage of facial recognition by government bodies, Microsoft urged the US government on Friday to start thinking about what limits should be set on the use of such technologies. From a report: In a blog post, Microsoft also said it is consulting with outside groups to help set its own policies for how it will use and sell such technology. Face recognition can be used for a range of purposes, from reuniting missing kids to mass surveillance. Currently, there are few rules for those using or selling the technology. "The only effective way to manage the use of technology by a government is for the government proactively to manage this use itself," Microsoft president Brad Smith said in a blog post. "And if there are concerns about how a technology will be deployed more broadly across society, the only way to regulate this broad use is for the government to do so." For its own part, Smith said Microsoft is going to m

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  • Community creates new cosmetics, features, and levels that run on real hardware.

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  • As the first phase of 5G NR wraps up and the 3GPP finishes defining the communications protocol, the standards body also has identified specific frequency bands intended for 5G.

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  • According to a new study by Hub Entertainment Research, viewers are increasingly defaulting to on-demand sources like Netflix, Amazon Prime Video, and Hulu instead of live TV. The study found that only 39% of viewers tune into live programming from a traditional pay-TV provider, down from 47% last year. On-demand sources, collectively, were the first choice for 48% of viewers. Deadline reports: For viewers aged 18-34, the pattern is more stark -- only about a quarter (26%) of the demo lists live TV as a default, compared with 35% a year ago. One clear influence on consumer behavior is the increase in TV sources -- the average person has 4.5 distinct sources to choose from (including linear TV, DVR, VOD, Netflix, etc.). That number is up from 3.7 in 2014. Among viewers 18-34, the number is higher, at 5.1 sources -- plus, Hub found that fully 50% of 18-34-year-olds subscribe to at least two of the "big three" SVOD services, Netflix, Amazon or Hulu. Even older generations accustomed to th

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  • To encourage unbounded, collective intelligence, offices may need physical boundaries.

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  • From a report: Gartner found PC shipments were up globally in Q2 2018, the first quarter of year-over-year global PC shipment growth since the first quarter of 2012. Gartner estimates that worldwide PC shipments grew 1.4 percent to 62.1 million units in Q2 2018. The top five vendors were Lenovo, HP, Dell, Apple, and Acer. Lenovo in particular saw big gains (its highest growth rate since the first quarter of 2015), although that's largely due in part to the inclusion of units from its joint venture with Fujitsu.

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  • Windows 10 migrations are prompting corporate customers to buy new PCs.

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  • Jelani Cobb on the F.B.I. agent Peter Strzok’s testimony Thursday to a joint hearing of the House Judiciary Committee and House Oversight and Government Reform Committee.

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  • According to a new paper from Oxford Internet Institute researchers Victoria Nash and Andrew Przybylski, internet filters rarely work to keep adolescents away from online porn. Basically, the filters are expensive and they don't work. "Internet filtering tools are expensive to develop and maintain, and can easily 'underblock' due to the constant development of new ways of sharing content. Additionally, there are concerns about human rights violations -- filtering can lead to 'overblocking', where young people are not able to access legitimate health and relationship information." TechCrunch reports: The researchers "found that Internet filtering tools are ineffective and in most cases [and] were an insignificant factor in whether young people had seen explicit sexual content." The study's most interesting finding was that between 17 and 77 households "would need to use Internet filtering tools in order to prevent a single young person from accessing sexual content" and even then a filt

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  • Orthogonal polynomials on quadratic curves in the plane are studied. These include orthogonal polynomials on ellipses, parabolas, hyperbolas, and two lines. For an integral with respect to an appropriate weight function defined on any quadratic curve, an explicit basis of orthogonal polynomials is constructed in terms of two families of orthogonal polynomials in one variable. Convergence of the Fourier orthogonal expansions is also studied in each case. As an application, we see that the resulting bases can be used to interpolate functions on the real line with singularities of the form $|x|$, $\sqrt{x^2+ \epsilon^2}$, or $1/x$, with exponential convergence.

