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Yunliang Yu, IT Senior Manager

Yunliang Yu

Open source is an investment in the future.

FDS Motto: we serve and empower the faculty.

Contact Info:
Office Location:  029D Physics
Office Phone:  (919) 660-2803
Email Address:   send me a message
Web Page:   http://www.math.duke.edu/~yu

Office Hours:

12:01AM - 12:02AM every other day except today.
Not by appt :-)
Specialties:

Mathematics
Recent Publications

  1. Y. Yu, test 123 (March, 2010). [PNG, PDF]

Famous Sayings:
Your dream will come true, if you eat your soup.
    --- Angela Yu
Don't be a turkey; read a book.
    --- Christina Yu
Security = avoid "unexpected inputs for unintended results".
    --- moi
To learn and practice what is learned from time to time is pleasure, is it not? To have friends from afar is happiness, is it not? To be unperturbed when not appreciated by others is a gentleman, is it not?
    --- Kungfu Zi
Better to light a candle than to curse the darkness.
    --- Chinese Proverb

mathprograms.org, academicjobsonline.org, mathjobs.org, ShortURLs, sharedworkingplace.org, chinesecalligraphyandwoodcarving.

/. headline news :-)

  • Why Elon Musk Doesn't Like Flying Cars
    2017-04-30T14:34:00+00:00
    boley1 quotes Business Insider: According to Elon Musk, the main challenges with flying cars are that they'll be noisy and generate lots of wind because of the downward force required to keep them in the air. Plus, there's an anxiety factor. "Let's just say if something is flying over your head...that is not an anxiety-reducing situation," he said. "You don't think to yourself 'Well, I feel better about today. You're thinking 'Is it going to come off and guillotine me as it comes flying past?'"

    Read more of this story at Slashdot.

  • Intel-Powered Broadband Modems Highly Vulnerable To DoS Attack
    2017-04-30T13:34:00+00:00
    "It's being reported by users from the DSLReports forum that the Puma 6 Intel cable modem variants are highly susceptible to a very low-bandwidth denial-of-service attack," writes Slashdot reader Idisagree. The Register reports: Effectively, if there's someone you don't like, and they are one of thousands upon thousands of people using a Puma 6-powered home gateway, and you know their public IP address, you can kick them off the internet, we're told... According to one engineer...the flaw would be "trivial" to exploit in the wild, and would effectively render a targeted box useless for the duration of the attack... "It can be exploited remotely, and there is no way to mitigate the issue." This is particularly frustrating for Puma 6 modem owners because the boxes are pitched as gigabit broadband gateways: the devices can be potentially choked and knocked out simply by receiving traffic that's a fraction of the bandwidth their owners are paying for... The Puma 6 chipset is used in a number of ISP-branded cable modems, including some Xfinity boxes supplied by Comcast in the US and the latest Virgin Media hubs in the UK. The original submission also notes there's already a class action lawsuit over the performance of cable modems with Intel's Puma 6 chipset, and adds "It would appear the Atom chip was never going to live up to the task it was designed for."

    Read more of this story at Slashdot.

  • Advertisers Are Still Boycotting YouTube Over Offensive Videos
    2017-04-30T10:34:00+00:00
    An anonymous reader quotes the Associated Press:The fallout from the YouTube boycott is likely to be felt through the rest of this year. Skittish advertisers have curtailed their spending until they are convinced Google can prevent their brands from appearing next to extremist clips promoting hate and violence... At one point, about 250 advertisers were boycotting YouTube... The list included big-spending marketers such as PepsiCo, Wal-Mart Stores, Starbucks, AT&T, Verizon, Johnson & Johnson, and Volkswagen. It's unclear how many, if any, of those have returned to YouTube since Google promised to hire more human reviewers and upgrade its technology to keep ads away from repugnant videos. Both Verizon and AT&T, two companies that are trying to expand their own digital ad networks to compete with Google, told The Associated Press that they are still boycotting YouTube. FX Networks confirmed that it isn't advertising on YouTube either. Several other boycotting marketers contacted by AP didn't respond. Thursday CEO Sundar Pichai told analysts that responding to the boycott, Google held "thousands and thousands" of conversations with advertisers, and one analyst now estimates reduced ad spending on YouTube and Google could cost the company $300 million this year alone.

