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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 :-)

  • Russian Online Trolls Resist The Light
    2016-05-31T07:00:00+00:00
    Rick Zeman writes: Since the beginning of the public Internet on Usenet and now following on comment boards worldwide, live the trolls, the online creatures dedicated to stirring up trouble with their versions of online flaming, fact-twisting, and overall being a menace to online society. Russia, by paying state-sponsored trolls, has elevated the troll to the level of professional propagandists spewing the party line. In neighboring Finland, a country again precariously balanced between Europe and the Russian bear, Finnish journalist Jessikka Aro's investigations have opened a new front in the (dis)information war (Warning: source may be paywalled) where "'There are so many layers of fakery you get lost,' said Ms. Aro, who was awarded the Finnish Grand Prize for Journalism in March," reports the NYT. All because "A member of the European Union with an 830-mile-long border with Russia, Finland has stayed outside the United States-led military alliance but, unnerved by Russian military actions in Ukraine and its saber-rattling in the Baltic Sea, has expanded cooperation with NATO and debated whether to apply for full membership." The NYT article explores many of the actions that the Russian propagandists use to keep Finland out of NATO, and some of the more indefensible ones directed personally at Aro. She says, "They get inside your head, and you start thinking: If I do this, what will the trolls do next?"

    Read more of this story at Slashdot.

  • Microsoft Removes 260-Character Path Length Limit In Windows 10 Redstone
    2016-05-31T03:30:00+00:00
    An anonymous reader quotes a report from Softpedia: Windows 10 build 14352, a preview version of the upcoming Anniversary Update (also known as Redstone), comes with an eagerly awaited change that Microsoft hasn't yet announced publicly. The 260-character path length limit in Windows can be removed with the help of a new policy, thus allowing you to run operations with files regardless of their path or file name. While this new rule is not enabled by default, admins can turn it on by following these instructions. Launch the Registry Editor by clicking the Start menu and typing "regedit.exe," and then navigate to the following path: HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy Objects\{48981759-12F2-42A6-A048-028B3973495F}Machine\System\CurrentControlSet\Policies. Look for an entry called "LongPathsEnabled," and if it does not exist, simply right-click Policies, select New DWORD (32-bit), name it "LongPathsEnabled" (without the quotes), enter value 1, and you're good to go. The description of the preview reads, "Enabling NTFS long paths will allow manifested win32 applications and Windows Store applications to access paths beyond the normal 260 char limit per node. Enabling this setting will cause the long paths to be accessible within the process." While the Windows 10 preview build 1452 has been made available last week, according to Windows Central, a Microsoft team member says that the company could released Windows 10 Mobile build 14352 for Insiders on Tuesday, May 31.

    Read more of this story at Slashdot.

  • ASUS Unveils $599 Home Robot 'Zenbo'
    2016-05-31T01:40:00+00:00
    An anonymous reader writes: In addition to the razor thin ZenBook 3, Asus unveiled a cute talking robot for the home at this week's Computex trade show in Taipei. The robot, called Zenbo, is priced at $599 and is pitched as a personal assistant that can help look after elderly relatives or read stories to the kids. It's about two feet tall and rolls around on wheels, with a display that can show animated faces or be used for making video calls and streaming movies. When asked, "Hey Zenbo, is it true you can take pictures?" by ASUS Chairman Jonney Shih, the robot replied with, "Yes, I can take photographs." Zenbo took a photo of him on stage with the audience in the background when Shih told it to. The robot doesn't have an official release date yet, but developers can sign up for a software kit to build applications for it now.

    Read more of this story at Slashdot.

  • Microsoft Warns of ZCryptor Ransomware With Self-Propagation Features
    2016-05-31T00:55:00+00:00
    An anonymous reader writes from a report issued by Softpedia on May 27: Microsoft and several other security researchers have detected the first ransomware versions that appears to have self-propagation features, being able to spread to other machines on its own by copying itself to shared network drives or portable storage devices automatically. Called ZCryptor, this ransomware seems to enjoy quite the attention from crooks, who are actively distributing today via Flash malvertising and boobytrapped Office files that infect the victim if he enables macro support when opening the file. This just seems to be the latest addition to the ransomware family, one which recently received the ability to launch DDoS attacks while locking the user's computer.

    Read more of this story at Slashdot.