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  • Earlier this month, The New York Times reported that a number of smart TV makers include services from companies that track a range of viewer information about their customers. Now, two Democratic US senators are asking the Federal Trade Commission to investigate privacy problems related to Internet-connected televisions. From a report: "Many Internet-connected smart TVs are equipped with sophisticated technologies that can track the content users are watching and then use that information to tailor and deliver targeted advertisements to consumers," Sens. Ed Markey (D-Mass.) and Richard Blumenthal (D-Conn.) wrote in a letter yesterday to FTC Chairman Joseph Simons. "Regrettably, smart TV users may not be aware of the extent to which their televisions are collecting sensitive information about their viewing habits." The letter asked the FTC to "launch an investigation into the privacy policies and practices of smart TV manufacturers." When contacted by Ars, an FTC spokesperson confirmed

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  • Democrats want FTC probe of privacy policies and practices of smart TV makers.

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  • Snow – Conceal messages in ASCII text (2013)

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  • Special counsel Robert Mueller has obtained a new indictment charging 12 Russian intelligence officers with hacking Democrats to interfere with the 2016 presidential election, and with stealing information of about 500,000 American voters, the Justice Department announced Friday. From a report: The indictment lodged in Washington, D.C., accuses the Russian spies of hacking into the Democratic National Committee and the presidential campaign of Hillary Clinton, and of releasing emails obtained from that cybersnooping with a a goal of influencing the election. The accused also hacked into state boards of elections, secretaries of state, and into companies that provided software used to administer elections, according to Deputy Attorney Rod Rosenstein. Rosenstein said he briefed President Donald Trump about the case earlier in the week.

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  • Stencila: An open source office suite for reproducible research

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  • Tesla spokesperson says the company still plans to introduce a $35,000 model.

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  • Susan Glasser writes about Donald Trump’s agenda for his summit with Vladimir Putin next week, and how the indictment announced today by the special counsel, Robert Muller, may affect the meeting.

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  •  

    The Andromeda journey continues

    07-14 OSnews 19

    Multiple sources have told me that Microsoft plans to overhaul the software and hardware before releasing the device. At this time, the software and hardware do not create a compelling solution that would move the needle for Microsoft and more importantly the Surface brand which is why when it came to the ‘go, no go' decision earlier this year, it was not given the green light. [...] What you need to know about Andromeda is that the project is still alive inside of Microsoft but that it will not be released anytime soon. The company will re-work the hardware and software, see if it will move the needle, and if not, re-work again, until they find the right formula. Microsoft will not ship a project simply because the first phase is done, they are trying to get this right so that they don't have another Lumia/Surface RT project on their hands. There's just not enough UWP applications at this point in time to support such a device.

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    The Egison Programming Language

    07-14 Hacker News 23

    The Egison Programming Language

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    The Great Apple Keyboard Cover-Up

    07-14 Hacker News 22

    The Great Apple Keyboard Cover-Up

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    The science of zero-knowledge proofs

    07-14 Hacker News 22

    The science of zero-knowledge proofs

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    US Lifts ZTE Export Ban

    07-14 Slashdot 21

    The U.S. Commerce Department has lifted the export ban on Chinese telecommunications giant ZTE now that it has met all the terms required to get a full reprieve. "Officials confirmed that ZTE had put $400 million in escrow on top of other requirements, including the payment of a $1 billion fine, replacing key leadership and accepting outside monitors that will ensure it honors U.S. export controls," reports Engadget. From the report: Strictly speaking, this more of a probation -- as with the last time, the Commerce Department is suspending its ban rather than removing it entirely. The monitors will keep watch over ZTE during the entire 10-year period of the suspension, so it won't have much choice but to fly straight if it wants to avoid another ban. The earlier ban would have "only" lasted seven years. The Senate recently passed a bill that would reinstate U.S. sanctions on the company, but the White House has vowed to squash it before it becomes law.