    Read more of this story at Slashdot.

  • Humans Are Already Harassing Security Robots
    2017-04-30T07:34:00+00:00
    An anonymous reader quotes CNN: As robots begin to appear on sidewalks and streets, they're being hazed and bullied. Last week, a drunken man allegedly tipped over a 300-pound security robot in Mountain View, California... Knightscope, which makes the robot that was targeted in Mountain View, said it's had three bullying incidents since launching its first prototype robot three years ago. In 2014, a person attempted to tackle a Knightscope robot. Last year in Los Angeles, people attempted to spray paint a Knightscope robot. The robot sensed the paint and sounded an alarm, alerting local security and the company's engineers... the robot's cameras filmed the pranksters' license plate, making it easy to track them down. The company's security robots are deployed with 17 clients in five states, according to the article, which notes that at best the robots' cameras allow them to "rat out the bullies." But with delivery robots now also hitting the streets in San Francisco and Washington D.C., "the makers of these machines will have to figure out how to protect them from ill-intentioned humans."

    Read more of this story at Slashdot.

  • Debian Developer Imprisoned In Russia Over Alleged Role In Riots
    2017-04-30T04:29:00+00:00
    An anonymous reader writes: "Dmitry Bogatov, Debian developer and Tor node admin, is still being held in a Moscow jail," tweeted the EFF Saturday. IT Wire reports that the 25-year-old math teacher was arrested earlier this month "on suspicion of organizing riots," and is expected to be held in custody until June 8. "The panel investigating the protests claims Bogatov posted several incitory messages on the sysadmin.ru forum; for example, one claim said he was asking people to bring 'bottles, fabric, gasoline, turpentine, foam plastic' to Red Square, according to a post at Hacker News. The messages were sent in the name of one Airat Bashirov and happened to be transmitted through the Tor node that Bogatov was running. The Hacker News post said Bogatov's lawyer had produced surveillance video footage to show that he was elsewhere at the time when the messages were posted. "After Dmitry's arrest," reports the Free Bogatov site, "Airat Bashirov continue to post messages. News outlets 'Open Russia' and 'Mediazona' even got a chance to speak with him." Earlier this month the Debian GNU/Linux project also posted a message of support, noting Dmitry maintains several packages for command line and system tools, and saying their group "honours his good work and strong dedication to Debian and Free Software... we hope he is back as soon as possible to his endeavours... In the meantime, the Debian Project has taken measures to secure its systems by removing Dmitry's keys in the case that they are compromised."

    Read more of this story at Slashdot.

  • Wired Founding Editor Now Challenges 'The Myth of A Superhuman AI'
    2017-04-30T01:24:00+00:00
    Wired's founding executive editor Kevin Kelly wrote a 5,000-word takedown on "the myth of a superhuman AI," challenging dire warnings from Bill Gates, Stephen Hawking, and Elon Musk about the potential extinction of humanity at the hands of a superintelligent constructs. Slashdot reader mirandakatz calls it an "impeccably argued debunking of this pervasive myth." Kelly writes: Buried in this scenario of a takeover of superhuman artificial intelligence are five assumptions which, when examined closely, are not based on any evidence... 1.) Artificial intelligence is already getting smarter than us, at an exponential rate. 2.) We'll make AIs into a general purpose intelligence, like our own. 3.) We can make human intelligence in silicon. 4.) Intelligence can be expanded without limit. 5.) Once we have exploding superintelligence it can solve most of our problems... If the expectation of a superhuman AI takeover is built on five key assumptions that have no basis in evidence, then this idea is more akin to a religious belief -- a myth Kelly proposes "five heresies" which he says have more evidence to support them -- including the prediction that emulating human intelligence "will be constrained by cost" -- and he likens artificial intelligence to the physical powers of machines. "[W]hile all machines as a class can beat the physical achievements of an individual human...there is no one machine that can beat an average human in everything he or she does."

    Read more of this story at Slashdot.