  • Computer Generates Largest Math Proof Ever At 200TB of Data
    2016-05-31T00:10:00+00:00
    An anonymous reader quotes a report from Phys.Org: A trio of researchers has solved a single math problem by using a supercomputer to grind through over a trillion color combination possibilities, and in the process has generated the largest math proof ever -- the text of it is 200 terabytes in size. The math problem has been named the boolean Pythagorean Triples problem and was first proposed back in the 1980's by mathematician Ronald Graham. In looking at the Pythagorean formula: a^2 + b^2 = c^2, he asked, was it possible to label each a non-negative integer, either blue or red, such that no set of integers a, b and c were all the same color. To solve this problem the researchers applied the Cube-and-Conquer paradigm, which is a hybrid of the SAT method for hard problems. It uses both look-ahead techniques and CDCL solvers. They also did some of the math on their own ahead of giving it over to the computer, by using several techniques to pare down the number of choices the supercomputer would have to check, down to just one trillion (from 10^2,300). Still the 800 processor supercomputer ran for two days to crunch its way through to a solution. After all its work, and spitting out the huge data file, the computer proof showed that yes, it was possible to color the integers in multiple allowable ways -- but only up to 7,824 -- after that point, the answer became no. Is the proof really a proof if it does not answer why there is a cut-off point at 7,825, or even why the first stretch is possible? Does it really exist?

    Read more of this story at Slashdot.

  • 'Huge Wake Up Call': Third of Central, Northern Great Barrier Reef Corals Dead
    2016-05-30T23:25:00+00:00
    iONiUM quotes a report from The Sydney Morning Herald: More than one-third of the coral reefs of the central and northern regions of the Great Barrier Reef have died in the huge bleaching event earlier this year, Queensland researchers said. Corals to the north of Cairns -- covering about two-thirds of the Great Barrier Reef -- were found to have an average mortality rate of 35 percent, rising to more than half in areas around Cooktown. Bleaching occurs when abnormal conditions, such as warm seas, cause corals to expel tiny photosynthetic algae, called zooxanthellae. Corals turn white without these algae and may die if the zooxanthellae do not recolonize them. "It is fair to say we were all caught by surprise," Professor Hughes, director of the ARC Centre of Excellence for Coral Reef Studies at James Cook University, said. "It's a huge wake up call because we all thought that coral bleaching was something that happened in the Pacific or the Caribbean which are closer to the epicenter of El Nino events." The report says, "The northern end of the Great Barrier Reef was home to many 50- to 100-year-old corals that had died and may struggle to rebuild before future El Ninos push tolerance beyond thresholds."

    Read more of this story at Slashdot.

  • Stephen Hawking Calls Trump A 'Demagogue' Who Appeals 'To The Lowest Common Denominator'
    2016-05-30T22:40:00+00:00
    An anonymous reader writes: British astrophysicist Stephen Hawking told ITV's morning show that Donald Trump, the presumptive Republican Party candidate for U.S. president, "is a demagogue who seems to appeal to the lowest common denominator." He said, "Gone are the days we could stand on our own against the world. We need to be part of a larger group of nations, both for our security and our trade." ABC News writes, "Stephen Hawking understands the workings of the universe -- but says he cannot fathom the popularity of Donald Trump. He went on to say that British voters should keep the United Kingdom in the European Union in a June 23 referendum, saying the EU provides essential support for British scientific research as well as its economy and security.

    Read more of this story at Slashdot.

  • Iran Forces Messaging Apps To Move Data To Iranian Servers
    2016-05-30T21:55:00+00:00
    An anonymous reader writes: According a report from Reuters, the Iranian government wants to be able to track private and semi-private conversations on messaging apps, and has given companies behind popular messaging apps one year to move their data onto servers in Iran. As it stands, many social networks are already blocked in Iran, and now the government wants to control even more online communication platforms. Apps like WhatsApp and Telegram, which have become incredibly popular in Iran, allow users to communicate with no government control. With Telegram, users can contact hundreds of people by creating groups. Now, even though WhatsApp for example is required to move their data to Iranian servers, it's unlikely the government will be able to intercept messages from the app since it features end-to-end encryption. WhatsApp can't even read the content of communications -- only WhatsApp users can decrypt the messages in their conversations. Apple's iMessage also features an encrypted messaging protocol, and Telegram does too, but users need to start "secret conversations" with end-to-end encryption.

    Read more of this story at Slashdot.

  • Eric Holder Says Snowden Performed 'Public Service'
    2016-05-30T21:10:00+00:00
    An anonymous reader writes from a report via CNN: Former U.S. Attorney General Eric Holder says Edward Snowden performed a "public service" by triggering a debate over surveillance techniques, but still must pay a penalty for illegally leaking a trove of classified intelligence documents. "We can certainly argue about the way in which Snowden did what he did, but I think that he actually performed a public service by raising the debate that we engaged in and by the changes that we made," Holder told David Axelrod on "The Axe Files," a podcast produced by CNN and the University of Chicago Institute of Politics. "Now I would say that doing what he did -- and the way he did it -- was inappropriate and illegal," Holder added. "I think that he's got to make a decision. He's broken the law in my view. He needs to get lawyers, come on back, and decide, see what he wants to do: Go to trial, try to cut a deal. I think there has to be a consequence for what he has done." "But," Holder emphasized, "I think in deciding what an appropriate sentence should be, I think a judge could take into account the usefulness of having had that national debate." You can listen to the podcast with Eric Holder here.

    Read more of this story at Slashdot.