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  • Your weekly selection of awesome robot videos

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    WebAssembly is more than the web

    07-14 Hacker News 22

    WebAssembly is more than the web

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  • Richard Brody recommends movies to stream on Amazon Prime, including “Grigris,” “In the Spirit,” and “That Uncertain Feeling.”

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  • If you suddenly became unable to work because of an illness or accident, disability insurance can help protect your lifestyle.

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  • Eric Lach discusses Robert Mueller’s latest indictment on the Russians who hacked e-mails from the Democratic Party and Hillary Clinton in advance of the 2016 Presidential election.

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  • Eric Lach discusses Robert Mueller’s latest indictment on the Russians who hacked e-mails from the Democratic Party and Hillary Clinton in advance of the 2016 Presidential election.

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  • Louisa Thomas on Kevin Anderson’s arduous semifinal victory over John Isner at Wimbledon.

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  • XARs: An efficient system for self-contained executables

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  • All underutilized systems are essentially the same, but each overutilized system tends to be overloaded in its own way. If one's goal is to maximize the use of the available computing resources, overutilization tends not to be too far away, but when it happens, it can be hard to tell where the problem is. Sometimes, even the fact that there is a problem at all is not immediately apparent. The pressure-stall information patch set from Johannes Weiner may make life easier for system administrators by exposing more information about the real utilization state of the system.

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  • After nearly four decades of development, interactive home robots have made exactly as much progress as you'd expect

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  • Sprint on Thursday unveiled a new, more complicated lineup of unlimited mobile data plans. Sprint goes from having one plan starting at $60 per month to four different options costing $50 to $70 a month. "The main price hike hits customers who want to watch streaming video at HD quality instead of being reduced to DVD quality," reports Fortune. From the report: A new "unlimited plus" plan most resembles the carrier's current one, with subscribers allowed to use up to 15 GB monthly before experiencing slowed download speeds, receiving HD-quality streaming video, and getting free Hulu and Tidal subscriptions. It costs $70 for one line, rising to $180 for four lines. But Sprint also added a "limited time" promotion that cuts the price to $50 to $100 per month for customers who buy a new phone or bring their own device. A cheaper "unlimited basic" plan, starting at $60 for one line and up to $140 for four lines, slows downloads to 3G speeds after just 500 MB, downgrades streaming to DVD-qu

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  • For the first time, we have an optical signal to match a cosmic neutrino.

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  • Synaptics and AMD today announced that they're teaming up on a biometric security solution for consumer and business PCs built on AMD platforms. But for Microsoft watchers, the most curious portion of the announcement is that the biometric tech is squarely focused on a mysterious "next-generation operating system" from Microsoft. [...] It's not entirely clear what the biometric security OS is that Synaptics is referring to, as Microsoft itself hasn't announced any forthcoming releases. However, it could be related to a Microsoft project called Polaris, a more modern version of Windows 10 for desktops that Windows Central senior editor Zac Bowden reported on earlier this year. Built on an internal project called Windows Core OS, which aims to turn Windows into a modular OS, Polaris is said to focus on desktop, laptop, and 2-in-1 form factors. The goal of Polaris is to provide a shell that Windows users are familiar with, but while leaving behind legacy components in favor of

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  • Dhall – A Distributed, Safe Configuration Language

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  • VR technology hasn’t been a hit with consumers, so companies are taking it everywhere from specially built arenas to airports.

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  • Gore is recruiting startups to Silicon Valley to make wearables or flexible electronics from the same material used in Gore-Tex

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  • Have we overestimated the effectiveness of psychotherapy?

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  • Installed hacked versions of Telegram, WhatsApp, and tracked users' location and SMS.

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  • Vizaline says its service is not surveying, but Mississippi authorities disagree.