  • Ask Slashdot: Could We Build A Global Wireless Mesh Network?
    2017-04-29T23:19:00+00:00
    An anonymous reader wants to start a grassroots effort to build a self-organizing global radio mesh network where every device can communicate with every other device -- and without any central authority. There is nothing in the rules of mathematics or laws of physics that prevents such a system. But how would you break the problem up so it could be crowdfunded and sourced? How would you build the radios? And what about government spectrum rules... How would you persuade governments to allow for the use of say, 1%, of the spectrum for an unlicensed mesh experiment? In the U.S. it would probably take an Act of Congress to overrule the FCC but a grassroots effort with potential for major technology advances backed by celebrity scientists might be enough to tilt the issue but would there be enough motivation? Is this feasible? Would it amass enough volunteers, advocates, and enthusiastic users? Would it become a glorious example of geeks uniting the world -- or a doomed fantasy with no practical applications. Leave your best thoughts in the comments. Could we build a global wireless mesh network?

    Read more of this story at Slashdot.

  • Developer Shares A Recoverable Container Format That's File System Agnostic
    2017-04-29T22:40:00+00:00
    Long-time Slashdot reader MarcoPon writes: I created a thing: SeqBox. It's an archive/container format (and corresponding suite of tools) with some interesting and unique features. Basically an SBX file is composed of a series of sector-sized blocks with a small header with a recognizable signature, integrity check, info about the file they belong to, and a sequence number. The results of this encoding is the ability to recover an SBX container even if the file system is corrupted, completely lost or just unknown, no matter how much the file is fragmented.

    Read more of this story at Slashdot.

  • NASA Launches Super Balloon To Detect Cosmic Particles From Near Space
    2017-04-29T22:09:00+00:00
    "After seven unsuccessful attempts NASA has launched a stadium-sized balloon in Wanaka," reports the New Zealand Herald, adding that the super-pressure balloon will collect data from "near space" over the next 100 days. Reuters reports: The balloon, designed by NASA to detect ultra-high energy cosmic particles from beyond the galaxy as they penetrate the earth's atmosphere, is expected to circle the planet two or three times. "The origin of these particles is a great mystery that we'd like to solve. Do they come from massive black holes at the centre of galaxies? Tiny, fast-spinning stars? Or somewhere else?" Angela Olinto, a University of Chicago professor and lead investigator on the project, said in a statement.

    Read more of this story at Slashdot.

  • Microsoft's Surface Revenue Drops By $285M (26%)
    2017-04-29T21:04:00+00:00
    An anonymous reader quotes Computerworld: Revenue generated by Microsoft's Surface hardware during the March quarter was down 26% from the same period the year before, the company said yesterday as it briefed Wall Street. For the quarter, Surface produced $831 million, some $285 million less than the March quarter of 2016, for the largest year-over-year dollar decline ever... The revenue decline "indicates that the aging product needs a refresh badly," Jack Gold, principal analyst at J. Gold Associates, wrote in a note to clients today. "Price cutting and competing vendors' products will continue to create declines until new product is released, rumored for later this year." Microsoft threw cold water on any significant changes to the Surface line before June, forecasting that the current quarter will also post a revenue decline.

    Read more of this story at Slashdot.

  • Russian-Controlled Telecom Hijacks Traffic For Mastercard, Visa, And 22 Other Services
    2017-04-29T19:59:00+00:00
    An anonymous reader quotes the security editor at Ars Technica: On Wednesday, large chunks of network traffic belonging to MasterCard, Visa, and more than two dozen other financial services companies were briefly routed through a Russian government-controlled telecom under unexplained circumstances that renew lingering questions about the trust and reliability of some of the most sensitive Internet communications. Anomalies in the border gateway protocol -- which routes large-scale amounts of traffic among Internet backbones, ISPs, and other large networks -- are common and usually the result of human error. While it's possible Wednesday's five- to seven-minute hijack of 36 large network blocks may also have been inadvertent, the high concentration of technology and financial services companies affected made the incident "curious" to engineers at network monitoring service BGPmon. What's more, the way some of the affected networks were redirected indicated their underlying prefixes had been manually inserted into BGP tables, most likely by someone at Rostelecom, the Russian government-controlled telecom that improperly announced ownership of the blocks.

    Read more of this story at Slashdot.