  • Bitcoin Price Jumps 21% Over 4 Days, Reaching a 21-Month High
    2016-05-30T20:25:00+00:00
    An anonymous reader shares a TechCrunch report: Bitcoin is back! Or at least, there are positive signs indicating that bitcoin might not be as dead as everybody thought. Bitcoins are now trading at $547.40 on Bitfinex (the largest USD/bitcoin exchange according to Bitcoinity). And it represents a big 21.4 percent price jump over just four days. Today's price represents a 21-month high. Surprisingly, bitcoin prices had been relatively stable for the last two months before this weekend's jump. What's the reason behind this jump? It's hard to say. Huobi and OKCoin, the two dominant Chinese exchanges, have seen many new sign-ups, as well as many buy orders. Increasingly, bitcoin's price variations are correlated with macroeconomic trends in China. These trends tell us that China still fears a deflation.

    Read more of this story at Slashdot.

  • Telus To Shutter CDMA Service On January 31, 2017
    2016-05-30T19:45:00+00:00
    An anonymous reader writes: With most Canadian mobile devices on some form of HSPA+ or LTE network, you don't hear mention of CDMA that often anymore. And for good reason; carriers like Telus, which still maintain their CDMA network for legacy customers, plan to mothball the tech over the next few years. We now have a definitive date when Telus customers will no longer be able to use their old CDMA device. Over the weekend, the company sent text messages stating, "CDMA service ends January 31, 2017. Move to our 4G network with great offers."

    Read more of this story at Slashdot.

  • Estonian President Expresses Desire For More Digitally-Integrated Europe
    2016-05-30T19:05:00+00:00
    In a wide-ranging interview with Ars Technica, Estonian President Toomas Hendrik talked about European Digital Single Market (DSM), an ambitious goal that seeks to make commerce flow as smoothly across the 28-member block as it does in the United States. He cites the example of iTunes. From the report: What Estonia and Finland are doing is a step towards the DSM -- but there remain all kinds of national-level laws that stop Europe from being truly unified. "Take iTunes," President Ilves continued. "iTunes are based on credit cards. Credit cards are national. I cannot buy an iTunes record for my wife who has a Latvian credit card. I cannot buy her an iTunes record because I have an Estonian iTunes. This is true of virtually everything that is connected to digital services. And certainly this is why Estonia is at the forefront of the European Digital Single Market. As I like to say, it's easier to ship a bottle of Portuguese wine from southern Portugal in the Algarve and sell it in northern Lapland, than it is for me to buy an iTunes record across the Estonian-Latvian border."The report is worth a read in its entirety.

    Read more of this story at Slashdot.

  • Canada's Energy Superpower Status Threatened As World Shifts Off Fossil Fuel
    2016-05-30T18:20:00+00:00
    Robson Fletcher, reporting for CBC News: Canada's status as an "energy superpower" is under threat because the global dominance of fossil fuels could wane faster than previously believed, according to a draft report from a federal government think-tank obtained by CBC News. "It is increasingly plausible to foresee a future in which cheap renewable electricity becomes the world's primary power source and fossil fuels are relegated to a minority status," reads the conclusion of the 32-page document, produced by Policy Horizons Canada. "It's absolutely not pie in the sky," said Michal Moore from the University of Calgary's School of Public Policy. "These folks are being realistic -- they may not be popular, but they're being realistic." Marty Reed, CEO of Evok Innovations -- a Vancouver-based cleantech fund created through a $100-million partnership with Cenovus and Suncor -- had a similar take after reading the draft report.

    Read more of this story at Slashdot.

  • Net Neutrality Is Complicated: Wikipedia Founder Jimmy Wales
    2016-05-30T17:35:00+00:00
    In an interview, Wikipedia founder Jimmy Wales backed the principle of Net neutrality, but added that enabling poor people to access the Internet is equally important. Wales also defended Wikipedia Zero, a project that aims to provide select services free of cost on mobile devices in developing markets. He said :Wikipedia Zero follows a very strict set of principles such as no money is ever exchanged and so on. Net neutrality is such a complicated topic, it is something that I am extremely passionate about and I think is incredibly important. And at the same time I think getting access to knowledge for poorest people of world is also very important. Sometimes those two things can be in tension and we have to be really careful about it. I think fundamental thing is that we maintain and open and free Internet.

    Read more of this story at Slashdot.

  • Tesla To Hold Gigafactory Grand Opening on July 29
    2016-05-30T16:50:00+00:00
    Tesla's mammoth 13-acre battery making Gigafactory isn't due to begin production on lithium ion cells until next year, but according to a report on Fortune, the factory's grand opening is to be held on July 29. According to a report on Bloomberg, as of earlier this month, only 14 percent of the Gigafactory has been built so far. Though, Tesla is already utilizing it to produce Powerpacks and Powerwalls. The factory will apparently cost at least $5 billion to make. (Thanks to an anonymous reader for sharing the link.)

    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