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  • Implementing Open Source Container Security, Part 1: Runtime Security

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  • Interview with Paul Romer On Hong Kong, Charter Cities and Growth Theory (2015)

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    Learn how to design large-scale systems

    07-13 Hacker News 22

    Learn how to design large-scale systems

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    Legal Systems Very Different from Ours

    07-13 Hacker News 19

    Legal Systems Very Different from Ours

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  • Living with a best-selling Indian phone for 10 days

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  • Microsoft Urges Congress to Regulate Use of Facial Recognition

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  • HMD does nearly everything right with this $269 wonder phone.

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  • The guy who designed the Raptor engine has even bigger plans for what's next.

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    Security updates for Friday

    07-13 LWN 19

    Security updates have been issued by Debian (cinnamon), Fedora (docker, firefox, jetty, and knot-resolver), Oracle (gnupg2), Scientific Linux (gnupg2), SUSE (gdk-pixbuf, java-1_8_0-openjdk, libopenmpt, php7, and rsyslog), and Ubuntu (dns-root-data, dnsmasq, and thunderbird).

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  • Show HN: Announce and discover GitHub repos

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  • Things We Need to Know About Technological Change (1998) [pdf]

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  • What Is a Blazar? It’s Like Staring Down the Barrel of a Black Hole

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  • Archaeologists analyzed the mummified man's last meal down to the DNA level.

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  • Ötzi’s last supper: mummified hunter's final meal revealed

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  • We study a covert queueing channel (CQC) between two users sharing a round robin scheduler. Such a covert channel can arise when users share a resource such as a computer processor or a router arbitrated by a round robin policy. We present an information-theoretic framework to model and derive the maximum reliable data transmission rate, i.e., the capacity of this channel, for both noiseless and noisy setups. Our results show that seemingly isolated users can communicate with a high rate over the covert channel and demonstrate the possibility of significant information leakage and privacy threats brought by CQCs in round robin schedulers. Moreover, we propose practical finite-length code constructions, which achieve the capacity limit.

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  • Millimeter Wave (mmWave) band provides a large spectrum to meet the high-demand capacity by the 5th generation (5G) wireless networks. However, to fully exploit the available spectrum, obstacles such as high path loss, channel sparsity, and hardware complexity should be overcome. To this end, the present paper aims to design a new multiple-input multiple-output (MIMO) system using lens-based multi-beam reconfigurable antennas. The proposed MIMO system uses complete lens at the transmitter and incomplete lens at the receiver. To reduce hardware complexity, we utilize an optimal beam selection technique. Our analysis demonstrates that the proposed MIMO system along with the optimal beam selection technique increases the average signal-to-noise ratio (SNR). Also, simulations show that the system achieves full-diversity gain.

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  • Existing dimensionality reduction methods are adept at revealing hidden underlying manifolds arising from high-dimensional data and thereby producing a low-dimensional representation. However, the smoothness of the manifolds produced by classic techniques over sparse and noisy data is not guaranteed. In fact, the embedding generated using such data may distort the geometry of the manifold and thereby produce an unfaithful embedding. Herein, we propose a framework for nonlinear dimensionality reduction that generates a manifold in terms of smooth geodesics that is designed to treat problems in which manifold measurements are either sparse or corrupted by noise. Our method generates a network structure for given high-dimensional data using a nearest neighbors search and then produces piecewise linear shortest paths that are defined as geodesics. Then, we fit points in each geodesic by a smoothing spline to emphasize the smoothness. The robustness of this approach for sparse and noisy dat