  • Some Of The Pentagon's Critical Infrastructure Still Runs Windows 95 And 98
    2017-04-29T18:55:00+00:00
    SmartAboutThings writes: The Pentagon is set to complete its Windows 10 transition by the end of this year, but nearly 75% of its control system devices still run Windows XP or other older versions, including Windows 95 and 98. A Pentagon official now wants the bug bounty program of the top U.S. defense agency expanded to scan for vulnerabilities in its critical infrastructure. DefenseOne raises the possibility of "building and electrical systems, HVAC equipment and other critical infrastructure laden with internet-connected sensors," with one military program manager saying "A lot of these systems are still Windows 95 or 98, and that's OK -- if they're not connected to the internet." Windows Report notes that though Microsoft no longer supports Windows XP, "the Defense Department is paying Microsoft to continue providing support for the legacy OS."

    Read more of this story at Slashdot.

  • Startups Struggle For Survival As Investors Turn 'Picky'
    2017-04-29T17:49:00+00:00
    An anonymous reader quotes The Wall Street Journal: Eighteen months ago, Beepi Inc. was rapidly expanding its online used-car business to 16 U.S. cities where people could buy cut-rate vehicles adorned with giant shiny bows. Beepi doesn't exist anymore. After burning through more than $120 million in capital, the startup failed to raise more cash and shut down in February. Its roughly 270 employees cleared out of the cavernous Mountain View, California headquarters, leaving behind the ping-pong table and putting green. Beepi's rapid demise offers a glimpse into the changing fortunes of Silicon Valley startups, many of which have struggled to adjust since a two-year investment frenzy came to an end. In 2014 and 2015, mutual funds, hedge funds and other investors pumped billions into companies that they now see as overvalued, and unlikely to pull off an initial public offering. As venture capitalists became more discerning, investment in U.S. tech startups plummeted by 30% in dollar terms last year from a year earlier. The article also points out that "much of the money still being invested is pouring into the upper echelon of highly valued start-ups like Airbnb and WeWork or younger ones with clear paths to profit," leaving "scores" of previously well-funded startups now struggling to survive.

    Read more of this story at Slashdot.

  • Encrypted WhatsApp Message Recovered From Westminster Terrorist's Phone
    2017-04-29T16:44:00+00:00
    Bruce66423 brings word that a terrorist's WhatsApp message has been decrypted "using techniques that 'cannot be disclosed for security reasons', though 'sources said they now have the technical expertise to repeat the process in future.'" The Economic Times reports: U.K. security services have managed to decode the last message sent out by Khalid Masood before he rammed his high-speed car into pedestrians on Westminster Bridge and stabbed to death a police officer at the gates of Parliament on March 22. The access to Masood's message was achieved by what has been described by security sources as a use of "human and technical intelligence"... The issue of WhatsApp's encrypted service, which is closed to anyone besides the sender and recipient, had come under criticism soon after the attack. "It's completely unacceptable. There should be no place for terrorists to hide. We need to make sure that organisations like WhatsApp, and there are plenty of others like that, don't provide a secret place for terrorists to communicate with each other," U.K. home secretary Amber Rudd had said. Security sources say the message showed the victim's motive was military action in Muslim countries, while the article adds that though ISIS claimed responsibility for the attack, "no evidence has emerged to back this up."

    Read more of this story at Slashdot.

  • Wikipedia Is Being Blocked In Turkey
    2017-04-29T15:46:00+00:00
    Nine hours ago, Ilgaz wrote: The Turkey Blocks monitoring network has verified restrictions affecting the Wikipedia online encyclopedia in Turkey. A block affecting all language editions of the website [was] detected at 8:00AM local time Saturday 29 April. The loss of availability is consistent with internet filters used to censor content in the country. stikves added Access to Wikipedia has been blocked in Turkey as a result of "a provisional administrative order" imposed by the Turkish Telecommunications Authority (BTK)... Turkey Blocks said an administrative blocking order is usually expected to precede a full court blocking order in coming days. While the reason for the order was unknown early on Saturday, a statement on the BTK's website said: "After technical analysis and legal consideration based on the Law Nr. 5651, ADMINISTRATION MEASURE has been taken for this website (wikipedia.org) according to Decision Nr. 490.05.01.2017.-182198 dated 29/04/2017 implemented by Information and Communication Technologies Authority." The BBC adds reports from Turkish media that authorities "had asked Wikipedia to remove content by writers 'supporting terror.'"

    Read more of this story at Slashdot.

 

dept@math.duke.edu
ph: 919.660.2800
fax: 919.660.2821

Mathematics Department
Duke University, Box 90320
Durham, NC 27708-0320