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  • We extend the Sauer-Shelah-Perles lemma to an abstract setting that is formalized using the language of lattices. Our extension applies to all finite lattices with nonvanishing M\"obius function, a rich class of lattices which includes all geometric lattices (or matroids) as a special case. For example, our extension implies the following result in Algebraic Combinatorics: let $\mathcal{F}$ be a family of subspaces of $\mathbb{F}^n_q$. We say that $\mathcal{F}$ shatters a subspace $U$ if for every subspace $U' \leq U$ there is $F \in \mathcal{F}$ such that $F \cap U = U'$. Then, if $|\mathcal{F}| > \genfrac{[}{]}{0pt}{}{n}{0}_q + \cdots + \genfrac{[}{]}{0pt}{}{n}{d}_q$ then $\mathcal{F}$ shatters some $(d+1)$-dimensional subspace (where $\genfrac{[}{]}{0pt}{}{n}{k}_q$ denotes the number of $k$-dimensional subspaces in $\mathbb{F}^n_q$).

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  • In this paper we address the design of decentralized feedback control laws inducing consensus and prescribed spatial patterns over a singular Cucker-Smale type model. The control design consists of a feedback term regulating the distance between each agent and pre-assigned neighbours. Such a design represents a multidimensional extension of existing control laws for 1d platoon formation control. For the proposed controller, we study consensus formation, collision-avoidance and formation control features in terms of energy estimates for the closed-loop system. Numerical experiments in 1, 2 and 3 dimensions assess the different features of the proposed design.

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  • While Shannon entropy is related to the growth rate of multinomial coefficients, we show that Tsallis 2-entropy is connected to their $q$-version; when $q$ is a prime power, these coefficients count the number of flags in $\mathbb{F}_q^n$ with prescribed length and dimensions ($\mathbb{F}_q$ denotes the field of order $q$). In particular, the $q$-binomial coefficients count vector subspaces of given dimension. We obtain this way a combinatorial explanation for non-additivity. We show that statistical systems whose configurations are described by flags provide a frequentist justification for the maximum entropy principle with Tsallis statistics. We introduce then a discrete-time stochastic process associated to the $q$-binomial distribution, that generates at time $n$ a vector subspace of $\mathbb{F}_q^n$. The concentration of measure on certain "typical subspaces" allows us to extend the asymptotic equipartition property to this setting. We discuss the applications to information theor

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  • We show that the twisted K-theory of the classifying space of a p-local finite group is isomorphic to the completion of the Grothendieck group of twisted representations of the fusion system with respect to the augmentation ideal of the representation ring of the fusion system. We use this result to compute the K-theory of the Ruiz-Viruel exotic 7-local finite groups.

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  • Stochastic model predictive control (SMPC) has been a promising solution to complex control problems under uncertain disturbances. However, traditional SMPC approaches either require exact knowledge of probabilistic distributions, or rely on massive scenarios that are generated to represent uncertainties. In this paper, a novel SMPC approach is proposed by actively learning a data-driven uncertainty set from available data with machine learning techniques. A systematical procedure is then proposed to further calibrate the uncertainty set, which gives appropriate probabilistic guarantee. The resulting data-driven uncertainty set is more compact than traditional norm-based sets, and can help reducing conservatism of control actions. Meanwhile, the proposed method requires less data samples than traditional scenario-based SMPC approaches, thereby enhancing the practicability of SMPC. Finally the optimal control problem is cast as a single-stage robust optimization problem, which can be so

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  • We introduce a new iterative method to recover a real compact supported potential of the Schr\"odinger operator from their fixed angle scattering data. The method combines a fixed point argument with a suitable approximation of the resolvent of the Schr\"odinger operator by partial sums associated to its Born series. Convergence is established for potentials with small norm in certain Sobolev spaces. As an application we show some numerical experiments that illustrate this convergence.

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  • The invariance identity involving three operations $D_{f,g}:X\times X\rightarrow X$ of the form \begin{equation*} D_{f,g}\left( x,y\right) =\left( f\circ g\right) ^{-1}\left( f\left( x\right) \oplus g\left( y\right) \right) \text{,} \end{equation*} is proposed. The connections of these operations with means is investigated. The question when the invariance equality admits three means leads to a composite functional equation. Problem to determine its continuous solutions is posed.

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